Long-Term Oncologic Safety Of Self-Expandable Metal Stent As A Bridge To Surgery For Malignant Colorectal Obstruction: Our Experience

153 Background: About 10-25% patients of colorectal cancer suffer from acute colonic obstruction. Traditional management of acute malignant bowel obstruction has focused on emergency resection but showed high mortality and morbidity rates. Recently, placement of a self-expanding metal stent(SEMS) was widely used and SEMS seems to be as a safe and effective “bridge to surgery” and to offer good palliation. But there is concern about long-term survival after the use of SEMS. Theoretically, tumor cell seeding can occur due to mechanical force during the stent insertion. To identify this theoretical validity, we surveyed long-term survival of malignant colonic obstruction using SEMS placement. Methods: This retrospective study included 303 patients who presented in Korea University Anam Hospital between 2006 and 2014 with obstructing CRC, and underwent surgical resection. Patients were devided into two group: the “SEMS” group included 148 patients who underwent endoscopic stent as a bridge to surgery, and the surgery group included 155 patients who underwent emergency or elective surgery without stenting. In addition, candidates for curative resection were identified (98 patients in “SEMS” group vs 101 patients in “surgery” group). The clinicopathologic characteristics, overall survival(OS), and recurrence-free survival (RFS) were compared between the two groups. Results: There was no significant difference in demographics, tumor stage between the two group. The median follow-up times were 48.5 months (IQR, 19.1-73.1 months) for the SEMS group and 39.4 months (IQR, 15.1-39.4 months) for the surgery group. There was no significant difference in 5-year OS rate between two groups (59.6% vs 56.8%; p = 0.3). The 5-year RFS rate did not significantly differ between two groups (71.0% vs. 61.3%; p = 0.221). The long-term oncologic safety did not significantly differ between two groups in either the 5-year OS rate (79.5% vs 74.5%; P= 0.6). or the 5-year RFS rate (95.8% vs 95.8%; P = 0.3). Conclusions: SEMS as bridge to surgery in obstructive CRC did not worsen the long-term oncologic outcomes compared to those of the primary surgery.