Prognostic value of the interpectoral lymph nodes in breast cancer: A 20-year survival study

Introduction The indication and extent of axillary lymph node dissection in breast cancer remains open to controversy. Materials and method In this context, a 20-year survival study has been made of 1600 breast cancer patients subjected during surgical treatment to systematic dissection of the accomiothoracic vascular pedicle together with the accompanying lymph nodes (Rotter and Grossman interpectoral lymph node groups). An anatomical study of these nodes was also conducted in 100 necropsies, with the evaluation of 200 acromiothoracic vascular pedicles. Results The interpectoral lymph nodes were anatomically present in 42% of the necropsies and in 35.1% of the patients subjected to surgery. The prognosis was much worse in cases of neoplastic infiltration of the interpectoral lymph nodes (Kaplan-Meier survival study), regardless of the influence of other prognostic factors. Conclusions In view of the results obtained, the designation of grade N3 of the TNM classification is proposed for malignancies with positive interpectoral lymph node infiltration.