Bilateral breast cancer

The bilateral nature of breast cancer is generally accepted. Early detection of second primary breast cancers through repeated physical and x‐ray examinations is difficult and uncertain. A significant number of occult second primary breast cancers have been detected in their earliest stages through generous surgical biopsy of the opposite breast at the time of initial mastectomy for a proven breast cancer. Some of these early cancers were not detected by either careful physical examination or adequate x‐ray mammography. Biopsy of the contralateral breast is a minor nondeforming operation which is well‐accepted by the patient. The second mastectomy is more readily accepted by the patient after a positive biopsy has been obtained. Simultaneous, generous excisional biopsy of the opposite breast at the time of initial mastectomy for breast cancer represents a practical approach to the problem of bilateral breast cancer. However, a negative biopsy of the opposite breast does not rule out the possibility of subsequent development of a new primary in this breast at a later date. All patients undergoing mastectomy for breast cancer should be followed closely, with particular emphasis on the opposite breast. There is an urgent need for the development of more efficient methods for detecting early breast cancer, preferably, during its long, silent noninfiltrating phase of development.