Mast cell tumours are the most common cutaneous tumours in dogsWithrow, S.J. and Vail, D.M. Small Animal Clinical Oncology, Elsevier Inc, Canada 402-421, 2007.Welle MM, et al. Veterinary Dermatology 2008;19:321–339.McNeil EA, et al. Veterinary and Comparative Oncology 2006;4:2–28.Murphy S, et al. Veterinary Record. 2006;158(9):287–291.
Mast cell tumours (MCTs) are a cancer of mast cells. Mast cells arise in the bone marrow, travelling to sites to mediate an inflammatory response by releasing granules of histamine and heparin. It is not known exactly why mast cells form MCTs, but it happens often enough for this to be the most common form of cutaneous cancer in dogs.
Cytological grading is a relatively new technique that uses a fine needle aspirate sample for grading, making it easier and more time-efficient than histological grading. This technique reports a HIGH or LOW grade for the tumour, based on the criteria similar to the 2-tiered Kiupel histopathological system.Camus, M.S., Priest, H.L., Koehler, J.W., Driskell, E.A., Rakich, P.M., Ilha, M.R. and Krimer, P.M. Cytologic Criteria for Mast Cell Tumour Grading in Dogs With Evaluation of Clinical Outcome. Veterinary Pathology 2016; 53: 1117-1123.
Factors that can make a mast cell tumour non-resectable: