As far as breast cancer is concerned the spread or seeding caused by biopsy won’t cause any additional complications or impact prognosis . The best way to diagnose the disease and also to get enough sample for all necessary tests are biopsy . Without diagnosing there won’t be any treatment possible . So please convince the patient to undergo biopsy , it’s safe and best investigation . There are few others type of cancers which biopsy will have bad impact on the prognosis of the patient , breast cancer is so far not proven to be one among them so , please advise the patient to undergo the test . You can consult me if the patient is still not convinced or have any further doubts .

Diagnosis can be made only by biopsy of the tissue. If there was a history of cancer in the family, all the more reason you should get the evaluation done appropriately. Cancer does not spread just by touching or biopsy. Cancer spreads if we delay the diagnosis but not by biopsy. There is no other way to prove malignancy other than tissue diagnosis, rest all are supportive evidences to this.