Solitary Bone Plasmacytoma Progressing into Retroperitoneal Plasma Cell Myeloma with No Related End Organ or Tissue Impairment: A Case Report and Review of the Literature

Abstract

Solitary bone plasmacytomas and plasma cell myeloma are clonal proliferations of plasma cells. Many patients with solitary bone plasmacytomas develop plasma cell myeloma on follow-up. We present a case of a 70-year-old man who presented with fracture and a lytic lesion in the subtrochanteric region of the left femur and was assigned a diagnosis of solitary bone plasmacytoma. He received local curative radiotherapy. However, 4 months later his serum M protein and β2-microglobulin levels increased to 2.31 g/dL and 5.965 mg/L, respectively. He complained of abdominal fullness and constipation. Ultrasound and non-contrast CT imaging revealed multiple retroperitoneal masses. Colonoscopic examination was normal. Biopsy of the a retroperitoneal mass confirmed it to be a plasmacytoma. Repeat hemogram, blood urea, serum creatinine, skeletal survey, and bone marrow examination revealed no abnormalities. This is an unusual presentation of plasma cell myeloma, which manifested as multiple huge extramedullary retroperitoneal masses and arose from a solitary bone plasmacytoma, without related end organ or tissue impairment and bone marrow plasmacytosis. The patient succumbed to his disease 8 months after the appearance of the retroperitoneal masses. This case highlights the importance of close monitoring of patients diagnosed with solitary bone plasmacytoma with increased serum M protein and serum β2-microglobulin levels, so that early therapy can be instituted to prevent conversion to plasma cell myeloma.

Fibrous Dysplasia of the Clivus: Case Report and Literature Review

“…Management of plasmacytomas is by radiation therapy, and surgery is only indicated when tumor bulk leads to neurologic issues secondary to the mass effect. Other clival tumors to consider include osteomas, chondromas, ameloblastic fibromas, and giant cell granulomas [ 18 ].…”

Extramedullary plasmacytoma of maxilla with cervical nodal metastasis associated with sinonasal aspergillosis

“…PET-CT scan, skeletal survey and bone marrow biopsy should be considered at least annually or as clinically indicated. [9][10][11] The prognosis is more favorable in patients with primary EMP not associated with MM. Although a small proportion of these patients have a rapidly progressive course with dissemination and death in a few months, about 33-75% survive for five years.…”

Femoral Neck Fracture in the Setting of Plasmacytoma: A Case Report

“…Solitary plasmacytomas can be further divided into SBPs, as mentioned above, or solitary extramedullary plasmacytomas (SEPs) based on the origin of the lesion. SBPs usually occur in the axial skeleton, particularly the vertebrae, and skull; however, SEPs have also been found infrequently in the ribs, pelvis, femur, scapula, and clavicle [1][2][3].…”