Decreased Muscle Mass Prior to and Following Chemotherapy Predicts Morbidity in Testicular Cancer Patients Undergoing Post-Chemotherapy Retroperitoneal Lymph Node Dissection

Introduction/Background: The importance of nutritional status before oncologic surgery has been demonstrated in several solid malignancies. Testicular cancer primarily effects young men, and therefore clinicians may not consider sarcopenia as a factor in this population. We therefore sought to determine the impact of decreased muscle mass, measured by psoas muscle diameter, on outcomes in patients undergoing post-chemotherapy retroperitoneal lymphadenectomy (PC-RPLND) for metastatic germ cell tumors (mGCTs). Materials and Methods: Records of all patients undergoing PC-RPLND for mGCTs at our institution were reviewed. Muscle mass was assessed by measuring cross-sectional area of the psoas muscle on pre-chemotherapy and pre-operative computerized tomography. Psoas Index (PSI) was calculated by adjusting total psoas area for patient height (cm²/m²). Univariate and multivariate analysis was performed to assess the predictive value of sarcopenia for morbidity and mortality following PC-RPLND. Results: From 2014-2019, 95 patients underwent PC-RPLND, of whom 64 patients had both pre-chemo and pre-operative cross-sectional imaging. Prior to chemotherapy, mean PSI was 7.36 cm²/m², which decreased to 7.06 cm²/m² (P = .041) following chemotherapy. Patients with Stage III disease had a lower mean PSI than patients with Stage I disease (6.84 cm²/m² vs 7.46 cm²/m², P = .047). Patients who suffered post-operative complications had a lower mean PSI (6.39 cm²/m² vs 7.37 cm²/m², P = .020). Conclusion: Decreased muscle mass was predictive of morbidity in patients undergoing PC-RPLND. Patients with higher disease burden had lower pre-operative muscle mass. Further assessment of pre-operative nutritional status in this population may reduce morbidity following PC-RPLND.