Evaluation of covered metallic stents in malignant biliary stenosis - Prominent effectiveness in gallbladder carcinoma

Background/Aims: The survival time of patients with unresectable malignant biliary stenosis and the patent period of metallic biliary stents are different in each disease. The efficacy of the covered metallic stent was analyzed according to the primary disease. Methodology: Seventy-three patients with bile duct carcinoma (12 cases), gallbladder carcinoma (22 cases), and pancreas carcinoma (39 cases) were retrospectively enrolled. Covered metallic stents were used in 42 patients and uncovered metallic stents in 31 patients. The patency of covered stents was compared with that of uncovered stents for each disease. Results: The patent rate at 6 months after insertion was 80.6% (95% CI [72.6%, 88.6%]) for the covered stent, and 49.5% (95% CI [37.6%, 61.4%]) for the uncovered stent. The mean patent periods of the covered stent and the uncovered stent were 14.6 and 27.6 months for bile duct carcinoma (p=0.424), 12.7 and 3.0 months for gallbladder carcinoma (p=0.003), and 11.9 and 9.6 months for pancreas carcinoma (p=0.919), respectively. Conclusions: The covered metallic stent was the most effective in patients with gallbladder carcinoma.