CT-derived relationship between low relative muscle mass and bone damage in patients with multiple myeloma undergoing stem cells transplantation

Objective: Sarcopenia or low muscle mass is related to worse prognosis in cancer patients. We investigated whether muscle mass is related to bone damage on CT in patients with multiple myeloma (MM). Methods: Approval from the institutional review board was obtained. N = 74 consecutive patients (mean age, 60.8 years +/- 9.24 [standard deviation]; range, 36-89 years) for MM who underwent transplant were included. Sarcopenia cut-off points defined as skeletal muscle index (SMI) used were<41cm(2)/m(2). To assess bone damage in MM the MSBDS (myeloma spine and bone damage score) was used. One-way analysis of variance and the X-2 test were used. Kaplan-Meier analysis was performed to generate progression and survival curves according to SMI and MSBDS. The testing level was set at 0.05. Results: The median SMI was 47.1 +/- 14.2 and according to SMI 18/74 (24%) had sarcopenia which was more prevalent in females (p.001). A strong and significant association between patients with low muscle mass and elevated bone damage (24/74, 32.4%) and patients with normal/non-low muscle mass low bone damage (30/74, 40.5%) was present. Multiple Logistic regression did not show any significant relationship or confounding influence among SMI and MSBDS regarding sex (p.127), cytogenetic status (p.457), staging (p.756) and relapse (126). Neither SMI nor MSBDS resulted significantly related to overall survival as shown in Kaplan-Meier analysis. Conclusion: Sarcopenia and bone damage affected MM patients undergoing stem cell transplantation and are significantly associated. Advances in knowledge: Quantitative measurement of sarcopenia and bone damage on CT resulted present in MM patients undergoing stem cell transplantation and are significantly associated.