Risk of permanent stoma after resection of rectal cancer depending on the distance between the tumour lower edge and anal verge.

The distance between the anal verge and lower edge of rectal cancer is one of the most important factors affecting the feasibility of sphincter-preserving resection.The aim of the study was to assess the risk of permanent stoma after resection of rectal tumour depending on the distance between the tumour and the anal verge.Material and methods. The retrospective analysis covered 884 patients after resection of rectal cancer. The distance between the anal verge and the lowest edge of the tumour was measured during endoscopic examination. Surgical technique was similar in all cases. For statistical analysis, the chi-square test and Fisher exact test were used.Results. The overall rate of sphincter-preserving procedures was 71.8%, 90.1% of which were anterior resections. The greatest differences between the rate of anterior resections were noted for the segment between the 4th and the 5th centimetres: 30.1% for 4 cm vs 66.7% for 5 cm, p = 0.005. Overall, in 328 patients (37.1%) surgical treatment resulted in a permanent stoma. The number included: 246 (75.0%) patients after abdominosacral resection, 44 (13.4%) patients after the Hartmann procedure, three (0.9%) patients after proctocolectomy, and 28 (8.5%) patients after anterior resection, with a permanent stoma as a result of anastomotic leak. The overall rate of anastomotic leak was 11.7%. Formation of a defunctioning stoma in patients with a low-lying (6 cm from the anal verge) tumour reduced the risk of symptomatic anastomotic leak: 6.3% vs 20.5%; p = 0.049.Conclusions. Anterior resection of tumours located 6 cm from the anal verge is feasible in 90%. Anastomotic leak that requires reoperation increases the risk of permanent colostomy. In selected cases, formation of a defunctioning stoma after resection of low-lying rectal cancer can reduce the risk of permanent colostomy.