Routine screening for colon cancer after conservative treatment of diverticulitis

It is generally advised to perform colonoscopy after conservatively treated diverticulitis because colon cancer may present itself with similar symptoms, laboratory and radiological results. With this study we investigated in what percentage of patients a malignancy was found by performing routine colonoscopy or radiologic imaging after a conservatively treated episode of diverticulitis, and whether this follow-up programme could be reserved for a selected group of patients.

In our hospital, routine colonoscopy or, as a second choice, radiologic imaging has been standard practice over the last decade. We collected all colonoscopy and radiologic imaging results that were conducted of all 516 patients who were diagnosed with diverticulitis in this period.

Of those 516 patients, 378 had undergone colonoscopy, 45 radiologic imaging and 93 did not undergo any additional investigation. Eight cases of malignant neoplasia were found in those patients (2.1%), and an additional number of 40 adenomatous polyps (9.5%). Six out of 8 patients with colon cancer reported rectal blood loss, significant weight loss or persisting abdominal pain after being treated for diverticulitis.

In patients who were conservatively treated with routine colonoscopy or radiologic imaging for apparent diverticulitis, a malignant tumour was found in the colon in 2.1% of them. If only performed in patients reporting alarm symptoms, a case of colon cancer would be missed in only 0.5% of patients conservatively treated for diverticulitis. Therefore, screening for colon cancer after conservative treatment of diverticulitis is only indicated in symptomatic patients.