Anticoagulants and Gastrointestinal Cancer Detection

Patients with gastrointestinal (GI) cancer frequently present with GI bleeding. GI bleeding (GIB) may be classified based on location: upper (esophagus, stomach or duodenum) versus lower (jejunum, ileum, large intestine). 

Patients with upper GIB may present with hematemesis and melena (dark, tarry stools) while lower GIB patients may present with hematochezia or bright red blood per rectum.

Depending on the stage and type of GI malignancy, the patient may not complain of symptoms and the lesion may not be detected if they are non-compliant or do not qualify for the current screening guidelines.

These patients with previously undetected GI malignancy my inadvertently undergo what has been called an “antigocoagulation GI stress-test” when started on antiplatelets and/or anticoagulants.¹

This could represent a previously under-recognized modality leading to the early detection of a GI malignancy.

Patients with an occult GI malignancy who are otherwise asymptomatic may present with signs and symptoms of GIB when initiated on anticoagulation that would have been previously absent had it not been for a new medication.

Consequently, these patients may require earlier endoscopic investigation to evaluate a potential source of bleeding.

Endoscopic procedures that potentially could be utilized include esophagogastroduodenoscopy (EGD), endoscopic ultrasound (EUS), endoscopic retrograde cholangiopancreatography (ERCP), small bowel enteroscopy, and colonoscopy.

A study conducted by Asiimwe and colleages found that patients receiving warfarin or clopidogrel who experienced a GI bleed were approximately 6 times more likely to be diagnosed with a GI malignancy compared to those without GI bleeding.²

In addition, the increased risk of GI cancer detection was the most prominent within the first 6 months of the first episode of GI bleeding² which correlates previous data showing most GI bleeding occurs within the first year of anticoagulant/antiplatelet initiation.¹