Effect of a paclitaxel-eluting metallic stent on rabbit esophagus.

The use of self-expanding metallic stents (SEMS) is the current treatment of choice for malignant gastrointestinal obstructions. A paclitaxel-eluting metallic SEMS (PEMS) may have an antitumor effect on esophageal tissue. PEMS with 10% paclitaxel or conventional SEMS were inserted into the lower esophagus of rabbits. Following the insertion of the stents for 1, 2, 4 and 6 weeks, the rabbits were sacrificed and the status of the stent insertion was examined, as well as any macroscopic or microscopic mucosal changes in the esophageal tissue. All the rabbits survived until death without any complications. No migration following stent insertion occurred. The number of cases with proximal obstruction increased in a time-dependent manner, and no significant difference was observed between the two groups. Gross histological examination showed similar tissue reaction to the stents at 1, 2 and 4 weeks, and inflammatory cell infiltrating was higher in the SEMS group at 1 and 2 weeks. However, inflammatory cell infiltration was markedly higher in the PEMS group at 4 and 6 weeks. Food-intake and weight were similar in the two groups. The results of the present study demonstrated that PEMS may serve as a safe alternative treatment strategy for esophageal obstruction. Furthermore, PEMS may inhibit the tumor growth of the esophageal wall through inflammatory infiltration and targeted drug delivery. A tumor model will be required in the future for evaluating the prognosis of patients with advanced esophageal carcinoma.