Cancer | Genetic Testing
Universal hereditary cancer genetic testing: Expanding possibilities for cancer care
A recent study suggests current genetic testing guidelines may miss patients with solid tumor cancer
Cancer has long been the subject of intense medical research and advancements. We’ve seen incredible progress in understanding and treating cancer, including the benefits of genetic testing to inform preventive treatments.
But a recent study in the Journal of Clinical Oncology Precision Oncology (JCO-PO) titled “Universal Germline Genetic Testing for Hereditary Cancer Syndromes in Patients with Solid Tumor Cancer” noted that genetic testing guidelines miss a number of patients with gene variants that are known to cause cancer.¹
This article explores the study’s key findings and highlights the potential benefits of universal hereditary cancer genetic testing (called “germline genetic testing” in the industry). Additionally, it discusses testing’s implications for patients with solid tumor cancer and how genetic testing can impact their care.
What is universal hereditary cancer genetic testing, and why is it needed?
Universal hereditary cancer genetic testing is a comprehensive screening method used to analyze an individual’s DNA for specific genetic changes that may increase their susceptibility to hereditary cancer syndromes. Traditional genetic testing targets specific genes associated with a particular type of cancer, while universal hereditary genetic testing examines a wider range.
Inherited gene variants significantly increase an individual’s risk of developing cancer over their lifetime. Early identification of these DNA changes can help guide personalized treatment decisions and preventive measures to manage a patient’s cancer risk.
In solid tumor cancers, such as breast, ovarian, colorectal, and pancreatic cancers, universal hereditary genetic testing shows immense potential in uncovering hidden hereditary cancer syndromes. Their identification allows for targeted surveillance and preventive measures for patients and their at-risk family members.
“It’s becoming clear that the personal and family history criteria we use to determine which of our cancer patients qualify for germline genetic testing fail to identify many individuals with hereditary cancer syndromes. Offering testing to all cancer patients allows us to provide the best care to individuals and their families.” — Heather Hampel, MS, CGC, Professor in the Department of Medical Oncology and Therapeutics Research and Associate Director of the Division of Cancer Genomics at City of Hope National Cancer Center
Identifying missed opportunities
Traditional cancer testing guidelines have effectively identified individuals with the highest risk of having a hereditary cancer syndrome and serve as valuable tools. However, a substantial number of patients with cancer who should have access to clinically actionable findings are missed by existing guidelines.¹
Historically, guidelines recommended hereditary genetic testing for patients with solid tumor cancers who meet specific criteria. These typically include:
- young age at cancer diagnosis
- strong family history of cancer
- multiple primary cancers
- specific tumor characteristics that suggest a potential genetic basis
Relying solely on guidelines might overlook patients with disease-causing gene variants, leaving them unaware of their genetic predisposition to cancer.¹ These gene changes, known as pathogenic variants (PGVs), are crucial in hereditary cancer syndromes and can significantly impact treatment and prevention strategies.
The power of genetic testing
In the study, a multi-gene panel was used to do genetic testing on all patients with cancer, regardless of the existing guidelines. Findings revealed that additional individuals with hereditary cancer could be identified if a universal approach is implemented.¹
Additionally, the study revealed that patients with high-penetrance variants, meaning those associated with a likely chance of developing a specific genetic condition, experienced changes in recommendations for their cancer care.
By identifying PGVs, healthcare providers gain valuable insights into an individual’s cancer risks and tailor care plans accordingly. For example, knowledge of hereditary cancer syndromes may prompt increased surveillance, risk-reducing surgeries, or targeted therapies.
Genetic testing can also provide crucial information for patients and their families, allowing them to make informed decisions about their health, including lifestyle modifications.
Testing, therefore, enables patients and their providers to take proactive steps to help reduce risks, improve health outcomes, and enhance patient well-being.
“Universal germline genetic testing can provide patients optimal access to precision therapies and clinical trials and improve access to genetic information for historically underrepresented populations, helping to overcome the persistent disparities related to equitable healthcare for patients with cancer.” — Ed Esplin, MD, PhD, FACMG, CGAF, FACP, Clinical Geneticist at Invitae
The importance of cascade family variant testing
While genetic testing for patients is essential, extending testing to their blood relatives is equally crucial. Cascade family variant testing involves testing family members to identify elevated risks of developing cancer due to shared genetic factors.
Knowledge of PGVs can support the use of targeted therapies, and the discovery of index cases in a family may prompt genetic counseling and cascade testing for at-risk family members.¹
Unfortunately, the study noted low uptake of cascade family variant testing, despite offering it at no cost. Healthcare providers can encourage wider adoption of cascade testing to ensure comprehensive risk assessment for individuals and their families and inform appropriate preventive measures.
Evolving guidelines and where to go from here
The publication of this study has already influenced changes in genetic testing guidelines. Medical organizations increasingly recognize the importance of identifying PGVs early and working on updating their recommendations to include broader testing.
By incorporating the study’s findings, these revised guidelines aim to capture a broader range of patients who may benefit from genetic testing. This proactive response reflects a commitment to improving patient care through evidence-based practices and staying at the forefront of medical advancements.
Testing all patients with solid tumors using multi-gene cancer testing panels for hereditary cancers can improve patient care and treatment options.1 Understanding the genetic basis of cancer has the potential to enhance our ability to diagnose and treat this devastating disease.
Invitae’s groundbreaking research helped show the impact of universal genetic testing for many cancer types.² By partnering with healthcare providers, Invitae enables patients to unlock valuable genetic information that can guide personalized cancer care decisions.
Learn more about hereditary cancer testing at Invitae.
References
- Esplin ED, et al. Universal Germline Genetic Testing for Hereditary Cancer Syndromes in Patients With Solid Tumor Cancer. JCO Precis Oncol. 2022;6:e2100516.
- Samadder NJ, et al. Comparison of Universal Genetic Testing vs Guideline-Directed Targeted Testing for Patients With Hereditary Cancer Syndrome [published correction appears in JAMA Oncol. 2021 Feb 1;7(2):312]. JAMA Oncol. 2021;7(2):230–237.
