Background: American College of Gastroenterology guidelines recommend colonoscopy as follow-up after an episode of diverticulitis, as there has been some association between diverticulitis and the diagnosis of colon cancer. There is limited data on the yield of this procedure in this setting. Recent studies have suggested that colonoscopy may only be warranted after episodes of complicated diverticulitis involving CT-proven abscess or reactive lymph nodes, which are associated with a higher likelihood of the presence of occult colon cancer.
Objective: The primary objective is to retrospectively examine the results of colonoscopy done for follow-up of diverticulitis at our center, specifically looking for newly diagnosed carcinoma of the colon. We will compare the findings between unique sup-groups based on previous screening status and family history. This study may help to develop future guidelines for follow-up of diverticulitis.
Method: A search was performed in the electronic medical record for adult patients with colonoscopy performed for indication “diverticulitis” or “abnormal abdominal CT scan” in the past five years. Of 521 charts screened, 136 with CT-diagnosed diverticulitis and sufficient documentation were included in the study. Data regarding demographics, medical history, imaging, colonoscopy findings, and pathology was reviewed. A descriptive analysis was performed and patient sub-groups were compared using Fisher’s exact test.
Results: Of 136 patients with diverticulitis, two had adenocarcinoma of the sigmoid colon diagnosed after follow-up colonoscopy (1.5%). Both carcinomas were diagnosed after first episodes of uncomplicated diverticulitis, and neither in this group had previous colonoscopies. Both localized to the same spot as the diverticulitis by CT. One of the carcinomas was found in a patient under 50 years old who had a reported family history of colon cancer. The second carcinoma was diagnosed in a patient over 50 years old, and this patient had no family history. There was also one neuroendocrine tumor of the rectum incidentally found. There was no significant difference between rates of carcinoma diagnosed among subgroups examined (family history vs. no family history, previous screening colonoscopy vs. never screened, uncomplicated vs. complicated diverticulitis, and age over 50 vs. under 50).
Conclusion: Based on these findings, we believe colonoscopy should still be pursued as follow-up after any episode of diverticulitis to rule out occult colon cancer. More evidence and a larger sample size will be needed before recommending changes to the current guidelines
