Current roles of colonoscopy in minimally invasive colorectal surgery: Preoperative guidance, intraoperative colonoscopy, and combined endoscopic-laparoscopic surgery.

Colonoscopy is a cornerstone in the detection and diagnosis of colorectal tumors, playing a critical role in both screening and clinical evaluation. More recently, its utility has expanded to therapeutic guidance, particularly with the advent of minimally invasive surgical techniques. Preoperative tattoo marking is commonly used for tumor localization; however, it poses challenges such as intraperitoneal ink scattering and difficulty in defining dissection planes in the lower rectum. To address these limitations, a new technology utilizing a near-infrared fluorescence clip placed preoperatively enables accurate intraoperative tumor localization. Intraoperative colonoscopy offers additional advantages, including real-time tumor localization, colonic irrigation, visualization of the proximal colon in obstructive cases, and assessment of anastomosis following colorectal resection. Notably, intraoperative colonoscopy allows for the immediate detection and management of complications, such as anastomotic bleeding and leakage, potentially improving postoperative outcomes. Furthermore, advances in endoscopic resections, including endoscopic mucosal resection, endoscopic submucosal dissection, hybrid endoscopic submucosal dissection, and combined endoscopic laparoscopic surgery, have broadened the indications for endoscopic and endoscopy-guided full-thickness resection of colorectal tumors. These approaches are increasingly applicable beyond conventional colorectal neoplasms and show promise in managing appendiceal tumors as well.