The Impact of Sarcopenia On Transplant-Related Outcomes in Patients with Non-Hodgkin's and Hodgkin's Lymphoma

Sarcopenia is a state of abnormally low muscle mass that is associated with more treatment-related complications, shorter time to recurrence or progression, and shorter overall survival in patients with different cancers, including lymphoma, pancreatic, lung, and breast cancer. Sarcopenia is a potentially modifiable host factor that can be easily and reliably obtained from routine computerized tomography (CT). The objective of this study is to determine whether sarcopenia impacts transplant-related outcomes in patients undergoing autologous and allogeneic hematopoietic stem cell transplantation (HSCT) for Hodgkin's lymphoma (HL) or non-Hodgkin's lymphoma (NHL). Patients transplanted between 6/2005 and 6/2012 at the University of Michigan BMT Program were eligible for inclusion if a CT of the abdomen was performed within 60 days prior to HSCT. Cross-sectional area and density of the psoas muscles at the level of the fourth lumbar vertebra were calculated. Lean psoas muscle mass accounting for fatty infiltration was determined using algorithms programmed in the Analytic Morphomics Lab at the University of Michigan. Results: Total psoas area and lean psoas area were calculated for 121 autologous transplant patients who met inclusion criteria. The median total psoas area/height was 1255.2 mm²/m and the median lean psoas area/height was 977.4 mm²/m. After controlling for age and gender, the hazard ratio for non-relapse mortality (NRM) was 0.79 (C.I. 0.60, 1.05), p = 0.088 for every 100 mm²/m increase in total psoas area/height and 0.75 (C.I. 0.55, 1.04), p = 0.099 for every 100 mm²/m increase in lean psoas area/height. Patients were then divided into tertiles for total psoas area/height and lean psoas area/height. Since only one NRM event was observed among included women and occurred in a woman in the lowest tertile for total psoas area/height and lean psoas area/height, the tertile anlaysis was conducted in only men. Among all included men, a greater NRM was seen in the patients in the bottom two tertiles, compared to the tertile with the greatest muscle mass and can be observed in the attached figure ( p=0.02 and p=0.03 for a log-rank test of the lowest and middle tertile respectively). In the 43 allogeneic transplants, sarcopenia had no impact on outcome. Conclusion: Patients with a greater degree of pre-transplant sarcopenia who underwent an autologous HSCT for NHL or HL  had a greater risk of NRM than those with greater muscle mass. CT-determined psoas muscle mass may be a valuable addition to comorbidity indices used to guide optimal treatment selection and serve as a potentially modifiable host factor  to improve transplant-related outcomes. This difference was not noted in the allogeneic transplant population, where a different and more complex set of complications may come into play, although this requires confirmation in a larger sample.