S2288 Unmasking a Hidden Danger: The Antiplatelet Paradox

Abstract

Introduction: Patients on oral anticoagulants and antiplatelets are at risk of bleeding episodes. Lower gastrointestinal bleeding should never be considered a benign event and this should alert providers to the possible risk of an occult malignancy. Studies show an association between these episodes and a new diagnosis of GI malignancies with a 1-year risk of colorectal cancer (CRC) of 8.1% vs 0.5% in patients with and without bleeding, respectively. Data from the RELY trial found that in major GI bleeds, 8.1% were diagnosed with malignancy, of which 80% was CRC. Herein we present two cases of patients with new onset lower GI bleeding after recently starting anticoagulation and antiplatelet therapy who were found with CRC. Case Description/Methods: 83 year-old man with history of hypertension who came to ER due to multiple episodes of painless bright red blood per rectum after starting aspirin and ticagrelor for recent NSTEMI with PCI and placement of 2 stents 2 weeks prior. Labs showed an anemia of 9.6g/dL. Imaging revealed soft tissue fullness at the distal transverse colon suggestive of a mass causing colo-colonic intussusception. Colonoscopy showed an apple core-like lesion occupying approximately 80% of lumen at the distal transverse colon. Biopsies showed a well differentiated adenocarcinoma. 85 year-old man with history of prostate cancer who was recently diagnosed with atrial fibrillation and started on Apixaban. Three days after initiation of Apixaban patient developed dark stools and discomfort in lower abdomen and periumbilical area for which he went to ER where labs showed a drop in hemoglobin of 2 g/dL. Gastroenterology was consulted and colonoscopy revealed an ulcerated and friable non-obstructing mass at the sigmoid colon covering 3/4 of intestinal lumen. Pathology remarkable for a moderately differentiated Adenocarcinoma. Discussion: It is estimated that by 2030, 14 million patients will develop atrial fibrillation and many will require anticoagulant and/or antiplatelet therapy. This underlines the need for earlier screening and endoscopic evaluation of patients with GI bleeding after starting anticoagulation and/or antiplatelet agents. Lower GI bleeding should not be considered a benign outcome of anticoagulation therapy. Once a bleeding episode is reported, clinicians should consider a malignant process as causative agent. A meticulous clinical examination should be performed, including direct visualization and evaluation for a possible underlying malignant process or pathology like CRC.