Non-Steroidal Anti-Inflammatory Drugs as Chemopreventive Agents: Evidence from Cancer Treatment in Domestic Animals

Aims: This study aims to systematically review currently available data on the use of non-steroidal anti-inflammatory drugs (NSAIDs) in the treatment of cancer in domestic animals to evaluate the efficacy of different treatment protocols and to suggest further recommendations for future study.

Methodology: Literature data on the use of NSAIDs in domestic animals as chemo-preventive agents in the last decade were collected and critically reviewed. Some older sources from the primary literature search have also been included to determine the background information leading to current rationale behind NSAID use in oncology.

Results: In vitro inhibitions of tumour cell proliferation by both piroxicam and meloxicam have been demonstrated only at higher concentrations than those achievable in vivo. However, remission rates ranging from 7% to 71% have been observed when piroxicam is administered orally, either alone or in conjunction with other anticancer agents for treatment of transitional cell carcinoma of the urinary bladder of dogs. Piroxicam has also had positive results for multicentric lymphoma and nasal tumour, with remission rates of 79% and 75% respectively. In many cases, NSAID treatment showed increased median survival times and an improved quality of life of treated animals.

Conclusion: NSAIDs have shown potential as an adjunctive therapy for the treatment of some cancers in domestic animals. This review highlights the major limitation of current studies on the role of NSAIDs in cancer treatment, including limited sample size in most cases and mainly by retrospective studies. A recommendation for future study is the investigation of multi-institutional animal trials to increase case numbers and allow for better statistical analysis with adequate control groups.