Frequency of coexistent carcinoma in sessile serrated adenoma/polyps and traditional serrated adenomas removed by endoscopic resection

Background and study aims: Sessile serrated adenoma/polyps (SSA/Ps) have a different potential than traditional adenomatous polyps for developing into malignant colorectal cancer. However, little is known about the coexistent cancer rate. Here, we evaluate the frequency of carcinoma in serrated polyps removed by endoscopic resection (ER).

Patients and methods: This was a retrospective single-center cohort study of consecutive patients with colorectal polyps who underwent ER from March 2003 to October 2014. We determined the frequency of serrated polyps among all resected colorectal polyps and analyzed the clinicopathological findings as well as the frequency and characteristics of coexistent carcinoma in the serrated polyps resected by ER based on pathology reports.

Results: A total of 21,048 polyps from 15,326 patients were identified, including 15,984 traditional adenomatous polyps (75.9 %), 621 SSA/Ps (3.0 %), 136 traditional serrated adenomas (TSAs) (0.6 %), 1,121 hyperplastic polyps (5.3 %), and 3,186 polyps of other types (15.1 %). The clinical and endoscopic findings of SSA/Ps revealed a male predominance (68.6 %), with 61.7 % of the polyps located in the proximal colon. Males accounted for 77.2 % of all patients with TSAs, and 77.2 % of these polyps were located in the distal colon. The mean sizes of the SSA/Ps and TSAs were 8.8 and 10.7 mm, respectively. Among the SSA/Ps, 8 (1.3 %) cases had coexistent carcinoma, and 1 (0.7 %) patient with TSA showed coexistent carcinoma. In the patients with SSA/Ps, female sex and a tumor size ≥ 10 mm were predictive factors for coexistent carcinoma.

Conclusions: The frequency of SSA/Ps with carcinoma was lower than that for traditional adenoma. Female sex and tumor size ≥ 10 mm were significant predictive factors for coexistent carcinoma.

• References

• 1 Jass JR. Serrated route to colorectal cancer: back street or super highway?. J Pathol 2001; 193: 283-285
• 2 Rembacken BJ, Fujii T, Cairns A et al. Flat and depressed colonic neoplasms: a prospective study of 1000 colonoscopies in the UK. Lancet 2000; 355: 1211-1214
• 3 Goldstein NS, Bhanot P, Odish E et al. Hyperplastic-like colon polyps that preceded microsatellite-unstable adenocarcinomas. Am J Clin Pathol 2003; 119: 778-796
• 4 Rex DK, Ahnen DJ, Baron JA et al. Serrated lesions of the colorectum: review and recommendations from an expert panel. Am J Gastroenterol 2012; 107: 1315-1329; quiz 1314, 1330
• 5 Huang CS, Farraye FA, Yang S et al. The clinical significance of serrated polyps. Am J Gastroenterol 2011; 106: 229-240; quiz 241
• 6 Snover DC. Update on the serrated pathway to colorectal carcinoma. Hum Pathol 2011; 42: 1-10
• 7 Schreiner MA, Weiss DG, Lieberman DA. Proximal and large hyperplastic and nondysplastic serrated polyps detected by colonoscopy are associated with neoplasia. Gastroenterology 2010; 139: 1497-1502
• 8 Hiraoka S, Kato J, Fujiki S et al. The presence of large serrated polyps increases risk for colorectal cancer. Gastroenterology 2010; 139: 1503-1510, 1510 e1501 – e1503
• 9 Snover DC, Jass JR, Fenoglio-Preiser C et al. Serrated polyps of the large intestine: a morphologic and molecular review of an evolving concept. Am J Clin Pathol 2005; 124: 380-391
• 10 Mattar W, Rex DK. Large sessile adenomas are associated with a high prevalence of synchronous advanced adenomas. Clin Gastroenterol Hepatol 2008; 6: 877-879
• 11 Salama M, Ormonde D, Quach T et al. Outcomes of endoscopic resection of large colorectal neoplasms: an Australian experience. J Gastroenterol Hepatol 2010; 25: 84-89
• 12 Inoue H, Kashida H, Kudo S et al. The Paris endoscopic classification of superficial neoplastic lesions: esophagus, stomach, and colon: November 30 to December 1, 2002. Gastrointest Endosc 2003; 58: 3-43
• 13 Fujimori Y, Fujimori T, Imura J et al. An assessment of the diagnostic criteria for sessile serrated adenoma/polyps: SSA/Ps using image processing software analysis for Ki67 immunohistochemistry. Diagn Pathol 2012; 7: 59
• 14 Lane N. The precursor tissue of ordinary large bowel cancer. Cancer Res 1976; 36: 2669-2672
• 15 Clark JC, Collan Y, Eide TJ et al. Prevalence of polyps in an autopsy series from areas with varying incidence of large-bowel cancer. Int J Cancer 1985; 36: 179-186
• 16 Correa P, Strong JP, Reif A et al. The epidemiology of colorectal polyps: prevalence in New Orleans and international comparisons. Cancer 1977; 39: 2258-2264
• 17 Williams AR, Balasooriya BA, Day DW. Polyps and cancer of the large bowel: a necropsy study in Liverpool. Gut 1982; 23: 835-842
• 18 Vatn MH, Stalsberg H. The prevalence of polyps of the large intestine in Oslo: an autopsy study. Cancer 1982; 49: 819-825
• 19 Longacre TA, Fenoglio-Preiser CM. Mixed hyperplastic adenomatous polyps/serrated adenomas. A distinct form of colorectal neoplasia. Am J Surg Pathol 1990; 14: 524-537
• 20 Torlakovic E, Snover DC. Serrated adenomatous polyposis in humans. Gastroenterology 1996; 110: 748-755
• 21 Lash RH, Genta RM, Schuler CM. Sessile serrated adenomas: prevalence of dysplasia and carcinoma in 2139 patients. J Clin Pathol 2010; 63: 681-686
• 22 Spring KJ, Zhao ZZ, Karamatic R et al. High prevalence of sessile serrated adenomas with BRAF mutations: a prospective study of patients undergoing colonoscopy. Gastroenterology 2006; 131: 1400-1407
• 23 Carr NJ, Mahajan H, Tan KL et al. Serrated and non-serrated polyps of the colorectum: their prevalence in an unselected case series and correlation of BRAF mutation analysis with the diagnosis of sessile serrated adenoma. J Clin Pathol 2009; 62: 516-518
• 24 Kim KM, Lee EJ, Kim YH et al. KRAS mutations in traditional serrated adenomas from Korea herald an aggressive phenotype. Am J Surg Pathol 2010; 34: 667-675
• 25 Oono Y, Fu K, Nakamura H et al. Progression of a sessile serrated adenoma to an early invasive cancer within 8 months. Dig Dis Sci 2009; 54: 906-909
• 26 Pohl H, Srivastava A, Bensen SP et al. Incomplete polyp resection during colonoscopy-results of the complete adenoma resection (CARE) study. Gastroenterology 2013; 144: 74-80 e71
• 27 Rex KD, Vemulapalli KC, Rex DK. Recurrence rates after EMR of large sessile serrated polyps. Gastrointest Endosc 2015; 8: 538-541