Surgical excision of anal sac apocrine gland adenocarcinomas with and without adjunctive chemotherapy in dogs: 42 cases (2005–2011)

Abstract

Objective-To identify variables associated with prognosis in dogs undergoing surgical excision of anal sac apocrine gland adenocarcinomas (ASACs) with and without adjunctive chemotherapy. Design-Retrospective case series. Animals-42 dogs with ASACs. Procedures-Information on signalment, clinical signs, diagnostic procedures, surgical procedures, adjunctive therapies, survival time, and disease-free interval was obtained from the medical records. Results-Survival time was significantly associated with the presence of sublumbar lymphadenopathy and sublumbar lymph node extirpation, with median survival time significantly shorter for dogs with sublumbar lymphadenopathy (hazard ratio, 2.31) than for those without and for dogs that underwent lymph node extirpation (hazard ratio, 2.31) than for those that did not. Disease-free interval was significantly associated with the presence of sublumbar lymphadenopathy, lymph node extirpation, and administration of platinum-containing chemotherapeutic agents, with median disease-free interval significantly shorter for dogs with sublumbar lymphadenopathy (hazard ratio, 2.47) than for those without, for dogs that underwent lymph node extirpation (hazard ratio, 2.47) than for those that did not, and for dogs that received platinum-containing chemotherapeutic agents (hazard ratio, 2.69) than for those that did not. Survival time and disease-free interval did not differ among groups when dogs were grouped on the basis of histopathologic margins (complete vs marginal vs incomplete excision). Conclusions and Clinical Relevance-Results suggested that in dogs with ASAC undergoing surgical excision, the presence of sublumbar lymphadenopathy and lymph node extirpation were both negative prognostic factors. However, completeness of surgical excision was not associated with survival time or disease-free interval.

Prognostic significance of histopathology in canine anal sac gland adenocarcinomas: Preliminary results in a retrospective study of 39 cases

“…The prognostic significance of the histopathological margins has been investigated in another study performed on dogs undergoing surgical excision of ASGAC with and without adjunctive chemotherapy . No significant differences in survival time or disease‐free interval were found between dogs with complete vs marginal vs incomplete excision.…”

“…However, variability of tumour behaviour is suspected as some dogs may present with large primary tumours without overt metastatic disease, whereas others may have a very small primary tumour already metastatic to distant sites . This is supported by variable rates of metastasis reported in the literature, ranging from 26% to 79% at the time of tumour diagnosis …”

“…In previous studies, several factors have been identified as negative prognosticators for dogs with ASGAC, including increasing primary tumour size, presence of lymph node metastasis, presence of distant metastasis and lack of therapy . The prognostic influence of hypercalcaemia (reported to occur in 16%‐53% of the cases) remains controversial, with some studies showing significantly decreased survival with hypercalcaemia, while others found no predictive value …”

Evaluation of toceranib for treatment of apocrine gland anal sac adenocarcinoma in dogs

“…Based on the multivariable Cox hazard model, toceranib treatment in the microscopic disease setting was associated with prolonged PFS but not with OST (Table ). Prolonged survival in dogs that had surgical treatment of AGASACA has been well documented in the veterinary literature . Furthermore, positive outcomes have been reported in dogs treated surgically, even in cases of metastatic disease .…”

Novel Fiber-rich Supplement Effective for Prevention and Treatment of Acute, Episodic and Chronic Anal Gland Disease in Dogs and Cats

“…• Mildly impacted or irritated anal glands: simple digital pressure to empty the contents • Infected or severely inflamed anal glands: antibiotics, pain and anti-inflammatory medications • Abscesses: surgical curettage, drainage and wound care at home, with antibiotics • Frequently recurring problems or possible neoplastic masses: surgical intervention [17] by a specialist and anal gland removal…”