Risk stratification for colorectal cancer in individuals with subtypes of serrated polyps.

OBJECTIVE: The longitudinal risk of colorectal cancer (CRC) associated with subtypes of serrated polyps (SPs) remains incompletely understood. DESIGN: This community-based, case-control study included 317 178 Kaiser Permanente Northern California members who underwent their first colonoscopy during 2006-2016. Nested within this population, we identified 695 cases of CRC and 3475 CRC-free controls (matched 5:1 to cases for age, sex and year of colonoscopy). Two expert pathologists reviewed the tissue slides of all SPs identified on the first colonoscopy and reclassified them to sessile serrated lesions (SSLs), hyperplastic polyps (HPs) and traditional serrated adenomas. SPs with borderline characteristics of SSLs but insufficient to make a definitive diagnosis were categorised as unspecified SPs. The association with development of CRC was assessed using multivariable logistic regression. RESULTS: Compared with individuals with no polyp, the adjusted ORs (aORs) for SSL alone or with synchronous adenoma were 2.9 (95% CI: 1.8 to 4.8) and 4.4 (95% CI: 2.7 to 7.2), respectively. The aORs for SSL with dysplasia, large proximal SSL,and small proximal SSL were 10.3 (95% CI: 2.1 to 50.3), 12.8 (95% CI: 3.5 to 46.9) and 1.9 (95% CI: 0.8 to 4.7), respectively. Proximal unspecified SP also conferred an increased risk (aOR: 5.8, 95% CI: 2.2 to 15.2). Women with SSL were associated with higher risk (aOR: 4.4; 95% CI: 2.3 to 8.2) than men (aOR: 1.7; 95% CI: 0.8 to 3.8). CONCLUSION: Increased risk of CRC was observed in individuals with SSLs, particularly large proximal ones or with dysplasia, supporting close endoscopic surveillance. Proximal unspecified SPs were also associated with increased risk of CRC and should be managed as SSLs.

Increased Risk of Colorectal Cancer in Individuals With a History of Serrated Polyps.

BACKGROUND AND AIMS: Serrated polyp (SPs) are precursors to 20% to 30% of cases of colorectal tumors, but patients' long-term risk after removal of SPs is poorly understood. We investigated the risk of colorectal cancer (CRC) in individuals with a history of SPs. METHODS: We performed a retrospective cohort study of Kaiser Permanente Northern California members who underwent colonoscopy from 2006 through 2016. Study participants were categorized based on the size and location of SPs. We used Cox proportional hazards modeling to estimate the hazard ratio (HR) and 95% confidence interval (CI) for the association of CRC diagnosed more than 1 year after colonoscopy, with polyp type vs no polyp after adjustment for year of colonoscopy, age, sex, race/ethnicity, and smoking history. RESULTS: The study included 233,393 individuals, of whom 445 developed incident CRC. At 10 years, the cumulative incidence rates of CRC for individuals with no polyp, proximal small SPs, proximal large SPs, and distal SPs were 4.7 (95% CI, 4.0-5.6), 14.8 (95% CI, 9.0-24.3), 30.2 (95% CI, 13.2-68.4), and 5.9 (95% CI, 3.6-9.5) per 1000 persons, respectively. In patients with SPs, risk of CRC was not increased until 3 years or more after the first colonoscopy (HR for small proximal SPs 2.6; 95% CI, 1.7-3.9 and HR for large proximal SPs 8.0; 95% CI, 3.6-16.1). The presence of synchronous adenomas increased the risk for CRC (HR for proximal SPs with synchronous adenomas 4.0; 95% CI, 3.0-5.5 and HR for distal SPs with synchronous adenomas 2.4; 95% CI, 1.7-3.4). CONCLUSIONS: In a retrospective analysis of a large cohort of individuals examined by colonoscopy, we found that risk of incident CRC increased in individuals with proximal SPs (large SPs in particular) 3 years or more after the colonoscopy. These findings support guidelines that recommend surveillance colonoscopy for individuals with SPs.

Prognostic criteria for squamous cell cancer of the skin.

BACKGROUND: Non-well-differentiated cutaneous squamous cell carcinomas may display a more aggressive behavior. It is important to better define prognostic criteria for these tumors. METHODS: This was a retrospective case-control analysis of a squamous cell carcinoma database. Patients with non-well-differentiated and well-differentiated tumors were matched based on site of tumor, age, and immunocompromised status. Comparisons included demographics, histology, immunohistochemical protein expressions (Ki-67, p53, E-cadherin, cyclin D1), and clinical outcomes. RESULTS: Demographic features were similar between cases (n=30) and controls (n=30). Non-well-differentiated tumors were larger (1.8 cm versus 1.3 cm, P=0.08), deeper (0.81 cm versus 0.32 cm, P<0.0001), and had greater recurrence (P=0.003). Non-well-differentiated tumors showed increased proliferation rate, Ki-67 index (77% versus 61%, P=0.001); no significant difference in activity of p53, E-cadherin, and cyclin D1 between the two groups. CONCLUSIONS: Tumor differentiation and depth are important pathologic and prognostic criteria for cutaneous squamous cell carcinoma. Immunohistochemistry helps describe patterns of biomarker protein expression and may exemplify aggressive subtypes.