[Effect of different regimens on bone disease of multiple myeloma]

To explore the difference of effects of two regimens (bortezomib and dexamethasone, BD; and thalidomide and dexamethasone, TD) on bone disease in multiple myeloma (MM).

Forty patients with newly diagnosed and refractory or relapsed MM were treated with BD or TD regimens from Dec 2006 to Sep 2008. Bone pain score and X-ray examination were carried out before and after therapy. Serum levels of DKK-1, sRANKL, OPG and TRACP-5b were measured by ELISA before and 3 months after therapy.

Serum TRACP-5b concentration was significantly decreased in patients received TD regimen (5.94 U/L before therapy vs 4.84 U/L 3 months after therapy, P < 0.05), and so did for serum DKK-1 concentration in patients responded to BD regimen (35.11 µg/L before vs 32.03 µg/L 3 months after therapy, P < 0.05); for serum concentration of sRANKL in patients responded to BD regimen (1.05 pmol/L before vs 0.67 pmol/L 3 months after therapy, P < 0.05); and for serum concentration of TRACP-5b in responders to BD regimen (5.57 U/L before therapy vs 4.90 U/L 3 months after therapy, P < 0.05).

Bortezomib lowers levels of serum DKK-1 and RANKL in responders, thus leads to normalization of abnormal bone remodeling through the increase of bone formation and reduction of bone resorption. Thalidomide decreases bone resorption regardless of treatment response.