- © 2003 by American Society of Clinical Oncology
Hematologic Malignancies With Extramedullary Spread of Disease
Case 1. Multiple Myeloma With Extramedullary Involvement of the Pleura and Testes
A 62-year old man was admitted to our hospital for fatigue. Laboratory tests revealed the presence of anemia (hemoglobin, 10.5 g/dL), with total serum protein of 12.1 g/dL and M-component IgG immunoglobulin (8,520 mg/dL). Serum immunoelectrophoresis demonstrated a spike of IgG lambda chains. Other results were a sedimentation rate of 137 mm (normal value, < 4 mm) and beta-2 microglobulin of 6.8 mg/dL (normal value, 1.2 to 2.5 mg/dL). Bence Jones lambda chains were detected in the urine. Bone marrow biopsy showed a high number of plasma cells (range, 70% to 75%) with a diffuse type of infiltration. Bone marrow (BM) aspirate showed 80% of plasma cells with hypocellular erythroid, myeloid, and megakaryocyte components. Radiographic examination demonstrated the presence of a single osteolytic lesion in distal humerus. A diagnosis of multiple myeloma (MM) was made, and the patient received five cycles of vincristine, doxorubicin, and dexamethasone (VAD) chemotherapy. After the third cycle, a partial response was observed with a reduction of BM plasmacytosis (45%). Relapse occurred after the last VAD treatment with increase in BM plasma cells to 75%. Physical examination revealed dullness and decreased breath sounds in the right lung base. Radiographic studies showed a right pleural effusion (Fig 1⇓, top). The patient developed a right hydrocele with a testicular mass. A thoracentesis and hydrocele aspiration with flow cytometry analysis showed the presence of CD138+ monoclonal plasma cells in both testicular and pleural fluid (Fig 1⇓, bottom). Cytological examination of pleural (Fig 2A⇓) and testicular fluid (Fig 2B⇓) revealed the presence of atypical immature and multinucleated plasma cells. Electrophoresis demonstrated the presence of monoclonal protein in the fluids, and polymerase chain reaction for IgH gene rearrangement showed a monoclonal band belonging to variable region of immunoglobin family (data not shown). A blood smear also showed plasma cells (about 20%). After an unexpected duodenal obstruction, ascites rapidly developed and the patient died from cardiac shock. An autopsy was not performed.
MM is a plasma cell malignancy usually restricted to the bone marrow. Extramedullary involvement (plasmacytoma) can occur occasionally, particularly in the nasopharynx, upper respiratory tract, or gastrointestinal tract.1,2 Our patient showed an unusual extramedullary spread including testis and pleural localization with a rapid and aggressive evolution. In addition, the development of duodenal obstruction with ascites that was rapidly fatal indicated a potential intestinal localization of plasmacytoma. The pleura is an unusual site for plasmacytoma.3,4 Only 0.8% of MM patients were reported to have myelomatous pleural effusion in a review from the Mayo Clinic.5 The majority are caused by IgA myeloma and, less frequently, IgG. Similarly, testicular involvement in patients with MM is a rare event, with a small number of cases reported in the literature.2,6,7 It may occur as an occasional finding during autopsy, as a primary clinical manifestation, or as a metastatic lesion in patients with multiple myeloma or plasma cell leukemia2,7
Chest radiography (top). Flow cytometry analysis of testicular and pleuric fluids (bottom).
Myeloma cells in pleuric fluid (A) and testicular fluid (B).
