Breast carcinoma associated with necrotic granulomas in axillary lymph nodes

From a series of 100 consecutive breast carcinomas with axillary lymph node metastases, two cases of necrotic granulomas in the nodes are presented. Lymph nodes in each case were characterized by areas of necrosis surrounded by a palisade of cells resembling histiocytes as seen in a rheumatoid nodule. Although the initial impression was that of a reactive granuloma, when immunostained for keratin and EMA, the areas of necrosis showed positive staining for keratin and EMA in a cytoplasmic pattern. The surrounding palisade of cells stained with histiocyte markers, while the necrotic area itself was negative. Staining for both estrogen and progesterone markers was also negative. Staining of nine lymph nodes with caseating granulomas not associated with carcinoma with the same panel of antibodies revealed no staining except for irregular, noncellular staining with EMA. This pattern of necrosis in axillary lymph nodes from two cases of breast carcinoma was interpreted as evidence of necrotic metastatic tumor cells. Necrosis in axillary lymph nodes associated with invasive breast cancer should arouse suspicion for metastasis.