Cutaneous Extramedullary Plasmacytoma

Abstract

Extramedullary plasmacytoma (EMP) of the skin is a rare indolent neoplasm that shares morphological and immunophenotypic features with plasma cell myeloma (PCM), but the molecular features that distinguish these two entities have not been defined. We reviewed the clinical characteristics, course, and molecular abnormalities in 7 cases of cutaneous EMP (cEMP); 2 patients had primary cEMP and 5 had secondary cEMP. Two patients died of progressive extramedullary plasmacytoma, 1 without PCM; 1 patient who had only a hyperdiploid clone, died within 17 months of the diagnosis of cEMP; and 3 died of PCM. One patient, who had cEMP with a hyperdiploid clone and a 13q deletion, was alive 28 months after diagnosis. Our findings raise questions about the relative prognostic value of molecular aberrations observed in cEMP and PCM. The role of fluorescence in situ hybridization testing in predicting disease progression of cEMP remains to be defined.

Therapy for Relapsed Multiple Myeloma

“…118,175–179 Often patients with plasma cell leukemia have rapidly dividing cells with a high plasma cell labeling index or “S” fraction, and although they respond to therapy, the duration of response is usually short. 180 Progression to secondary plasma cell leukemia or development of extramedullary myeloma may occur at any time in the course of the disease and is often associated with the acquisition of novel chromosomal abnormalities such as 17p deletion, 181,182 MYC upregulation, 181,183 and loss of 1p.…”

Subcutaneous Nodules on the Head and Ankle: Answer

“…2,3 Lesions appear as erythematous to violaceous papules, nodules, or plaques that vary in ulceration and tenderness on the trunk, head, and extremities. 1,3…”

“…2 Although EMPs commonly arise in the upper aerodigestive tract, they can also arise in the skin, causing cutaneous extramedullary plasmacytomas (cEMPs). 1,2 Cutaneous involvement in the setting of multiple myeloma is rare. 2,3 Lesions appear as erythematous to violaceous papules, nodules, or plaques that vary in ulceration and tenderness on the trunk, head, and extremities.…”

“…3 Patients with underlying multiple myeloma tend to experience frequent relapses and progression of cEMPs. 1 Therapy for plasmacytomas includes multiagent chemotherapy, radiation therapy, or stem cell transplantation. 1,4 Unfortunately, there is a poor prognosis after the appearance of cutaneous lesions, with a survival rate of approximately 1 year.…”

“…1 Therapy for plasmacytomas includes multiagent chemotherapy, radiation therapy, or stem cell transplantation. 1,4 Unfortunately, there is a poor prognosis after the appearance of cutaneous lesions, with a survival rate of approximately 1 year. 3,4 This case of cEMP in the setting of multiple myeloma is an example of a rare diagnosis that stresses the importance of early detection to guide proper treatment.…”