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Through-the-scope double colonic stenting in the management of inoperable proximal malignant colonic obstruction: a pilot study.

BACKGROUND AND STUDY AIMS
Particularly in cases of proximal colonic obstruction, the long distance and tortuosity of the bowel make it difficult for gastroenterologists and radiologists to advance the stent to the point of the obstruction. The purpose of this study was to evaluate the clinical usefulness and efficacy in preventing stent migration and tumor ingrowth of a new self-expanding through-the-scope (TTS) double colonic stent in the palliative management of patients with inoperable proximal malignant colonic obstruction.


PATIENTS AND METHODS
A total of seven patients (four men, three women; mean age 62 years, range 57 - 68) underwent placement of a newly developed through-the-scope self-expanding double colonic stent. The etiologies of the obstructions at the time of stent insertion were colonic adenocarcinoma (no previous surgical resection) in five cases and metastatic adenocarcinoma from gastric carcinoma in two. The locations of the obstructions were the ascending colon in three cases, the hepatic flexure in two, and the transverse colon in two. To prevent tumor ingrowth and stent migration, an uncovered Niti-S stent (Taewoong Medical Co., Ltd., Seoul, South Korea) was inserted into the stenotic area; a partly membrane-covered Niti-S stent was then again inserted into the stenotic area inside the uncovered Niti-S stent.


RESULTS
The self-expanding TTS double colonic stents were placed in the colon in seven patients with acute malignant colonic obstruction. Double stenting was successful in traversing the lesion in six of the seven cases. In one patient, the stent was not successfully placed across the lesion due to a very acute angle at the hepatic flexure. There were no significant complications relating to the insertion, with no clinical or radiographic evidence of perforation or bleeding during or after the procedures, and there were no cases of stent migration or tumor ingrowth during the mean follow-up period of 13 months.


CONCLUSIONS
Placement of these new self-expanding through-the-scope double colonic stents for the management of inoperable proximal malignant colonic obstruction is a feasible, effective, and safe form of palliative treatment for the prevention of stent migration and tumor ingrowth.