Introduction
thrombosis, tumours, cancer, inflammation, VTE, tumour, venous thromboembolism
THROMBOSIS, TUMOURS, CANCER, INFLAMMATION, DISEASE, METASTATIC DISEASE, TUMOUR
Activated platelets play a central role in the development and spread of cancer, as well as in haemostasis and thrombosis, tissue repair, and inflammation [The primary effect of once-daily low-dose (75–100 mg) aspirin is the irreversible acetylation of cyclo-oxygenase-1 (COX-1) in platelets [The link between TXAEpidemiological and randomised data demonstrate that once-daily aspirin use reduces cancer incidence particularly for tumours that arise from the gastrointestinal tract [It is estimated that about 5% of patients who present with unexplained venous thromboembolism (VTE) develop cancer within 1 year of diagnosis. The risk of developing a cancer-associated VTE depends on the type and stage of the cancer, treatment received, as well as the underlying risk of the patient [TXAFurther understanding of the mechanism(s) underlying the anti-cancer effects of aspirin would permit a more nuanced and precision-medicine approach to the use of aspirin in the field of oncology. The ongoing adjuvant Add-Aspirin trial (ISRCTN74358648) which is evaluating the effect of aspirin use after radical treatment in four different tumour types and evaluating 2 different doses of aspirin, provided an opportunity to further study thromboxane biosynthesis in cancer patients at an early stage of their disease, and the short-term effects of two doses aspirin. The specific aims of this study were: (i) to examine the levels of thromboxane biosynthesis using U-TXM as a biomarker in cancer patients who had recently completed radical treatment and had no radiological or standard clinical evidence of metastatic disease, (ii) to evaluate the effects of aspirin 100 and 300 mg daily on U-TXM in this cohort and (iii) to provide information about participant treatment compliance in this blinded placebo-controlled trial particularly as aspirin is also available as an over-the-counter preparation.