Revolutionizing Ovarian Cancer Treatment through Genetics Testing
Genetic testing in patients with ovarian cancer not only can help in determining the best targeted treatment but it also can provide information about possible inherited gene mutations which can help serve as a preventative or risk reduction to affected family members.
“Genetic testing has become a cornerstone to ovarian cancer care,” said Moffitt Cancer Center gynecological oncologist Dr. Jing-Yi Chern. She is one of the authors of an abstract presented at the 2020 American Society of Clinical Oncology (ASCO) Annual Meeting that provided a descriptive analysis of genetic testing patterns with the implementation of a genetics tumor board at a National Cancer Institute comprehensive cancer center.
Chern and her colleagues formed a Genetics Tumor Board at Moffitt that is specific to gynecology. “We are hoping to find new, innovative ways of treating our patients, and genetics adds a huge component to it. We also felt that this would be a modern and data-driven way of taking care of our patients,” said Chern.
Knowledge of Genetic Mutations Plays Role in Treatment Options
The genetic testing was for somatic mutations as well as germline mutations. Somatic testing is important for the patient because the mutation is within the tumor itself but is not passed on to children. Somatic mutations, also called acquired mutations, can cause cancer or other diseases.
“We know that in patients with an ovarian cancer, if they have a genetic mutation, whether that's germline or somatic, particularly BRCA1 or BRCA2, it has a role in their treatment management after initial surgery and chemotherapy,” said Chern. Treatment with PARP inhibitors is often administered to such patients. The genetic information may help identify patients in the recurrent setting for an appropriate clinical trial. “It does not necessarily mean that the patient will go to a clinical trial, but it gives us information to determine their eligibility for some clinical trial,” she added.
Helping Prevent Ovarian Cancer in the Future
Testing of germline mutations in patients with ovarian cancer is a way to ultimately help prevent such cancers in others.
Germline mutations are inherited from a parent, are present in all a person’s cells and can be passed on to children. Information about these mutations allows for cascade testing, a systematic process to identify people at risk for a hereditary condition. The process begins with the identification of an individual with the condition or gene mutation associated with the condition, and then genetic testing is extended to that patient’s at-risk biologic relatives. “Cascade testing is important, and it means that if a patient has an inheritable gene mutation, that inheritable mutation may be passed on to another family member. So, this allows for that information to be used, and preventative or risk reduction strategies can be implemented to those family members,” said Chern.
Genetics Tumor Board Helps Identify Patients Who Benefit from Trials
Germline testing is not more complicated than somatic testing, but to be effective it must follow a specific process. The American Society of Clinical Oncology, the Society of Gynecologic Oncology and the National Society of Genetic Counselors recommend thorough counseling before such genetic testing is performed.
“Moffitt has the advantage of having genetic counselors embedded within our institution, so we can offer and obtain germline testing, and most importantly provide the counseling the patient and their family members may need.” said Chern.
Of the patients included in the genetics tumor board, 58 of 81 (71.6%) patients received both germline and somatic testing. Genetics referrals were placed for 16 of 23 (69%) of the patients who received somatic testing without subsequent germline testing. Twelve of 81 (14.8%) genetics tumor board patients were identified for clinical trials during this time period.
Chern noted the previous historical control for genetic testing rate of about 30% at the cancer center initiated a multilevel intervention. “Since implementing the Genetics Tumor Board, we are recognizing and identifying these patients earlier, and we can get them to genetic testing a little bit more efficiently because part of our tumor board includes the genetic counselors,” she said.