Plasmacytoma of the breast - A report of two cases diagnosed by aspirationbiopsy

BACKGROUND: Extramedullary plasmacytoma of the breast is an uncommon neopla sm, occurring either as a solitary tumor or as evidence of disseminated mul tiple myeloma. CASE: Two cases of plasmacytoma of the breast were diagnosed by fine needle aspiration cytology. Aspiration smears showed a dispersed population of pl asmacytoid cells with eccentric nuclei, abundant cytoplasm and the characte ristic paranuclear hof. CONCLUSION: The clinical, cytologic and immunopheno typic features of plasmacytoma are characteristic, and the importance of di stinguishing these neoplasms from primary mammary tumors is important to av oid unnecessary surgery.