A Retrospective Study of Chemotherapy-Related Extravasation Events in Dogs and Cats

BACKGROUND: Chemotherapy extravasation is a potentially serious complication. There is a paucity of information in the veterinary literature investigating extravasation events, treatments, and outcomes. OBJECTIVE: Evaluate chemotherapy extravasation events and treatments in dogs and cats, adverse events (AEs), and overall outcomes. ANIMALS: Twenty dogs and three cats were included. METHODS: Retrospective, multicenter, descriptive study including dogs or cats with suspected extravasation from chemotherapy. Information obtained included: signalment, extravasation details and treatment provided, AEs graded according to VCOG-CTCAE v2 criteria, and outcome. RESULTS: The most common drug extravasated was doxorubicin, followed by carboplatin. Carboplatin extravasation (n = 5) resulted in Grades III-IV AEs, all of which required surgical debridement. Doxorubicin extravasation (n = 9) resulted in Grades 0-V AEs, two of which amputation was ultimately recommended, and one of those two was euthanized instead. Extravasation of vinca alkaloids (n = 5) and rabacfosadine (n = 1) resulted in Grades II-III AEs, all managed in the outpatient setting. Mitoxantrone (n = 2) and dacarbazine (n = 1) extravasation resulted in no clinical signs associated with extravasation injury. Seventy-eight percent (18/23) cases had extravasation occur during one of the first four treatments of chemotherapy, with 30% (7/23) occurring during the first chemotherapy treatment. CONCLUSIONS AND CLINICAL IMPORTANCE: Most cases (20/23) had mild to moderate or no AEs. Findings support that carboplatin should be considered a vesicant.