[Endoscopic full-thickness resection in near clinical complete response rectal cancer after neoadjuvant therapy]

Objective: To investigate the safety and feasibility of endoscopic full-thickness resection (EFTR) in the treatment of near-clinical complete response (near-cCR) rectal cancer after neoadjuvant therapy. Methods: A 74-year-old female patient with cT3N0M0 stage rectal adenocarcinoma who refused radical surgery for rectal cancer underwent neoadjuvant chemoradiotherapy (5 cycles of CapeOx chemotherapy and concurrent radiotherapy for 25 sessions) after multidisciplinary team discussion. One month after completing neoadjuvant treatment, reassessment including digital rectal examination, colonoscopy, and pelvic enhanced magnetic resonance imaging suggested near-cCR. Despite this, the patient requested rectal-preserving therapy. Subsequently, EFTR was performed five weeks after completion of neoadjuvant treatment. Postoperatively, supportive care including fasting, antimicrobial therapy, and nutritional support was provided. The patient started a liquid diet on the 6th day postoperatively and was discharged on the 13th day. Results: Pathological analysis revealed tubular adenoma with low-grade epithelial dysplasia, with negative margins and negative involvement of the base. During one-year follow-up, there were no signs of local regrowth or distant metastasis, and satisfactory anal function was observed. Conclusion: EFTR is safe and feasible in patients with near-cCR rectal cancer after neoadjuvant therapy. This approach should be considered after thorough evaluation of the patient's condition.