Antireflux Metal Stent for Initial Treatment of Malignant Distal Biliary Obstruction.

Objectives: To compare the use of an antireflux metal stent (ARMS) with that of a conventional covered self-expandable metal stent (c-CSEMS) for initial stenting of malignant distal biliary obstruction (MDBO).

Materials and Methods: We retrospectively investigated 59 consecutive patients with unresectable MDBO undergoing initial endoscopic biliary drainage. ARMS was used in 32 patients and c-CSEMS in 27. Technical success, functional success, complications, causes of recurrent biliary obstruction (RBO), time to RBO (TRBO), and reintervention were compared between the groups.

Results: Stent placement was technically successful in all patients. There were no significant intergroup differences in functional success (ARMS [96.9%] versus c-CSEMS [96.2%]), complications (6.2 versus 7.4%), and RBO (48.4 versus 42.3%). Food impaction was significantly less frequent for ARMS than for c-CSEMS ( P = 0.037), but TRBO did not differ significantly between the groups (log-rank test, P = 0.967). The median TRBO was 180.0 [interquartile range (IQR), 114.0-349.0] days for ARMS and 137.0 [IQR, 87.0-442.0] days for c-CSEMS. In both groups, reintervention for RBO was successfully completed in all patients thus treated.

Conclusion: ARMS offers no advantage for initial stent placement, but food impaction is significantly prevented by the antireflux valve.