Primary diffuse large B cell lymphoma of the breast eight years after the diagnosis of gastric MALT lymphoma: report of first case.

Primary breast lymphoma (PBL) is an uncommon type of extranodal non-Hodgkin's lymphoma (NHL), accounting for approximately 1% of all extranodal NHL. Diffuse large B cell lymphoma (DLBCL) is the most frequent histology. Both primary mucosa-associated lymphoid tissue (MALT) lymphoma of the breast and its relapse have been documented previously. We report on a 63-year-old woman with primary DLBCL of the breast which was diagnosed 8 years after gastric MALT lymphoma. Following chemotherapy, complete response was obtained. We suggest that for women presenting with a breast mass who received cytotoxic treatment for the other lymphoma, PBL should be considered in the differential diagnosis of the breast mass together with primary breast carcinoma.