Necessity for Increased Screening for Genetic Testing Eligibility Among Long-Term Breast Cancer Survivors

Germline genetic testing is an important tool for identifying hereditary gene mutations known to increase the risk of developing cancers. Approximately 8% of patients with breast cancer will have a clinically actionable germline mutation, but the frequency of genetic testing is lower than would be expected in both the acute and extended phases of breast cancer survivorship care. Breast cancer survivorship care includes the continuing evaluation of patient cancer history and offering appropriate genetic counseling and testing to those patients who meet specific eligibility guidelines.

Breast cancer survivors receiving care from a single nurse practitioner–led long-term cancer survivorship clinic between May 2019 and January 2021 were evaluated to determine the relationship between germline testing and the frequency of germline variants within this cohort of 2184 patients. Screening was performed to determine if initial germline testing was needed, if testing had already been completed, or if testing required updating if previously done. Of the total number of patients screened, 401 were eligible for initial or updated germline testing and were offered genetic education, counseling, and multigene panel testing (7 declined). Seventy-five percent of participants who underwent genetic testing had a positive family history, were average age of 60.2 years, and average age at diagnosis of 50.1 years. Genetic testing revealed 11.3% had pathogenic variants an average of 10.7 years since initial breast cancer diagnosis.

The data emphasize the importance of frequent screening among breast cancer survivors for genetic testing eligibility as 11% of breast cancer survivors in the present study were shown to carry pathogenic genetic mutations a decade after initial diagnosis. Even in a clinic where genetic testing is customary, a number of patients were eligible for but had not completed genetic evaluation. Point-of-care genetic testing for patients with breast cancer can identify the risk of developing secondary cancers and appropriate therapeutic options.

Source: Ranallo L, Nye LE, Williams M, et al. Point of care genetic testing in a breast cancer survivorship clinic. American Society of Clinical Oncology Virtual Meeting; June 4-8, 2021. Abstract 10580.