Retroperitoneal fibrosis: A rare manifestation of extramedullary dissemination of multiple myeloma

Multiple myeloma is a neoplasm that occurs due to monoclonal proliferation of plasma cells. Anemia, hypercalcemia, renal failure, and osteolytic lesions are the common manifestations. Less than 5% of patients present with extramedullary dissemination at the time of diagnosis. The common sites of extramedullary dissemination are liver, spleen, adrenals, and lung. Spread of myeloma into retroperitoneum causing retroperitoneal fibrosis is one of the rare manifestations. Patients with disseminated myeloma are usually young and have a poor disease-free survival rate. Aggressive therapy in the form of stem cell transplant has shown to be of benefit in such patients.