Outcome and clinical, pathological, and immunohistochemical factors associated with prognosis for dogs with early-stage anal sac adenocarcinoma treated with surgery alone: 34 cases (2002–2013)

Abstract

OBJECTIVE To determine survival time and metastatic rate for dogs with early-stage anal sac adenocarcinoma (ASACA) treated with surgery alone and assess whether specific clinical, pathological, or immunohistochemical factors were predictive of outcome for those dogs. DESIGN Retrospective case series. ANIMALS 34 dogs with early-stage, nonmetastatic ASACA that were treated with surgery only. PROCEDURES Medical record databases of 2 referral hospitals were searched to identify dogs examined between 2002 and 2013 that had a diagnosis of nonmetastatic ASACA that was < 3.2 cm at its largest diameter. Only dogs that received surgical treatment alone were included in the study. For each dog, information extracted from the medical record included signalment, clinical and diagnostic test findings, tumor characteristics, and outcome. When available, archived tumor specimens were histologically reviewed and tumor characteristics were described; Ki-67 and E-cadherin expressions were evaluated by use of immunohistochemical methods. Clinical, pathological, and immunohistochemical factors were assessed for associations with survival time and tumor recurrence and metastasis rates. RESULTS Median survival time was 1,237 days. Seven dogs had tumor recurrence and 9 dogs developed metastatic disease at a median of 354 and 589 days, respectively, after primary tumor removal. Cellular pleomorphism was positively associated with development of metastatic disease. No other factors evaluated were associated with outcome. CONCLUSIONS AND CLINICAL RELEVANCE Results indicated dogs with early-stage nonmetastatic ASACA generally had a favorable outcome following surgical removal of the primary tumor alone. Routine rectal examination may be a simple and useful method for detection of dogs with early-stage ASACA.

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 .…”

Comparison of methods to determine primary tumour size in canine apocrine gland anal sac adenocarcinoma

“…, Skorupski et al . ). We analysed variables to determine associations with metastasis at presentation and tumour variables.…”

“…This mirrors the findings of a previous study that did not find an association between MI and long‐term outcome (Skorupski et al . ).…”

“…, Skorupski et al . ). Emerging positive outcome evidence for more stage‐specific treatment highlights the importance of accurate primary tumour measurements to determine stage.…”

“…The reasons for these variations may include delayed diagnosis, variability in imaging (i.e. radiography, ultrasonography, computed tomography (CT) and MRI), regional lymph node sampling technique (aspirates versus biopsy), sample size, follow-up and lack of standardisation in treatment and restaging (Goldschmidt & Zoltowski 1981, Meuten et al 1981, Bennett et al 2002, Turek et al 2003, Williams et al 2003, Emms 2005, Hobson et al 2006, Anderson et al 2015, Potanas et al 2015, Palladino et al 2016, Meier et al 2017, Pollard et al 2017, Skorupski et al 2018. proposed a clinical staging scheme based on primary tumour size, locoregional lymph node size and presence of metastasis.…”