Statement from the Authors: In preparing this document the Authors aimed to pool current information on canine and feline mast cell disease. The information was gathered from international studies and a emphasis was placed on material and opinion with a strong evidence base. We intend it to form the basis of our understanding in this disease at the current time and we anticipate that it will be particularly useful for the general practitioner. It should be emphasized that the authors are presenting this work from a European perspective.

Objective—To evaluate predictors of survival time in dogs undergoing adrenalectomy and identify risk factors associated with adrenal gland tumor metastasis and vein thrombosis. Design—Retrospective case series. Animals—52 dogs with primary adrenal gland tumors. Procedures—Medical records were reviewed. Signalment, tumor features, and information from surgical procedures were evaluated to identify factors predictive of overall survival time, which was defined as the time from surgery until death. The association between metastasis or vein thrombosis and tumor type, size, and site (right or left adrenal gland) was investigated. Results—On the basis of results of univariate analysis, survival time was significantly shorter for dogs with adenocarcinoma, tumor major axis length ≥ 5 cm, metastasis, and vein thrombosis and when adrenalectomy was combined with an additional abdominal surgical intervention. On multivariate analysis, survival time was significantly shorter for dogs with an adrenal gland tumor with major axis length ≥ 5 cm and for dogs with metastasis or vein thrombosis. Significant associations were found between metastasis and adenocarcinoma and between vein thrombosis and tumors with major axis length ≥ 5 cm. Conclusions and Clinical Relevance—Dogs with an adrenal gland tumor with major axis length ≥ 5 cm, documented metastasis, or vein thrombosis had a poorer prognosis. Metastasis was more frequent in dogs with adenocarcinoma and vein thrombosis when tumors were ≥ 5 cm in length.

Objective—To determine prognostic factors for and compare outcome among dogs with oral malignant melanoma following excision with or without various systemic adjuvant therapies. Design—Retrospective case series. Animals—151 dogs with naturally occurring oral malignant melanomas treated by excision with or without adjuvant therapies from 2001 to 2012. Procedures—Case accrual was solicited from Veterinary Society of Surgical Oncology members via an email list service. Information collected from case records included signalment, tumor staging, tumor characteristics, type of surgical excision, histologic diagnosis, adjuvant therapy, and survival time. Results—The overall median survival time was 346 days. Results of multivariate analysis indicated that tumor size, patient age, and intralesional excision (vs marginal, wide, or radical excision) were considered poor prognostic indicators. All other demographic and clinical variables were not significantly associated with survival time after adjusting for the aforementioned 3 variables. A clear survival benefit was not evident with any systemic adjuvant therapy, including vaccination against melanoma or chemotherapy; however, the number of dogs in each treatment group was small. Ninety-eight dogs received no postoperative adjuvant therapy, and there was no difference in survival time between dogs that did (335 days) and did not (352 days) receive systemic adjuvant therapy. Conclusions and Clinical Relevance—For dogs with oral malignant melanoma, increasing tumor size and age were negative prognostic factors. Complete excision of all macroscopic tumor burden improved survival time. Long-term survival was possible following surgery alone. Although systemic adjuvant therapy was not found to improve survival time, this could have been due to type II error.