Factors influencing prognosis in node-negative breast carcinoma: analysis of 767 T1N0M0/T2N0M0 patients with long-term follow-up.

PURPOSE: This study was undertaken to define prognostically favorable and unfavorable subgroups of node-negative breast carcinoma patients by employing conventional pathologic data. PATIENTS AND METHODS: Seven hundred sixty-seven women with T1N0M0/T2N0M0 breast carcinoma treated consecutively from 1964 through 1970 by modified or radical mastectomy without systemic adjuvant therapy were analyzed at a median follow-up duration of 18 years. RESULTS: Size and histologic type of the carcinoma were crucial discriminants of prognosis. We defined a prognostically favorable group of 219 patients (29%) with infiltrating duct or lobular carcinoma < or = 1.0 cm in diameter or special tumor types < or = 3.0 cm. This group had a relapse-free survival rate of 91% at 10 years and 87% at 20 years. The less favorable group (548 patients, 71%) with infiltrating duct or lobular carcinoma greater than 1.0 cm and special tumor types greater than 3.0 cm had relapse-free survival rates of 73% and 68% at 10 and 20 years, respectively. The frequency of nonmammary malignant neoplasms (NMMN) was similar to that of contralateral carcinoma. Deaths due to NMMN were seven times more frequent than deaths due to contralateral carcinoma. CONCLUSION: Nearly 30% of these node-negative patients, identified on the basis of tumor size and type, had an extremely favorable prognosis. There is insufficient evidence to warrant the routine use of adjuvant therapy in this group unless new forms of treatment prove to be less toxic and/or more effective in enhancing relapse-free survival. Early detection of NMMN should be an important part of the follow-up of node-negative breast carcinoma patients.