Objective. To study disorders associated with the risk of progression and deterioration in quality of life in patients with multiple myeloma (MM) and monoclonal unspecified gammopathy (MGUS).

Materials and methods. The study included 127 MM patients and 182 MGUS patients. All patients underwent general clinical, laboratory and instrumental studies.

Results. MGUS and MM progression over the follow-up period was detected in 10.9 % cases. The presence of destructive lesions was more frequently detected in MGUS patients with subsequent progression to MM (p<0.002). Among MM patients the excess of b-CrossLaps level occurred in 2.06 times more often than in MGUS patients. At the stage of MGUS  in 25.3 % of patients (according to the level of osteocalcin) and in 16.1 % (according to the level of VAR) had disorders in the processes of bone tissue formation. In MGUS patients with high levels of osteocalcin and no destructive changes an improvement in progression-free survival was found (p=0.046). In patients with MM and kidney damage and/or the presence of light chains of immunoglobulins the increased galectin-3 was determined in 10.74 times more frequently than in other patients (p=0.002). In MGUS patients with a b2-microglobulin level >3 mg/l an increased level of galectin-3 was detected 4.82 times more often than in other patients (p=0.02).

Chronical pain syndrome in MM patients did not depend on gender and age. It contributed to a decrease in motion activity, required individual titration of pain therapy.

Conclusion. It was found that the serum-bone turnover marker b-CrossLaps is important for predicting the disease progression.

Galectin-3 can serve as a marker of tumor progression in MM and MGUS patients with kidney damage.

Chronical pain syndrome in MM patients did not depend on gender and age. It contributed to a decrease in motion activity, required individual titration of pain therapy.

The use of ENMG method improves the diagnostic accuracy of neurological examination.