Increased vascularization in myeloma.

Several studies have shown that the number of intratumoral vessels can predict the aggressiveness of a solid cancer, development of metastases and patient survival. Does angiogenesis play an important role in myeloma? The aim of our study was to quantify bone marrow vascularity in various stages of proliferative plasma cell disorders (monoclonal gammopathies of undetermined significance (MGUS), stage I multiple myeloma (MM), stage III MM and Waldenström's macroglobulinemia (WM)) and to compare it with that of patients with osteoporosis. The study included 15 MGUS patients, 15 patients with stage I MM, 15 patients with symptomatic stage III MM, 7 patients with WM, 10 patients with osteoporosis, and 10 patients with reactive bone marrow (RBM), matched for sex and age. After iliac crest biopsy, the various vessels (arterioles, capillaries and sinusoids) were labeled with monoclonal antibodies CD34 and counted, and a histomorphometric study was done. The number of arterioles and arterial capillaries was significantly increased in MGUS and myeloma compared with osteoporosis. The number of arterioles and arterial capillaries increased moderately according to the stage of gravity of myeloma. The number of arterioles is negatively correlated with the trabecular bone volume and positively correlated with the eroded surfaces.