S220 Cancer-Specific 5-Year Survival Following Endoscopic Polypectomy versus Surgery for Malignant Colorectal Polyps

Abstract

Introduction: Current guidelines recommend polyp resection strategies, endoscopic resection (ER) or surgical resection (SR) based on high-risk histological features and depth of invasion to ensure complete removal of the malignant lesion, minimizing the risk of progression through micrometastasis. Data comparing cancer-specific survival following ER or SR for localized malignant polyps based on the AJCC staging (Stage 0, I & II & grade) are scarce. Methods: We used the Surveillance Epidemiology and End Results (SEER) database (2004-2015) on patients diagnosed with at least a single malignant colorectal polyp (Table) on the colonoscopies performed for any indication or screening. Data extraction was through a case listing session using SEER*Stat v8.3.9 on combined SEER 18 incidence registries using specific codes for CRC polyps with cancer. Statistical analysis was performed using SPSS v27 for Mac. Results: A total of 63,147 patients with a diagnosis of a colorectal polyp with a malignant component were identified. The mean age was 47.48 years (± 12.15 SD), 45.6% were females. T stages ranged T1-T3. Patients with stage 0 (carcinoma in situ) polyps showed equivalent 5-year cancer-specific survival regardless of ER or SR (mean 170 vs 169 months, 94.2% vs 93.7%, P=0.429, Figure 1A). Stage I and II patients showed superior 5-year survival with SR than ER (mean 165 vs 159 months, 91.1% vs 88%, p< 0.001, Figure 1B). Patients with well-differentiated histological grade demonstrated no survival differences regardless of ER or SR (mean 165 vs 166 months, 92.7% vs 93%, P=0.175, Figure 1C). In contrast, those with polyps of poor differentiation or anaplastic features showed superior 5-year cancer-specific survival with SR than ER (mean 161 vs 145months, 90% vs 88%, P=< 0.001, Figure 1E). Patients with polyps of moderate differentiation showed superior 5-year cancer-specific survival with SR compared with ER (mean 164 vs 159months, 92% vs 90% p< 0.001, Figure 1D) Conclusion: Our results show that cancer-specific survival improved in patients with malignant polyps with AJCC Stage I or II who underwent SR compared with ER, but not Stage 0 (carcinoma in situ). Another novel finding was superior 5-year cancer-specific survival in patients with polyps of moderately-differentiated histological grade, in addition to poorly differentiated and anaplastic grades, which has not been reported before. These novel findings warrant further corroboration from well-constructed clinical trials.Figure 1.: Five-year cancer specific survival comparing endoscopic resection versus surgical resection for colorectal polyps by cancer stage and histological grade.Table 1.: Number of patients diagnosed with polyps with a malignant component by stage and year of diagnosis.