Tumor Cell Implantation from an Oral Advanced Cancer at the Rectal Endoscopic Submucosal Dissection Site: A Case Report and Literature Review.

This report and literature review explores cases of tumor cell implantation at colorectal post-endoscopic resection sites. We detail a unique case in which advanced rectosigmoid colon cancer cells would implant into an endoscopic submucosal dissection (ESD) site in a synchronous upper rectal colon intramucosal cancer. The patient underwent upper rectal ESD prior to surgery for the advanced rectosigmoid colon cancer. After 7 months, a follow-up colonoscopy revealed recurrence at the upper rectal ESD scar, and the patient underwent Miles' operation. The recurrence was confirmed by RAS mutation status to be implantation from the advanced rectosigmoid colon cancer. The literature review, encompassing ten cases, shows that implantation often occurs at rectal post-endoscopic resection sites, with some cases associated with nearby advanced cancers, particularly on the oral side. Four cases suggested implantation from cancer during ESD. These findings underscore the need for caution during colorectal ESD procedures, considering the potential implantation risk. Additionally, early detection of implantation and subsequent curative resection were common outcomes, suggesting the importance of vigilant surveillance. Further research and preventive measures such as thorough intraluminal lavage and complete closure of ulcers may be crucial in minimizing implantation risks post-endoscopic treatment.