Comparison of NOSES and Conventional Laparoscopic Surgery in Colorectal Cancer

Inclusion Criteria: * The inclusion criteria were as follows: (1) patients aged between 18 and 80 years; (2) histopathology confirmed as colorectal adenocarcinoma; (3) preoperative imaging (CT and MR) assessments showed that colorectal cancer did not penetrate the serosa (≤T3); (4) tumor circumference \<5 cm; (5) enhanced chest and abdominal pelvic CT scans before operation excluded liver metastasis, lung metastasis, and other distant organ metastases. Exclusion Criteria: * The preoperative exclusion criteria were as follows: (1) tumors could be resected by endoscopic submucosal dissection (ESD) and endoscopic mucosal resection (EMR); (2) body mass index (BMI) \> 30 kg/m2; (3) patients with severe perforation, bleeding, or obstruction requiring emergency surgery; (4) recurrent cases; (5) patients undergoing neoadjuvant therapy or preoperative radiotherapy; (6) Anesthesiologists (ASA) score ≥ IV; (7) active period of infection; (8) blood neutrophils \<3 × 109/L.