Perspective Randomized-controlled clinical trial in patients submitted to self-expanding metal stents for colo-rectal cancer with bowel obstruction. Single center experience. Preliminary data

Introduction: Since the early 1990s, self- expanding metal stents (SEMS) have been used to treat malignant colonic obstruction. This kind of endoscopic procedure is mostly used for palliative treatment of colo-rectal cancer buti it is also used as “bridge to surgery”. Materials and methods: This perspective randomized-controlled clinical trial was performed from January 2017 to October 2019. We have recruited all patients admitted in our Emergency Hospital with diagnosis of colonic obstruction. All patients submitted to CT-scan. Patients was divided in 3 Groups: Group A (control group, composed by patients submitted only to emergency surgery) were 17; Group B (patients submitted to SEMS positioning and surgery) were 10; Group C (patients submitted to only SEMS positioning) were 14. The same Metal stent was used for all patient submitted to SEMS positioning (Colonic WallflexTM Boston Scientific 9 cm). Results: Analysis of comparison between Group A vs B highlighted statistical significance for diverting stoma performe (p-value: one-tailed 0.00035; two-tailed 0.00075; p<0.001), equal 70,5% of patients (12 out of 17). Also the comparison between Group A and B, in relation of survival rate (13 patients out of 17, equal to 70,58% in Group A and 10 patients out of 10, equal to 100%, in Group B after two years follow-up), statistical significance shows (p-value one-tailed 0.0010; two- tailed; p<0.005). Comparison of Group B plus C (24 patients), submitted to SEMS, shows time procedure was 25,17 minutes (range 10 - 40) and nobody patients showed stent dislocation or bowel obstruction signs after 48 h from endoscopic procedure. 1 case of Tenesmo in rectal SEMS and 2 colonic perforation after 73 days and 15 days (8%). They submitted early food intake. In our clinical controlled trial, even if is a preliminary data, demonstred that SEMS positioning is a the best palliative procedure with high success rate (95,8%) and a good survival. Mean days of hospitalization of 3,4 days. Conclusion: Our clinical randomized trial shows that SEMS positioning is feasibility as palliative therapy for obstructive colo-rectal cancer and it’s safe procedure as “bridge to surgery”. Other patients are ruled but a greater follow-up will be necessary to make our study more effective.