Screening for the presence of heritable mutations is, in effect, a post facto activity – predominantly used in patients who have been diagnosed with breast or ovarian cancer. NCCN guidelines indicate that women above the age of 50 years should be screened for the presence of germline (hereditary) mutations in genes that create a predisposition towards cancer. Other guidelines stipulated for recommending genetic testing increase the complexity in making use of genetic tests for identifying germline mutation carriers. In India, however, early-onset breast cancer is evident in patients as young as 30 years old. So, how should guidelines be used for genetic testing? With rigid compliance or should physicians prescribe genetic tests at their discretion, overriding age criteria? Given the high prevalence of hereditary mutations, in the Indian population, there is a high chance of missing out on identification of ‘carriers’, if testing guidelines are implemented rigorously and younger women are excluded.

In fact, even in the West, cases of genetic predisposition to hereditary breast cancer are getting missed out, if guidelines for genetic testing are adhered to rigidly (Grindedal et al. 2017). In a cohort of 1371 women newly diagnosed with breast cancer, 3.1 % of women were found to have germline (heritable) pathogenic mutations that heighten risk for breast cancer. Significantly, these investigators also identified one mutation-positive ‘carrier’ person in the family (asymptomatic) per every mutation-positive breast cancer ‘patient’. If age <40 years or incidence of TNBC were considered as indicative factors for genetic testing, only 34% carriers were identified. Adherence to international guidelines for testing resulted in the identification of ~68% (range 45-90%) of carrier individuals. Genetic testing of all women (independent of their eligibility by international guidelines) younger than 60 years resulted in identification of 90% of the carrier individuals (Grindedal et al. 2017). The data suggests that although guidelines are useful in identifying germline mutation carriers, they may not always be comprehensive. Pre-emptive determination of the genetic profile (vis-à-vis germline mutations for hereditary cancer) of all women, is the strategy that is most likely to succeed in identifying ‘carrier’ individuals. Carrier individuals can benefit from frequent medical surveillance for the earliest symptoms of breast and ovarian cancer.

Taken together, the data suggests that Indian women and their kin can benefit from pre-emptive (before the symptoms of breast cancer are evident) genetic testing to determine their personal risk for breast cancer. A predictive genetic test can empower women by establishing the need for adopting frequent surveillance measures. In turn, these steps are likely to result in detection of breast cancer in the early stages. As an initial step, perhaps, genetic testing should be advised to asymptomatic relatives of every breast and ovarian cancer patient.