Hematological toxicity of doxorubicin-containing protocols in dogs with spontaneously occurring malignant tumors

The medical records of 49 dogs with spontaneously occurring malignant tumor s treated with doxorubicin-based chemotherapy protocols were evaluated for hematological toxicity. Protocols included vincristine, doxorubicin, and cy clophosphamide (VAC); 5-fluorouracil, doxorubicin, and cyclophosphamide (FA C); doxorubicin and cyclophosphamide (AC); and doxorubicin and dacarbazine (ADIC). Prevalence of Grades 1, 2, or 3 toxicities were less than 30%, and the prevalence of Grade 4 toxicity alone was less than 5%, The frequency of sepsis was less than 2.5% in dogs treated with VAC, FAG, or AC, and it was 15% in dogs treated with ADIC. There were no significant differences in th e prevalence or severity of hematological toxicity caused by VAC or AC. Fiv e-fluorouracil, doxorubicin, and cyclophosphamide caused significantly more severe neutropenia than VAC or AC. The low prevalence of hematological com plications makes these protocols acceptable for use in practice.