In this article, the study's authors review the clinical signs, diagnosis, staging, treatment, and prognosis of apocrine gland anal sac adenocarcinoma (AGASAC) in dogs. AGASAC is a relatively uncommon tumor in dogs and comprises approximately 17% of perianal malignancies. It is, however, one of the most common causes of paraneoplastic hypercalcemia.
Clinical signs in affected dogs most commonly are associated with mechanical obstruction caused by the primary tumor or enlarged regional metastatic lymph nodes and the effects of paraneoplastic hypercalcemia when present. Surgical excision of the primary tumor and metastasectomy of the affected locoregional lymph nodes is the preferred initial treatment option for most dogs, although radiation therapy and adjuvant chemotherapy are commonly incorporated into multi-modality treatment plans.
A significant role for the use of adjuvant chemotherapy has not been clearly demonstrated. Prolonged survival times are possible, especially for dogs with smaller primary tumors and for dogs that undergo further treatments for recurrent disease.
“Canine Apocrine Gland Anal Sac Adenocarcinoma: A Review.” Alec B Repasy, et al. Top Companion Anim Med. 2022 Jul 2;100682. doi: 10.1016/j.tcam.2022.100682.