Sessile Serrated Adenomas: High-Risk Adenomas?
SN Salaria, CA Iacobuzio-Donahue, E Montgomery. Johns Hopkins Hospital, Baltimore, MD
Background: Although sessile serrated adenomas (SSAs) were largely unrecognized in general pathology and gastroenterology practice until about 2005, we have diagnosed them since late 2001, allowing up to 8 years of follow-up on such patients. Evidence supports the recognition of SSAs as precursors to some sporadic colorectal carcinomas. It has been proposed that patients with SSA undergo surveillance similar to that for patients with tubular adenomas (TAs). We evaluated the follow up that patients with SSA diagnosed between 2002 and 2004 received in our large teaching institution and compared it to follow-up of randomly selected TAs.
Design: Slides and records of patients diagnosed with SSA from 01/01/2002 to 12/31/2004 from a large hospital were reviewed. A control group of patients with sporadic TAs was randomly selected from the same time period.
Results: A total of 94 patients were diagnosed with SSA between 01/01/2002 - 12/31/2004. Their average age was 61.45 years. One patient presented with a left sided adenocarcinoma arising from an SSA. Forty (42.5%) of the patients (22 men, 18 women) had follow-up colonoscopy. The average interval from diagnosis to initial follow up was 2.47 years (range 0.5-6 years). Follow up showed colonic adenocarcinoma in 2/40 (5%) patients. 1/40 (2%) patient had high grade dysplasia in a TA. 21/40 (52%) patients had additional or persistent SSA and 16/40 (40%) patients had TAs. Of the two adenocarcinomas detected in the follow-up period, one was a right sided moderately differentiated carcinoma and the other a left sided mucinous adenocarcinoma. Forty (21 men, 19 women) randomly chosen patients diagnosed with TAs between 01/01/2002 and 12/31/2004 formed the control group. Their average age was 70.37 years. The average time between the original diagnosis and follow up was 2.95 years (range 0.5-6 years). All 40 (100%) patients had follow up colonoscopy. 35/40 (87.5%) patients had TAs on follow up, 3/40 (7%) patients had hyperplastic polyps, and 1/40 (2%) patient diagnosed with a SSA.
Conclusions: Although the follow-up of SSAs from the study period (2002-2004) was less rigorous than that for sporadic TAs (in fact, patients with sporadic TAs were followed more aggressively than suggested by current guidelines), our clinicians were aware of the need for follow-up of SSA and our data support the view that SSAs are preneoplastic or markers for risk of neoplasia. Those with follow-up were managed as per high-risk adenomas; their clinical outcomes supported this. These results suggest that guidelines for following patients with SSAs are warranted.
Monday, March 22, 2010 9:30 AM
Poster Session I Stowell-Orbison/Surgical Pathology/Autopsy Awards Poster Session # 109, Monday Morning