Cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) is the gold-standard first-line chemotherapy protocol for canine multicentric lymphoma, with overall response rates of 80%–95% and median overall survival times of 10–12 months.Journal of Vete…+1

Multiple CHOP protocol durations are in clinical use, and outcomes are comparable across them. The most widely used formats are CHOP-25 (25-week protocol) and CHOP-19 (19-week condensed version); median progression-free survival (PFS) is 209 days with CHOP-25 and 196 days with CHOP-19, and median overall survival (OS) is 321 days and 302 days, respectively — with no statistically significant difference between the two.Journal of Vete… A 15-week maintenance-free protocol produces an overall response rate of 98%, a complete response (CR) rate of 78%, median PFS of 176 days, and median disease-specific OS of 311 days.Veterinary and… A separate evaluation of the 15-week protocol reported a 100% overall response rate and median PFS of 140 days.Veterinary and…

Complete response to induction is a key prognostic milestone. In small-breed dogs treated with CHOP, CR rate is 54.3%, partial response (PR) rate is 31.4%, and no response rate is 14.3%; median survival times are 683 days for CR, 241 days for PR, and 119 days for no-response patients.Animals

Immunophenotype and substage are the most consistently identified prognostic factors. B-cell immunophenotype, substage a (absence of systemic signs), absence of anemia at diagnosis, and achieving CR as best response are each independently associated with longer PFS.Veterinary and… A pretreatment neutrophil-to-lymphocyte ratio below 9.44 and absence of anemia at diagnosis are independently predictive of longer first-remission PFS in centroblastic diffuse large B-cell lymphoma.Veterinary and… Peripheral neutrophilia at diagnosis is an adverse prognostic factor: dogs with neutrophilia treated with CHOP have a median PFS of 70 days versus 184.5 days in dogs without neutrophilia, and overall response rates of 75% versus 97%, respectively.Journal of the…

Dogs that progress early during or after CHOP have substantially worse rescue outcomes. Duration of first remission after CHOP is significantly associated with response rate, PFS, and survival time after rescue chemotherapy.Journal of Vete… When CHOP reinduction is used after relapse following protocol completion, a second CR is achieved in 78% of dogs, with a median second remission duration of 159 days — approximately half the first remission duration.Journal of Vete…

Would you like to review the available rescue protocol options and their response rates for dogs that relapse after first-line CHOP?