Background: Reports of canine anal sac gland carcinoma (ASGC) describe varied clinical presentations and management and differing responses to therapy. A unifying approach to clinical stage determination and management of this disease has yet to be presented.Hypothesis: An ordinal clinical staging scheme for canine ASGC can be devised on the basis of responses to therapy for a retrospective cohort of affected dogs.Animals: 130 dogs with naturally occurring ASGC. Methods: A simplified clinical stage system and a management algorithm for canine ASGC were derived from retrospective evaluation of a cohort of 80 dogs; applicability of both was then prospectively evaluated in a cohort of 50 dogs.Results: Retrospective evaluation revealed 4 statistically significant negative prognostic indicators for survival: lack of therapy, presence of distant metastases, presence of lymph node metastases, and primary tumor size. Lymph node extirpation was a statistically significant positive prognostic indicator by bivariate analysis. In both retrospective and prospective analyses, the modified clinical stage scheme revealed a significant association with survival time.Conclusions and Clinical Importance: The clinical staging scheme permits differentiation between groups in terms of prognosis and, therefore, decisions on therapy. This will facilitate application of appropriate therapy and enhanced communication and collaboration in further investigations of ASGC.

Survival times in this study exceed those in other studies published previously. In part, this is explained by an improved remission duration following surgery compared with previous reports. More striking though is the longevity of patients following institution of medical therapy. These data give strong objective support to the role of medical therapy in the management of canine insulinoma, including following relapse after surgically induced remission.

The results of this retrospective study indicate that many spindle cell tumours managed in first opinion practice exhibit a low-grade biological behaviour and may respond well to more conservative surgery than current recommendations advise.

Objective To determine outcome of dogs with a diagnosis of soft tissue sarcoma managed in first opinion practice. Study Design Retrospective, case‐controlled study Animals Dogs (n = 350) with primary occurrence of a soft tissue sarcoma. Methods A previously validated questionnaire was sent to all veterinarians requesting clinical information and ultimate outcome for all dogs. Histologic sections were reviewed by a single pathologist. Results Most surgeries were unplanned, with only 15 (4%) dogs having a histologic and 59 (16.8%) dogs having a cytologic diagnosis before surgery. Median survival time for all dogs was not reached with 70% proportional survival at 5 years. Local recurrence developed in 73 (20.8%) cases. The extent of resection performed was not associated with improved survival (P = .2) or tumor recurrence (P = .8). Age <8 years (χ2 = 6.1; P = .01), tumors <5 cm in size (χ2 = 9.6; P = .002) and discrete tumors (χ2 = 16.6; P < .001) had improved survival outcomes. On multivariate analysis, a high tumor grade was significant for recurrence (HR 5.8; P < .001; 95% CI: 2.2–14.8). Evidence of a selection bias towards less aggressive tumors being managed in first opinion practice was confirmed. Conclusions Wide resection margins are not the primary determinant of outcome for all soft tissue sarcoma. Veterinarians need to better understand the biologic behavior of a suspected soft tissue sarcoma before treatment to allow surgical margins to be adjusted accordingly.