matinib Mesylate for the Treatment of Canine Mast Cell Tumors: Assessment of the Response and Adverse Events in Comparison with the Conventional Therapy with Vinblastine and Prednison

Author(s)

Macedo, Thais Rodrigues ^[1] ; de Queiroz, Genilson Fernandes ^[2] ; Casagrande, Thais Andrade Costa ^[3] ; Alexandre, Pamela Almeida ^[4] ; Brandao, Paulo Eduardo ^[4] ; Fukumasu, Heidge ^[5] ; Melo, Samanta Rios ^[1] ; Dagli, Maria Lucia Zaidan ^[6] ; Pinto, Ana Carolina B. C. Fonseca ^[1] ; Matera, Julia Maria ^[1]

Affiliation

^[1] Univ Sao Paulo, Sch Vet Med & Anim Sci, Dept Surg, BR-05508010 Sao Paulo - Brazil

^[2] Fed Rural Univ Semiarid, Dept Anim Sci, BR-59625900 Mossoro - Brazil

^[3] Posit Univ, Masters & Doctors Degree Program Ind Biotecnol, BR-81280330 Curitiba, Parana - Brazil

^[4] Univ Sao Paulo, Sch Vet Med & Anim Sci, Dept Prevent Vet Med & Anim Hlth, BR-05508010 Sao Paulo - Brazil

^[5] Univ Sao Paulo, Fac Anim Sci & Food Engn, Dept Vet Med, Lab Comparat & Translat Oncol LOCT, BR-13635900 Pirassununga - Brazil

^[6] Univ Sao Paulo, Sch Vet Med & Anim Sci, Dept Pathol, Lab Expt & Comparat Oncol, BR-05508010 Sao Paulo - Brazil

• Document type: Journal article
• Source: ELL; v. 11, n. 3 FEB 2022.
• Web of Science Citations: 0

Abstract

Mast cell tumors (MCTs) are common neoplasms in dogs, and treatments for these diseases include surgery, polychemotherapy and targeted therapy with tyrosine kinase inhibitors. This study aimed to evaluate the response and the adverse events of treatment with imatinib mesylate (IM) compared to conventional therapy using vinblastine and prednisolone (VP) in canine cutaneous MCTs. Twenty-four dogs were included in the study; 13 animals were treated with IM and 11 with VP. Tumor tissue samples were submitted for histological diagnosis, grading and KIT immunostaining. The response to treatment was assessed by tomographic measurements according to VCOG criteria. Adverse events were classified according to VCOG-CTCAE criteria. The IM and VP groups had dogs with similar breeds, gender, ages, MCT localization, WHO stages and lymph node metastasis profiles. Most MCTs were grade 2/low and had KIT- patterns 2 and 3. The objective response rate (ORR) was significantly higher (30.79%) in the IM group then in VP group (9.09%). Adverse events (AE) in IM group were all grade 1, significantly different from VP. In conclusion, IM presented better ORR and less severe adverse events when compared to VP, representing a suitable option for the treatment of low-grade canine MCTs. (AU)

• FAPESP's process: 10/15093-6 - Comparison of the effectiveness of protocols with imatinib mesylate, and vinblastine with prednisone, prednisone in the treatment of canine mastocytoma-clinical, surgical, histopathological, immunohistochemical and molecular study
• Grantee: Thaís Rodrigues Macedo
• Support Opportunities: Scholarships in Brazil - Doctorate