Surgical Excision of Primary Canine Rectal Tumors by an Anal Approach in Twenty‐Three Dogs

Objective— To describe an anal approach for excision of primary rectal tumors in dogs and to report outcome. Study Design— Retrospective study. Animals— Dogs (n=23) with primary rectal tumors. Methods— Review of medical records (1990–2000) of dogs with primary rectal neoplasia excised surgically using an anal approach with rectal prolapse. With dogs anesthetized, the rectum was prolapsed, stabilized with stay sutures during tumor excision with 1 cm margins to the level of the muscularis, then the rectal mucosa was sutured. Results— Each dog had only 1 tumor type (adenocarcinoma [8], solitary polyp [5], carcinoma [4], plasmacytoma [2], adenoma [1], leiomyoma [1], mucinous carcinoma [1], and papilloma [1]). Mean tumor volume was 3.1 cm 3 (range 0.1–37.7 cm 3 ). Postoperative complications (rectal bleeding [5], tenesmus [4]) were mild and resolved within 7 days after surgery; another dog had partial mucosal dehiscence identified at 6 days. The primary tumor was incompletely excised in 1 dog (4.3%), and local recurrence occurred 16 and 24 months after surgery in 2 dogs. Outcome beyond the immediate postoperative period was known for 18 dogs, including 2 dogs still alive. Mean postoperative disease‐free interval for these 18 dogs was 36.8 months (range 5–84 months). Conclusion— Surgical excision of tumors of the caudal rectum can be accomplished through the anus after rectal prolapse. Clinical Relevance— An anal approach facilitated by rectal prolapse should be considered as a viable option for the surgical treatment of selected cases of tumors of the caudal aspect of the rectum in dogs.