Impact of Toceranib Phosphate and Carprofen on Survival and Quality of Life in Dogs with Inflammatory Mammary Carcinomas

Canine inflammatory mammary carcinoma (IMC) is an aggressive and rare type of mammary gland cancer in dogs where vascular endothelial growth factor and cyclooxigenase-2 overexpression usually occur, which contribute to its invasive and angiogenic nature. This study aimed to evaluate the efficacy and safety of a combined treatment regimen of toceranib phosphate and carprofen in dogs with measurable IMC. Fifteen female dogs with histopathologically confirmed IMC were included, undergoing a regimen of toceranib (2.4-2.75 mg/kg PO, three times weekly) and carprofen (4.4 mg/kg/24 h PO). Initial evaluations included physical exams, tumor measurements, complete blood count, biochemistry, urinalysis, three view thoracic radiographs, and abdominal ultrasound. Follow-up assessments of physical condition and quality of life (QOL) were conducted bi-weekly, with tumor response evaluations monthly, using RECIST v1.0 criteria. While no complete or partial responses were observed, 60% of the dogs maintained stable disease, with a median progression-free survival of 76 days and an overall survival of 90 days. Notably, 60% of the dogs showed clinical benefit through improved QOL and disease stabilization. The treatment was well-tolerated, with only grade I/II toxicities reported. Despite limited biological activity against the cancer, this protocol may enhance QOL in dogs with IMC, offering a valuable palliative option.