Tolerability of Gemcitabine and Carboplatin Doublet Therapy in Cats with Carcinomas

Abstract

Background: This study was performed to determine the toxicity of gemcitabine‐carboplatin doublet therapy in cats with carcinomas. Hypothesis: Gemcitabine and carboplatin are safe in tumor‐bearing cats. Animals: Twenty cats with spontaneously occurring carcinomas. Methods: A cohort of 6 cats received gemcitabine (2 mg/kg IV) on days 1, 8, and 15 and carboplatin (10 mg/kg IV) immediately after gemcitabine on day 1 of a 21‐day cycle. A 2nd cohort of 14 cats received carboplatin 4 hours after gemcitabine on day 1 and gemcitabine on day 8 but not day 15. The cycles were repeated every 21 days. Results: Cats in the 1st cohort received a median of 3.75 cycles per animal (range, 1–6). Two cats (33.3%) developed grade 3 or 4 neutropenia, 1 (16.7%) grade 4 thrombocytopenia, and 1 (16.7%) grade 3 gastrointestinal toxicity. Gemcitabine dose reductions and treatment delays occurred in 1 and 4 cats, respectively. Cats in the 2nd cohort received a median of 2 cycles per animal (range, 0.5–10). Two cats (14.3%) had grade 3 or 4 neutropenia and 1 (7.1%) had grade 3 and 4 gastrointestinal toxicity. One cat required gemcitabine dose reduction and 6 had treatment delays. In the 2nd cohort, of 11 cats with measurable tumors, there was 1 complete response (pancreatic carcinoma) and 1 partial response (squamous cell carcinoma, receiving concurrent nonsteroidal anti‐inflammatory drugs). Conclusions and Clinical Importance: Gemcitabine‐carboplatin combination appears moderately well tolerated in tumor‐bearing cats. Minimal patient benefit suggests that alternative schedules or combinations of gemcitabine with other agents should be explored.

Comparison of two different doses of bleomycin in electrochemotherapy protocols for feline cutaneous squamous cell carcinoma nonsegregated from ultraviolet light exposure

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Feline exocrine pancreatic carcinoma: a retrospective study of 34 cases

“…Feline pancreatic exocrine carcinomas are uncommon tumours associated with a high metastatic rate and a poor prognosis . The author is aware of only one cat prior to this study that had been documented to live longer than 1 year from time of diagnosis of this disease . The median progression‐free interval was 37 days in this case study and none of the categorical data compared was statistically significant.…”

Chyloabdomen in a cat with pancreatic carcinoma

“…Chemotherapy provided an improvement of quality of life, but survival time remained poor, with a median of 165 days (Linderman et al, 2013). Only four cats were reported to live longer than a year after diagnosis; all of them received gemcitabine-based chemotherapy (Martinez-Ruzafa et al, 2009;Linderman et al, 2013). In our case, chemotherapy was declined, due to poor long-term prognosis.…”

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