Prognostic factors and complications attributed to surgical resection of cutaneous mast cell tumors in 62 dogs attended in UNESP-Jaboticabal veterinary hospital from 2013 to 2019

Mast cell tumors, which are neoplasms with variable behavior, from less aggressive to highly metastatic tumors, account for 16%–21% of cutaneous neoplasms in dogs. The diagnosis and grading of mast cell tumors are based on cytological analysis and histological evaluation, which facilitate appropriate planning for surgical and chemotherapeutic treatment. Surgical resection with safety margins of 2–3 cm is considered the best therapeutic option; however, postoperative complications, such as delayed healing, necrosis, suture dehiscence, and occurrence of seroma, are reported. It is essential to understand the biology of mast cell tumors because prognostic factors directly influence the efficacy of the treatment and the quality of life of the patient. Here, we conducted a retrospective study of dogs submitted to surgical resection of cutaneous mast cell tumors, and analyzed the prognostic factors and occurrence of postoperative complications. The results showed that low grade mast cell tumors were associated with a lower occurrence of ulceration, metastasis, recurrence, lack of need for adjuvant therapy, and occurrence of paraneoplastic syndrome compared to those of a higher grade. We also compared the association between demanding or compromised margins with the presence of postoperative complications. The results showed that high grade mast cell tumors have a greater metastatic potential and that the presence of neoplastic cells in the adjacent tissues leads to a greater malignancy and postoperative complications.