It's been over three decades since genetic testing was first introduced as a tool for patients at risk of hereditary cancer syndromes. In its early days, genetic testing was expensive and time-consuming (often taking up to eight weeks for results). Fast forward to today and genetic testing is now a routine part of cancer care. It’s more accessible, comprehensive and, perhaps most importantly, significantly impactful for patients and their families.
Physicians help identify patients who could benefit from genetic testing, especially when someone has a personal or family history of cancer. Genetic testing can improve treatment outcomes, guide preventive care and provide vital information for the patient's family.
Benefits of genetic testing
1. Understanding the cause of cancer
One of the most common questions from patients newly diagnosed with cancer is, "Why did this happen to me?" While many cancers are the result of environmental factors, aging and sporadic mutations, genetic testing can offer a more definitive answer. For patients with hereditary cancer, knowing their cancer is genetically driven can help ease feelings of uncertainty and guilt.
For many, this knowledge brings a sense of empowerment, as they now have the opportunity to make informed decisions regarding their treatment and potential preventive measures for the future. This hereditary cancer risk was present since birth, and there was very little if anything the patient could have done differently throughout their life to prevent their diagnosis.
2. Personalized treatment options
For patients with cancers like breast, ovarian, pancreatic and prostate, identifying genetic mutations (like BRCA mutations) can open the door to personalized therapies. The earlier in the diagnostic process the genetic test is ordered, the quicker the patient can be matched with appropriate treatments.
Knowledge of genetic mutations can also guide surgical decisions. Patients with BRCA-positive breast cancer may be candidates for risk-reducing mastectomy or salpingo-oophorectomy—both of which can lower the risk of future cancers. These decisions are most effective when genetic results are available before surgery.
3. Identification of additional cancer risks
Cancer does not always occur in isolation, especially in patients with hereditary cancer syndromes. For instance, patients with Lynch syndrome, a leading cause of colorectal cancer, are also at increased risk for uterine cancer—up to 60%. If identified before a colon resection, this knowledge could allow a hysterectomy at the same time if necessary, minimizing the risk of a second cancer and optimizing care.
Beyond immediate cancer treatment, genetic testing can also lead to additional screenings that might otherwise be missed. For example, the ATM gene is a known contributor to prostate and breast cancer. But patients with an ATM gene mutation are also at elevated risk for pancreatic cancer. While general population screening is not typically recommended, high-risk patients should begin annual imaging and/or endoscopic ultrasounds as early as age 50 or 10 years before the earliest known pancreatic cancer in their family.
4. Informed decisions for family members
A cancer diagnosis doesn’t only affect the patient—it impacts their entire family. Once a genetic mutation is identified, relatives can undergo testing to assess their own cancer risk and talk to their care teams about screenings.
Testing the affected patient first is the most informative strategy for relatives. Patients with negative genetic test results can be reassured that relatives are not at significant risk for the same diagnosis.
The role of genetic counseling in cancer care
Genetic counselors provide the expertise necessary to interpret complex genetic results, discuss the implications for patients and their families, and offer psychological support throughout the process. Genetic counseling not only helps patients make sense of their genetic test results, but also provides them with the tools to make informed decisions about their health.
Counseling also helps address the emotional and psychological aspects of genetic testing, from potential feelings of anxiety to guilt and even empowerment. Research shows that genetic counseling has a positive impact on patient knowledge, reduces anxiety and can improve overall psychological well-being during a cancer journey.
