Cutaneous Plasmacytoma: An Uncommon Entity

Abstract

Extramedullary plasmacytoma is a manifestation of multiple myeloma in which a discrete mass of neoplastic monoclonal plasma cells forms within soft tissue [1]. Cutaneous plasmacytoma remains an uncommon entity. We present a case of a 61-year-old female with a seven-year history of multiple myeloma diagnosed in the setting of a pathological fracture secondary to multiple lytic lesions. Patient initially went into remission after receiving Bortezomib-based chemotherapy followed by autologous stem cell transplant. Following transplant, she was noted to be in CR2 with no evidence of light chain disease for 3 years. She then developed an enlarging anterior abdominal wall mass which was consistent with plasmacytoma [2]. Core biopsy of the lesion showed CD138 positive and kappa-restricted plasma cells with a high proliferation index, thereby establishing disease relapse. The lesions continued to progress in size and number and she was hospitalized for concerns of superimposed infection. Vitals on admission were within normal limits. On exam, multiple foulsmelling, fungating tumors occupying a dimeter of 5 centimeters or more were noted on the infraumbilical region of the abdominal wall (Figures 1 and 2).