Artefactual "in-vitro coagulopathy" in a patient with non-Hodgkin lymphoma and lower gastrointestinal bleeding

An 80-year-old man presented in August 2012 with lower gastrointestinal bleeding 3 days after a routine colonoscopy and polypectomy as a day procedure. Five sessile polyps had been excised from the right colon (one from the caecum, one from the hepatic flexure and three from the transverse colon); the largest polyp measured 8 mm. Additionally, a 20 mm sessile polyp was excised from the rectum by means of chromogel elevation and endoscopic mucosal resection. A resultant defect in the muscularis propria was closed with five endoclips. The patient was discharged in the evening, well after the procedure. Subsequent histopathological examination showed that the polyps were tubular or tubulovillous adenomas without dysplasia.