High microsatellite instability (MSI-H) allows the identification of a subset of colorectal carcinomas associated with good prognosis and a higher incidence of Lynch syndrome. The aim of this work was to assess the interobserver variability and optimize our MSI-H prediction model previously published based on phenotypic features.The validation series collected from five different hospitals included 265 primary colorectal carcinomas from the same number of patients. The eight clinicopathological parameters that integrate our original model were evaluated in the corresponding centers. Homogeneity assessment revealed significant differences between hospitals in the estimation of the growth pattern, presence of Crohn-like reaction, percentage of cribriform structures, and Ki-67 positivity. Despite this observation, our model was globally able to predict MSI-H with a negative predictive value of 97.0%. The optimization studies were carried out with 615 cases and resulted in a new prediction model RERtest8, which includes the presence of tumor infiltrating lymphocytes at the expense of the percentage of cribriform structures. This refined model achieves a negative predictive value of 97.9% that is maintained even when the immunohistochemical parameters are left out, RERtest6. The high negative predictive value achieved by our models allows the reduction of the cases to be tested for MSI to less than 10%. Furthermore, the easy evaluation of the parameters included in the model renders it a useful tool for the routine practice and can reinforce other published models and the current clinical protocols to detect the subset of colorectal cancer patients bearing hereditary nonpolyposis colorectal cancers risk and/or MSI-H phenotype.

BackgroundPoor attendance to cervical cancer (CC) screening is a major risk factor for CC. Efforts to capture underscreened women are considerable and once women agree to participate, the provision of longitudinal validity of the screening test is of paramount relevance. We evaluate the addition of high risk HPV test (HPV) to cervical cytology as a primary screening test among underscreened women in the longitudinal prediction of intraepithelial lesions grade 2 or worse (CIN2+).MethodsWomen were included in the study if they were older than 39 years and with no evidence of cervical cytology in the previous five years within the Public Primary Health Care System in Catalonia (Spain). 1,832 underscreened women from eight public primary health areas were identified during 2007–2008 and followed-up for over three years to estimate longitudinal detection of CIN2+. Accuracy of each screening test and the combination of both to detect CIN2+ was estimated. The risk of developing CIN2+ lesions according to histology data by cytology and HPV test results at baseline was estimated using the Kaplan–Meier method.ResultsAt baseline, 6.7% of participants were HPV positive, 2.2% had an abnormal cytology and 1.3% had both tests positive. At the end of follow-up, 18 out of 767 (2.3%) underscreened women had a CIN2+, two of which were invasive CC. The three-year longitudinal sensitivity and specificity estimates to detect CIN2+ were 90.5% and 93.0% for HPV test and 38.2% and 97.8% for cytology. The negative predictive value was >99.0% for each test. No additional gains in validity parameters of HPV test were observed when adding cytology as co-test. The referral to colposcopy was higher for HPV but generated 53% higher detection of CIN2+ compared to cytology.ConclusionsUnderscreened women had high burden of cervical disease. Primary HPV screening followed by cytology triage could be the optimal strategy to identify CIN2+ leading to longer and safe screen intervals.

Objective. Audit of women with invasive cervical cancer (CC) is critical for quality control within screening activities. We analysed the screening history in the 10 years preceding the study entry in women with and without CC during 2000–2011. Methods. 323 women with CC from six pathology departments in Catalonia (Spain) and 23,782 women with negative cytology were compared. Age, previous history of cytologies, and histological type and FIGO stage were collected from the pathology registries. Logistic regression analysis was used to estimate odds ratios (OR) and 95% confidence intervals (CI95%). Results. History of cytology was registered in 26.2% of CC cases and in 78% of the control women (P < 0.0001) and its frequency decreased with increasing age. Compared to women with squamous cell carcinoma, adenocarcinoma cases were significantly more likely to have a cytology within the 3-year interval preceding cancer diagnosis (OR = 2.6 CI 95%: 1.2–5.6) and to have normal cytology results in previous screenings (OR = 2.4 CI 95%: 1.2–4.5). FIGO II–IV cases were more common among older women (older than 60 years). Conclusions. Absence of prior screening history was extremely common among CC cases compared to controls. Organized actions to reduce underscreened women and use of highly sensitive HPV-based tests could be important to reduce CC burden.

BackgroundA protocol for cervical cancer screening among sexually active women 25 to 65 years of age was introduced in 2006 in Catalonia, Spain to increase coverage and to recommend a 3-year-interval between screening cytology. In addition, Human Papillomavirus (HPV) was offered as a triage test for women with a diagnosis of atypical squamous cells of undetermined significance (ASC-US). HPV testing was recommended within 3 months of ASC-US diagnosis. According to protocol, HPV negative women were referred to regular screening including a cytological exam every 3 years while HPV positive women were referred to colposcopy and closer follow-up. We evaluated the implementation of the protocol and the prediction of HPV testing as a triage tool for cervical intraepithelial lesions grade two or worse (CIN2+) in women with a cytological diagnosis of ASC-US.MethodsDuring 2007-08 a total of 611 women from five reference laboratories in Catalonia with a novel diagnosis of ASC-US were referred for high risk HPV (hrHPV) triage using high risk Hybrid Capture version 2. Using routine record linkage data, women were followed for 3 years to evaluate hrHPV testing efficacy for predicting CIN2+ cases. Logistic regression analysis was used to estimate the odds ratio for CIN2 +.ResultsAmong the 611 women diagnosed with ASC-US, 493 (80.7%) had at least one follow-up visit during the study period. hrHPV was detected in 48.3% of the women at study entry (mean age 35.2 years). hrHPV positivity decreased with increasing age from 72.6% among women younger than 25 years to 31.6% in women older than 54 years (p < 0.01).At the end of the 3 years follow-up period, 37 women with a diagnosis of CIN2+ (18 CIN2, 16 CIN3, 2 cancers, and 1 with high squamous intraepithelial lesions -HSIL) were identified and all but one had a hrHPV positive test at study entry. Sensitivity to detect CIN2+ of hrHPV was 97.2% (95%confidence interval (CI) = 85.5-99.9) and specificity was 68.3% (95%CI = 63.1-73.2). The odds ratio for CIN2+ was 45.3 (95% CI: 6.2-333.0), when among ASC-US hrHPV positive women were compared to ASC-US hrHPV negative women.ConclusionsTriage of ASC-US with hrHPV testing showed a high sensitivity for the detection of CIN2+ and a high negative predictive value after 3 years of follow-up. The results of this study are in line with the current guidelines for triage of women with ASC-US in the target age range of 25-65. Non adherence to guidelines will lead to unnecessary medical interventions. Further investigation is needed to improve specificity of ASC-US triage.

In the last four years, Genome-Wide Association Studies (GWAS) have identified sixteen low-penetrance polymorphisms on fourteen different loci associated with colorectal cancer (CRC). Due to the low risks conferred by known common variants, most of the 35% broad-sense heritability estimated by twin studies remains unexplained. Recently our group performed a case-control study for eight Single Nucleotide Polymorphisms (SNPs) in 4 CRC genes. The present investigation is a follow-up of that study. We have genotyped six SNPs that showed a positive association and carried out a meta-analysis based on eight additional studies comprising in total more than 8000 cases and 6000 controls. The estimated recessive odds ratio for one of the SNPs, rs3219489 (MUTYH Q338H), decreased from 1.52 in the original Swedish study, to 1.18 in the Swedish replication, and to 1.08 in the initial meta-analysis. Since the corresponding summary probability value was 0.06, we decided to retrieve additional information for this polymorphism. The incorporation of six further studies resulted in around 13000 cases and 13000 controls. The newly updated OR was 1.03. The results from the present large, multicenter study illustrate the possibility of decreasing effect sizes with increasing samples sizes. Phenotypic heterogeneity, differential environmental exposures, and population specific linkage disequilibrium patterns may explain the observed difference of genetic effects between Sweden and the other investigated cohorts.