Background. Many pathologic features of breast carcinomas have been proposed as prognostic correlates: their interrelationships and their relative value as prognostic indicators were studied.
Methods. A series of 399 axillary lymph node-positive infiltrating ductal breast carcinomas was studied histologically and compared with the patient prognosis.
Results. Many pathologic findings fit into two groups of closely related features-those related to the extent of local spread and those related to histologic anaplasia and mitotic count. Both groups correlated with the primary tumor size. The best predictors of long-term survival were measures of the extent of axillary metastasis (the number of axillary metastases, the size of the largest metastasis, and lymph node capsular invasion), which are components of the pathologic node stage. The mitotic count, tumor grade, primary tumor stage, smooth tumor border, tumor necrosis, and multifocal primary tumors were weaker but significant survival correlates. The mitotic count and Bloom-Richardson grade best predicted the survival time of patients with node-positive disease who died. Four years after diagnosis, less than 25% of the patients who would die of breast carcinoma in the low mitotic count and Bloom-Richardson Grade 1 (well differentiated) groups already had died; more than 75% of those in the high mitotic count and Bloom-Richardson Grade 3 (poorly differentiated) groups already had died. Among patients with small tumors (< 1.8 cm in diameter), those with one micrometastasis (1-2 mm) had a worse prognosis than those with uninvolved lymph nodes of similar size.