Mo1624 CLINICAL VALIDATION OF THE SIMPLE CLASSIFICATION FOR OPTICAL DIAGNOSIS OF DIMINUTIVE AND SMALL COLORECTAL POLYPS

Abstract

one-stage surgical resection. European guidelines have suggested that in younger patients, preoperative stenting may be associated with cancer recurrence and have thus discouraged this practice. We hereby evaluated across five hospitals the outcomes of preoperative colonic stenting with regards to cancer recurrence and ostomy rates. Methods: We identified across five hospitals all patients who underwent preoperative colonic stenting for left-side obstructive CRC from 8/2009 to 8/2019. We further stratified patients based on the absence of distant metastasis at diagnosis to evaluate for recurrence rate. Our two comparator groups were patients who underwent upfront surgery either for obstructive CRC or non-obstructive CRC. Outcomes were gathered through extensive chart review. Recurrence was determined radiographically or pathologically. Results: There were 81 patients who had preoperative stenting for obstructive CRC. The rate of stent-related complication was 10%. There was no statistically significant difference in 6-month or 1-year recurrence rate between the stenting and the two upfront surgery groups (3%, 15%, 5% respectively, p-values 0.156 and 1.00). After accounting for lymphovascular and perineural invasion (LVI/PNI), we observed that stenting was associated with a lower 1-year recurrence rate compared to upfront surgery for obstructive CRC in patients with positive LVI/PNI (6% versus 60%, p-value 0.028). In terms of ostomy rates, the stenting group had a 6-month ostomy rate of 23% and 1-year rate of 16%, compared to 41% and 33% respectively (p-values 0.065 and 0.066) in the upfront surgery for obstructive CRC group, and 32% and 16% respectively (p-values 0.425 and 1.00) in the non-obstructive CRC group. Postoperative infection (12%, 13% and 16% respectively for the three groups), leak (9%, 10% and 4% respectively) and total complication (16%, 15% and 16% respectively) rates were similar in the three groups (p-values all > 0.05). Finally, the median post-colectomy hospital stay was 4 days for the stenting group, compared to 6 days for the upfront surgery for obstructed CRC group (p-value 0.0003). Conclusion: We observed, in our multi-center study, that preoperative stenting was not associated with an increased risk of cancer recurrence in patients with obstructive CRC up to one year following surgery. Length of stay was shorter in the stenting group. Interestingly, despite the goal of one-stage surgery with a colonic stent, one-year ostomy rates were similar in both groups. We demonstrated that preoperative stenting does not impact one-year oncologic outcomes in obstructive CRC, however, preoperative stenting may not achieve the goal of remaining ostomy free.