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  • A number of new studies on ovarian cancer show “promising” results for patients who develop chemo-resistance
  • A Dutch study uses conventional chemotherapeutics more intensively
  • Another study uses a new class of drug discovered by the UK’s Institute of Cancer Research
  • Genetic testing is playing an increasing role in the reduction of chemo-resistance
  • Since 2014 the Royal Marsden NHS Trust Hospital in London has employed genetic profiling of ovarian cancer patients
  • The UK’s Chief Medical Officer suggests that whole genome sequencing should become standard practice on the NHS across cancer care
  • A new class of chemotherapeutic agent is directed at targeting cancers with defective DNA-damage repair
  • Improvements in cancer care have been both scientific and organizational
  • Utilizing and sequencing the treatment options for ovarian cancer may have a significant impact on the overall survival rates of patients
  • Multidisciplinary teams are transforming ovarian cancer care 
 
Improving ovarian cancer treatment 

Part II

Part-1 described ovarian cancer, the difficulties of diagnosing the disease early, and the challenges of developing effective screening mechanisms for it in pre-symptomatic women. Here, in part-2, we report new studies, which hold out the prospect of improved treatment options for women living with ovarian cancer. Both Commentaries draw on some of the world’s most eminent ovarian cancer clinicians and scientists.
 
1

Established chemotherapy agents combined and used intensively

The first study we describe is Dutch, published in 2017 in the British Journal of Cancer. It reports findings of a pioneering type of intensive chemotherapy, which was effective in 80% of patients with advanced ovarian cancer and whose first line of chemotherapy had failed. Currently, such patients have few options because more than 50% do not respond to follow-up chemotherapy.
 
Intensive combinations
The study, led by Dr. Ronald de Wit, of the Rotterdam Cancer Institute, involved 98 patients who first responded to chemotherapy only later to relapse. Patients in the study were divided into three groups according to the severity of their condition, and treated with a combination of two well established chemotherapy agents:  cisplatin and etopside, but the new treatment used the drugs much more intensively than usual.
 
Usually, chemotherapy is delivered as a course of a number of 21-day sessions (cycles) over several months. Between cycles patients are given time to recover from the toxic side effects, including neurotoxicity, nephrotoxicity, ototoxicity, and chemotherapy-induced nausea and vomiting (CINV). In de Wit’s study the combined chemotherapy drugs were given intensively, on a weekly basis, along with drugs to prevent adverse side effects.
 
Findings
Among the group of women in de Wit’s study who were most seriously ill, 46% responded to the new treatment, compared with less than 15% for current therapies. The response rates of the two groups of women who were least ill to the new treatment were 92% and 91%. This compares to responses of 50% and 20 to 30% with standard therapies. Overall, 80% of the women's tumours shrank, and 43% showed a complete response, with all signs of their cancers disappearing.
 
Immediate benefit
"We were delighted by the success of the study. The new drug combination was highly effective at keeping women alive for longer, giving real hope to those who would otherwise have had very little . . . . We were worried the women would be too ill to cope with the treatment, but in fact, they suffered relatively few side effects. And since these drugs are readily available, there's no reason why women shouldn't start to benefit from them right away," says de Wit.
 
2
 
ONX-0801 study

The second study we report was presented at the 2017 American Society of Clinical Oncology (ASCO) meeting in Chicago. It describes findings of an experimental new treatment that was found to dramatically shrink advanced ovarian cancer tumors, which researchers suggest is, “much more than anything that has been achieved in the last 10 years”.
 
“Very promising” findings
Dr. Udai Banerji, the leader of the study, is the Deputy Director of Drug Development at the UK’s Institute of Cancer Research (ICR). Banerji and his team were testing a drug, known as ONX-0801, for safety, but found that tumors, in half of the 15 women studied, shrank during the trial. A response Banerji called, “highly unusual”, and “very promising”. The drug, which is, “a completely new mechanism of action,” could add, “upward of six months to the lives of patients with minimal side effects”. If further clinical studies prove the drug’s effectiveness, it could potentially be used in early-stage ovarian cancer where, “the impact on survival may be better,” says Banerji.
 
New class of drug
ONX-0801 is the first in a new class of drug discovered by the ICR, and tested with the Royal Marsden NHS Foundation Trust. It attacks ovarian cancer by mimicking folic acid in order to enter the cancer cells. The drug then kills these cells by blocking a molecule called thymidylate synthase. ONX-0801 could be effective in treating the large group of chemo-resistant sufferers for whom there are currently limited options. Additionally, because the new therapy targets cancer cells and does not affect surrounding healthy cells, there are fewer side effects. Further, experts have developed tests to detect the cells that respond positively to this new treatment, which means oncologists can identify those women who are likely to benefit from the therapy the most.
 
Cautious note
Although the study is said to be “very promising”, Michel Coleman, Professor of Epidemiology at the London School of Hygiene & Tropical Medicine, suggests caution in interpreting its findings as it is such a small study and while, “shrinkage of tumors is important . . . it is not the same as producing the hoped-for extension of survival for women with ovarian cancer.”
 
3
 
Genetic testing

Resistance to chemotherapy can be reduced by DNA testing to obtain an increased knowledge of the molecular mechanisms of ovarian cancer pathogenesis, which facilitate personalized therapies that target certain subtypes of the disease. “Some people choose to have DNA testing because either they have developed cancer or family members have,” says David Bowtell, Professor and Head of the Cancer Genomics and Genetics Program at Peter MacCallum Cancer Centre, Melbourne, Australia. “In the context of cancer, personalized medicine is the concept that we look into the cancer cell and understand for that person what specific genetic changes have occurred in their cancer. Based on those specific changes, for that person we then decide on a type of therapy, which is most appropriate for the genetic changes that have occurred in that cancer . . . . . Typically this involves taking a sample of the cancer, running it through DNA sequencing machines, and using bioinformatics to interpret the information. Then, the results, which include gene mutations need to be interpreted by a multidisciplinary team, in order to decide the best possible treatment options for that particular patient,” says Bowtell: see videos below.
.
 
How do genetic mutations translate into personalised medicine?


How is personalised medicine implemented?
 
Mainstreaming cancer genetics
Since 2014 the Royal Marsden NHS Trust Hospital in London has employed genetic profiling of ovarian cancer patients, and have used laboratories with enhanced genetic testing capabilities to streamline and speed up processing time, lower costs, and help meet the large and growing demand for rapid, accurate and affordable genetic testing. The program called, Mainstreaming Cancer Genetics, helps women cancer patients make critical decisions about their treatment options. Currently, fewer than 33% of patients are tested, but this study spearheaded the beginning of a significant change. In her 2017 Annual Report, Professor Dame Sally Davies, England’s Chief Medical Office suggested that within the next 5 years all cancer patients should be routinely offered DNA tests on the NHS to help them select the best personalized treatments.
 

Bringing genetic testing to patients
According to Nazneen Rahman, Professor and Head of the Division of Genetics and Epidemiology at the ICR, and Head of the Cancer Genetics Unit at the Royal Marsden Hospital, London, “There were two main problems with the traditional system for gene testing. Firstly, gene testing was slow and expensive, and secondly the process for accessing gene testing was slow and complex . . . . We used new DNA sequencing technology to make a fast, accurate, affordable cancer gene test, which is now used across the UK. We then simplified test eligibility and brought testing to patients in the cancer clinic, rather than making them have another appointment, often in another hospital.” 
 

More people benefiting from affordable rapid advanced genetic testing
Treatment strategies that improve the selectivity of current chemotherapy have the potential to make a dramatic impact on ovarian cancer patient outcomes. The Marsden is now offering genetic tests to three times more cancer patients a year than before the program started. The new pathway is faster, with results arriving within 4 weeks, as opposed to the previous 20-week waiting period. According to Rahman, “Many other centres across the country and internationally are adopting our mainstream gene testing approach. This will help many women with cancer and will prevent cancers in their relatives.” If the UK government acts on the recommendations of Davies, there could be a national center for genetic testing within the next 5 years.
 
4

PARP Inhibitors and personalized therapy
 
Since 2 seminal 2005 publications in Nature,  (Bryant et al, 2005; and Farmer et al, 2005) which reported the extremely high sensitivity of BRCA mutant cell lines to the enzyme poly (ADP-ribose) polymerase (PARP) inhibition, there has been a scientific race to exploit a new class of cancer drug called PARP inhibitors. The family of PARP inhibitors represents a widely researched and promising alternative for the targeted therapy of ovarian malignancies. Over the past few years, PARP inhibitors have successfully moved into clinical practice, and are now used to help improve progression-free survival in women with recurrent platinum-sensitive ovarian cancer.

 
Recent (PARP) approvals
In 2014, olaparib was the first PARP inhibitor to obtain EU approval as a treatment for ovarian cancer patients who had become resistant to platinum-based chemotherapy. In 2017, the FDA granted the drug ‘priority review’ as a maintenance therapy in relapsed patients with platinum-sensitive ovarian cancer while confirmatory studies are completed. In December 2016, the FDA granted ‘accelerated approval’ for rucaparib, another (PARP) inhibitor for the treatment of women with advanced ovarian cancers who have been treated with two or more chemotherapies, and whose tumors have specific BRCA gene mutations. 
 
Early in 2017, the drug niraparib was the first PARP inhibitor to be approved by the FDA for the maintenance treatment of adult patients with recurrent gynaecological cancers who are resistant to platinum-based chemotherapy.  The approval was based upon data from an international randomized, prospectively designed phase III clinical study, which enrolled 553 patients, and showed a clinically meaningful increase in progression-free survival (PFS) in women with recurrent ovarian cancer, regardless of BRCA mutation or biomarker status. In conjunction with the accelerated 2017 FDA approval for rucaparib, the FDA also approved a BRCA diagnostic test, which identifies patients with advanced ovarian cancer eligible for treatment with rucaparib.
 

New class of chemotherapies
PARP inhibitors may represent a potentially significant new class of chemotherapeutic agents directed at targeting cancers with defective DNA-damage repair. Currently, these drugs have a palliative indication for a relatively small cohort of patients. In order to widen the prospective patient population that would benefit from PARP inhibitors, predictive biomarkers based on a clearer understanding of the mechanism of action, and a better understanding of their toxicity profile will be required. Once this is achieved PARP inhibitors could to be employed in the curative, rather than the palliative setting.
 
5
 
The future of cancer care and multidisciplinary teams
 
According to Hani Gabra, Professor of Medical Oncology at Imperial College, London; and Head of AstraZeneca’s Oncology Discovery Unit, we now have “many options” for treating ovarian cancer. However, “how we utilize and sequence these options may have a significant impact on the overall survival of a patient. Better understanding of the disease through science is constantly turning up new options. For the first time in the last 5 years we are developing options in real time for patients. Patients almost are able to benefit from these options as they are relapsing from their disease. Keeping patients alive for longer allows them to access new treatments . . . It’s truly remarkable to see this in real time as a doctor,” says Gabra: see video.
 

A significant number of mostly private patients diagnosed with ovarian cancer draw comfort from the belief that they, “have the best oncologist”.  This view fails to grasp the challenges facing individual clinicians acting on their own to treat a devilishly complex disease such as ovarian cancer. “The main improvements in cancer care have been organizational and scientific.” says Gabra. “It is not enough to create new science and new treatments. It is also important to rigorously implement these. The most effective way to do this is via a ‘tumor board’ or a ‘multidisciplinary clinic or team’, where various specialists such as surgeons, radiotherapists, medical oncologists, pathologists, clinical nurse specialists, etc come together and discuss each individual patient. Such multidisciplinary discussion results in the best utilizations of currently available treatment options in the right sequence. It’s difficult to do this for a doctor acting on his or her own and making isolated decisions . . . Multidisciplinary decision-making has transformed cancer care,” says Gabra: see video.
 
 
Takeaways

This Commentary provides a flavor of some of the recent advances in ovarian cancer research and care, and suggests that treatment options have improved in the 4 years since Maurice Saatchi described ovarian cancer care as, “degrading, medieval and ineffective” leading “only to death”. However, it is worth stressing that care is both organizational and scientific, and multidisciplinary teams can transform care and prolong life.
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  • Ovarian cancer is a deadly disease that is challenging to diagnose and manage
  • Although it only accounts for 3% of cancers in women, it is the 5th leading cause of cancer death among women
  • If diagnosed and treated early before it spreads the 5-year survival rate is 92%
  • But only 15% of women with ovarian cancer are diagnosed early
  • The disease is hard to diagnose because it is rare, the symptoms are relatively benign, and there is no effective screening
  • Ovarian cancer is not one disease, but a collection of subtypes each demanding specific treatment pathways
  • Gold standard treatment is surgery followed by chemotherapy
  • A large proportion of patients develop resistance to chemotherapy
 
Improving ovarian cancer treatment

Part I
 
Are things beginning to improve for people living with ovarian cancer? When the British advertising magnate Lord Maurice Saatchi’s wife died of ovarian cancer in 2012 he described her treatment as, “degrading, medieval and ineffective” leading “only to death”. Ovarian cancer patients have long had limited treatment options, which have not changed much in the past two decades, but recently things have begun to change.

 
In this Commentary
 
This is the first of a 2-part Commentary on ovarian cancer, which briefly describes the condition, explains the difficulties of diagnosing it early, and discusses some of the challenges of developing effective screening mechanisms for the cancer in pre-symptomatic women. Part 2, which will follow separately next week, reports new studies, which hold out the prospect of improved treatment options for women living with ovarian cancer. It also suggests that improvements in ovarian cancer care are both organizational and scientific. Experts believe that they now have a number of treatment options available to them. Utilising and sequencing these appropriately can have a significant impact on the overall survival rates of patients. Multidisciplinary teams, which are not universally available to all ovarian cancer patients, bring together all specialisms involved in the therapeutic pathway to consider and suggest optimal treatment steps for individual patients, and make a significant contribution to improved ovarian cancer care. Both Commentaries draw on some of the world’s most eminent ovarian cancer clinicians and scientists.
 
Ovarian cancer: a complex and deadly disease
 
The ovaries are a pair of small organs located low in the stomach that are connected to the womb and store a woman’s supply of eggs. Ovarian cancer is driven by multicellular pathways, and is better understood as a collection of subtypes with changing origins and clinical behaviors, rather than as a single disease. The tumors often have heterogeneous cell populations, which form unique microcellular environments. The prevalence of ovarian cancer among gynecological malignancies is rising, and is one the most deadly and hard to treat malignancies. While the disease only accounts for about 3% of cancers in women, it is one of the most common types of cancer in women, the 5th leading cause of cancer-related death among women, and the deadliest of gynecologic cancers. The risk of ovarian cancer increases with age. It is rare in women younger than 40, most ovarian cancers develop after menopause. 50% of all ovarian cancers are found in women 63 or older. According to the American Cancer Society the five-year survival rate for all ovarian cancers is 45%. Most women are diagnosed with late-stage ovarian disease and, the 5-year survival rates for these patients are roughly 30%. Age adjusted survival rates of ovarian cancer are improving in most developed countries. For instance, between 1970 and 2010, the 10-year survival rates for ovarian cancer in England increased by 16%, and the 5-year survival rates have almost doubled. This is because of the favorable trends in the use of oral contraceptives, which were introduced early in developed countries. Declines in menopausal hormone use may also have had a favorable effect in older women as well as improved diagnosis, management and therapies. According to Public Health England, over the past 20 years the incidence of ovarian cancer in England has remained fairly stable, although it has decreased slightly in the last few years. Between 2008 and 2010 in England, 36% of some 14,000 women diagnosed with ovarian cancer died in the first year, and more than 1,600 died in the first month. There were 7,378 new cases of ovarian cancer in the UK in 2014 and more than 4,000 women died from the disease.
 
Benign symptoms difficult to diagnose

If ovarian cancer is diagnosed and treated early before it spreads from the ovaries to the abdomen, the 5-year relative survival rate is 92%. However, only 15% of all ovarian cancers are found at this early stage.  This is because it is hard to diagnose since the disease is so rare, the symptoms are relatively benign, and there is no effective screening. As a result, the illness tends not to be detected until the latter stages in around 60% of women, when the prognosis is poor. In about 20% of cases the disease is not diagnosed until it is incurable. Feeling bloated most days for three weeks or more is a significant sign of ovarian cancer. Other symptoms include: feeling full quickly, loss of appetite, pelvic or stomach pain, needing to urinate more frequently than normal, changes in bowel habit, feeling very tired, and unexplained weight loss.
 
“Tumors go from the earliest stage 1 directly to stage 3”
In the video below Hani Gabra, Professor of Medical Oncology at Imperial College, London; and Head of AstraZeneca’s Oncology Discovery Unit says, “Ovarian cancer is often diagnosed late because in many cases the disease disseminates into the peritoneal cavity almost simultaneously with the primary declaring itself. Unlike other cancers, the notion that ovarian cancer progresses from stage 1 to stage 2, to stage 3 is possibly mythological. The reality is, these cancer cells often commence in the fallopian tube with a very small primary tumor, which disseminates directly into the peritoneal cavity. In other words, the tumors go from the earliest of stage 1 directly to stage 3."
 
 
Ovarian cancer screening and CA-125

For years scientists have been searching for an effective screening test for ovarian cancer in pre-symptomtic women. The 2 most common are transvaginal ultrasound (TVUS) and the CA-125 blood test. The former uses sound waves to examine the uterus, fallopian tubes, and ovaries by putting an ultrasound wand into the vagina. It can help find a tumor in the ovary, but cannot tell if the tumor is cancerous or benign. Most tumors identified by TVUS are not cancerous. So far, the most promising screening method is CA-125, which measures a protein antigen produced by the tumor.
 
CA-125 studies
To-date, 2 large ovarian cancer screening studies have been completed: one in the US, and another in the UK. Both looked at using the CA-125 blood test along with TVUS to detect ovarian cancer. In these studies, more cancers were found in the women who were screened, and some were at an early stage. But the outcomes of the women who were screened were no better than the women who were not screened: the screened women did not live longer and were not less likely to die from ovarian cancer.

Another study published in 2017 in the Journal of Clinical Oncology screened 4,346 women over 3 years at 42 centers across the UK, undertook follow-up studies 5 years later, and came to similar conclusions as the 2 previous studies. Further, “there are a number of non-ovarian diseases, which can cause elevated CA-125’s. Breast cancer, endometriosis, and irritation of the peritoneal cavity can all cause elevated CA-125,” says Michael Birrer, Director of Medical Gynecologic Oncology at the Massachusetts General Hospital and Professor of Medicine at Harvard University.


Controversial findings
Findings from screening tests using CA-125 can give false positives for ovarian cancer, and this puts pressure on patients to have further, often unnecessary interventions, which sometimes include surgery. Also, the limitations of the CA-125 test mean that many women with early stage ovarian cancer will receive a false negative from testing, and not get further treatment for their condition. Thus, the potential role of CA-125 for the early detection of ovarian cancer is controversial, and therefore it has not been adopted for widespread screening in asymptomatic women.
 
In the video below Birrer explains that, “pre-operatively and during therapy physicians will usually check CA-125 as a measure of the effectiveness of the therapy. At the completion of therapy one would anticipate that the CA-125 would be normal. After that, it is somewhat controversial as to whether follow-up with CA-125 to test for recurring disease is clinically relevant,” says Birrer. Since the discovery of CA-125 in 1981, there has been intense research focus on novel biomarkers for cancer, and significant scientific advances in genomics, proteomic, and epigenomics etc., which have been extensively used in scientific discovery, but as yet no new major cancer biomarkers have been introduced to practicing oncologists. 

 
Limited treatment options

As most ovarian cancer patients are diagnosed late when the disease has already spread, treatment options are limited. The first line treatment is surgery called debulking, (also known as cytoreduction or cytoreductive surgery), which is the reduction of as much of the volume (bulk) of a tumor as possible. 
 
Be prepared for extensive surgery
Whether a patient is a candidate for surgery depends on a number of factors including the type, size, location, grade and stage of the tumor, pre-existing medical conditions, and in the case of a recurrence, when the last cancer treatment was performed, as well as general health factors such as age, physical fitness and other medical comorbidities. People diagnosed with ovarian cancer, “need to be prepared to have extensive surgery because the real extent of the tumor dissemination cannot be detected by conventional imagining pre-operatively,” says Professor Christina Fotopoulou, consultant gynaecological oncologist at Queen Charlotte's & Chelsea Hospital, London: see video below. 
 
 
Platinum resistance

Surgery is usually followed by chemotherapy. There are more than 100 chemotherapy agents used to treat cancer either alone or in combination. Chemotherapy drugs target cells at different phases of the process of forming new cells, called the cell cycle. Understanding how these drugs work helps oncologists predict, which drugs are likely to work well together. Clinicians can also plan how often doses of each drug should be given based on the timing of the cell phases. Chemotherapy drugs can be grouped by their chemical composition, their relationship with other drugs, their utility in treating specific forms of cancer, and their side effects.  
 
You can reduce chemotherapy resistance by using a combination of drugs that target different processes in the cancer so that the probability that the cancer will simultaneously become resistant to both drugs is much lower than if you use one drug at a time, ” says David Bowtell,  Professor and Head of the Cancer Genomics and Genetics Program at Peter MacCallum Cancer Centre, Melbourne, Australia: see video:
 
 
Improving the chemotherapy agent cisplatin
The standard chemotherapy treatment for ovarian cancer is a combination of a platinum compound, such as cisplatin or carboplatin, and a taxane, which represents a class of drug originally identified from plants. Since cisplatin’s discovery in 1965 and its FDA approval in 1978, it has been used continuously in treatments for several types of cancer, and is best known as a cure for testicular cancer. Scientists have searched for ways to improve the anti-tumor efficacy of platinum based drugs, reducing their toxicity, strengthening them against resistance by expanding the class to include several new analogues of cisplatin, and putting these through clinical studies to broaden the different types of cancers against which they can be safely used.
 
Slow progress transitioning research into clinical practice
Despite these endeavors, platinum resistance remains a significant clinical challenge. Between 55 and 75% of women with ovarian cancer develop resistance to platinum based chemotherapy treatments. Significant research efforts have been dedicated to understanding this, but there has been relatively slow progress transitioning the research into effective clinical applications. According to Birrer, “the mechanism of platinum resistance from a molecular standpoint has not been well defined. It is likely to be heterogeneous, which means that each patient’s tumor may be slightly different. The hope is for targeted therapies and personalised medicine to have a chance of overcoming this, in that we could characterize the mechanism of the platinum resistance and apply and target therapy.”
 
2 theories of platinum resistance
In the video below, Birrer posits 2 theories to explain platinum resistance. “One suggests that under the influence of platinum the tumor changes and becomes resistant. Another suggests that there are 2 groups of cells to begin with. The vast majority of the tumor is sensitive, but there are small clusters of resistant cells. Once you kill the sensitive cells you have only the resistant cells left. Although these 2 theories have been around for about 25 years, there are no definitive data to suggest which theory is right. I have a personal scientific bias to think that the resistant cells are present at the time that we start the therapy. Being able to identify and characterize these cells upfront would be a radical breakthrough because then we would be able to target them at a time when they are only a small portion of the tumor,” says Birrer.
 
 
Takeaways

Saatchi is right; for decades ovarian cancer treatment has been wanting, but studies we describe in part-2 of this Commentary suggest that the tide might be turning for people living with ovarian cancer. So don't miss part-2 next week!
 
 
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  • Each year cancer kills 8m people worldwide and cost billions
  • 40% of cancer deaths could be prevented by early detection
  • Nearly half of all cancer sufferers are diagnosed late when the tumors have already spread
  • Victims and doctors often miss early warning signs of cancer
  • Traditional tissue biopsies used to diagnose cancer are invasive, slow, costly, and often yield insufficient tissue
  • New blood tests are being devised that simultaneously detect cancer early and inform where the cancer is in the body
  • Such tests - liquid biopsies - are positioned to end the late diagnosis of cancer
  • But before liquid biopsies become common practice they need to overcome a number of significant challenges
  
World’s first blood tests that detect and locate cancer
 
Just as there is a global race among immunotherapists to enhance cancer treatment, so there is a parallel race among bioengineers to speed up and improve the detection of cancer. Such races are important because nearly half of all cancer sufferers are diagnosed late, when their tumors have already metastasized: 30% to 40% of cancer deaths could be prevented by early detection and treatment.
 
Here we describe advances in blood tests - “liquid biopsies” - which can simultaneously detect cancer early, and identify its tissue of origin. We also, describe the growing commercialization of the technology, and some significant hurdles it still has to be overcome.
 
A costly killer disease

Each year cancer kills more than 8m people worldwide, 0.6m in the US and nearly 0.17m in the UK. Survival rates for pancreatic, liver, lung, ovarian, stomach, uterine and oesophageal cancers are particularly low. A large proportion of people do not know they have cancer, and many primary care doctors fail to detect its early warning signs. According to The Journal of Clinical Oncology, a staggering 44% of some types of cancers are misdiagnosed. A significant proportion of people discover that they have cancer only after presenting a different condition at A&E. Each year, the total cost of cancer to the UK’s exchequer is nearly £20bn. In the US, national spending on cancer is expected to reach US$156bn by 2020. And as populations age so some cancer prevalence rates increase, despite substantial endeavours to reduce the burden of the disease.
  
The UK: a stereotypical case

The UK is indicative of what is happening elsewhere in the developed world with regard to cancer diagnosis and treatment. Epidemiological trends suggest that although progress is being made to fight the disease, much work is still required. Death rates for a number of individual cancer types have declined, but rates for a few cancers have increased.

Recently, the UK’s Department of Health invested £450m to improve diagnosis, including giving primary care doctors better access to tests such as CT and MRI scans. But each year there are still some 0.17m cancer deaths in the UK, and 1 in 4 British cancer patients are unlikely to live longer than 6 months after diagnosis because they and their doctors have missed early signs of the disease. For example, in the UK only 23% of lung cancer cases are diagnosed early, as are 32% of cases of non-Hodgkin lymphoma, and 44% of ovarian cancer.

Not only does late detection increase morbidity and mortality, it significantly increases treatment costs. According to the UK’s NHS National Intelligence Network, a case of ovarian cancer detected early costs an average of £5,000 to treat, whereas one detected late at stage three or four costs £15,000. Similarly, a colon cancer patient detected early typically costs £3,000, while one not identified until a later stage would cost some £13,000.

 
Traditional tissue biopsies

Currently, oncologists look to pathologists for assistance in tumor diagnosis. Indeed, oncologists cannot proceed with therapy without a tissue diagnosis, nor are they able to discuss prognosis with the patient. After detecting a tumor through a physical examination or imaging, doctors use traditional tissue biopsies to gather information on the attributes of a patient’s cancer.
 
These pinpoint a cancer’s mutations and malignancy, but solid tissue biopsies are not always straightforward. While some cancers are easily accessed, others are hidden deep inside the body or buried in critical organs. Beyond the physical challenge, sampling from such tumors can be dangerous to patients, and once achieved, they do not always inform on current tumor dynamics. Further, traditional solid tissue biopsies are costly and time consuming to perform; they can yield insufficient tissue to obtain a good understanding of the tumor, and they can be hampered by a patient’s comorbidities, and lack of compliance.

 
Two significant studies
 
Although solid tumor tissue is still the gold standard source for clinical molecular analyses, cancer-derived material circulating in the bloodstream has become an appealing alternative showing potential to overcome some of the challenges of solid tissue biopsies.

Findings of two significant studies of liquid biopsies published in 2017 promise a more effective and patient-friendly method for diagnosing cancer: one in the journal Genome Biology, and the other in the journal Nature Genetics. Both studies are on the cusp of developing the world’s first simple blood test, which can both detect early stage cancer, and identify where in the body the cancer is located.

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The Genome Biology study
 
​The study, reported in Genome Biology, describes findings of a blood test, referred to as the CancerLocator, which has been developed by Jasmine Zhou, Professor of Biological and Computer Sciences and her team at the University of California, Los Angeles (UCLA). The  Locator detected early stage cancer in 80% of breast, lung and liver cases.
 
Zhou and her colleagues devised a computer program that uses genetic data to detect circulating tumor DNA (ctDNA) in blood samples. Once identified, the ctDNA is compared to a database of genetic information from hundreds of people to identify where the tumor is located.  Zhou’s team discovered that tumors, which arise in different parts of the body, have different signatures, which a computer can spot. “The technology is in its infancy and requires further validation, but the potential benefits to patients are huge  . . . . . Non-invasive diagnosis of cancer is important, as it allows the early detection of cancer, and the earlier the cancer is caught, the higher chance a patient has of beating the disease,” says Zhou.
 
The Nature Genetics study

Researchers led by Kun Zhang, Professor of Bioengineering at the University of California, San Diego (UCSD), are responsible for the study published in the journal Nature Genetics. Zhang developed a test that examined ctDNA in blood from cancer patients and, like Zhou, discovered that not only could it detect cancer early, but could also locate where the tumor is growing in the body. When a tumor starts to take over a part of the body, it competes with normal cells for nutrients and space, killing them off in the process. As normal cells die, they release their DNA into the bloodstream; and that DNA can identify the affected tissue.
 
There are many technical differences on how each approach works . . . The work by the UCLA group is a computer program that uses data published previously by other groups, and has reduced the cancer detection error from roughly 60% to 26.5%. In contrast, we developed a new theoretical framework, generated our own data from over 100 patients and healthy people, and our accuracy of locating cancer in an organ is around 90%,” says Zhang, but he adds, “Major medical challenges don’t get solved by one team working alone”.
 
Confluence and advances in computing and biology

The research endeavors of Professors Zhou and Zhang have been made possible by the confluence and advances in computing and molecular biology. Over the past 20 years, there has been a paradigm shift in biology, a substantial increase in computing power, huge advances in artificial intelligence (AI), and the costs of data storage have plummeted. It took 13 years, US$3bn, and help from 7 governments to produce the first map of the human genome, which was completed in 2003. Soon it will be possible to sequence an entire genome in less than an hour for US$100.
 
The end of traditional in vitro diagnostics

Liquid biopsies are a sequencing-based technology used to detect microscopic fragments of DNA in just a few drops of blood, and hold out the potential to diagnose cancers before the onset of symptoms. Roger Kornberg, Professor of Structural Biology at Stanford University, and 2006 Nobel Laureate for Chemistry for his work in understanding how DNA is converted into RNA, “which gives a voice to genetic information that, on its own, is silent,” describes how advances in molecular science are fueling the replacement of traditional in vitro diagnostics with virtually instantaneous, point-of-care diagnostics without resort to complex processes or elaborate and expensive infrastructure. Liquid biopsies, such as those developed by Zhou and Zhang, have the potential to provide clinicians with a rapid and cheap means to detect cancer early, thereby enabling immediate treatment closely tailored to each patient’s disease state.

 
 
FDA approval of liquid biopsy
 
In 2016, the US Food and Drug Administration (FDA) granted Swiss pharmaceutical and biotech firm Roche approval for a liquid biopsy, which can detect gene mutations in the most common type of lung cancer, and thereby predict whether certain types of drugs can help treat it. 

The clinical implementations of such a test are not widespread, and there has been no regulatory approval of liquid biopsies for diagnosing cancer generally. Notwithstanding, ctDNA is now being extensively studied, as it is a non-invasive “real-time” biomarker that can provide diagnostic and prognostic information before and during treatment; and at progression.
 

cfDNA and ctDNA

Cell-free DNA (cfDNA) is a broad term that describes DNA, which is freely circulating in the bloodstream, but does not necessarily originate from a tumor. Circulating tumor DNA (ctDNA) is fragmented DNA, which is derived directly from a tumor or from circulating tumor cells (CTCs).
 
Commercialization of the liquid biopsy race
 
Bill Gates, Jeff Bezos and leading venture capitalists have poured hundreds of millions into the goal of developing liquid biopsies. The US market alone is projected at US$29bn, according to a 2015 report from investment bank Piper Jaffray. Currently, there are about 40 companies in the US analyzing blood for fragments of DNA shed by dying cancer cells. Notwithstanding, only a few companies have successfully marketed liquid biopsies, and these are limited to identifying the best treatments for certain cancers, and to update treatments as the cancer mutates. So far, no one has been successful in diagnosing incipient cancer from a vial of blood drawn from a patient who looks and feels perfectly healthy.
 
Some US companies in the liquid biopsy race

At the 2016 meeting of the American Society of Clinical Oncology (ASCO), a Silicon Valley start-up, Guardant Health, which has raised some US$200m, presented findings from a large study involving over 15,000 participants, which demonstrated the accuracy of its liquid biopsy test, Guardant360, for patients with advanced solid tumors. The study found the same patterns of genomic changes in cfDNA reported by the Guardant360 test as those found in 398 patients with matching tissue samples between 94% and 100% of the time.

The 70-gene test is the first comprehensive, non-invasive genomic cancer-sequencing test to market, and according to the company, about 2,000 physicians worldwide have used it. Guardant expects to continue to develop its technology, and maintain a commercial lead in the cfDNA liquid biopsy space. The next step for Guardant is to go beyond sequencing, which matches patients to targeted oncology drugs to the early detection of cancer itself. 
 
Also in 2016 Gates and Bezos teamed up with San Diego's Illumina, which makes most of the DNA sequencing machines that pick appropriate treatments for cancer patients, to launch another liquid biopsy start-up called Grail. In 2017, Grail raised US$900m to help it develop blood-based diagnostics to enable routine, early detection of cancer. The company aims to refine and validate its liquid biopsy technology by running a number of large-scale clinical studies where it expects to sequence hundreds of thousands of patients. Another Californian-based biotech start-up, Freemome,  raised US$65m to validate its liquid biopsy technology for the early detection of cancer.
 
Takeaways

Despite findings of the two 2017 studies reported in the journals Genome Biology and Nature genetics, FDA approval of Roche’s liquid biopsy, massive increase in investment, and significant commercial biotech activity, there is a gap between reality and aspirations for liquid biopsies. To provide doctors with a reliable, point-of-care means to detect cancer early, liquid biopsies will have to overcome several significant challenges. The major one is assay sensitivity and specificity for analysis of ctDNA and cfDNA. To compete with the gold standard solid tissue biopsy, and to ensure that patients receive early diagnosis and appropriate treatment, a successful liquid biopsy assay will have to demonstrate a high positive predictive value. Concomitantly, good sensitivity and excellent specificity will be required to yield acceptable rates of false positives and false negatives. Notwithstanding, the race among bioengineers to develop a non-invasive “real-time” liquid biopsy to detect cancer early is gaining momentum.
 

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  • Stem cell study aims to improve prospects for lung cancer sufferers
  • Professor Sikora suggests that lung cancer is associated with poverty
  • Current therapies for lung cancer extend life by only a few months
  • Lung cancer kills more people than any other cancer

Lung cancer and cutting edge stem cell therapy

In 2015 a combined stem cell and gene therapy for lung cancer started its first clinical study in the UK. Professor Sam Janes of University College London, the study’s leader, said: “This will be the first UK cell therapy for lung cancer, and the biggest manufacturing of cells of its kind.” 

Dr Chris Watkins, director of translational research at the Medical Research Council, which is funding the study, said: “Lung cancer kills more men and women than any other cancer, and improving the outcome for patients with this terrible disease is one of the biggest challenges we face. This new therapy, which uses modified stem cells to target the tumour directly is truly at the cutting edge.”

 
Few studies
 
The use of stem cells for treating lung diseases has increasing appeal, but as yet, little is known about the effects of administering stem cell therapy to patients with lung diseases. Currently, there are only a small number of approved clinical studies in the US and Canada investigating cell therapy approaches for lung diseases. Patrick O’Brien a consultant obstetrician and gynaecologist at University College Hospital, London describes an initiative to create a national stem cell bank in the UK: 
 
       
 
Lung cancer
 
Lung cancer is the most common cancer worldwide, accounting for 1.8 million new cases and 1.6 million deaths in 2012. This year, an estimated 224,210 adults in the US, 40,000 in the UK, and 169,000 in India will be diagnosed with lung cancer, 90% of which are and caused by smoking. Of those diagnosed, 95% will die within ten years, although early stage lung cancer has a much better survival rate. Professor Karol Sikora, a world respected oncologist, and campaigner for better universal cancer treatment, suggests that lung cancer is associated with poverty:
 
    

Traditional therapies
 
Cell-gene therapy holds out new hope. “Lung cancer is very difficult to treat because the vast majority of patients are not diagnosed until the cancer has spread to other parts of the body. One therapy option for these patients is chemotherapy, but even if successful this treatment can normally only extend lives by a handful of months,” says JanesCurrent therapeutic strategies of chemotherapy, radiation therapy, and clinical studies with new-targeted therapies have only demonstrated, at best, extension in survival by a few months.
 
Innovative approach
 
“We aim to improve prospects for lung cancer patients by using a highly targeted therapy using stem cells, which have an innate tendency to home in on tumours when they’re injected into the body. Once there, they switch on a ‘kill’ pathway in the cancer cells, leaving healthy surrounding cells untouched,” says Janes. His study will test the treatment in human volunteers, firstly to check that the treatment is safe, and then in 56 lung cancer patients to see how effective the gene-cell therapy compares with standard care. Each patient in the study will receive three infusions comprised of billions of cells in parallel with chemotherapy.
 
Takeaways

A key advantage of Janes’ proposed treatment is that the cells do not have to be closely matched to a person’s tissue type or genetic profile. They are simply taken “off the shelf” from existing bone marrow supplies. This is because the cells have relatively few proteins on their surface, and do not induce an immune response in the recipient.
 
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Clinical study challenges off-label use of targeted cancer therapies

  • Oncologists increasingly use targeted agents directed at molecular features of cancer cells
  • There is increased off label use of these new targeted agents without evidence to support the practice
  • A landmark study concludes that off label use of targeted agents show no benefit and should be discouraged
  • Professor Gabra, head of cancer at Imperial College, says more research is needed
 

Despite significant progress in cancer care over the past decade, there remain substantial challenges in the treatment of advanced cancers. This has increased off-label use of newer drugs based on molecular studies of tumours, largely without much evidence to support the practice.

A landmark clinical study, known as SHIVA, led by Christophe le Tourneau, a senior medical oncologist at the Institut Curie in Paris, raised expectations among both doctors and patients, because it is one of the first randomized studies to explore molecularly targeted agents applied outside their indicated use (off-label) among those with advanced cancers for whom standard therapies had failed.
 
Findings, published in Lancet Oncology, September 2015, concluded that, “off-label use of molecularly targeted agents should be discouraged,” since the study detected no improvement in survival rates when compared to treatments selected by clinicians that were not based on such sophisticated DNA profiling. 

What are the implications of the study’s negative findings for personalised medicine?

Christophe le Tourneau

In the videos below Le Tourneau describes the SHIVA trail and some of the challenges it faced.

   

   
     (click to play the video) 

 

The context

Cancer is a heterogeneous, complex, and challenging disease to treat. Tumours formerly categorized as a single entity on the basis of microscopic appearance are now known to be diverse in their molecular characteristics. Cancer chemotherapy is on an evolutionary path from non-specific cytotoxic drugs that damage both tumour and normal cells to targeted agents that are directed at unique molecular features of cancer cells, and aims to produce greater effectiveness with less toxicity.
 
Over the past decade our understanding of cancer and the basis of its treatment has been significantly changed by the advent of rapid and cheap DNA sequencing technology. The application of these sophisticated analytic techniques to arrive at a therapy for a particular cancer has been called “personalized oncology.” The idea of personalized cancer care based on molecular characteristics of the tumour promises to expand the boundaries of precision medicine. Numerous case reports and other observations have suggested that therapy targeted at molecular characteristics of a tumour can have significant beneficial effects.
 
These personalized therapeutic strategies have rendered traditional classifications of many cancers redundant, because they have advanced our understanding of the underlying biology and molecular mechanisms of specific cancers. Cancer is no longer considered a single disease entity, and is now being subdivided into molecular subtypes with dedicated targeted and chemotherapeutic strategies. The concept of using information from a patient's tumour to make therapeutic and treatment decisions has changed the landscapes of both cancer care and cancer research.

 

The SHIVA study

The SHIVA study, carried out at eight academic centres in France and conducted in 195 patients with metastatic cancer resistant to standard care, was a proof-of-concept, open-label, randomized controlled study. The patients were randomly assigned to receive either molecularly targeted agents (used off-label) chosen on the basis of the molecular profile of the tumour; or therapy based on the clinician's choice. The median follow-up period was 11.3 months. Findings showed a median progression free survival (PFS) of 2.3 months for patients receiving targeted therapy, versus 2.0 months for patients receiving therapy based on the clinician's choice.

"So far, no evidence from our randomised clinical trial supports the use of molecularly targeted agents outside their indications on the basis of tumour molecular profiling . . . . . Our findings suggest that off-label use of molecularly targeted agents outside their indications should be discouraged, and enrolment into clinical trials encouraged," says Le Tourneau and his colleagues.
 

More research required

Hani Gabra, Professor of Medical Oncology and Head of Cancer, Imperial College London says, "SHIVA is important because it is the first randomized study carried out in this complex area of matching drugs to genomic profiles of tumours. Despite the fact that the results are negative we should continue research in this area because personalised medicine is a relatively new area. One thing to note is that the molecularly targeted agents used in SHIVA were single agents, which could increase resistance and reduce the agent’s efficacy. In clinical practice we tend to use several targeted agents in combination in order to counteract drug resistance. SHIVA tested specific agents and specific targets, which resulted in disappointing findings. This doesn’t necessarily negate the overall strategy, but it does suggest that more research is necessary to test the overall strategy, and this might be more challenging.”
 

Takeaways

SHIVA is one of several on going and proposed studies aimed at defining the role of targeting sequencing of tumours in an endeavour to enhance therapy. The SHIVA study did not uncover any new positive evidence to help in the management of advanced cancers. Le Tourneau and his colleagues suggest further studies in a subset of patients that have tumours with molecular alterations in the chain of proteins in the cell that communicates a signal from a receptor on the surface of the cell to the DNA in the nucleus of the cell. Oncologists, while disappointed by SHIVA’S results, still hold out hope for their patients and advocate further studies.

 
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A new test, called ADNEX, reported in the British Medical Journal in October 2014 helps to identify different types and stages of ovarian cancer more accurately, which scientists claim will reduce the incidences of unnecessary surgeries.

Accurate, simple and ready
The test, developed by an international team led by Imperial College London and KU Leuven, Belgium, is based on patient data, a simple blood test, and features that can be identified on an ultrasound scan. Doctors can use it simply by entering patient data into a smartphone app. It’s highly accurate, and discriminates between benign and malignant tumours, and also identifies different types of malignant tumours.

Successful treatment depends on accurate diagnosis, and diagnosis of ovarian cancer can be challenging. According to Professor Tom Bourne, Department of Surgery and Cancer at Imperial College London, "The way we assess women with ovarian cysts for the presence of cancer and select treatment lacks accuracy. This new approach to classifying ovarian tumours can help doctors make the right management decisions, which will improve the outcome for women with cancer. It will also reduce the likelihood of women with all types of cysts having excessive or unnecessary treatment that may impact on their fertility."

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Cancer research and cancer treatment are evolving very rapidly. Built on a platform of intensive molecular research, the prognosis of cancer is beginning to be transformed. We have huge amounts of cancer information at our disposal. The challenge is how to translate these into the clinic and make cost effective treatments. 

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