Impact of Sarcopenia and Osteopenia on Prognosis in Metastatic Biliary Tract Cancer: A Single Center Experience

Sarcopenia, defined as skeletal muscle loss, has been known as a poor prognosis factor in various malignant diseases. We aimed to investigate the effect of sarcopenia on prognosis in patients with metastatic biliary tract cancer (mBTC) who received chemotherapy. We retrospectively collected clinic data of 70 patients with mBTC. Computed tomography scans were used to determine the skeletal muscle index at the third lumbar vertebra level for sarcopenia. Osteopenia was defined by averaging the radiodensity of consecutive five lumbar vertebrae in non-contrast CT scan images. Overall survival (OS) and progression free survival (PFS) were analyzed according to sarcopenia and osteopenia. Sarcopenia was present in 39 (55.7%) patients. Osteopenia was present 36 (51.4%) patients. Median PFS was 3.4 (2.7-4.1) and 6.5 (5.1-8.0) months in the sarcopenia and non- sarcopenia groups. Median OS was 4.1 (3.3-4.8) and 13.2 (9.9-16.4) months in the sarcopenia and non- sarcopenia groups. On multivariate analysis, the presence of sarcopenia (HR: 3.22, <i>p</i> = 0.001) and male sex (HR: 1.91, <i>p</i> = 0.02) were an independent predictor of poor OS. Osteopenia was not significantly associated with PFS and OS. Sarcopenia was associated with poor survival for metastatic BTC. Our aim was to raise awareness by emphasizing modifiable factors.