The Role of Aspirin as Antitumoral Agent for Heavily Pretreated Patients With Metastatic Colorectal Cancer Receiving Capecitabine Monotherapy

Background: The potential clinical impact of aspirin use beyond its canonical indications is a novel matter of scientific debate. In patients with metastatic colorectal cancer failing all available options, regorafenib and TAS 102 represent the only chance of treatment. Although effective, these therapeutic options bring along a not-negligible burden in terms of economic costs and toxicity. In this setting, the indication to use aspirin in combination with chemotherapy would potentially represent a medical revolution under the economic and toxicity profile. Patients and Methods: We assessed the role of aspirin in patients with metastatic colorectal cancer who failed all previous treatments and were receiving capecitabine as a salvage option before the introduction of regorafenib and TAS-102. Results: Sixty-six patients were eligible. Twenty patients (30%) were on incidental treatment with aspirin for cardiovascular diseases. Twelve (60%) partial responses were seen in patients on treatment with aspirin, compared with 3 (6%) partial responses in the remaining patients (P = .00007). Sixteen patients on aspirin (80%) obtained disease control versus 14 (30%) patients who were not on aspirin (P = .000377). The median progression-free survival for patients receiving treatment with aspirin was 6.5 months versus 3.3 months for patients who were not on aspirin (hazard ratio, 0.48; 95% confidence interval, 0.30-0.79; . P = .0042). A significantly improved overall survival was also evident in aspirin users (median overall survival, 14.7 vs. 8.7 months, respectively; hazard ratio, 0.43; 95% confidence interval, 0.26-0.72; . P = .0023). Conclusion: Aspirin may improve the clinical outcome of heavily pre-treated patients with metastatic colorectal cancer receiving chemotherapy. Further studies are necessary before application in the clinical practice.