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Screw-thread vs Dumon endoprosthesis in the management of tracheal stenosis.

STUDY OBJECTIVES
A frequent complication of the widely used Dumon silicone stent is its tendency to migrate when used in tracheal stenosis. We compared the clinical efficacy and complications (including migration) of the Dumon stent with a screw-thread stent, a device with an increased stent-to-wall contact surface and, theoretically, less tendency to migrate.


DESIGN
Retrospective case analysis.


SETTING
Academic hospital.


MATERIALS AND METHODS
Forty-six patients with tracheal stenoses (23 benign and 23 malignant) requiring the placement of 50 stents (29 Dumon and 21 screw-thread) were studied. In 26 patients Dumon stents were used, and in 20 patients screw-thread stents were used. Both patient groups had comparable clinical and stenosis-related characteristics.


RESULTS
Stent insertion and follow-up were uneventful in both the Dumon and the screw-thread insertions, respectively: 62% vs 67% (not significant). There were seven migrations in the Dumon group, compared to only one migration in the screw-thread group, respectively: 24% vs 5%. This difference did not reach statistical significance (p = 0.1). All of the migrations occurred in the benign stenosis group, and none occurred in the malignant-stenosis group, respectively: 8 of 23 vs 0 of 23, p = 0.004. Within the benign-stenosis group, the Dumon stent had a significantly increased risk for migration when compared to the screw-thread stent, respectively: 7 of 13 vs 1 of 11, p = 0.033.


CONCLUSIONS
The screw-thread stent and the Dumon stent are equally effective in the management of tracheal stenosis. There is a general trend toward a decreased migration rate, and a significantly lower risk for migration in patients with benign tracheal stenosis. The (less expensive) screw-thread stent may represent an attractive alternative in the management of tracheal stenosis in general, and may be preferable to the Dumon stent in treating benign tracheal stenosis.