Moore et al in a study of

Moore et al., in a study of 40 patients with sarcoidosis and musculoskeletal symptoms, found intramedullary bone lesions on MRI in 43% of patients (17/40) [5]. The lesions ranged in size from 1 to 4cm. Lesions of the large bones and angiotensin receptor blocker were present in 33% of patients (13/40), 9 of which were multiple and 4 solitary. Two patients (5%) were coincidentally found to have MRI findings of AVN of the hip, both of whom were on corticosteroids. Less than half of the patients had biopsies of the lesions, all of which demonstrated non-caseating granulomas consistent with sarcoidosis. The association between sarcoidosis and myeloma is poorly understood. In a review of the literature, Sen et al. identified 11 reports of patients with sarcoidosis who developed multiple myeloma [6]. The median interval from the time of diagnosis of sarcoidosis to that of multiple myeloma was 6 years which was similar to the interval of 5 years in our patient. They found that the median age at diagnosis of sarcoidosis was 56 years which was significantly older than that of the general patient population with the disease. Sarcoidosis in older age groups is associated with a chronic active clinical course. The patient in our case report was diagnosed with sarcoidosis at a more typical age of 45 years. In a review of the literature, Brincker found 145 patients with sarcoidosis who had developed a malignant neoplasm, including 66 cases of various types of lymphoproliferative disorders [7,8]. There is evidence that patients with sarcoidosis have immune system dysregulation, including activation of CD4-positive T-helper cells, increased secretion of cytokines, and decreased CD8-positive T-suppressor cells [9,10]. The defective T-cell suppression and increased cytokine secretion have been postulated to result in stimulation of B cells. Hunninghake et al. showed that patients with sarcoidosis have greater ratios of IgG and IgM secreting cells compared to normal individuals [11]. They demonstrated that B lymphocytes in normal individuals, when cultured with T lymphocytes from patients with sarcoidosis, were induced to differentiate into immunoglobulin-secreting cells. The extended half-life of B lymphocytes and plasma cells in sarcoidosis patients may also increase their risk of undergoing neoplastic transformation. In a review on skeletal sarcoidosis, Moore et al. recommended that in a patient with proven sarcoidosis, biopsy of musculoskeletal lesions detected at MRI may not be necessary [12].
Conclusion
Conflict of interest statement
Consent
Financial remuneration