Immunohistochemical and clinicopathologic features of estrogen receptor-negative, progesterone receptor-positive, HER-2 negative breast carcinomas

SUMMARY OBJECTIVE: Currently, there is an ongoing debate whether progesterone receptor positive and estrogen negative breast carcinomas represent a true distinct subtype of tumor or mere immunohistochemical artifact. In this study, we conducted immunohistochemistry panel with the antibodies TFF1, EGFR, CK5 to reclassify phenotype in luminal basal-like subtype. METHODS: Tumors -/progesterone +, Her-2 – from large population cancer patients were selected be studied. Immunohistochemistry was performed. showing positivity for regardless EGFR results, classified as luminal-like carcinomas. Those lesions that but and/or CK5, triple-negative When three markers negative, tumors undetermined. Clinical pathologic characteristics recurrence evaluated. RESULTS: Out 1188 investigated, 30 cases (2.5%) presented +/HER2- phenotype. Of them, 27 (90%) carcinomas, one (3.3%), two undetermined (6.7%). The mean follow-up study group 27.7 (2.7 50) months. 26 patients, 6 had recurrence: 2 local 4 systemic recurrences. average time 17 (8 38) CONCLUSION: Estrogen +/tumors exhibit aggressive behavior, similar tumors. An appropriate categorization these should made improve their therapeutic management.