Q. "What are the chances of the cancer coming back if I get a lumpectomy with radiation? If it comes back, is it likely to be invasive? If I decide on a lumpectomy/radiation, how can you be sure there are no other 'spots' in the breast? Wouldn't a mastectomy eliminate that possibility?"
A. Approximately one of every ten patients who are treated with lumpectomy and radiation therapy will have a recurrence of breast cancer in the same breast within 12 years. Recurrence in the same breast usually requires additional surgery, but does not affect chances of survival compared to mastectomy. However, fear of recurrence of breast cancer is the reason why many women prefer a mastectomy to a lumpectomy. It seems rather obvious that you can't get cancer in your breast if your breast is removed. However, women who have undergone a mastectomy can still experience a recurrence on the chest wall where the breast was removed. Recurrence on the chest wall following a mastectomy is slightly less likely than recurrence in the same breast following a lumpectomy and radiation.
Recurrence of cancer in the other breast or elsewhere in the body does not differ between mastectomy patients and lumpectomy patients.