The Relationship between Multiple Myeloma with Renal Failure and Metastatic Calcification.

While cases of multiple myeloma (MM) with metastatic calcification have been reported, the mechanisms for this calcification have yet to be explained. We observed a case of MM in a patient with end-stage renal failure who developed vascular and pulmonary calcification. A 51-year-old male was diagnosed with Bence-Jones type MM and required maintenance hemodialysis. He was treated with bortezomib-dexamethasone, vincristine-doxorubicin-dexamethasone, the M2 protocol, and lenalidomide-dexamethasone (Rd) therapy. During the sixth cycle of Rd therapy, he complained of pain in both lower legs. Well-demarcated ulcers with severe pain had developed on the right lower leg, both exterior thighs, and penis. We found that the patient's serum intact parathyroid hormone level was elevated, while it had previously been permissively controlled. Computed tomography scan showed widespread centrilobular opacities of the bilateral lungs and high-density lesions along small blood vessels in the trunk and all four extremities. Histological calcifications were identified in small blood vessels and the alveolar walls. The risk of metastatic calcification in MM appears to be associated with renal failure, but not with MM itself.