© 2014 S. Karger GmbH, Freiburg.Background: The aim of this retrospective study was to evaluate the prognostic factors in patients operated for stage IIIC breast carcinoma who had > 10 positive axillary lymph nodes (pN3a). Patients and Methods: The medical records of 302 operated N3a breast cancer patients without distant metastasis followed up in 2 medical oncology clinics in Ankara between January 1998 and June 2013 were evaluated retrospectively. Results: The median age was 50 (21-83) years. The median follow-up time was 43 (5-191) months. The patients were divided into 4 subgroups according to hormone receptor (HR) and human epidermal growth factor receptor 2 (HER2) status. There were 151 (50.0%) patients in the HR+/HER2- group, 80 (26.5%) patients in the HR+/HER2+ group, 42 (13.9%) patients in the HR-/HER2+ group, and 29 (9.6%) patients in the triple negative (TN) group. At the time of analysis, 155 (51.3%) patients had recurrent disease and 117 (38.7%) patients had died. The median disease-free survival (DFS) and overall survival (OS) times were 46.0 and 78.0 months, respectively. Both the DFS and OS in the HR+/HER2- group were longer than in the other groups (log-rank p = 0.034 and p = 0.016, respectively). Menopausal status, progesterone receptor (PgR) status, and lymph node ratio (LNR; defined as the number of positive lymph nodes compared to the total number of removed lymph nodes) were found to be independent prognostic factors (p = 0.019, p = 0.001, and p = 0.012, respectively). Conclusion: Menopausal status, PgR status, and LNR were independent prognostic factors in operated N3a breast cancer patients, who are underrepresented in breast cancer trials.