REPORT OF A CASE
A 57-year-old white man was diagnosed in May 1989 with IgG-κ multiple myeloma after presenting with lytic lesions of the skull, femurs, and several thoracic vertebrae. The initial serum M protein level was 48 g/L. He was treated initially with the SWOG protocol, which includes vincristine, carmustine, adriamycin, melphalan, cyclophosphamide, and prednisone.In November 1989, a subcutaneous, freely movable submental mass developed just left of the midline (Figure 1). The mass enlarged rapidly and became painful. Representative sections of a fine-needle aspiration are shown in Figure 2.What is your diagnosis?
Cutaneous extramedullary plasmacytoma.
Numerous malignant plasma cells are seen.
The patient received x-rays (20 Gy) to the neck with excellent response. However, over the next few months, new lesions developed involving the head, trunk, left arm, and groin (Figure 3). Again, fine-needle aspiration was consistent with
Thomas GW, Vaughn RY, Dunlap DB. Subcutaneous Masses With Multiple Myeloma. Arch Dermatol. 1993;129(10):1335-1336. doi:10.1001/archderm.1993.01680310105021