Are NSAIDs Coming Back to Colorectal Cancer Therapy or Not?

© 2014, Springer Science+Business Media New York. Despite adjuvant chemotherapy, between 20 and 50 % of patients with stage II/III colorectal cancer (CRC) will suffer recurrence, usually as incurable metastatic disease. Attempts to improve the efficacy of adjuvant regimens with addition of biologics have failed, and there is therefore a pressing need for novel therapeutic approaches. Inflammatory mediators, including the cyclooxygenase (COX) enzyme family, are commonly upregulated in CRC and known to promote tumour growth in preclinical models. COX inhibition by aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs) may exert an antineoplastic effect. Despite considerable evidence in CRC prevention and emerging data demonstrating that regular aspirin reduces the frequency of metastases following CRC resection, its use has not become widespread due to concerns regarding toxicities. However, the recent identification of biomarkers that may predict aspirin benefit has renewed interest in the field. Large, randomised controlled trials underway/in set-up should provide definitive evidence of the efficacy of aspirin/NSAIDs as adjuvant therapy in CRC. This review examines the field to date, with focus on the biomarkers which may help refine the risk-benefit ratio.