Irish Cancer Society Report Shows Patients May Wait Two Years or More for Genetic Cancer Test Results

Wait times blamed on the Irish National Health System’s ‘overstretched’ services and ‘under-resourced’ commitment to cancer genetic testing done by medical laboratories

Histopathologists in the UK and anatomic pathologists in the US understand the important role predictive genetic testing can play in helping patients understand their risk for certain types of breast, bowel, and ovarian cancers. While timely access to cancer testing may be routine in the United States, a report out of Ireland reveals patients in that country’s government-run healthcare system may have to wait up to two years or more for genetic counseling and testing.

The report, titled, “The Unmet Need in Cancer Genetic Services:

Conducting an Environmental Scan of the Cancer Genetics Services in an Irish Context Underpinned by a Mixed Methods Approach,” was prepared for the Irish Cancer Society (ICS) by researchers at the University of College Cork (UCC). The researchers found that genetic services have been “starved of investment and resources,” leaving healthcare workers involved in cancer genetics and follow-on services “doing incredible work,” but “completely overstretched.”

UK Patients in Need of Genetic Services Are Switching from Public to Private Healthcare

While early access to genetic testing can provide opportunities for preventative treatments or earlier diagnosis of cancer, many patients in Ireland with a family history of cancer must wait months or years for genetic services. UCC Nursing Professor and Physiologist Josephine Hegarty, PhD, lead author of the ICS report, stated in a news release that “public cancer genetic services are overstretched. Waiting lists exist at every point on the pathway for people who need genetic services.”

She added, “Many patients spoken to seemed to abandon the waiting for overstretched public services in favor of paying for private testing and treatment.” 

While the ICS report’s survey sample size was small—154 patients, family members, or members of the public—the data revealed:

  • One in seven respondents waited 13-24 months and one in 27 waited over 24 months for counseling and testing appointments.
  • Many people had changed from the public health system to private healthcare to speed up access to genetic testing.
  • The cumulative waiting time from referral to counseling, testing, receipt of genetic test results, and onwards to screening, surveillance, or prophylactic treatments [aka, preventive healthcare] can be up to four years, which patients see as time lost in terms of cancer prevention and early intervention.

Barriers to Genetic Services Affect Treatment Decisions

A separate survey of 52 healthcare professionals highlighted barriers for accessing services with six in 10 respondents saying they are under-resourced and four in 10 concerned about access to follow-up surgery for patients deemed to be at high risk.

In the ICS news release, breast cancer patient Margaret Cuddigan said genetic testing was not available to her at diagnosis.

“In those 13 months waiting for a result, I went through chemotherapy, a lumpectomy, and radiotherapy on my breast, only for a double mastectomy to be required once the BRCA mutation was known. Had I known this earlier, my course of treatment could have been very different,” Cuddigan said.

“I had to postpone a radiation treatment to go up to Dublin from Cork to do the genetic test, as it would have taken up to another 12 months in Cork, and then I waited over four months for the results. Once I received the news of the gene mutation, I had to navigate a path of risk-reducing surgeries,” she noted, adding, “I researched and sought out a surgeon myself.”

Long Waits for Genetic Testing Are Common in Single-Payer Healthcare

The waiting list for genetic cancer testing has long been an issue in Ireland. A 2017 article in the Irish Examiner, titled, “Woman Faces 18-month Wait for Vital Cancer Test,” brought to light the 18-month waiting time for BRCA1 and BRCA2 mutation testing for breast cancer. While the COVID-19 pandemic has further exacerbated the backlog of cancer treatment services, such issues are not new in single-payer healthcare systems.

Across the Irish Sea in Great Britain, some patients have experienced delays of six months before getting cancer test results. In “Shortage of Histopathologists in the United Kingdom Now Contributing to Record-Long Cancer-Treatment Waiting Times in England,” Dark Daily reported how prolonged wait times for cancer test results in the United Kingdom’s National Health Service are one disadvantage of a government-run, single-payer health system. With limited funds, frequently the government health program under invests in certain clinical services. It is not until several years later that the underinvestment reveals itself in the form of lengthy wait times.

Meanwhile, it is cancer patients and their families who pay the price for underinvestment because delays in their cancer test results then delay timely treatment decisions. This is particularly true when an immediate start of therapy for an aggressive form of cancer is imperative.

ICS Executive Director, Advocacy and External Relations, Rachel Morrogh, argues the solution is prioritizing cancer prevention within the Health Service Executive, which runs Ireland’s national healthcare system.

“The reality is the focus must be on urgent care, but we’re missing chances to keep people healthy (through genetic testing),” Morrogh told the Irish Independent. “We can prevent four in 10 cancers, but we have to prioritize prevention. There needs to be a significant investment and the expansion of capacity across all the follow-on services that someone with a genetic risk of cancer may need, focusing on the development of a dedicated and resourced pathway for them.

Irish Cancer Society’s Director of Advocacy and External Affairs Rachel Morrogh (above left with Donal Buggy, Director of Services, Delivery and Innovation at ICS) maintains that “Patients [in the Irish healthcare system] need a dedicated group of multi-disciplinary doctors following them so that they can be offered options and psycho-oncology support when they need it.” She added, “The government must now listen to patients and those working in our hospitals and provide more resourcing and staffing.” (Photo copyright: Irish Examiner.)

The ICS report found that limited access to timely genetically-guided health and oncology services is the result of multiple barriers to care.

“It is apparent from engaging directly with service users that waiting lists exist at every point on the pathway for people who need genetic [cancer testing] services,” the report states. “For those who may have a genetic risk of cancer, the wait times for access to [genetic cancer] testing alone (before counselling treatment, prophylactic surgery, etc.) can be up to two years. Barriers to accessing cancer genetic services include costs of tests, long processing time for referrals to tests, restrictive referral criteria, and difficulty in accessing information on cancer genetic services.”

In the forward she wrote for the ICS report, ICS Chief Executive Officer Averil Power said her organization would continue its push for improved access to genetic testing services. “Government needs to not only expand capacity for testing and counselling, but also ensure that the follow-on services that are needed by people diagnosed with a genetic risk of cancer are in place and can be accessed swiftly.”

The ICS report is another reminder to histopathologists in the UK—as well as anatomic pathologists in the US—that a single-payer healthcare system comes with its own flaws and access-to-care issues.

Andrea Downing Peck

Related Information:

Some People Waiting Over a Year for Cancer Risk Tests: Report

The Unmet Need in Cancer Genetics Services: Conducting an Environmental Scan of the Cancer Genetics Services in an Irish Context Underpinned by a Mixed Methods Approach

People with Family History of Cancer Waiting Two Years for Genetic Testing, Study Finds

Woman Faces 18-Month Wait for Vital Cancer Test

Irish Cancer Society: €30m Needed for ‘Stretched’ Services

Shortage of Histopathologists in the United Kingdom Now Contributing to Record-Long Cancer-Treatment Waiting Times in England

Common DNA Testing Method Using SNP Chips Struggles to Find Rare Variants Associated with BRCA Test, UK Researchers Find

Results of the UK study confirm for clinical laboratory professionals the importance of fully understanding the design and function of SNP chips they may be using in their labs

Here is another example of a long-established clinical laboratory test that—upon new evidence—turns out to be not as accurate as once thought. According to research conducted at the University of Exeter in Devon, UK, Single-nucleotide polymorphism (SNP) chips (aka, SNP microarrays)—technology commonly used in commercial genetic testing—is inadequate at detecting rare gene variants that can increase breast cancer risk.  

A news release announcing the results of the large-scale study states, “A technology that is widely used by commercial genetic testing companies is ‘extremely unreliable’ in detecting very rare variants, meaning results suggesting individuals carry rare disease-causing genetic variants are usually wrong.”

Why is this a significant finding for clinical laboratories? Because medical laboratories performing genetic tests that use SNP chips should be aware that rare genetic variants—which are clinically relevant to a patient’s case—may not be detected and/or reported by the tests they are running.

UK Researchers Find ‘Shockingly High False Positives’

The objective of the Exeter study published in British Medical Journal (BMJ), titled, “Use of SNP Chips to Detect Rare Pathogenic Variants: Retrospective, Population Based Diagnostic Evaluation,” was “To determine whether the sensitivity and specificity of SNP chips are adequate for detecting rare pathogenic variants in a clinically unselected population.”

The conclusion reached by the Exeter researchers, the BMJ study states, is that “SNP chips are extremely unreliable for genotyping very rare pathogenic variants and should not be used to guide health decisions without validation.”  

Leigh Jackson, PhD, Lecturer in Genomic Medicine at University of Exeter and co-author of the BMJ study, said in the news release, “The number of false positives on rare genetic variants produced by SNP chips was shockingly high. To be clear: a very rare, disease-causing variant detected using [an] SNP chip is more likely to be wrong than right.” 

Caroline Wright, PhD, Professor in Genomic Medicine at the University of Exeter Medical School
In the news release, Caroline Wright, PhD (above), Professor in Genomic Medicine at the University of Exeter Medical School and senior author of the BMJ study, said, “SNP chips are fantastic at detecting common genetic variants, yet we have to recognize that tests that perform well in one scenario are not necessarily applicable to others.” She added, “We’ve confirmed that SNP chips are extremely poor at detecting very rare disease-causing genetic variants, often giving false positive results that can have profound clinical impact. These false results had been used to schedule invasive medical procedures that were both unnecessary and unwarranted.” (Photo copyright: University of Exeter.)

Large-Scale Study Taps UK Biobank Data

The Exeter researchers were concerned about cases of unnecessary invasive medical procedures being scheduled by women after learning of rare genetic variations in BRCA1 (breast cancer type 1) and BRCA2 (breast cancer 2) tests.

“The inherent technical limitation of SNP chips for correctly detecting rare genetic variants is further exacerbated when the variants themselves are linked to very rare diseases. As with any diagnostic test, the positive predictive value for low prevalence conditions will necessarily be low in most individuals. For pathogenic BRCA variants in the UK Biobank, the SNP chips had an extremely low positive predictive value (1-17%) when compared with sequencing. Were these results to be fed back to individuals, the clinical implications would be profound. Women with a positive BRCA result face a lifetime of additional screening and potentially prophylactic surgery that is unwarranted in the case of a false positive result,” they wrote.

Using UK Biobank data from 49,908 participants (55% were female), the researchers compared next-generation sequencing (NGS) to SNP chip genotyping. They found that SNP chips—which test genetic variation at hundreds-of-thousands of specific locations across the genome—performed well when compared to NGS for common variants, such as those related to type 2 diabetes and ancestry assessment, the study noted.

“Because SNP chips are such a widely used and high-performing assay for common genetic variants, we were also surprised that the differing performance of SNP chips for detecting rare variants was not well appreciated in the wider research or medical communities. Luckily, we had recently received both SNP chip and genome-wide DNA sequencing data on 50,000 individuals through the UK Biobank—a population cohort of adult volunteers from across the UK. This large dataset allowed us to systematically investigate the performance of SNP chips across millions of genetic variants with a wide range of frequencies, down to those present in fewer than 1 in 50,000 individuals,” wrote Wright and Associate Professor of Bioinformatics and Human Genetics at Exeter, Michael Weedon, PhD, in a BMJ blog post.

The Exeter researchers also analyzed data from a small group of people in the Personal Genome Project who had both SNP genotyping and sequencing information available. They focused their analysis on rare pathogenic variants in BRCA1 and BRCA2 genes.

The researchers found:

  • The rarer the variant, the less reliable the test result. For example, for “very rare variants” in less than one in 100,000 people, 84% found by SNP chips were false positives.
  • Low positive predictive values of about 16% for very rare variants in the UK Biobank.
  • Nearly all (20 of 21) customers of commercial genetic testing had at least one false positive rare disease-causing variant incorrectly genotyped.
  • SNP chips detect common genetic variants “extremely well.”

Advantages and Capabilities of SNP Chips

Compared to next-gen genetic sequencing, SNP chips are less costly. The chips use “grids of hundreds of thousands of beads that react to specific gene variants by glowing in different colors,” New Scientist explained.

Common variants of BRCA1 and BRCA2 can be found using SNP chips with 99% accuracy, New Scientist reported based on study data.

However, when the task is to find thousands of rare variants in BRCA1 and BRCA2 genes, SNP chips do not fare so well.

“It is just not the right technology for the job when it comes to rare variants. They’re excellent for the common variants that are present in lots of people. But the rarer the variant is, the less likely they are to be able to correctly detect it,” Wright told CNN.

SNP chips can’t detect all variants because they struggle to cluster needed data, the Exeter researchers explained.

“SNP chips perform poorly for genotyping rare genetic variants owing to their reliance on data clustering. Clustering data from multiple individuals with similar genotypes works very well when variants are common,” the researchers wrote. “Clustering becomes more difficult as the number of people with a particular genotype decreases.”

Clinical laboratories Using SNP Chips

The researchers at Exeter unveiled important information that pathologists and medical laboratory professionals will want to understand and monitor. Cancer patients with rare genetic variants may not be diagnosed accurately because SNP chips were not designed to identify specific genetic variants. Those patients may need additional testing to validate diagnoses and prevent harm.

—Donna Marie Pocius

Related Information:

Large-scale Study Finds Genetic Testing Technology Falsely Detects Very Rare Variants

Use of SNP Chips to Detect Rare Pathogenic Variants: Retrospective, Population-Based Diagnostic Evaluation

The Home DNA Kits “Falsely Warning of High Risk of Cancer”: DIY Genetic Tests are “Extremely Unreliable” at Detecting Rare Genetic Variants, Major New Study Warns

SNP Chips Perform Poorly for Detecting Rare Genetic Variants

Chip-based DNA Testing Wrong More than Right for Very Rare Variants

Common Genetic Tests Often Wrong When Identifying Rare Disease-Causing Variants Such as BRCA1and BRCA2, Study Says

AdventHealth Gives 10,000 Floridians Free Genetic Tests, Sees Genomics as the Future of Precision Medicine

Many other healthcare systems also are partnering with private genetic testing companies to pursue research that drive precision medicine goals

It is certainly unusual when a major health network announces that it will give away free genetic tests to 10,000 of its patients as a way to lay the foundation to expand clinical services involving precision medicine. However, pathologists and clinical laboratory managers should consider this free genetic testing program to be the latest marketplace sign that acceptance of genetic medicine continues to move ahead.

Notably, it is community hospitals that are launching this new program linked to clinical laboratory research that uses genetic tests for specific, treatable conditions. The purpose of such genetic research is to identify patients who would benefit from test results that identify the best therapies for their specific conditions, a core goal of precision medicine.

The health system is AdventHealth of Orlando, Fla., which teamed up with Helix, a personal genomics company in San Mateo, Calif., to offer free DNA sequencing to 10,000 Floridians through its new AdventHealth Genomics and Personalized Health Program. A company news release states this is the “first large-scale DNA study in Florida,” and that it “aims to unlock the secret to a healthier life.”

The “WholeMe” genomic population health study screens people for familial hypercholesterolemia  (FH), a genetic disorder that can lead to high cholesterol and heart attacks in young adults if not identified and treated, according to the news release.

Clinical laboratory leaders will be interested in this initiative, as well other partnerships between healthcare systems and private genetic testing companies aimed at identifying and enrolling patients in research studies for disease treatment protocols and therapies. 

The Future of Precision Medicine

Modern Healthcare reported that data from the WholeMe DNA study, which was funded through donations to the AdventHealth Foundation, also will be used by the healthcare network for research beyond FH, as AdventHealth develops its genomics services. The project’s cost is estimated to reach $2 million.

“Genomics is the future of medicine, and the field is rapidly evolving. As we began our internal discussions about genomics and how to best incorporate it at AdventHealth, we knew research would play a strong role,” Wes Walker MD, Director, Genomics and Personalized Health, and Associate CMIO at AdventHealth, told Becker’s Hospital Review.

“We decided to focus on familial hypercholesterolemia screening initially because it’s a condition that is associated with life-threatening cardiovascular events,” he continued. “FH is treatable once identified and finding those who have the condition can lead to identifying other family members who are subsequently identified who never knew they had the disease.”

The AdventHealth Orlando website states that participants in the WholeMe study receive information stored in a confidential data repository that meets HIPAA security standards. The data covers ancestry and 22 other genetic traits, such as:

  • Asparagus Odor Detection
  • Bitter Taste
  • Caffeine Metabolism
  • Cilantro Taste Aversion
  • Circadian Rhythm
  • Coffee Consumption
  • Delayed Sleep
  • Earwax Type
  • Endurance vs Power
  • Exercise Impact on Weight
  • Eye Color
  • Freckling
  • Hair Curl and Texture
  • Hand Grip Strength
  • Height
  • Lactose Tolerance
  • Sleep Duration
  • Sleep Movement
  • Sleeplessness
  • Sweet Tooth
  • Tan vs. Sunburn
  • Waist Size

Those who test positive for a disease-causing FH variant will be referred by AdventHealth for medical laboratory blood testing, genetic counseling, and a cardiologist visit, reported the Ormond Beach Observer.

One in 250 people have FH, and 90% of them are undiagnosed, according to the FH Foundation, which also noted that children have a 50% chance of inheriting FH from parents with the condition.

AdventHealth plans to expand the free testing beyond central Florida to its 46 other hospitals located in nine states, Modern Healthcare noted.

Other Genetics Data Company/Healthcare Provider Partnerships

In Nevada, Helix partnered with the Renown Health Institute for Health Innovation (IHI) and the Desert Research Institute (DRI) to sequence 30,000 people for FH as part of the state’s Healthy Nevada Project (HNP).

Helix (above) is one of the world’s largest CLIA-certified, CAP-accredited next-generation sequencing labs. The partnership with AdventHealth offered study participants Exome+: a panel-grade medical exome enhanced by more than 300,000 informative non-coding regions; a co-branded ancestry + traits DNA product for all participants; secure storage of genomic data for the lifetime of the participant; infrastructure and data to facilitate research; and in-house clinical and scientific expertise, according to Helix’s website. (Photo copyright: Orlando Sentinel.)

Business Insider noted that Helix has focused on clinical partnerships for about a year and seems to be filling a niche in the genetic testing market.

“Helix is able to sidestep the costs of direct-to-consumer marketing and clinical test development, while still expanding its customer base through predefined hospital networks. And the company is in a prime position to capitalize on providers’ interest in population health management,” Business Insider reported.

Another genomics company, Color of Burlingame, Calif., also has population genomics programs with healthcare networks, including NorthShore University Health System in Ill.; Ochsner Health System in La.; and Jefferson Health in Philadelphia.

Ochsner’s program is the first “fully digital population health program” aimed at including clinical genomics data in primary care in an effort to affect patients’ health, FierceHealthcare reported.

In a statement, Ochsner noted that its innovationOchsner (iO) program screens selected patients for:

  • Hereditary breast and ovarian cancer due to mutations in BRCA1 and BRCA2 genes;
  • Lynch syndrome, associated with colorectal and other cancers; and
  • FH.

Color also offers genetic testing and whole genome sequencing services to NorthShore’s DNA10K program, which plans to test 10,000 patients for risk for hereditary cancers and heart diseases, according to news release.

And, Jefferson Health offered Color’s genetic testing to the healthcare system’s 33,000 employees, 10,000 of which signed up to learn their health risks as well as ancestry, a Color blog post states.

Conversely, Dark Daily recently reported on two Boston healthcare systems that started their own preventative gene sequencing clinics. The programs are operated by Brigham and Women’s Hospital and Massachusetts General Hospital (MGH).

And a Precision Medicine Institute e-briefing reported on Geisinger Health and Sanford Health’s move to offer genetic tests and precision medicine services in primary care clinics.

“Understanding the genome warning signals of every patient will be an essential part of wellness planning and health management,” said Geisinger Chief Executive Officer David Feinberg, MD, when he announced the new initiative at the HLTH (Health) Conference in Las Vegas. “Geisinger patients will be able to work with their family physician to modify their lifestyle and minimize risks that may be revealed,” he explained. “This forecasting will allow us to provide truly anticipatory healthcare instead of the responsive sick care that has long been the industry default across the nation.”

It will be interesting to see how and if genetic tests—free or otherwise—will advance precision medicine goals and population health treatments. It’s important for medical laboratory leaders to be involved in health network agreements with genetic testing companies. And clinical laboratories should be informed whenever private companies share their test results data with patients and primary care providers. 

—Donna Marie Pocius

Related Information:

It May Be Your DNA: First Large-Scale DNA Study in Florida Aims to Unlock the Secret to a Healthier Life

AdventHealth Offers Free DNA Tests to 10,000 Floridians

How AdventHealth Orlando is Building a Future in Genomics

Helix Partners with AdventHealth to Offer 10,000 Genetic Screenings in Florida

AdventHealth to Launch Large Genetic Study for High Cholesterol

Ochsner Health System Teaming Up with Genetic Testing Company Color in Population Genomics

The Healthy Nevada Project: from Recruitment to Real-World Impact

Ochsner Health System to Pilot Genetic Screening Program in Partnership with Color

North Shore and Color Unlock the Power of Genomics in Routine Care

Jefferson Heath and Color Advancing Precision Health Through Clinical Genomics and Richer Data

Two Boston Health Systems Enter the Growing Direct-to-Consumer Gene Sequencing Market by Opening Preventative Genomics Clinics, But Can Patients Afford the Service

Geisinger Health and Sanford Health Ready to Offer Genetic Tests and Precision Medicine Services in Primary Care Clinics

Precision Medicine Requires Targeted Cancer Therapies, but Payers Reluctant to Pay for Some Genetic Testing Needed to Match a Patient with Right Drug

Precision Medicine Requires Targeted Cancer Therapies, but Payers Reluctant to Pay for Some Genetic Testing Needed to Match a Patient with Right Drug

Clinical labs and pathology groups know how advances in targeted therapies and genomics far outpace providers’ and patients’ ability to know how best to use and pay for them.

One fascinating development on the road to precision medicine is that many new cancer drugs now in clinical trials will require a companion genetic test to identify patients with tumors that will respond to a specific therapeutic drug.

This implies more genetic testing of tumors, a prospect that challenges both the Medicare program and private health insurers because they already struggle to cope with the flood of new genetic tests and molecular diagnostic assays. However, even as this genetic testing wave swamps payers, some pharmaceutical companies have cancer drugs for rare types of cancers and these companies would like to see more genetic testing of tumors.

Pathologists and clinical laboratory managers will find this to be precisely the dilemma facing specialty pharma company Loxo Oncology (NASDAQ:LOXO), a biopharmaceutical company located in San Francisco and Stamford, Conn.

Loxo is developing larotrectinib (LOXO-101), a “selective TRK inhibitor.” According to a Loxo press release, Larotrectinib is “a potent, oral, and selective investigational new drug in clinical development for the treatment of patients with cancers that harbor abnormalities involving the tropomyosin receptor kinases (TRK receptors).” In short, the drug is designed to “directly target TRK, and nothing else, turning off the signaling pathway that allows TRK fusion cancers to grow.”

How to Find Patients for This Cancer Drug

While a powerful, new, targeted cancer drug will be a boon to cancer therapy, it is only intended for a relatively small number of patients. Loxo estimates that between 1,500 and 5,000 cases of cancer are caused by TRK mutations in the United States each year. Conversely, according to the National Cancer Institute, the total number of new cancer diagnoses in the US in 2016 was 1,685,210.

An article in MIT Technology Review on larotrectinib notes, “To find patients, Loxo will need to convince more doctors to order comprehensive tests that screen multiple genes at once, including TRK.” And that is where things get complicated.

“These advanced genetic tests, which can cost $5,000 or more, are offered by companies like Foundation Medicine, Caris Life Sciences, and Cancer Genetics. The problem is, insurers still consider the tests ‘experimental’ and don’t routinely cover them, meaning patients are often stuck picking up the bill,” notes MIT Technology Review.

Data for the graph above comes from the National Human Genome Research Institute. The graph illustrates the steep decline in cost for whole genome sequencing over the past 17 years. As the cost of genetic testing drops, development of targeted-drug cancer therapies increases. Clinical laboratories and anatomic pathology groups can expect to be performing more such tests in the future. (Graphic copyright: National Human Genome Research Institute/Simple English Wiki.)

To further confuse the market, the National Cancer Institute states that “Insurance coverage of tumor DNA sequencing depends on your insurance provider and the type of cancer you have. Insurance providers typically cover a DNA sequencing test if there is sufficient evidence to support that the test is necessary to guide patient treatment. Tests without sufficient evidence to support their utility may be considered experimental and are likely not covered by insurance.”

Many reliable sources agree. For example, the US National Library of Medicine Genetics Home Reference states, “In many cases, health insurance plans will cover the costs of genetic testing when it is recommended by a person’s doctor.”

That, however, leads to a different conundrum for drug makers such as Loxo: the majority of doctors are not keeping up with the rapid-fire pace of discovery in the realm of genetics and targeted therapies. Some genes like BRCA1 and BRCA2 are familiar enough to doctors that they know how and why they are important. However, most other genes are less known, and critically, less understood by doctors who must also focus on all the other myriad aspects of patient care.

In an article on the Color Genomics $249 Hereditary Cancer Test, which tests for mutations in 30 genes, Timothy Hamill, MD, Professor Emeritus, University of California San Francisco (UCSF) Department of Laboratory Medicine, and former overall director of UCSF’s clinical laboratories, told Wired, “If you talk to docs, they say ‘BRCA, that’s the only thing I’m interested in because I don’t know what to do with the other information.’ Doctors don’t know what to do with it. Patients don’t know what to do with it.”

More Testing Equals More Knowledge

Further complicating the issue, there is an enormous lack of information on how multipanel screenings will affect individuals, public health, and the cost of healthcare in general. Several studies are underway, but they are so new it could be years before any real results become available.

Five years ago, it cost about $20,000 to sequence the whole human genome. Now the average price is $1,500, though there are more and less expensive types of genetic tests. As the cost continues to decline, however, more people will undergo the testing and scientists will learn more about how to identify the best therapy to treat cancers caused by genetic mutations.

—Dava Stewart

Related Information:

Loxo Oncology Announces Positive Top-Line Results from Independent Review Committee Assessment of Larotrectinib Dataset

National Cancer Institute Statistics

Promising New Cancer Drugs Won’t Go Far Unless Everyone Gets Genetic Testing

Tumor DNA Sequencing in Cancer Treatment

Will Health Insurance Cover the Costs of Genetic Testing?

A Single $249 Test Analyzes 30 Cancer Genes. But Do You Need It?

Personal Genome Test Will Sell at New Low Price of $250


Genetic Fingerprint Helps Researchers Identify Aggressive Prostate Cancer from Non-Aggressive Types and Determine if Treatment Will Be Effective

New discoveries about the genetics of prostate cancer could lead to better tools for diagnosing the disease and selecting effective therapies based on each patient’s specific physiology

In recent decades, the biggest challenge for urologists, and for the pathologists who diagnosed the prostate tissue specimens they referred, has been how to accurately differentiate between non-aggressive prostate cancer, which can exist for decades with no apparent symptoms, and aggressive prostate cancer that kills quickly.

Thus, a research study that has identified unique genetic features within prostate cancer that can help determine if the cancer is aggressive or not, and whether certain drugs may be effective, is good news for men, for urologists, and for the clinical laboratories that will be called upon to perform testing.

These types of breakthroughs bring precision medicine ever closer to having viable tools for effective diagnosis of different types of cancer.

Genetic Fingerprints of Cancer Tumor Types

One such study into the genetic pathways of prostate cancer is bringing precision medicine ever-closer to the anatomic pathology laboratory. Researchers from the Princess Margaret Cancer Centre, which is associated with the University of Toronto Faculty of Medicine, have discovered that some tumors in prostate cancer have a genetic fingerprint that may indicate whether or not the disease will become more aggressive and less responsive to treatment.

Robert Bristow, MD, PhD, and Paul Boutros, PhD, conducted a study of nearly 500 Canadian men who had prostate cancer. Published in the journal Nature, the researchers examined the genetic sequences of those tumors, looking for differences between those that responded to surgery or radiation and those that did not.

Dr. Robert Bristow Video

In the video above, Dr. Robert Bristow, clinician-scientist at Princess Margaret Cancer Centre, discusses the findings of a key piece in the genetic puzzle that explains why men born with a BRCA2 mutation develop aggressive prostate cancer. (Caption and photo copyright: University Health Network/Princess Margaret Cancer Centre.)

According to a FierceBiotech article, approximately 30% of men who have a type of prostate cancer thought to be curable eventually develop an aggressive metastatic type of the disease. About half of the men who developed a metastatic form of cancer had mutations to three specific genes:

“This information gives us new precision about the treatment response of men with prostate cancer and important clues about how to better treat one set of men versus the other to improve cure rates overall,” stated Bristow in a University Health Network (UHN) press release.

In another study, researchers looked at 15 patients with BRCA2-inheritied prostate cancer and compared the genomic sequences of those tumors to a large group of sequences from tumors in less-aggressive cancer cases. According to a ScienceDaily news release, they found that only 2% of men with prostate cancer have the BRCA2-inherited type.

Knowing what type of cancer a man has could be critically important for clinicians tasked with prescribing the most efficient therapies.

“The pathways that we discovered to be abnormal in the localized BRCA2-associated cancers are usually only found in general population cancers when they become resistant to hormone therapy and spread through the body,” noted Bristow in the ScienceDaily release. If clinicians knew from diagnosis that the cancer is likely to become aggressive, they could choose a more appropriate therapy from the beginning of treatment.

Genetic Mutations Also Could Lead to Breast and Brain Cancer Treatments

BRCA mutations have also been implicated in breast, ovarian, and pancreatic cancers, among some other types. The knowledge that BRCA1 and BRACA2 mutations could indicate a more aggressive cancer is likely to spark investigation into whether poly ADP ribose polymerase (PARP) inhibitors could be used as an effective therapy.

PARP inhibitors are increasingly of interest to scientists. In addition to being used to treat some BRCA1/BRCA2-implicated cancers, two recent studies show that it could be effective in treating brain cancer with low-grade gliomas that involve a mutation to the gene isocitrate dehydrogenase (IDH), according to an article published by the National Cancer Institute and the National Institutes of Health (NIH).

Researchers of the study published in the journal Clinical Cancer Research investigated how PARP inhibitors impact DNA repair in gliomas.

Researchers of the study published in the journal Science Translational Medicine stated that they “demonstrate mutant IDH1-dependent PARP inhibitor sensitivity in a range of clinically relevant models, including primary patient-derived glioma cells in culture and genetically matched tumor xenografts in vivo.”

According to the UHN press release, the next step in using the knowledge that BRCA1 and BRCA2 may indicate a more aggressive prostate cancer is for researchers to create a diagnostic tool that can be used to determine what type of prostate cancer a man has. They expect the process to take several years. “This work really gives us a map to what is going on inside a prostate cancer cell, and will become the scaffold on which precision therapy will be built,” Boutros stated in a Prostate Cancer Canada news release.

Unlocking Knowledge That Leads to Accurate Diagnoses and Treatments

Research that furthers precision medicine and allows clinicians to choose the most appropriate treatment for individuals shows how quickly scientists are applying new discoveries. Every new understanding of metabolic pathways that leads to a new diagnostic tool gives clinicians and the patients they treat more information about the best therapies to select.

For the anatomic pathology profession, this shows how ongoing research into the genetic makeup of prostate cancer is unlocking knowledge about the genetic and metabolic pathways involved in this type of cancer. Not only does this help in diagnosis, but it can guide the selection of appropriate therapies.

On the wider picture, the research at the Princess Margaret Cancer Centre is one more example of how scientists are rapidly applying new knowledge about molecular and genetic processes in the human body to identify new ways to more accurately diagnose disease and select therapies.

—Dava Stewart


Related Information:

Genomic Hallmarks of Localized, Non-Indolent Prostate Cancer

Newly Discovered Genetic Fingerprint for Prostate Cancer Promises to Personalize Treatment

Prostate Cancer Team Cracks Genetic Code to Show Why Inherited Disease Can Turn Lethal

PARP Inhibitors May Be Effective in Brain, Other Caners with IDH Mutations

Chemosensitivity of IDH1-Mutated Gliomas Due to an Impairment in PARP1-Mediated DNA Repair

2-Hydroxyglutarate Produced by Neomorphic IDH Mutations Suppresses Homologous Recombination and Induces PARP Inhibitor Sensitivity

Prostate Cancer Researchers Find Genetic Fingerprint Identifying How, When Disease Spreads

Scientists Identify DNA Signature Linked to Prostate Cancer Severity