Purpose: The prognostic role of the site of the primary breast cancer has not been clarified. This study aimed to gather more information about this issue from a large series of patients with long-term follow-up data.
Patients and methods: Data from 2,396 patients treated for early breast cancer with a conservative approach were reviewed (1973 to 1989). In 1,619 patients, the tumor had a lateral site, while in 777 cases, it was situated in the internal/central quadrants. The characteristics of the two groups were well balanced, apart from axillary nodal metastases, which were more frequent for lateral tumors (38.1% v 26.3%).
Results: Analysis of distant metastases indicated that the regression coefficient associated with tumor site was significant and the hazards ratio estimate was 1.291, which indicates the risk of distant metastases was increased by approximately 30% for internal/central tumors. The analysis of overall survival yielded a significant coefficient and a hazards ratio of 1.192, which indicates an approximately 20% increase of mortality for internal/central tumors.
Conclusion: Early breast cancers situated in central/ internal quadrants have a worse prognosis compared with those in lateral quadrants, in terms of distant metastases and survival. Irradiation of the internal mammary chain for internal/medial tumors could be suggested, but, to date, the therapeutic strategy is still controversial.