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  • CanRisk is a new online gene-based health-risk evaluation algorithm for detecting breast cancer
  • It identifies people with different levels of risk of breast cancer, not just those at high risk
  • As the infotech and biotech revolutions merge expect authority in medicine to be transferred to algorithms
  • CanRisk has the potential to provide a cheap, rapid, non-invasive, highly sensitive and accurate diagnosis before symptoms present
  • Breast cancer is the most common cancer in women worldwide and is the 5th most common cause of death from cancer in women
  • Currently mammography screening, which has a sensitivity between 72% and 87%, is the gold standard for preventing and controlling breast cancer
  • For every death from breast cancer that is prevented by screening, it is estimated there will be three false-positive cases that are detected and treated unnecessarily
  • Lack of resources do not support breast cancer screening in many regions of the world where the incidence rates of the disease are rapidly increasing
  • In the near-term expect interest in the CanRisk algorithm to increase
 
 A new comprehensive gene-based breast cancer prediction device

 
A new online gene-based health-risk evaluation device called CanRisk has the potential to identify women with different levels of risk of breast cancer; not just women who are at high risk. Predicated on a comprehensive algorithm, CanRisk is one of several innovations currently in development, which include novel methods for predicting the recurrence of breast cancer, a new class of molecules that aim to halt or destroy breast cancer, and liquid biopsies, which determine the presence and recurrent risk of the disease through the detection of tumour cells in peoples’ blood.
 
Although over the past two decades there have been significant improvements in the detection and treatment of breast cancer, the disease remains the most common cancer in women worldwide, with some 1.7m new cases diagnosed each year, which account for about 25% of all cancers in women and it is the fifth most common cause of death from cancer in women, with over 0.52m deaths each year.
 
Game changer for breast cancer
 
Findings of CanRisk were reported in the January 2019 edition of Genetics in Medicine. Findings of a less comprehensive version of the device’s algorithm were published in the July 2016 edition of the same journal. Commenting on the 2019 study, Antonis Antoniou, Professor of Cancer Risk Prediction at the University of Cambridge and lead author of the two studies said: "This is the first time that anyone has combined so many elements into one breast cancer prediction tool. It could be a game changer for breast cancer and help doctors to tailor the care they provide depending on their patients' level of risk”.
 
When fully developed and approved, CanRisk will be well positioned to provide a cheap, rapid, non-invasive, highly sensitive and accurate diagnostic test to detect breast cancer early in people with diverse levels of risk. This might be expected to provide an alternative to the current gold standard population-based mammography screening and assist in making a significant dent in the vast and escalating global burden of the disease.
 
In this Commentary
 
This Commentary describes the algorithm that drives CanRisk, which benefits from the increasing availability of vast and growing amounts of genomic and other personal data and significant advances in genomic sequencing technologies. The confluence of these two phenomena facilitates and enhances the quality and speed of data analysis and drives the development of new and innovative diagnostic and prognostic cancer technologies. The fact that CanRisk is based on UK data and its algorithm is available to researchers globally, presents a potential  opportunity for medical research organizations in emerging regions of the world where the burden of breast cancer is increasing. The Commentary briefly describes the heterogeneous nature of breast cancer and highlights some of its complexities and risk factors. Originally perceived as a Western disease, breast cancer is growing rapidly in Asia and other regions of the world where it tends to be detected late and managed less effectively. Developed economies prevent and manage breast cancer through well-established population-based mammography screening programs. Because of  the lack of resources,  such screening programs are not widely available in low to middle income countries (LMIC). As the infotech and biotech revolutions merge expect authority in medicine to be transferred to Big Data algorithms such as CanRisk. This not only could provide an alternative to gold standard mammography screening, but also provide a cheap and effective device for use in developing nations where the burden of breast cancer is significant and increasing.
 
CanRisk: a world first
 
CanRisk, developed by members of the Centre for Cancer Genetic Epidemiology at the University of Cambridge, UK, takes advantage of discoveries in both cancer genomics and epidemiology and aims to become a popular device used by primary care physicians, in consultation with their patients, to effectively assess patients’ diverse levels of risk of developing breast cancer. The device is predicated on an algorithm called BOADICEA (the Breast and Ovarian Analysis of Disease Incidence and Carrier Estimation Algorithm). This is the world’s first polygenic breast cancer risk model and the only one to-date, which is available to the international research community. Also, it is the first breast cancer risk model to incorporate pathology data and population-specific cancer incidences in risk calculations. The algorithm accounts for over 300 genetic risk factors, including BRCA1, [BReast CAncer gene] BRCA2PALB2CHEK2, and ATM, which are genes that have been found to impact a person’s chances of developing breast cancer. The device uses a Polygenic Risk Score (PRS) based on 313 single-nucleotide polymorphisms (SNPs), [SNPs, pronounced ‘snips’, are the most common types of genetic variation in people. Each SNP represents a difference in a single DNA building block and is called a nucleotide] which explains 20% of breast cancer polygenic variance. CanRisk also includes a residual polygenic component, which accounts for other genetic/familial effects; known lifestyle/hormonal/reproductive risk factors and mammographic density [Dense breast tissue can make it harder to evaluate mammographic results and may also be associated with an increased risk of breast cancer].

 

Authority increasingly being transferred to algorithms
 
Over the past two decades we have increasingly learnt to accept the authority of Big Data algorithms. For example, without question we expect algorithms to give us directions, tell us what movies to watch, who to date, what clothes to wear, where to go on holiday, what flight to take, what hotel to stay in and where to eat. We are  comfortable with algorithms assigning us our credit rating, limiting our overdraft and capping our payments. Furthermore, we are beginning to accept the authority of algorithms in medicine. For example, we are gradually replacing the authority of primary care doctors with algorithms that can diagnose common diseases more accurately and more cost effectively.


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China’s rising MedTech industry and the dilemma facing Western companies

In December 2018, for the first time in history, the US FDA approved an algorithm to diagnose patients without a doctor’s interpretation. The algorithm, called IDx-DR, detects diabetic retinopathy by analysing images of the back of the eye. Indeed, we are living on the cusp of history when the twin revolutions of information technology and biotechnology are merging and providing the basis for us to transfer authority in medicine to algorithms. In the next two decades, it seems reasonable to assume that it will become common practice to accept the authority of algorithms such as CanRisk, which will inform us that we are suffering from a medical condition long before we present any signs or symptoms.
 
Increasing supply of data
 
CanRisk takes advantage of the fact that genetic and other risk factor data are becoming more easily available in clinical practice through electronic health records, biometric sensors that convert biological processes into electronic information, which computers can store and analyse, cost-effective high speed, high capacity genomic sequencing technologies, and efforts such as the 100,000 Genomes ProjectA UK Government sponsored initiative completed in December 2018, which collected, stored and analysed data from the genomes and medical records of 85,000 NHS England patients affected by cancer or rare disease. Genomics Englandwhich is wholly owned by the UK’s Department of Health, was set up in 2003 to deliver the project. Because CanRisk solely is based on UK population data, its findings are likely to be more applicable to similarly developed Western populations, and less so to populations in other regions of the world. This provides a potential opportunity for international organizations interested in early breast cancer diagnosis. 
 
International sequencing projects
 
The UK’s genomes project is part of a much larger rapidly growing and dynamic global genomics market comprised of data and gene sequencing technologies. 100,000 genomes have been the goal of several other nations interested in improving their healthcare - and lowering costs  - by carrying out precision medicine based on insights from sequencing data. Currently the global genomics market is estimated to be about US$19bn and projected to reach US$41bn by 2025. The market is driven by increasing government funding, the consequent rise  in the number of genomics projects, decreasing gene sequencing costs, growing application areas of genomics and the entry and fast growth of commercial players.

China has become the world’s leader in genomic sequencing. In 2010, the Beijing Genomics Institute (BGI) in Shenzhen was understood to be hosting a higher sequencing capacity than that of the entire US. While most government projects aim to sequence 100,000 genomes, China’s sequencing program is set to sequence 1m human genomes, which include subgroups of 50,000 people, each with specific conditions such as cancer or metabolic disease. The data will also include cohorts from different regions of China, which will facilitate “the analysis of different genetic backgrounds of subpopulations”.
 

Revolution in genome sequencing
 
The first human genome project began in 1990, took 13 years and about US$1bn to complete. The last two decades have seen a revolution in genome sequencing with dramatic increases in its speed and efficiency coupled with massive reductions in cost. Genomic sequencing has proved its usefulness as a diagnostic and prognostic tool. Today it is possible to get your genome sequenced for around US$1,000 in a few days and delivered by  post from firms such as Dante Labs and 24 Genetics in Europe, and Veritas Genetics and Sure Genomics in the US.
 
Breast cancer
 
Returning to breast cancer. It is important to note that the disease is not one, but  a group of conditions that manifest themselves with maladies in the same organ. Breasts are comprised of three main parts: lobules, which produce milk; ducts, which carry milk to the nipples; and fibrous and fatty connective tissue, which hold everything together. The type of breast cancer depends on which cells in the breast mutate, but most breast cancers begin in the ducts or lobules. Some mutated cells in the breast may never spread, however, most breast cancers tend to be invasive and may present with a number of different characteristics in terms of hardness and shape, which can provide some indication of their likely progression. Breast cancer can spread outside the breast through blood and lymph vessels. Further, there are significant differences in breast cancer at the genetic level. A study published in the April 2012 edition of Nature compared the genetic makeup of breast cancer tumour samples with their other characteristics for some 2,000 women, for whom information about the tumour characteristics had been meticulously recorded; and identified at least 10 distinct sub-types of breast cancer, each with its own unique characteristics. Although the study contributed to how breast cancer is diagnosed, classified and treated, in practice certain characteristics of these tumours were already known and tested for: most notably cellular receptors for estrogen, and progesterone, which are the two most significant steroid hormones responsible for various female characteristics. Their presence or absence generally suggests the potential utility of additional medication to accompany surgery, radiotherapy and chemotherapy.

 
Despite population screening and advanced therapies breast cancer remains a killer disease
 
Let us briefly consider breast cancer in the world’s most advanced and wealthiest nation: the US. Although there have been significant improvements in the detection and treatment of breast cancer in the US; still about 1 in 8 American women will develop an invasive type of the disease over the course of her lifetime. In 2019, an estimated 268,600 new cases of invasive breast cancer are expected to be diagnosed in the US, along with 62,930 new cases of non-invasive (in situ) breast cancer. Breast cancer death rates for women in the US are higher than those for any other cancer, besides lung cancer. As of January 2019, there were more than 3.1m women with a history of breast cancer in the US. Although breast cancer death rates in the US have been decreasing over the past three decades and women under 50 have experienced larger decreases, still some 41,760 are expected to die in 2019 from the disease. About 2,670 new cases of invasive breast cancer are expected to be diagnosed in men in the US in 2019 where a man’s lifetime risk of breast cancer is about 1 in 883.
 
Breast cancer challenges in Singapore
 
There are also breast cancer challenges in wealthy non-Western developed economies such as Singapore. Over the past four decades, the incidence of breast cancer in Singapore has more than doubled: from 25 to 65 per 100,000 women. Breast cancer is not just the most common cancer for Singaporean women, accounting for one in three cancers in women, but it is also the top killer. Data reported in the country’s Cancer Registry showed that 2,105 women died of the disease between 2011 and 2015. Notwithstanding, Singapore has extensive awareness-raising programs; population-wide mammography screening; excellent, multi-disciplinary primary and long-term care and improving palliative care, which have contributed to a significant increase in the survival rates of breast cancer patients. However, a substantial proportion of Singaporean women still appear to have a patchy knowledge of aspects of the disease, which leads to comparatively low participation rates in the nation’s breast cancer screening services, and this contributes to late presentation of the disease when it is more difficult to cure and more challenging to treat.

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Breast cancer and harmful BRCA gene mutations


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Breast cancer growing rapidly in Asia
 
Breast cancer was once largely confined to developed Western countries and Australasia, but it has now become the most common cancer in Asia. Although Asian data on breast cancer are patchy, an Economist Intelligence Unit report, suggests that, “since the 1990s, increases in the incidence of breast cancer in Asia, as measured by age-standardised rates (ASRs), is four to eight times that of the global average”. Indeed, as younger cohorts of Asian women age and adopt Western diets and lifestyles (particularly fertility patterns, such as later first childbirth and shorter breast feeding), breast cancer incidence rates in Asia look set to converge with the much higher ones in the West.
 Further, in LMIC breast cancer is increasing at a more rapid rate than in the West and has become a significant healthcare challenge: 50% of breast cancer cases and 58% of deaths from the disease occur in LMIC.
 The significance of early detection
 
The good news is that if caught in its early stages, breast cancer can be treated effectively, with high survival rates. The average 5-year survival rate for women with invasive breast cancer is 90%. The average 10-year survival rate is 83%. If the cancer is located only in the breast, the 5-year survival rate of women with breast cancer is 99%. In all types of the disease early detection is the cornerstone of breast cancer control.
 
 Gold standard breast cancer mammography screening
 
The current gold standard for preventing and controlling breast cancer is population-based mammography screening. This is a non-invasive process that uses an x-ray of the breast to look for disease in women who do not have symptoms. The method has reasonable sensitivity (72%–87%) that increases with age and allows for the early detection of breast cancer, which helps increase survival, especially in women between 50 and 70. Notwithstanding, mammograms are not pleasant as the breast is squashed between two metal plates and further some women may find mammograms embarrassing.
 
Success of population-based mammography screening
 
Following a landmark Swedish study that began in 1977 mammography screening has been adopted in more than 26 developed countries worldwide. Findings of the study, reported in a 1989 edition of the Journal of Epidemiology and Community Health, suggested that mortality from breast cancer dropped 31% after screening of women aged 39 to 74. More recent findings of the UK screening program published in the June 2013 edition of the British Journal of Cancer, suggested mortality rates from breast cancer were reduced by 20% in the screened group compared to the unscreened group across all age groups. A study published in 2018 in Cancer, which tracked 52,438 Swedish women aged 40-69 from 1977 to 2015, suggested that regular mammograms contributed to a 60% decrease in breast cancer death during the first 10-years of diagnosis, and a 47% reduced risk within 20-years. Research has shown that mammography has relatively little benefit for women under 50.
 
Diverging views about mammography screening
 
Despite evidence to support the benefits of population-based mammography screening, there are diverging views among healthcare professionals about the impact of several decades of high levels of screening. Some argue that traditional mammography screening stretches finite resources and is not cost-effective because the majority of people who undergo screening do not have cancer and may never go on to develop it. Others suggest that there are significant uncertainties about the magnitude of the harms from mammography screening especially associated with false positives (a test result, which wrongly indicates that breast cancer is present).

Challenges of mammography screening
 
The sensitivity of mammography is between 72% and 87%, but is higher in women over 50 and in women with fatty rather than dense breasts. Dense breast tissue can make it harder to evaluate results of a mammogram. According to the Marmot review, for every death from breast cancer that is prevented by screening, it is estimated there will be three over-diagnosed or false-positive cases that are detected and treated unnecessarily. The chance of having a false positive result after one mammogram ranges from 7% to 12%, depending on age (younger women are more likely to have false positive results). After 10 yearly mammograms, the chance of having a false positive is about 50-60%. The more mammograms a woman has, the more likely it is she will have a false positive result. This makes it difficult for doctors to weigh and communicate the benefits and risks of mammography screening programs and fuels interest in innovations such as CanRisk.
 
Takeaways
 
Mammography screening for breast cancer is not 100% accurate. Further, knowhow, trained healthcare professionals and significant resources are required to effectively implement and manage a well-organized and sustainable breast cancer screening program that targets the right population group and ensures effective coordination and quality of actions across the whole continuum of care. These attributes tend to exist only in developed wealthy countries. CanRisk, and other innovative breast cancer early diagnostic devices under development, offer the potential for cheap, rapid, reliable and exquisitely accurate diagnosis that can be easily used in primary care settings throughout the world. In time, as authority in medicine passes to algorithms, expect these new and innovative devices to replace mammography screening in wealthy countries and quickly become devices of choice in developing economies and significantly dent the vast and rapidly growing global burden of breast cancer.
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  • Each year about 1.7m women are diagnosed with breast cancer worldwide and over 0.5m die from the condition
  • Between 5% and 10% of these breast cancers result from harmful gene mutations
  • BRCA1 and BRCA2 gene mutations are the most common cause of hereditary breast cancer
  • 45% to 85% of women with a BRCA mutation will develop breast cancer in their lifetime compared to 12% of women in the general population
  • Most women do not know if they have a harmful BRCA mutation
  • Testing for the BRCA gene is now affordable, fast and accessible
  • Surgical interventions of women with BRCA mutations can significantly reduce their risk of developing breast cancer and substantially increase cancer survival
  • Genetic test results for breast cancer are fraught with uncertainty because testing reveals the likelihood of developing cancer rather than a certain fate
  • Research suggests that BRCA test results are not being clearly communicated to women
  • Best practice demands that expert counselors discuss genetic testing and help interpret results
 
Breast cancer and harmful BRCA gene mutations


Few things frighten women more than discovering a lump in one of her breasts The standard treatment: surgery, followed by radio- and chemotherapy, can be disfiguring, painful, sometimes unsuccessful, and the impact of the disease is felt by far more individuals than just those who have the diagnosis.The good news is that over the past 30 years breast cancer survival rates in most developed countries have been improving, largely due to screening, earlier diagnosis and improved treatments. The bad new is that in most developed countries it is twice as likely for a woman to be diagnosed with breast cancer than 60 years ago.
 
Harmful BRCA genes mutations

5 to 10% of breast cancers are thought to be due to gene mutations, and harmful BRCA mutations account for 20 to 25% of these. Women who inherit the BRCA1 mutations have a 60 to 90% risk of developing breast cancer in their lifetime, and those who inherit BRCA2 mutations increase their risk of breast cancer by 45 to 85%, compared to 12% of women in the general population. Most women do not know if they carry the harmful BRCA mutation, but if they discover they do, many elect to have a bilateral mastectomy. This is a significant procedure with potential risks and side effects, but can reduce your mortality risk by about 50%.
 
The gold standard screening for breast cancer is an x-ray picture of the breast (mammography), but increasingly women are turning to genetic testing as their awareness of the harmful BRCA mutations increase, and genetic testing becomes more accessible and affordable. However, results from these tests are not straightforward, and often not communicated well. This can increase the anxiety in women with suspected breast cancer, and make them elect to have unnecessary interventions and procedures.
 
This Commentary describes how advanced genetic testing together with expert counselling help women improve their management of breast cancer.
 

Breast Cancer
 
Cancer is a group of diseases that cause cells in your body to change and grow out of control: they mutate. Most types of cancer cells eventually form a lump or mass called a tumor, and are named after the part of the body where the tumor originates, e.g. “breast cancer”, although this convention is changing with the development of targeted personalized medicine. The exact cause of breast cancer is unknown, but the overwhelming majority result from some combination of environment, lifestyle, and genes. Breast cancer affects about 1 in 8 women at some point during their life, usually after the menopause, and is the most common cancer in women.  The majority of breast cancers begin in the parts of the breast tissue that are made up of glands for milk production, called lobules, and ducts that connect the lobules to the nipple. The remainder of the breast is made up of fatty, connective, and lymphatic tissue. Most invasive breast cancers (those that have spread from where they started) are found in women 55 and older. Women with a family history of the disease have an increased risk of getting breast cancer. Each year about 1.7m women are diagnosed with breast cancer worldwide, and over 0.5m die from the condition. However in developed economies more and more women survive the disease. In the US, for instance, the average 5-year survival rate for people with breast cancer is 89%. The 10-year rate is 83%, and the 15-year rate is 78%. Other developed countries have similar success rates. What makes breast cancer fatal is if it spreads to the bones, lungs, liver and other organs. Early detection in order to improve breast cancer outcomes remains the cornerstone of the condition’s management. Although breast cancer is thought to be a disease of the developed world, it is increasing rapidly in emerging countries where the majority of cases present later and die earlier than women in developed countries: almost 50% of breast cancer cases and 58% of deaths occur in emerging economies. This is because women generally have relatively poor knowledge of the risk factors, symptoms and methods for early detection. Also, they experience cancer fatalism, believe in alternative medicine, and lack of autonomy in decision making, which often results in delays in seeking or avoidance of evidence-based medicine.
 
Mammography
 
Mammography, which has long been the mainstay of breast cancer detection, is a specific type of breast imaging that uses low-dose x-rays to detect small changes in the breast before there are any other signs or symptoms of the disease when it is most treatable. Mammography is noninvasive, relatively inexpensive, and has reasonable sensitivity (72–88%), which increases with age. It can also be used to detect and diagnose breast disease in women experiencing symptoms such as a lump, pain, or nipple discharge. If breast cancer is found at an early stage, there is an increased chance for breast-conserving surgery and a better prognosis for long-term survival. Most developed countries operate breast-screening programs, which regularly provides mammography for women between certain ages.
 
Advances in mammography

In recent years, mammography has undergone increased scrutiny for false positives and excessive biopsies, which increase radiation dosage, cost and patient anxiety. In response to these challenges, new forms of mammography screening have been developed, including; low dose mammography, digital mammography, computer-aided detection, tomosynthesis, which is also called 3-D mammography, automated whole breast ultrasound, molecular imaging and MRI. Notwithstanding, there is increasing awareness of subpopulations of women for whom mammography has reduced sensitivity. More recently, women have turned to genetic testing to gain a better understanding of their risk of inherited breast cancer.
 
Genes

Every cell in your body contains genes. These contain the genetic code for your body, which not only determines the color of your eyes and hair etc., but also provides information that affects how the cells in your body behave: for example, how they grow, divide and die. Information in your genes is inherited from both parents, and you pass on this information to your children. A change in your genetic code that affects the function of a gene is called a mutation. Many inherited gene mutations do not have any effect on your health, but some do; the BRCA1 and BRCA2 mutations account for 20 to 25% of all inheritable female breast cancers and 15% of ovarian cancers.
  
BRCA genes

In normal cells, BRCA genes are tumor suppressor genes that assist in preventing cancer developing by making proteins that help to keep cells from growing abnormally. Mutated versions of BRCA genes cannot stop abnormal growth, and this can lead to cancer. Mutated BRCA genes have a higher prevalence in certain ethnic groups, such as those of Ashkenazi Jewish descent.

In the video below Professor Robert Leonard, a medical oncologist and an authority on breast cancer, describes how BRCA genes are influential in breast and ovarian cancer risk. BRCA1 runs in families and may also increase a woman’s risk of developing fallopian tube and peritoneal cancers. BRCA2 also runs in families, and is more breast cancer-specific, but a less commonly inherited abnormality. Both or either of these genes may not be detectably abnormal even in a family with a strong inherited pattern of breast cancer, but there is a significant possibility that you will find them in people with a family history of breast and ovarian cancer. Breast and ovarian cancers associated with BRCA mutations tend to develop at younger ages than their non-hereditary counterparts.

 
 
Enhanced risk when family members have cancer
 
In December 2013, the US Preventive Services Task Force recommended that women who have family members with breast, ovarian, fallopian tube, or peritoneal cancer be evaluated to see if they have a familial history that is associated with an increased risk of a harmful mutation in one of the BRCA genes. Compared to women without a family history of cancer, risk of breast cancer is about 2 times higher for women with a close female relative who has been diagnosed with cancer; nearly 3 times higher for women with two relatives, and nearly 4 times higher for women with three or more relatives. Risk is further increased when the affected relative was diagnosed at a young age. Notwithstanding, the Preventive Services Task Force recommends against BRCA testing for women with no family history of cancer.
  
The Angelina Jolie effect

The Hollywood actress and filmmaker Angelina Jolie lost her grandmother and aunt to breast cancer and her mother to ovarian cancer. After discovering that she carried a maternally inherited pathogenic BRCA1 mutation, and being told that she had an 87% chance of developing breast cancer, and a 50% chance of ovarian cancer, Jolie elected to have her breasts, ovaries and fallopian tubes removed. After surgery her risk of developing breast cancer in later life fell to 5%.
 
In May 2013, Jolie described her decision in a New York Times (NYT) article,  “I am writing about it now because I hope that other women can benefit from my experience . . . . . Cancer is still a word that strikes fear into people’s hearts, producing a deep sense of powerlessness. But today it is possible to find out through a blood test whether you are highly susceptible to breast and ovarian cancer, and then take action.”
 
Over testing of by low-risk women
 
Findings published in December 2016 in the British Medical Journal suggest that tests for the BRCA genes shot up by 64% following Jolie’s article. Researchers analysed data on US health insurance claims from more than 9m women between 18 and 64, and suggested that in just 2 weeks following Jolie’s NYT disclosure, 4,500 additional BRCA tests were carried out, which cost the US healthcare system some US$13.5m. Interestingly, increased testing rates were not accompanied by a corresponding increase in mastectomy rates, which suggests that additional testing did not identify new BRCA mutations. Thus, the Angela Jolie effect might have encouraged over-testing among low-risk women.
 
Mindful of her influence on women’s decisions, in 2015 Jolie wrote another NYT article in which she attempted to correct her earlier support for radical risk reduction surgery for women carriers of BRCA mutations. She said that because surgery worked for her, it is not necessarily the optimal therapeutic pathway for all women, and stressed that non-surgical treatments could be more appropriate.
 
Traditional genetic testing for breast cancer risk was slow and expensive

Genetic testing to detect BRCA mutations has been available since 1996, but for many years it was under-used because of its scarcity, high cost, and the length of time it took to produce a result. The rapid development and plummeting costs of genetic testing, and a 2013 US Supreme Court ruling, which invalidated the patents held by Myriad Genetics Inc., which restricted BRCA testing, have resulted in the growth and accessibility of genetic testing.
 
BRCA testing is not straightforward

There are hundreds of mutations in the BRCA1 and BRCA2 genes that can cause cancer. Several different tests are available, including tests that look for a known mutation in one of the genes (i.e., a mutation that has already been identified in another family member), and tests that check for all possible mutations in both genes. Commercial laboratories usually charge between US$450 and US$5,000 to carry out BRCA testing, depending on whether you are being tested for only a specific area(s) of a gene known to be abnormal or if hundreds of areas are being examined within multiple genes. Tests that use traditional technology take several months to report findings. This means that even if a woman is tested at the time of diagnosis, she might not know the results before she has to decide on treatment.
 
Importance of regulated testing laboratories

Testing for the BRCA genes usually involves a blood sample taken in a doctor’s clinic and sent to a commercial laboratory. In 1988, the US Congress passed the Clinical Laboratory Improvement Amendments (CLIA) to ensure quality standards, and the accuracy and reliability of results across all testing laboratories. Since then, all legitimate genetic testing in the US is undertaken in CLIA-approved facilities. During testing for BRCA mutations, the genes are separated from the rest of the DNA, and then scanned for abnormalities. Unlike other clinical screening such as HIV tests and colonoscopies, which provide a simple positive or negative result; genetic testing is fraught with uncertainty because it reveals the likelihood of developing cancer rather than a certain fate.
 
BRCA1 and BRCA2 genetic test results
 
A positive BRCA test result indicates that you have inherited a known harmful mutation in the BRCA1 or BRCA2 gene. This means that you have an increased risk of developing breast and ovarian cancers, but it does not mean that you will actually develop cancer. Some women who inherit a harmful BRCA mutation will never develop cancer. A positive test result may create anxiety and compel clinicians to perform further tests and women to undergo premature and unnecessary clinical interventions, other women in a similar situation will opt for regular screening.
 
The potential benefits of a true negative result include a sense of relief regarding your future risk of cancer, learning that your children are not at risk of inheriting the family's cancer susceptibility, and that a range of interventions may not be required. However, a negative result sometimes can be difficult to interpret because its meaning partly depends on your family’s history of cancer, and whether a BRCA mutation has been identified in a blood relative. Further, scientists continue to discover new BRCA1 and BRCA2 mutations, and have not yet identified all potentially harmful ones. Therefore, it is possible that although you have a “negative” test result you might have a harmful BRCA1 or BRCA2 mutation, which has not been identified.
 
Counselling
 
Because of these uncertainties and the agonising choices women with suspected breast cancer face, health providers in most developed countries recommend counselling as part of breast cancer treatment pathways. In the video below Dr John Green, a medical oncologist knowledgeable about the influence of inherited BRCA gene mutations on treatment options underlines the importance of expert genetic counselling to help women navigate their therapeutic pathways. Counselling is performed by a health professional experienced in cancer genetics, and usually includes the psychological risks and benefits of genetic tests, a hereditary cancer risk assessment based on a person’s personal and family medical history; a description of the tests, their technical accuracy and appropriateness, medical implications of a positive or a negative test result, the possibility of uncertain or ambiguous test results, cancer risk-reducing treatment options, and the risk of passing on a mutation to children. Because people are more aware of the genetic mutations linked to breast cancer, the demand for genetic testing and counselling have increased, and in some instances it is challenging for genetic counsellors to keep pace with demand.
 
 
The context in which genetic tests are carried out

A 2017 study published in the Journal of Clinical Oncology suggests that genetic test results for breast cancer are not being clearly communicated to women, and this could cause them to opt for treatments that are more aggressive than they actually need. To reduce this possibility the Royal Marsden NHS Trust Hospital in London has introduced the Mainstreaming Cancer Genetics programme. Since 2014 the Marsden has employed genetic counseling and used laboratories with enhanced genetic testing capabilities. This reduces processing time and costs, helps to meet the increased demand for rapid, accurate and affordable BRCA testing, and helps women make critical decisions about their treatment options.
 
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,” says Nazneen Rahman, Professor and Head of Cancer Genetics at the UK’s Institute for Cancer Research in London. “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,” says Rahman.

The Marsden is now offering tests to three times more 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.”

 
Takeaways

The history of cancer is punctuated with overzealous interventions, many of which have had to be modified once it has been demonstrated that they could cause more harm than good.

As advanced genetic testing becomes affordable and more accessible it is important that their results are interpreted with the help of genetic counsellors in a broader familial context in order to help women make painfully difficult decisions about their treatment.
 
Migration to next generation genetic testing technologies has many benefits, but it also introduces challenges, which arise from, the choice of platform and software, and the need for enhanced bio-informatics analysts, which are in scarce supply. An efficient, cost-effective accurate mutation detection strategy and a standardized, systematic approach to the reporting of BRCA test results are central for diagnostic laboratories wishing to provide a service during a time of increasing demand and downward pressure on costs.
 
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Anthony Pais

Senior Consultant Surgical Oncology

Dr. Anthony Vijay Pais, Breast Surgeon, Professor & Senior Consultant in Surgical Oncology is the Head of the Breast Unit and Women's oncology at the Mazumdar Shaw Cancer Center and the Narayana Hrudayalaya Multi Speciality Hospital, Bangalore, India.

Being in the field of surgical oncology for 23 years he felt the need to develop a separate speciality for breast cancer and associated diseases. He also had special training to start a 'Breast Centre of Excellence' at the John Hopkins Avon Breast Centre, Baltimore, USA.

He has conducted several cancer detection camps for the underprivileged people and Bruhat Bangalore Mahanagara Palike workers, throughout Karnataka.

 Under his guidance and direction, maximum number of breast cancer resections with immediate micro vascular reconstructions have been conducted in India (state of the art surgery done in the US), for the poorest of the poor.

He has published over 14 papers, and has 16 presentations to his credit. He has delivered 44 lectures at various hospitals and health centres.

Dr.Pais has gone through special training in Breast Ultrasound and Interpreting Mammograms in Japan and the USA. He has also got a certificate of competence to assess mammograms from the world renowned Radiologist Prof. Laszlo Tabar, Prof of Radiology, University of Uppsala School of Medicine, Sweden


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