Background: Local surgical excision of T1 rectal adenocarcinoma is a well-established approach. Yet, there are still open questions regarding the recurrence rates and its risk factors. Methods: A retrospective multicenter study including all patients who underwent local excision of early rectal cancer with an open or MIS approach and had a T1 lesion from 2010 to 2020 in six academic centers. Data included demographics, preoperative studies, surgical findings, postoperative outcomes, and local and systemic recurrence. A univariable and multivariable logistic regression analysis was performed to identify risk factors for recurrence. Results: Overall, 274 patients underwent local excision of rectal lesions. Of them, 97 (35.4%) patients with a T1 lesion were included in the cohort. The mean age was 69 ± 10.5 years, and 42 (43.3%) were female. The mean distance of the lesions from the anal verge was 7.8 ± 3.2 cm, and the average tumor size was 2.7 ± 1.6 cm. Eighty-two patients (85%) had a full-thickness resection. Eight patients (8%) had postoperative complications. Kikuchi classification of submucosal (SM) involvement was reported in 29 (30%) patients. Twelve patients had SM1, two SM2, and fifteen SM3. Following pathology, 24 patients (24.7%) returned for additional surgery or treatment. The overall recurrence rate was 14.4% (14 patients), with 11 patients having a local recurrence and 6 having a systemic metastatic recurrence, 3 of which had both. The mean time for recurrence was 2.78 ± 2.8 years and the overall mortality rate was 11%. On univariable and multivariable logistic regression analysis of recurrence vs. non-recurrence groups, the strongest and most significant association and possible risk factors for recurrence were larger lesions (4.3 vs. 2.5 cm, p < 0.001) with an OR of 6.67 (CI—1.82–24.36), especially for tumors larger than 3.5 cm, mucinous histology (14.3% vs. 1.2%, p = 0.004, OR of 14.02, CI—1.13–173.85), and involved margins (41.7% vs. 16.2%, p = 0.003, OR of 9.59, CI—2.14–43.07). The open transanal excision (TAE) approach was also identified as a possible significant risk factor in univariant analysis, while SM3 level penetration showed only a trend. Conclusion: Surgical local excision of T1 rectal malignancy is a safe and viable option. Still, one in four patients received additional treatment. There is an almost 15% chance for recurrence, especially in large tumors, mucinous histology, or involved margin cases. These high-risk patients might warrant additional intervention and stricter surveillance protocols.

Purpose: Rectal polyps with low-grade dysplasia (LGD) can be removed by local excision surgery (LE). It is unclear whether these lesions pose a higher risk for recurrence and cancer development and might warrant an early repeat rectal endoscopy. This study aims to assess the rectal cancer rate following local excision of LGD rectal lesions. Methods: A retrospective multicenter study including all patients that underwent LE for rectal polyps over a period of 11 years was conducted. Demographic, clinical, and surgical data of patients with LGD werecollected and analyzed. Results: Out of 274 patients that underwent LE of rectal lesions, 81 (30%) had a pathology of LGD. The mean patient age was 65 ± 11 years, and 52 (64%) were male. The mean distance from the anal verge was 7.2 ± 4.3 cm, and the average lesion was 3.2 ± 1.8 cm. Full thickness resection was achieved in 68 patients (84%), and four (5%) had involved margins for LGD. Nine patients (11%) had local recurrence and developed rectal cancer in an average time interval of 19.3 ± 14.5 months, with seven of them (78%) diagnosed less than two years after the initial LE. Seven of the nine patients were treated with another local excision, whilst one had a low anterior resection, and one was treated with radiation. The mean follow-up time was 25.3 ± 22.4 months. Conclusions: Locally resected rectal polyps with LGD may carry a significant risk of recurring and developing cancer within two years. This data suggests patients should have a closer surveillance protocol in place.