NEOADJUVANT CHEMORADIOTHERAPY WITH LOCAL EXCISION FOR T2 AND T3 RECTAL CANCERS- MOVING TOWARDS A STANDARD OF CARE
John H. Marks, Hela Saidi, Taylor Ikner, Thais Reif De Paula, Deborah S. Keller*
Lankenau Institute for Medical Research, Wynnewood, PA
Background: Local excision (LE) with transanal endoscopic microsurgery (TEM) is an established alternative to radical resection in select early rectal cancers and high-risk patients. Recent studies demonstrated adding neoadjuvant chemoradiotherapy (NACRT) before LE achieved organ preservation with similar short-term survival to radical resection for cancers up to T2N0. Study on long-term recurrence, survival, and wider application is warranted. We sought to evaluate oncologic and survival outcomes for T2 and T3 rectal cancers treated with NACRT followed by TEM. Our hypothesis was that NACRT with TEM can achieve optimal oncologic outcomes and long-term survival in T2 and T3 rectal cancers.
Methods: A prospective institutional cancer registry was reviewed for clinical stage T2 and T3 rectal adenocarcinoma patients who received NACRT then TEM for curative resection between 1997-2022. Demographics, clinical, and pathological outcomes were evaluated by univariate analysis. Kaplan-Meier analysis assessed recurrence and survival data. The main outcome measure was local recurrence rate (LR) after TEM. Secondary outcomes were disease-free survival (DFS), overall survival (OS), morbidity, and mortality.
Results: 137 cases- 81 T2 [59%] and 56 T3 [41%] were analyzed. Patients were 66.4% male (n=91) with a mean age of 67.7 (SD 12.1). Mean tumor distance from the anorectal ring was 3.2cm (SD 2.5). 88% (n=103) had a good response to NACRT (Tumor Regression Grade 1-2). R0 resection was obtained in 99.2% (n=136). The overall morbidity rate was 29.2% (n=40). There were 3 (2.2%) reoperations for wound dehiscence, intraperitoneal hemorrhage, and rectal bleeding. There was no 30-day mortality. Ten patients required total mesorectal excision (TME) after TEM, with 2 immediately for high risk disease. In these patients, the TEM functioned like a diagnostic full thickness bioipsy. Four patients required TME due to local recurrence of disease, 1 patient's post-surgical pathology demonstrated ypT3Nx cancer, 1 developed significant stenosis, 1 elected to have an abdominoperineal resection, and 3 patients were risk averse and choose TEM to be conservative. After a median follow-up of 46.5 (IQR 15.7-94.6) months, 5 patients (3.6%) developed isolated LR (median time: 34 months) and 11 (8.0%) developed distant metastasis (median time: 25 months). The 3-year OS was 86.8% and DFS was 92.7%.
Conclusions: Using NACRT with TEM has excellent clinical and oncologic outcomes in locally advanced rectal cancers. Long-term outcomes found low rates of LR, low rate of patients that go on to TME, and survival comparable or superior to transabdominal resection rates. While controlled studies are needed, this organ-preserving option is safe, feasible, and requires consideration as an option for all patients in the shared decision-making process for clinically-staged T2/T3 rectal cancers.
Back to 2023 Abstracts