Survival in bilateral breast cancer.

The presence of bilateral invasive breast cancer places the patient in a state of double jeopardy. At Memorial Sloan-Kettering Cancer Center, the overall 10-year recurrence rate for unilateral Stage I breast cancer was 16%, whereas the recurrence rate for simultaneous, bilateral Stage I breast carcinoma was 29%: almost twice as high. The average 10-year survival of all patients with negative axillary nodes was 57%. In this retrospective analysis of 403 patients with bilateral primary operable breast cancer treated at Memorial Sloan-Kettering Cancer Center, significant differences were noted in the disease-free survival between patients with bilateral noninvasive cancer, bilateral invasive cancer, and the combination of invasive and in situ cancers. Bilateral intraductal cancer and lobular carcinoma in situ offered an excellent prognosis. The combination of preinvasive cancer on one side and infiltrating carcinoma on the other had the next best survival. The in situ lesion, when treated by mastectomy, did not alter the patients' life expectancy from that of the general population with unilateral breast cancer, thus indicating that surgeons should strive to detect breast cancer in its preinvasive form. The 5- and 10-year relapse-free survival of patients with bilateral invasive disease, regardless of axillary nodal status and tumor size, was 60% and 51%, respectively, for patients with a bilateral presentation and 54% and 38%, respectively, for carcinomas presenting metachronously. More important in determining prognosis, however, was the number of axillary nodes involved and the level of involvement. Invasion of bilateral axillary nodes at all levels predicted a poor prognosis. Because of this shortened survival, systemic adjuvant therapy should be considered for patients with bilateral invasive disease. The most common preinvasive breast cancer was lobular carcinoma in situ and the most frequently invasive tumor was infiltrating duct cancer. Since a contralateral breast cancer at the time of definitive treatment of the first side does not always present as a mass or with positive mammography, a random biopsy of the second breast is recommended. This should be done in the upper, outer quadrant and should include the subareolar area. With prompt adequate treatment, it is expected that survival from bilateral breast cancer should improve.