Prognostic and therapeutic significance of pathological features of breast cancer.

A search for significant pathological prognostic variables for 10-year disease-free survival was performed in women enrolled in protocol 4 of the National Surgical Adjuvant Breast and Bowel Project (NSABP) who were treated by radical mastectomy. Pathological assessment of the number of lymph nodes with metastatic involvement (0, 1-3, or 4+) is the principal factor. Women with tumors measuring less than 2 cm had statistically significant better survival than those with larger cancers. This association was independent of nodal status, but the magnitude of difference was only 15%. A pattern of germinal center predominance in regional lymph nodes and high histological grade adversely influenced disease-free survival in patients without nodal metastases. A high histological grade and tumor size of 2 cm or more similarly affected disease-free survival in patients with metastases in 4 or more nodes. Although no statistically significant factors were found that might predict treatment failure or success in the patients with 1-3 positive nodes, trends relating to histological grade and tumor size were observed. The presence of more than 13 positive nodes indicated patients who would fail by 10 years, after surviving for 5 years, whereas type 1, 2, and 4 "scar" cancers were favorable indices. Favorable response to chemotherapeutic agents used in clinical trials by the NSABP was significant in patients with poorly differentiated cancer but not in those with well-differentiated cancer (grades 1 and 2). This relationship prevailed in both older (greater than or equal to 50 yr) and younger (less than or equal to 49 yr) women.(ABSTRACT TRUNCATED AT 250 WORDS)