Genetic testing is recommended for cancer. Doing genetic testing can predict the risk of recurrence after surgery, and doing genetic testing can also help with cancer treatment. 1. Predicting the risk of post-surgical recurrence: genetic testing for early-stage cancer patients can help determine the risk of post-surgical recurrence of early-stage cancer. 2. Helping cancer treatment: genetic testing for early-stage cancer can predict the risk of recurrence after surgery; if there is no risk of recurrence, no treatment is usually done after surgery; if the risk of recurrence is high, treatment is needed after surgery to prevent recurrence. Doing genetic testing for advanced cancer can determine whether targeted drug therapy can be applied. Or immunotherapy. Cancer patients should do genetic testing or other treatments according to the need under the guidance of physician’s interview, and patients should not use drugs on their own to avoid adverse results.