Background/purpose: Recurrent biliary obstruction (RBO) after self-expandable metallic stent (SEMS) insertion is a big problem in patients with unresectable malignant biliary obstruction (MBO). Sarcopenia is associated with poor prognosis in patients with malignancies. The purpose of this study is to clarify the relationship between RBO and sarcopenia.
Methods: Forty-six patients with normal psoas muscle mass index (PMI) and 55 with low PMI were enrolled, based on PMI cut-off values. We analyzed the cumulative incidences and predictors of RBO, considering death without RBO to be a competing risk.
Results: In the Kaplan-Meier analysis, the 60-, 180-, and 360-day cumulative incidence rates of RBO were 0.0%, 12.2%, and 22.0% in the normal PMI group, as compared to 4.0%, 31.1%, and 55.0% in the low PMI group, respectively (log-rank P = .003). In competing risk analysis, the incidences were 2.9%, 2.9%, and 7.1% in the normal PMI group, as compared to 13.7%, 34.8%, and 51.7% in the low PMI group, respectively (P < .001). In multivariate Cox regression and Fine-Gray's analyses, hazard ratios of low PMI for RBO were 4.593 (95% confidence interval 1.673-12.61, P = .003) and 4.980 (2.045-12.13, P < .001), respectively.
Conclusions: Sarcopenia in MBO was an independent risk factor for RBO.
Keywords: competing risk; psoas muscle mass index; recurrent biliary obstruction; sarcopenia; self-expandable metallic stent.
© 2021 Japanese Society of Hepato-Biliary-Pancreatic Surgery.