Outcome of treatment with a 10-week COP protocol in cats with intermediate or large cell lymphoma: 27 cases...

The aim of this retrospective clinical study was to evaluate and report response to treatment with a 10-week maintenance-free COP (COP-10) protocol in a cohort of 27 cats with intermediate or large cell lymphoma. Additionally, to identify any potential prognostic factors for predicting the treatment response.

The medical records of cats diagnosed with intermediate or large cell lymphoma in a single institution in the period 2014 to 2023 and treated with COP-10 as first-line treatment were reviewed.

Twenty-seven cats were included in the study. The median age was 10 years, 67% of the cats were in stages I to II and the most common anatomical location was alimentary (37%). The overall response rate was 65%, with 38% of cats achieving complete remission and 27% partial remission. For cats achieving complete remission, the median progression-free interval and the median lymphoma-specific survival time were both 1,139 days. For cats in partial remission, the median progression-free interval and the median lymphoma-specific survival time were 53 and 210 days, respectively. Clinical stage was significantly related to treatment response and survival time.

Treatment with the short protocol COP-10 resulted in remission rates and durable first remissions for cats achieving complete remission comparable to responses seen with longer-duration chemotherapy protocols. The results from this study may impact economic and logistic decisions for owners, as well as the quality of life for patients in the future.