Genetic testing has several important implications in the management of cancer
Genetic testing is generally done for patients with a significant family history of cancer, or some specific patterns of presentation of cancer. If a causative germline mutation is identified, the individual’s family members are also screened for it.
Thus, a cancer patient who gets suitable genetic testing done also helps save lives of family members by making them aware of any causative mutation present in their genes.
https://www.firstpost.com/health/genetic-testing-for-cancer-why-it-makes-sense-11582751.html
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