Extramedullary plasmocytoma relapsing at differents sites: an unusual presentation

Extramedullary plasmacytoma (EMP) is an uncommon plasma cell neoplasm results from plasma cell proliferation and consists of monoclonal plasmacytic infiltration, without bone marrow involvement and any other systemic characteristics of multiple myeloma. EMP accounts for 3% of all plasma cell neoplasms and approximately 80% to 90% of EMP involve submucosa of the upper aerodigestive, while scrotal, dermis and retroperitoneal infiltration are very rare. There are no consensus guidelines for treatment, but EMP is highly radiosensitive, surgery may be considered for some sites, but 11 at 30% can progress in multiple myeloma. We report here an exceptional case of recurrent EMP in much localization. It's about a man 72 years old with initially testicular plasmocytoma who generalized the plasmacytic infiltration after 16 months in skin and progressively in mediastinal and retroperitoneal plasmacytoma, without any medullar and bone involvement.

[Primary pancreatic plasmacytoma]

Extramedullary plasmacytomas are uncommon malignant plasma cell tumors that present outside the bone marrow; 80% of extramedullary plasmacytomas are located in the upper respiratory tract, and gastrointestinal plasmacytomas are rare. We present the case of an asymptomatic 65-year-old man in whom a pancreatic mass was found incidentally. The lesion was determined to be a pancreatic plasmacytoma after fine-needle aspiration cytology and surgical resection. No clinical, laboratory, or imaging findings indicative of multiple myeloma or association with other plasmacytomas were found, so the tumor was considered to be a primary pancreatic plasmacytoma.

Extramedullary plasmocytoma associated with a massive deposit of amyloid in the duodenum

We report a rare case of extramedullary plasmocytoma associated with a massive deposit of amyloid in the duodenum. A 72-year-old Japanese man was admitted to our hospital presenting with a 3-mo history of epigastric pain, vomiting and weight loss. On computed tomography (CT) a wall thickening of the fourth part of the duodenum was observed. Multiple biopsies obtained from the lesion showed infiltration of plasma cells and lymphocytes, but they were not conclusive. The patient underwent resection of the lesion and, on histopathological examination, the lesion consisted of a dense and diffuse infiltrate of plasma cells and a few admixed lymphocytes with reactive follicles extending to the muscular propria. An extensive deposition of amyloid was also observed. Immunohistochemical stains revealed that a few plasmacytoid cells showed λ light chain staining, though most were κ light chain positive. These cells also were positive for CD138 and CD56 but negative for CD20 and CD79. The findings were consistent with extramedullary plasmocytoma associated with a massive deposit of amyloid in duodenum. A subsequent workup for multiple myeloma was completely negative. The patient showed no signs of local recurrence or dissemination of the disease after 12 mo follow-up. Because of the association of plasmocytoma and amyloidosis, the patient must be followed up because of the possible systemic involvement of the neoplasm and amyloidosis in future.