Clinicopathological Features of Sessile Serrated Polyp/Adenoma: Improving Serration Detection to Adjust Interval Follow-up Colonoscopy

Abstract

Introduction: The majority of colorectal cancers (CRCs) develop through the adenoma-carcinoma sequence, while 15-20% develop via the serrated neoplasia pathway. Sessile Serrated Adenoma/Polyp (SSA/P) is more difficult to detect during colonoscopy, leading to a disproportionate contribution to interval carcinoma (CRCs diagnosed within 6-36 months of colonoscopy). These polyps lead to cancer faster than conventional adenomas. In order to better define patients at risk for these lesions, we performed a retrospective study to evaluate clinicopathological features of patients diagnosed with SSA/P. Methods: We reviewed the pathology reports of patients at Howard University Hospital from 2010-2015. We identified 5,900 patients with polyps, of whom 312 (5.3%) were diagnosed with SSA/P. We presented the frequency of gender, age groups, anatomic location, clinical symptoms and reason for colonoscopy in SSA/P patients. Results: We identified 312 cases with SSA/P. The incidence of SSA/P over that 5-year period was 5.3%. 198/312 (63.4%) patients had 2 or more polyps. 54.5% of the patients diagnosed with SSA/P were females. 70.5% of patients were 50-64 years of age and 18% were older than 65. SSA/P lesions' locations were as follows: rectal -32.1%; rectosigmoid -18.6%; sigmoid - 16.8%; Ascending Colon - 13.2 %; Descending Colon - 7.1%. Reasons for colonoscopy were as follows: Screening - 43.6 %; GI bleeding - 15.1%; Abdominal Pain - 13.1%; Change in Bowel Habits - 10.2%. Conclusion: Our results show that there is a slightly increased predominance of SSA/P occurrence in females. The most common age range for an SSA/P diagnosis is from 50 to 64 years. This age range is younger in comparison to patients with conventional adenomas. We also found that SSA/P was predominantly distal (rectal, rectosigmoid, sigmoid) whereas previous literature reports a proximal location for SSA/P. Most patients in our study were diagnosed in screening colonoscopies; however, other patients presented with symptoms such as GI bleeding, abdominal pain, or change in bowel habits.Figure 1Figure 2Figure 3