Background: Although the conclusions reached in the National Surgical Adjuvant Bowel and Breast Protocol B-06 trial and other clinical trials appear to remain intact, questions persist regarding the equivalency of breast preservation compared with modified radical mastectomy for patients with invasive carcinoma. Documentation and assessment of comparative survival rates in a large cohort of nonrandomized breast carcinoma patients was undertaken to understand better these outcome patterns.
Methods: Information gathered from the medical records of 96,030 women diagnosed with early stage carcinoma of the breast between 1985 and 1988 was reviewed to determine the age at diagnosis; tumor stage, grade, dimension; treatment; and disease status.
Results: Of these 96,030 Stage I and II (based on the American Joint Committee on Cancer staging system) patients, 8583 (8.9%) were treated with segmental mastectomy, axillary lymph node dissection, and radiotherapy without systemic treatment. Three thousand seven hundred and ninety-seven patients (4.0%) were treated with segmental mastectomy, axillary lymph node dissection, radiotherapy, and systemic therapy. Forty-four thousand two hundred and forty-nine patients (46.0%) were treated with modified radical mastectomy without systemic therapy, and 18,322 patients (19.1%) were treated with modified radical mastectomy with systemic therapy. Within each stage, reported survival was equal to or more favorable for patients managed with breast preservation compared with those treated with modified radical mastectomy. This comparability was observed in all subsets analyzed including those defined by age at diagnosis, histologic grade, and tumor dimension.
Conclusions: These findings are consistent with the hypothesis that AJCC Stage I and II patients treated with breast preservation appear to have survival rates equivalent to those treated with modified radical mastectomy.