Purpose of review
The purpose of this review is to assess recent evidence that demonstrates that aspirin has the potential to be an effective preventive and therapeutic agent in gastrointestinal malignancy.
Long-term follow-up of previous randomized trials of aspirin show that it decreases cancer incidence and mortality with the greatest effects seen on cancers that arise from the gastrointestinal tract. Reduction in distant metastasis and improvements in cancer outcomes appear within 5 years of randomization indicating that aspirin affects tumour growth or the development and spread of metastases from existing cancers or both. In Lynch syndrome (hereditary nonpolyposis colon cancer), aspirin reduces cancer incidence and should be considered standard care. Mutations in the PIK3CA gene may be a potential predictive marker of response to aspirin after a cancer diagnosis, though pharmacological considerations suggest that platelets may be central to the antitumour efficacy of aspirin.
These findings have re-awakened interest in the role of aspirin in the primary prevention of cancer and in the treatment of cancer. Randomized controlled trials are underway to assess the role of aspirin within the treatment algorithms of several solid common cancers.