49 research outputs found
Dysplasia in Barrett esophagus
BACKGROUND Dysplasia in Barrett esophagus is a premalignant condition that is associated with an increased risk of developing esophageal adenocarcinoma. Unfortunately, clinical investigation aimed at prevention of progression to malignant disease has been hampered by the variable prevalence of dysplasia reported in the literature. The objective of the current study was to more accurately determine the prevalence of dysplasia among individuals with Barrett esophagus who would be available for enrollment in a chemoprevention trial. METHODS The pathology archives of 3 institutions were reviewed over a 5-year period for all reports of diagnoses of Barrett esophagus. Surgical cases, malignancies, and duplicate or referral cases were excluded from the analysis. RESULTS A total of 790 cases of Barrett esophagus were identified. Of these, 37 (4.7%) were cases of low-grade dysplasia (LGD), and 20 (2.5%) were cases of high-grade dysplasia. The University of Michigan Medical Center (Ann Arbor, MI) diagnosed 18 cases of LGD, Henry Ford Hospital (Detroit, MI) diagnosed 15 cases of LGD, and Brigham and Women's Hospital (Boston, MA) diagnosed 4 cases of LGD in patients with Barrett esophagus over the 5-year study period. CONCLUSIONS The confirmed low prevalence of cases of LGD will affect the design of future clinical trials of chemopreventive interventions for Barrett esophagus. Cancer 2004. © 2004 American Cancer Society.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/34387/1/20149_ftp.pd
Microsatellite Instability and DNA Mismatch Repair Protein Deficiency in Lynch Syndrome Colorectal Polyps
Colorectal cancers associated with Lynch syndrome (LS) are characterized by deficient DNA mismatch repair (MMR) function. Our aim was to evaluate the prevalence of microsatellite instability (MSI) and loss of MMR protein expression in LS-associated polyps. Sixty two colorectal polyps – 37 adenomas (APs), 23 hyperplastic polyps (HPs), and 2 sessile serrated polyps (SSPs) – from 34 subjects with germline MMR gene mutations were tested for MSI using a single pentaplex PCR for five mononucleotide repeat microsatellite markers, and also for expression of MLH1, MSH2, MSH6, and PMS2 proteins by immunohistochemistry (IHC). High-level MSI (MSI-H) was seen in 15/37 (41%) APs, 1/23 (4%) HPs, and 1/2 (50%) SSPs. Loss of MMR protein expression was seen in 18/36 (50%) APs, 0/21 HPs, and 0/2 SSPs. APs ≥8 mm were significantly more likely to demonstrate MSI-H (OR = 9.98, 95% CI: 1.52-65.65, p = 0.02) and deficient MMR protein expression (OR = 3.17, 95% CI: 1.20-8.37, p = 0.02) compared with those <8 mm. All (6/6) APs ≥10 mm demonstrated both MSI-H and loss of MMR protein expression by IHC. Our finding that the prevalence of MMR deficiency increases with the size of APs suggests that loss of MMR function is a late event in LS-associated colorectal neoplasia. Although testing large APs may be of value in the diagnostic evaluation of patients with suspected LS, the absence of an MMR deficient phenotype in an adenoma cannot be considered strong evidence against LS, as it is with colorectal carcinomas
Surveillance for pancreatic cancer in high-risk individuals
Background: Surveillance of individuals at high risk of pancreatic ductal adenocarcinoma (PDAC) and its
precursors might lead to better outcomes. The aim of this study was to determine the prevalence
and outcomes of PDAC and high-risk neoplastic precursor lesions among such patients participating
in surveillance programmes.
Methods: A multicentre study was conducted through the International CAncer of the Pancreas Screening (CAPS) Consortium Registry to identify high-risk individuals who had undergone pancreatic resection or progressed to advanced PDAC while under surveillance. High-risk neoplastic precursor lesions
were defined as: pancreatic intraepithelial neoplasia (PanIN) 3, intraductal papillary mucinous neoplasia
(IPMN) with high-grade dysplasia, and pancreatic neuroendocrine tumours at least 2 cm in diameter.
Results: Of 76 high-risk individuals identified in 11 surveillance programmes, 71 had undergone surgery
and five had been diagnosed with inoperable PDAC. Of the 71 patients who underwent resection, 32
(45 per cent) had PDAC or a high-risk precursor (19 PDAC, 4 main-duct IPMN, 4 branch-duct IPMN,
5 PanIN-3); the other 39 patients had lesions thought to be associated with a lower risk of neoplastic
progression. Age at least 65 years, female sex, carriage of a gene mutation and location of a lesion in the
head/uncinate region were associated with high-risk precursor lesions or PDAC. The survival of high-risk
individuals with low-risk neoplastic lesions did not differ from that in those with high-risk precursor
lesions. Survival was worse among patients with PDAC. There was no surgery-related mortality.
Conclusion: A high proportion of high-risk individuals who had surgical resection for screening- or
surveillance-detected pancreatic lesions had a high-risk neoplastic precursor lesion or PDAC
Delphi Initiative for Early-Onset Colorectal Cancer (DIRECt) International Management Guidelines
Background & aims: Patients with early-onset colorectal cancer (eoCRC) are managed according to guidelines that are not age-specific. A multidisciplinary international group (DIRECt), composed of 69 experts, was convened to develop the first evidence-based consensus recommendations for eoCRC. Methods: After reviewing the published literature, a Delphi methodology was used to draft and respond to clinically relevant questions. Each statement underwent 3 rounds of voting and reached a consensus level of agreement of ≥80%. Results: The DIRECt group produced 31 statements in 7 areas of interest: diagnosis, risk factors, genetics, pathology-oncology, endoscopy, therapy, and supportive care. There was strong consensus that all individuals younger than 50 should undergo CRC risk stratification and prompt symptom assessment. All newly diagnosed eoCRC patients should receive germline genetic testing, ideally before surgery. On the basis of current evidence, endoscopic, surgical, and oncologic treatment of eoCRC should not differ from later-onset CRC, except for individuals with pathogenic or likely pathogenic germline variants. The evidence on chemotherapy is not sufficient to recommend changes to established therapeutic protocols. Fertility preservation and sexual health are important to address in eoCRC survivors. The DIRECt group highlighted areas with knowledge gaps that should be prioritized in future research efforts, including age at first screening for the general population, use of fecal immunochemical tests, chemotherapy, endoscopic therapy, and post-treatment surveillance for eoCRC patients. Conclusions: The DIRECt group produced the first consensus recommendations on eoCRC. All statements should be considered together with the accompanying comments and literature reviews. We highlighted areas where research should be prioritized. These guidelines represent a useful tool for clinicians caring for patients with eoCRC
A prospective prostate cancer screening programme for men with pathogenic variants in mismatch repair genes (IMPACT): initial results from an international prospective study.
Funder: Victorian Cancer AgencyFunder: NIHR Manchester Biomedical Research CentreFunder: Cancer Research UKFunder: Cancer Council TasmaniaFunder: Instituto de Salud Carlos IIIFunder: Cancer AustraliaFunder: NIHR Oxford Biomedical Research CentreFunder: Fundación Científica de la Asociación Española Contra el CáncerFunder: Cancer Council South AustraliaFunder: Swedish Cancer SocietyFunder: NIHR Cambridge Biomedical Research CentreFunder: Institut Català de la SalutFunder: Cancer Council VictoriaFunder: Prostate Cancer Foundation of AustraliaFunder: National Institutes of HealthBACKGROUND: Lynch syndrome is a rare familial cancer syndrome caused by pathogenic variants in the mismatch repair genes MLH1, MSH2, MSH6, or PMS2, that cause predisposition to various cancers, predominantly colorectal and endometrial cancer. Data are emerging that pathogenic variants in mismatch repair genes increase the risk of early-onset aggressive prostate cancer. The IMPACT study is prospectively assessing prostate-specific antigen (PSA) screening in men with germline mismatch repair pathogenic variants. Here, we report the usefulness of PSA screening, prostate cancer incidence, and tumour characteristics after the first screening round in men with and without these germline pathogenic variants. METHODS: The IMPACT study is an international, prospective study. Men aged 40-69 years without a previous prostate cancer diagnosis and with a known germline pathogenic variant in the MLH1, MSH2, or MSH6 gene, and age-matched male controls who tested negative for a familial pathogenic variant in these genes were recruited from 34 genetic and urology clinics in eight countries, and underwent a baseline PSA screening. Men who had a PSA level higher than 3·0 ng/mL were offered a transrectal, ultrasound-guided, prostate biopsy and a histopathological analysis was done. All participants are undergoing a minimum of 5 years' annual screening. The primary endpoint was to determine the incidence, stage, and pathology of screening-detected prostate cancer in carriers of pathogenic variants compared with non-carrier controls. We used Fisher's exact test to compare the number of cases, cancer incidence, and positive predictive values of the PSA cutoff and biopsy between carriers and non-carriers and the differences between disease types (ie, cancer vs no cancer, clinically significant cancer vs no cancer). We assessed screening outcomes and tumour characteristics by pathogenic variant status. Here we present results from the first round of PSA screening in the IMPACT study. This study is registered with ClinicalTrials.gov, NCT00261456, and is now closed to accrual. FINDINGS: Between Sept 28, 2012, and March 1, 2020, 828 men were recruited (644 carriers of mismatch repair pathogenic variants [204 carriers of MLH1, 305 carriers of MSH2, and 135 carriers of MSH6] and 184 non-carrier controls [65 non-carriers of MLH1, 76 non-carriers of MSH2, and 43 non-carriers of MSH6]), and in order to boost the sample size for the non-carrier control groups, we randomly selected 134 non-carriers from the BRCA1 and BRCA2 cohort of the IMPACT study, who were included in all three non-carrier cohorts. Men were predominantly of European ancestry (899 [93%] of 953 with available data), with a mean age of 52·8 years (SD 8·3). Within the first screening round, 56 (6%) men had a PSA concentration of more than 3·0 ng/mL and 35 (4%) biopsies were done. The overall incidence of prostate cancer was 1·9% (18 of 962; 95% CI 1·1-2·9). The incidence among MSH2 carriers was 4·3% (13 of 305; 95% CI 2·3-7·2), MSH2 non-carrier controls was 0·5% (one of 210; 0·0-2·6), MSH6 carriers was 3·0% (four of 135; 0·8-7·4), and none were detected among the MLH1 carriers, MLH1 non-carrier controls, and MSH6 non-carrier controls. Prostate cancer incidence, using a PSA threshold of higher than 3·0 ng/mL, was higher in MSH2 carriers than in MSH2 non-carrier controls (4·3% vs 0·5%; p=0·011) and MSH6 carriers than MSH6 non-carrier controls (3·0% vs 0%; p=0·034). The overall positive predictive value of biopsy using a PSA threshold of 3·0 ng/mL was 51·4% (95% CI 34·0-68·6), and the overall positive predictive value of a PSA threshold of 3·0 ng/mL was 32·1% (20·3-46·0). INTERPRETATION: After the first screening round, carriers of MSH2 and MSH6 pathogenic variants had a higher incidence of prostate cancer compared with age-matched non-carrier controls. These findings support the use of targeted PSA screening in these men to identify those with clinically significant prostate cancer. Further annual screening rounds will need to confirm these findings. FUNDING: Cancer Research UK, The Ronald and Rita McAulay Foundation, the National Institute for Health Research support to Biomedical Research Centres (The Institute of Cancer Research and Royal Marsden NHS Foundation Trust; Oxford; Manchester and the Cambridge Clinical Research Centre), Mr and Mrs Jack Baker, the Cancer Council of Tasmania, Cancer Australia, Prostate Cancer Foundation of Australia, Cancer Council of Victoria, Cancer Council of South Australia, the Victorian Cancer Agency, Cancer Australia, Prostate Cancer Foundation of Australia, Asociación Española Contra el Cáncer (AECC), the Instituto de Salud Carlos III, Fondo Europeo de Desarrollo Regional (FEDER), the Institut Català de la Salut, Autonomous Government of Catalonia, Fundação para a Ciência e a Tecnologia, National Institutes of Health National Cancer Institute, Swedish Cancer Society, General Hospital in Malmö Foundation for Combating Cancer
Phenotype comparison of MLH1 and MSH2 mutation carriers in a cohort of 1,914 individuals undergoing clinical genetic testing in the United States
Background and Aims: Lynch syndrome is caused by germ-line mismatch repair gene mutations. We examined the phenotypic differences between MLH1 and MSH2 gene mutation carriers and whether mutation type (point versus large rearrangement) affected phenotypic expression. Methods: This is a cross-sectional prevalence study of 1,914 unrelated probands undergoing clinical genetic testing for MLH1 and MSH2 mutations at a commercial laboratory. Results: Fifteen percent (285 of 1,914) of subjects had pathogenic mutations (112 MLH1, 173 MSH2). MLH1 carriers had a higher prevalence of colorectal cancer (79% versus 69%, P = 0.08) and younger mean age at diagnosis (42.2 versus 44.8 years, P = 0.03) than MSH2 carriers. Forty-one percent of female carriers had endometrial cancer and prevalence was similar in both groups. Other cancers were more frequent in MSH2 carriers (24% versus 9%, P = 0.001) and their families (P < 0.001). Multivariable analyses confirmed these associations. Of the 1,016 subjects who underwent Southern blot analysis, 42 had large rearrangements (7 MLH1, 35 MSH2). There were no phenotypic differences between carriers with large rearrangements and point mutations. Conclusions: In this large study of mismatch repair gene mutation carriers from the United States, MLH1 carriers had more colorectal cancer than MSH2 carriers whereas endometrial cancer prevalence was similar. Large genomic rearrangements were more frequent in the MSH2 gene. MSH2 carriers and their relatives have more extracolonic nonendometrial Lynch syndrome-associated cancers and may benefit from additional screening. Copyrigh
Prevalence and phenotypes of APC and MUTYH mutations in patients with multiple colorectal adenomas
Context: Patients with multiple colorectal adenomas may carry germline mutations in the APC or MUTYH genes. Objectives: To determine the prevalence of pathogenic APC and MUTYH mutations in patients with multiple colorectal adenomas who had undergone genetic testing and to compare the prevalence and clinical characteristics of APC and MUTYH mutation carriers. Design, Setting, and Participants: Cross-sectional study conducted among 8676 individuals who had undergone full gene sequencing and large rearrangement analysis of the APC gene and targeted sequence analysis for the 2 most common MUTYH mutations (Y179C and G396D) between 2004 and 2011. Individuals with either mutation underwent full MUTYH gene sequencing. APC and MUTYH mutation prevalence was evaluated by polyp burden; the clinical characteristics associated with a pathogenic mutation were evaluated using logistic regression analyses. Main Outcome Measure: Prevalence of pathogenic mutations in APC and MUTYH genes. Results: Colorectal adenomas were reported in 7225 individuals; 1457 with classic polyposis (≥100 adenomas) and 3253 with attenuated polyposis (20-99 adenomas). The prevalence of pathogenic APC and biallelic MUTYH mutations was 95 of 119 (80% [95% CI, 71%-87%]) and 2 of 119 (2% [95% CI, 0.2%-6%]), respectively, among individuals with 1000 or more adenomas, 756 of 1338 (56% [95% CI, 54%-59%]) and 94 of 1338 (7% [95% CI, 6%-8%]) among those with 100 to 999 adenomas, 326 of 3253 (10% [95% CI, 9%-11%]) and 233 of 3253 (7% [95% CI, 6%-8%]) among those with 20 to 99 adenomas, and 50 of 970 (5% [95% CI, 4%-7%]) and 37 of 970 (4% [95% CI, 3%-5%]) among those with 10 to 19 adenomas. Adenoma count was strongly associated with a pathogenic mutation in multivariable analyses. Conclusions: Among patients with multiple colorectal adenomas, pathogenic APC and MUTYH mutation prevalence varied considerably by adenoma count, including within those with a classic polyposis phenotype. APC mutations predominated in patients with classic polyposis, whereas prevalence of APC and MUTYH mut