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Updated: Jan 31, 2026

Endoscopic Ultrasound-Guided Biliary Drainage: Endoscopic Ultrasound-Guided Hepaticogastrostomy in Malignant Biliary Obstruction
Published on: March 25, 2022
Bone mineral density correlates with survival after resection of extrahepatic biliary malignancies
Siyuan Yao1, Toshimi Kaido1, Shinya Okumura1
1Department of Surgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan.
Background & Aims:
Osteopenia is a condition in which bone mineral density (BMD) is lower than normal, and it is an important determinant of bone fragility. However, the utility of osteopenia in assessing the risks of surgery is unclear. This study investigated the impact of preoperative low BMD on the outcomes in patients undergoing resection of extrahepatic biliary cancers.
Methods:
A retrospective analysis was performed with 181 patients who underwent resections of extrahepatic biliary cancers between 2005 and 2015. Their BMD was measured on preoperative computed tomography images. Overall survival (OS) and recurrence-free survival (RFS) rates were compared according to BMD (normal vs. low), and the prognostic factors after surgery were assessed. Propensity score matching was used to minimize the bias in patient background.
Results:
Older age and female were strongly associated with low BMD. These factors were used to construct the propensity score model, which yielded a matched cohort of 52 legs in each group. The OS (21.2% vs. 53.9% at 5 years, p < .001) and RFS (21.8% vs. 64.6% at 5 years, p < .001) rates were significantly lower in patients with low BMD (osteopenia) than in those with normal BMD (non-osteopenia). Multivariable analyses showed that low BMD was an independent factor predictive of poor OS (hazard ratio [HR]: 2.343, 95% confidence interval [CI]: 1.362-4.129, p = .002) and poor RFS (HR: 3.648, 95% CI: 1.986-6.990, p=<.001).
Conclusions:
Preoperative low BMD is closely related to mortality and cancer recurrence after the resection of extrahepatic biliary cancers. BMD screening in patients with cancer should be further highlighted in the oncology field.
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