Postoperative wound surveillance is a key principle of surgery, yet is not traditionally considered at anastomotic wound sites. Here we hypothesized that serial endoscopic examination of low anterior resection (LAR) anastomotic wounds can yield useful information regarding healing.

Patients undergoing LAR with ileostomy for rectal cancer were recruited for study. Patients underwent serial lower endoscopy at three time points during the course of LAR: intraoperatively, before discharge (postoperative day 3-7) and at follow-up (postoperative day 10-28). At each endoscopy, images were captured and anastomotic tissues lavaged for fluid retrieval and analysis. Retrieved fluid samples were analyzed using proteomics, zymography, and ELISA to detect extracellular matrix proteins, inflammatory mediators and bacteria via 16S rRNA gene amplicon sequencing and culture of collagenolytic strains.