The association of sarcoidosis with multiple myeloma is not well known. Including this case report, 12 cases of patients with both sarcoidosis and multiple myeloma have been reported in the literature. The skeletal lesions of both conditions have many clinical and radiological similarities, and unless clinicians are aware of the association and the possibility of dual pathologies, the diagnosis of multiple myeloma in patients known with sarcoidosis may be missed. We present a case of a patient known with longstanding sarcoidosis who was found to have multiple lesions on magnetic resonance imaging (MRI) involving the pelvis and both proximal femurs. Histological analysis revealed the presence of both non-necrotising granulomas consistent with sarcoidosis, and sheets of plasma cells consistent with a plasma cell neoplasm.
Keywords: Case report; Lymphoproliferative disorder; Multiple myeloma; Sarcoidosis; Skeletal.