S0292 Impact of Antithrombotic Therapy (ATT) on Screening of Colorectal Cancer in Ecuador

Abstract

INTRODUCTION: The majority of colorectal cancer (CRC) patients present with bleeding-related symptoms. The frequency of the administration of antithrombotic drugs has been increasing. Antithrombotic therapy (ATT) may induce bleeding from colorectal cancer (CRC) and may facilitate early detection of CRC. We aimed to determine the impact of ATT on diagnosis of CRC. METHODS: We retrospectively studied the patients who pathologically diagnosed CRC in our country between July 2015 to February 2020. Bleeding related symptoms and TNM-stage were compared between patients with CRC receiving antiplatelet therapy, anticoagulant therapy, multi-ATT (e.g., dual antiplatelet drug or antiplatelet drugs plus anticoagulant drugs), and non-ATT. Bleeding related symptoms were defined as overt bleeding (hematochezia, melena, and rectal bleeding), positive fecal blood test and anemia. RESULTS: A total of 1114 patients with CRC were analyzed. Of these, 218 patients were included in antiplatelet therapy group, 109 patients in anticoagulant therapy group, 101 patients in multi-ATT and 686 patients in non-ATT group. With regard to reasons for work up of CRC, the rate of bleeding related symptoms in antiplatelet therapy group (54%, P = 0.038), antithrombotic therapy group (62%, P = 0.001) and multi-ATT group (66%, P < 0.001) were significantly higher than those in non-ATT group (47%). Anticoagulant therapy (58%, OR, 1.643; 95% CI, 1.126–2.397; P = 0.01) and Multi-ATT (57%, OR 1.586; 95% CI 1.089–2.309; P = 0.012) were significantly associated with early stage diagnosis of CRC compared with non-ATT (46%), but antiplatelet therapy (50%, OR, 1.171; 95% CI 0.900–1.522; P = 0.34) was not. CONCLUSION: Anticoagulant therapy and multi-ATT may facilitate detection of CRC in its early stage through bleeding related symptoms.