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.