Surgery outcomes for dogs with metastatic anal sac cancer

Abstract

Objective— To identify survival and morbidity information after surgery for metastases from apocrine gland anal sac adenocarcinomas (AGACA).Study Design— Retrospective study.Animals— Five dogs with AGACA.Methods— Medical records of dogs that had surgery for treatment of metastatic AGACA between 1993 and 2003 were reviewed. Criteria for inclusion required that dogs had lymphadenectomy, with or without further debulking, as part of their treatment for metastatic AGACA and that the tissue was histologically confirmed as consistent with the primary AGACA. Signalment, history, physical examination findings, clinicopathologic data, imaging findings, surgical complications, number of surgeries, survival times, and cause of death were recorded. All dogs had a complete blood count, serum biochemical profile, serum electrolytes, 3‐projection thoracic radiographs, abdominal radiographs and/or abdominal ultrasonography, and histologic confirmation of metastatic AGACA invading the regional lymph nodes and caudal abdomen.Results— No surgical complications occurred. Three dogs were euthanatized; median survival, 20.6 months. One dog was alive for 19 months postoperatively. One dog had 5 sequential surgical procedures: 1 iliac lymphadenectomy and 4 debulking procedures of metastatic neoplastic tissue around and dorsal to the iliac vessels extending into the pelvic cavity, and was alive 54 months after initial surgery.Conclusion— Dogs with anal sac adenocarcinoma metastases to the iliac lymph nodes can experience long‐term survival after surgical excision of the metastatic lesion.Clinical Relevance— Lymphadenectomy may afford long‐term survival to patients with metastatic anal sac adenocarcinoma.