Assessment of Efficacy and Toxicity of Cyclophosphamide Chemotherapy in Canines with Malignant Mammary Tumor: A Retrospective Study

Surgical excision with chemotherapy is a commonly used treatment modality to treat canine mammary tumor (CMT), but it is unclear whether different treatment modalities may have similar efficacies and toxicities. The objective of this clinical study was to evaluate the efficacy and toxicity of cyclophosphamide chemotherapy along with surgical excision of malignant mammary tumor in canines by clinical, haemato-biochemical, radiographical, and histopathological evaluation before and after treatment. Eighteen dogs with malignant mammary tumor, reported to Teaching Veterinary Hospital, were divided into two groups consisting of nine dogs in each group. Group I (n = 9) dogs were treated with surgical excision of malignant mammary tumor alone, and group II (n = 9) was treated with surgical excision of mammary tumor with cyclophosphamide chemotherapy at 50–100 mg/m(2) intravenously in weekly doses by three consecutive weeks. In group II, 7 dogs (78%) showed complete regression of tumor after the third dose of cyclophosphamide and showed increase in the quality and survival life and remaining two dogs showed recurrence of tumor after one year. Some dogs showed common adverse reactions such as lethargy, moderate alopecia, vomiting, anorexia, anemia, and haematuria after the third dose of chemotherapy. To conclude, surgical excision combined with cyclophosphamide chemotherapy is an effective protocol for management of malignant mammary tumor in canines with minimal toxicity and it could be possible to increase the quality and survival life of patients.