Pathologic Quiz Case: A 39-Year-Old Man With Severe Lower Back Pain

Hemorrhagic Skin Nodules and Plaques: A Diagnostic Clue to Underlying Primary Plasma Cell Leukemia

Plasma cell leukemia (PCL) is a rare lymphoproliferative disorder characterized by a malignant proliferation of plasma cells (PC) in blood and marrow. Cutaneous involvement is very rare in PCL. We present the case of a 45-year-old lady who presented with multiple hemorrhagic nodules and plaques in the skin. Her total leucocyte count was 2,00,200/cmm with 85% abnormal plasmacytoid cells in peripheral smear. Biopsy of the skin lesions revealed diffuse infiltration by plasma cells with ‘choked’ blood vessels. A diagnosis of plasma cell leukemia with cutaneous involvement was made. On the second day of admission, the patient expired probably because of intracranial bleed due to thrombocytopenia. Post-mortem bone marrow and liver biopsy also showed diffuse infiltration by plasma cells. Monoclonality of the cells was proven by demonstrating the production of only kappa light chains.

Primary plasma cell leukemia: morphologic, immunophenotypic, and cytogenetic features of 4 cases treated with chemotherapy and stem cell transplantation

Plasma cell leukemia (PCL) is a neoplastic disorder of plasma cells of which there are 2 forms, primary PCL and secondary PCL, the latter occurring in patients with a history of plasma cell myeloma. We describe 4 patients with primary PCL. In all cases, the bone marrow aspirate smears and biopsy specimens demonstrated a diffuse infiltrate of atypical plasma cells that were difficult to classify using morphologic criteria alone. Immunophenotypic studies showed that each case was positive for plasma cell-associated antigens (cytoplasmic immunoglobin, CD38, or CD138) and negative for CD20. Of 4 cases, 3 had complex karyotypes, including the t(11;14)(q13;q32) or del(11)(q13). Despite chemotherapy and the use of novel therapeutic agents and stem cell transplantation, all 4 patients had short survival.