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Riedinger CJ, Esnakula A, Haight PJ, Suarez AA, Chen W, Gillespie J, Villacres A, Chassen A, Cohn DE, Goodfellow PJ, Cosgrove CM. Characterization of mismatch-repair/microsatellite instability-discordant endometrial cancers. Cancer 2024; 130:385-399. [PMID: 37751191 PMCID: PMC10843110 DOI: 10.1002/cncr.35030] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Revised: 08/09/2023] [Accepted: 08/14/2023] [Indexed: 09/27/2023]
Abstract
BACKGROUND Mismatch-repair (MMR)/microsatellite instability (MSI) status has therapeutic implications in endometrial cancer (EC). The authors evaluated the concordance of testing and factors contributing to MMR expression heterogeneity. METHODS Six hundred sixty-six ECs were characterized using immunohistochemistry (IHC), MSI testing, and mut-L homolog 1 (MLH1) methylation. Select samples underwent whole-transcriptome analysis and next-generation sequencing. MMR expression of metastatic/recurrent sites was evaluated. RESULTS MSI testing identified 27.3% of cases as MSI-high (n = 182), MMR IHC identified 25.1% cases as MMR-deficient (n = 167), and 3.8% of cases (n = 25) demonstrated discordant results. A review of IHC staining explained discordant results in 18 cases, revealing subclonal loss of MLH1/Pms 1 homolog 2 (PMS2) (n = 10) and heterogeneous MMR IHC (mut-S homolog 6 [MSH6], n = 7; MLH1/PMS2, n = 1). MSH6-associated Lynch syndrome was diagnosed in three of six cases with heterogeneous expression. Subclonal or heterogeneous cases had a 38.9% recurrence rate (compared with 16.7% in complete MMR-deficient cases and 9% in MMR-proficient cases) and had abnormal MMR IHC results in all metastatic recurrent sites (n = 7). Tumors with subclonal MLH1/PMS2 demonstrated 74 differentially expressed genes (determined using digital spatial transcriptomics) when stratified by MLH1 expression, including many associated with epithelial-mesenchymal transition. CONCLUSIONS Subclonal/heterogeneous MMR IHC cases showed epigenetic loss in 66.7%, germline mutations in 16.7%, and somatic mutations in 16.7%. MMR IHC reported as intact/deficient missed 21% of cases of Lynch syndrome. EC with subclonal/heterogeneous MMR expression demonstrated a high recurrence rate, and metastatic/recurrent sites were MMR-deficient. Transcriptional analysis indicated an increased risk for migration/metastasis, suggesting that clonal MMR deficiency may be a driver for tumor aggressiveness. Reporting MMR IHC only as intact/deficient, without reporting subclonal and heterogeneous staining, misses opportunities for biomarker-directed therapy. PLAIN LANGUAGE SUMMARY Endometrial cancer is the most common gynecologic cancer, and 20%-40% of tumors have a defect in DNA proofreading known as mismatch-repair (MMR) deficiency. These results can be used to guide therapy. Tests for this defect can yield differing results, revealing heterogeneous (mixed) proofreading capabilities. Tumors with discordant testing results and mixed MMR findings can have germline or somatic defects in MMR genes. Cells with deficient DNA proofreading in tumors with mixed MMR findings have DNA expression profiles linked to more aggressive characteristics and cancer spread. These MMR-deficient cells may drive tumor behavior and the risk of spreading cancer.
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Affiliation(s)
- Courtney J. Riedinger
- Department of Obstetrics and Gynecologic, Division of Gynecologic Oncology, The Ohio State University Comprehensive Cancer Center/James Cancer Hospital, Columbus, OH
| | - Ashwini Esnakula
- Department of Pathology, The Ohio State University Wexner Medical Center, Columbus, OH
| | - Paulina J. Haight
- Department of Obstetrics and Gynecologic, Division of Gynecologic Oncology, The Ohio State University Comprehensive Cancer Center/James Cancer Hospital, Columbus, OH
| | - Adrian A. Suarez
- Department of Pathology, The Ohio State University Wexner Medical Center, Columbus, OH
| | - Wei Chen
- Department of Pathology, The Ohio State University Wexner Medical Center, Columbus, OH
| | - Jessica Gillespie
- Department of Obstetrics and Gynecologic, Division of Gynecologic Oncology, The Ohio State University Comprehensive Cancer Center/James Cancer Hospital, Columbus, OH
| | - Alyssa Villacres
- Department of Obstetrics and Gynecologic, Division of Gynecologic Oncology, The Ohio State University Comprehensive Cancer Center/James Cancer Hospital, Columbus, OH
| | - Alexis Chassen
- Department of Obstetrics and Gynecologic, Division of Gynecologic Oncology, The Ohio State University Comprehensive Cancer Center/James Cancer Hospital, Columbus, OH
| | - David E. Cohn
- Department of Obstetrics and Gynecologic, Division of Gynecologic Oncology, The Ohio State University Comprehensive Cancer Center/James Cancer Hospital, Columbus, OH
| | - Paul J. Goodfellow
- Department of Obstetrics and Gynecologic, Division of Gynecologic Oncology, The Ohio State University Comprehensive Cancer Center/James Cancer Hospital, Columbus, OH
| | - Casey M. Cosgrove
- Department of Obstetrics and Gynecologic, Division of Gynecologic Oncology, The Ohio State University Comprehensive Cancer Center/James Cancer Hospital, Columbus, OH
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Metachronous Wilms Tumor, Glioblastoma, and T-cell Leukemia in an Child With Constitutional Mismatch Repair Deficiency syndrome due to Novel Mutation in MSH6 (c.2590G>T). J Pediatr Hematol Oncol 2021; 43:e198-e202. [PMID: 31815888 DOI: 10.1097/mph.0000000000001687] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 11/04/2019] [Indexed: 11/26/2022]
Abstract
Constitutional mismatch repair deficiency (CMMRD) is an autosomal recessively inherited childhood cancer predisposition syndrome results from biallelic germline mutations affecting the key DNA mismatch repair gene: MLH1, MSH2, MSH6, or PMS2. CMMRD is associated with a high risk of developing early onset of central nervous system tumors, hematologic, and intestinal tract tumors. Clinical manifestations, genetic screening, and cancer prevention strategies are limited. In this report we present a patient with metachronous Wilms tumor, glioblastoma, and acute T-cell lymphoblastic leukemia. He had cutaneous features of neurofibromatosis type 1 (NF1). Molecular testing revealed a novel homozygous mutation in MSH6 (c.2590G>T; p.G864*) that has not been reported previously. CMMRD should be considered in patients with cutaneous features similar to NF1 if tumor is found other than expected tumors in NF, early onset cancer, and strong family history of cancer.
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Wang C, Wang Y, Hughes KS, Parmigiani G, Braun D. Penetrance of Colorectal Cancer Among Mismatch Repair Gene Mutation Carriers: A Meta-Analysis. JNCI Cancer Spectr 2020; 4:pkaa027. [PMID: 32923933 PMCID: PMC7476651 DOI: 10.1093/jncics/pkaa027] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022] Open
Abstract
Background Lynch syndrome, the most common colorectal cancer (CRC) syndrome, is caused by germline mismatch repair (MMR) genes. Precise estimates of age-specific risks are crucial for sound counseling of individuals managing a genetic predisposition to cancer, but published risk estimates vary. The objective of this work is to provide gene-, sex-, and age-specific risk estimates of CRC for MMR mutation carriers that comprehensively reflect the best available data. Methods We conducted a meta-analysis to combine risk information from multiple studies on Lynch syndrome-associated CRC. We used a likelihood-based approach to integrate reported measures of CRC risk and deconvolved aggregated information to estimate gene- and sex-specific risk. Results Our comprehensive search identified 10 studies (8 on MLH1, 9 on MSH2, and 3 on MSH6). We estimated the cumulative risk of CRC by age and sex in heterozygous mutation carriers. At age 70 years, for male and female carriers, respectively, risks for MLH1 were 43.9% (95% confidence interval [CI] = 39.6% to 46.6%) and 37.3% (95% CI = 32.2% to 40.2%), for MSH2 were 53.9% (95% CI = 49.0% to 56.3%) and 38.6% (95% CI = 34.1% to 42.0%), and for MSH6 were 12.0% (95% CI = 2.4% to 24.6%) and 12.3% (95% CI = 3.5% to 23.2%). Conclusions Our results provide up-to-date and comprehensive age-specific CRC risk estimates for counseling and risk prediction tools. These will have a direct clinical impact by improving prevention and management strategies for both individuals who are MMR mutation carriers and those considering testing.
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Affiliation(s)
- Cathy Wang
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Data Sciences, Dana-Farber Cancer Institute, Boston, MA, USA
- Correspondence to: Cathy Wang, MS, Department of Biostatistics, Harvard T.H. Chan School of Public Health, Building II, 4th Floor, 655 Huntington Ave, Boston, MA 02215, USA (e-mail: )
| | - Yan Wang
- Division of Surgical Oncology, Massachusetts General Hospital, Boston, MA, USA
- Department of Breast Surgery, Shanghai Cancer Hospital, Fudan University, Shanghai, People’s Republic of China
| | - Kevin S Hughes
- Division of Surgical Oncology, Massachusetts General Hospital, Boston, MA, USA
| | - Giovanni Parmigiani
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Data Sciences, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Danielle Braun
- Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA
- Department of Data Sciences, Dana-Farber Cancer Institute, Boston, MA, USA
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Early onset sporadic colorectal cancer: Worrisome trends and oncogenic features. Dig Liver Dis 2018; 50:521-532. [PMID: 29615301 DOI: 10.1016/j.dld.2018.02.009] [Citation(s) in RCA: 62] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/24/2017] [Revised: 02/09/2018] [Accepted: 02/12/2018] [Indexed: 02/07/2023]
Abstract
Early onset colorectal cancers, defined as arising before 50 years of age, are a growing health hazard in western and eastern countries alike. The incidence of colon and rectal cancers in young individuals is projected to increase by as much as 90% and 140%, respectively, by 2030. Although several known cancer risk factors (e.g. smoking, alcohol, dietary habits) have been investigated, there is no single compelling explanation for this epidemiological trend. While some early onset colorectal cancers have been associated with germline mutations in cancer predisposition genes, genetic syndromes are implicated in only a fraction of these cancers (20%) and do not explain the rising incidence. Colorectal neoplasms develop through microsatellite instability or chromosomal instability pathways, with most of the early onset colorectal cancers exhibiting microsatellite stable phenotypes. Genome-wide hypomethylation is a feature of a subgroup of early onset cancers, which appears to be correlated with chromosomal instability and poor prognosis.
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Sijmons RH, Hofstra RMW. Review: Clinical aspects of hereditary DNA Mismatch repair gene mutations. DNA Repair (Amst) 2015; 38:155-162. [PMID: 26746812 DOI: 10.1016/j.dnarep.2015.11.018] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Revised: 09/28/2015] [Accepted: 11/30/2015] [Indexed: 12/15/2022]
Abstract
Inherited mutations of the DNA Mismatch repair genes MLH1, MSH2, MSH6 and PMS2 can result in two hereditary tumor syndromes: the adult-onset autosomal dominant Lynch syndrome, previously referred to as Hereditary Non-Polyposis Colorectal Cancer (HNPCC) and the childhood-onset autosomal recessive Constitutional Mismatch Repair Deficiency syndrome. Both conditions are important to recognize clinically as their identification has direct consequences for clinical management and allows targeted preventive actions in mutation carriers. Lynch syndrome is one of the more common adult-onset hereditary tumor syndromes, with thousands of patients reported to date. Its tumor spectrum is well established and includes colorectal cancer, endometrial cancer and a range of other cancer types. However, surveillance for cancers other than colorectal cancer is still of uncertain value. Prophylactic surgery, especially for the uterus and its adnexa is an option in female mutation carriers. Chemoprevention of colorectal cancer with aspirin is actively being investigated in this syndrome and shows promising results. In contrast, the Constitutional Mismatch Repair Deficiency syndrome is rare, features a wide spectrum of childhood onset cancers, many of which are brain tumors with high mortality rates. Future studies are very much needed to improve the care for patients with this severe disorder.
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Affiliation(s)
- Rolf H Sijmons
- Department of Genetics, University of Groningen, University Medical Center Groningen, Hanzeplein 1, P.O. Box 30001, 9700RB, Groningen, The Netherlands.
| | - Robert M W Hofstra
- Department of Clinical Genetics, Erasmus Medical Center Rotterdam, P.O. Box 2040, 3000CA Rotterdam, The Netherlands.
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Yuan L, Chi Y, Chen W, Chen X, Wei P, Sheng W, Zhou X, Shi D. Immunohistochemistry and microsatellite instability analysis in molecular subtyping of colorectal carcinoma based on mismatch repair competency. Int J Clin Exp Med 2015; 8:20988-21000. [PMID: 26885030 PMCID: PMC4723875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2015] [Accepted: 10/28/2015] [Indexed: 06/05/2023]
Abstract
Mismatch repair defective (MMRd) colorectal carcinoma (CRC) is a distinct molecular phenotype of colorectal cancer, including 12% of sporadic CRC and 3% of Lynch Syndrome. In order to investigate the clinicopathological characteristics of MMRd colorectal carcinoma, and to find the most effective method for preliminary screening, 296 CRC fulfilled revised Bethesda Guideline (RB) were selected from 1450 CRCs to perform both IHC staining for MLH1, MSH2, MSH6, PMS2 and MSI analysis. Sixty-eight tumors were classified as MSI-H by MSI test. Colorectal carcinomas with MSI-H were prone to be proximal located, poorly differentiated, and relatively early staged, with infrequent metastasis to lymph node as well as to distant organs, compared with MSS ones. All of the 68 MMRd CRCs presented abnormal expression of at least one mismatch repair protein (MMRP), with 48 concurrent negative of MLH1 and PMS2, 14 concurrent negative of MSH2 and MSH6, 4 isolated negative of MSH6, 1 isolated negative of PMS2, and 1 concurrent negative of 4 MMRPs. All of the MLH1 negative tumors also showed abnormal expression of PMS2. All of the MSH2 negative cases also presented negative expression of MSH6. The sensitivity and specificity of the 2-antibody IHC test contained only PMS2 and MSH6 for screening for MMRd CRC were 100% and 98.2% respectively, exactly the same as that of the 4-antibody IHC test with all of the 4 MMRPs. The diagnostic accordance rate of the 2-antibody approach and MSI analysis was 98.6%. In conclusion, MMRd CRC has characteristic clinicopathological features different from MSS CRCs. The 2-antibody IHC approach containing MSH6 and PMS2 is the most easy and effective way to detecting MMR deficiency in CRC.
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Affiliation(s)
- Lin Yuan
- Department of Pathology, Fudan University Shanghai Cancer CenterShanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan UniversityShanghai 200032, China
- Pathology Center, Shanghai General Hospital, School of Medicine, Shanghai Jiao Tong UniversityShanghai 200080, China
| | - Yayun Chi
- Department of Oncology, Shanghai Medical College, Fudan UniversityShanghai 200032, China
- Breast Cancer Institute, Fudan University Shanghai Cancer CenterShanghai 200032, China
| | - Weixiang Chen
- Department of Pathology, Fudan University Shanghai Cancer CenterShanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan UniversityShanghai 200032, China
| | - Xiaochen Chen
- Department of Pathology, Fudan University Shanghai Cancer CenterShanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan UniversityShanghai 200032, China
| | - Ping Wei
- Department of Pathology, Fudan University Shanghai Cancer CenterShanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan UniversityShanghai 200032, China
| | - Weiqi Sheng
- Department of Pathology, Fudan University Shanghai Cancer CenterShanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan UniversityShanghai 200032, China
| | - Xiaoyan Zhou
- Department of Pathology, Fudan University Shanghai Cancer CenterShanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan UniversityShanghai 200032, China
| | - Daren Shi
- Department of Pathology, Fudan University Shanghai Cancer CenterShanghai 200032, China
- Department of Oncology, Shanghai Medical College, Fudan UniversityShanghai 200032, China
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Clinical and Molecular Characterization of Brazilian Patients Suspected to Have Lynch Syndrome. PLoS One 2015; 10:e0139753. [PMID: 26437257 PMCID: PMC4593564 DOI: 10.1371/journal.pone.0139753] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Accepted: 09/15/2015] [Indexed: 12/30/2022] Open
Abstract
Lynch syndrome (LS) accounts for 3–5% of all colorectal cancers (CRC) and is inherited in an autosomal dominant fashion. This syndrome is characterized by early CRC onset, high incidence of tumors in the ascending colon, excess of synchronous/metachronous tumors and extra-colonic tumors. Nowadays, LS is regarded of patients who carry deleterious germline mutations in one of the five mismatch repair genes (MMR), mostly in MLH1 and MSH2, but also in MSH6, PMS1 and PMS2. To comprehensively characterize 116 Brazilian patients suspected for LS, we assessed the frequency of germline mutations in the three minor genes MSH6, PMS1 and PMS2 in 82 patients negative for point mutations in MLH1 and MSH2. We also assessed large genomic rearrangements by MLPA for detecting copy number variations (CNVs) in MLH1, MSH2 and MSH6 generating a broad characterization of MMR genes. The complete analysis of the five MMR genes revealed 45 carriers of pathogenic mutations, including 25 in MSH2, 15 in MLH1, four in MSH6 and one in PMS2. Eleven novel pathogenic mutations (6 in MSH2, 4 in MSH6 and one in PMS2), and 11 variants of unknown significance (VUS) were found. Mutations in the MLH1 and MSH2 genes represented 89% of all mutations (40/45), whereas the three MMR genes (MSH6, PMS1 and PMS2) accounted for 11% (5/45). We also investigated the MLH1 p.Leu676Pro VUS located in the PMS2 interaction domain and our results revealed that this variant displayed no defective function in terms of cellular location and heterodimer interaction. Additionally, we assessed the tumor phenotype of a subset of patients and also the frequency of CRC and extra-colonic tumors in 2,365 individuals of the 116 families, generating the first comprehensive portrait of the genetic and clinical aspects of patients suspected of LS in a Brazilian cohort.
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Snowsill T, Huxley N, Hoyle M, Jones-Hughes T, Coelho H, Cooper C, Frayling I, Hyde C. A systematic review and economic evaluation of diagnostic strategies for Lynch syndrome. Health Technol Assess 2015; 18:1-406. [PMID: 25244061 DOI: 10.3310/hta18580] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Lynch syndrome (LS) is an inherited autosomal dominant disorder characterised by an increased risk of colorectal cancer (CRC) and other cancers, and caused by mutations in the deoxyribonucleic acid (DNA) mismatch repair genes. OBJECTIVE To evaluate the accuracy and cost-effectiveness of strategies to identify LS in newly diagnosed early-onset CRC patients (aged < 50 years). Cascade testing of relatives is employed in all strategies for individuals in whom LS is identified. DATA SOURCES AND METHODS Systematic reviews were conducted of the test accuracy of microsatellite instability (MSI) testing or immunohistochemistry (IHC) in individuals with CRC at risk of LS, and of economic evidence relating to diagnostic strategies for LS. Reviews were carried out in April 2012 (test accuracy); and in February 2012, repeated in February 2013 (economic evaluations). Databases searched included MEDLINE (1946 to April week 3, 2012), EMBASE (1980 to week 17, 2012) and Web of Science (inception to 30 April 2012), and risk of bias for test accuracy was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) quality appraisal tool. A de novo economic model of diagnostic strategies for LS was developed. RESULTS Inconsistencies in study designs precluded pooling of diagnostic test accuracy results from a previous systematic review and nine subsequent primary studies. These were of mixed quality, with significant methodological concerns identified for most. IHC and MSI can both play a part in diagnosing LS but neither is gold standard. No UK studies evaluated the cost-effectiveness of diagnosing and managing LS, although studies from other countries generally found some strategies to be cost-effective compared with no testing. The de novo model demonstrated that all strategies were cost-effective compared with no testing at a threshold of £20,000 per quality-adjusted life-year (QALY), with the most cost-effective strategy utilising MSI and BRAF testing [incremental cost-effectiveness ratio (ICER) = £5491 per QALY]. The maximum health benefit to the population of interest would be obtained using universal germline testing, but this would not be a cost-effective use of NHS resources compared with the next best strategy. When the age limit was raised from 50 to 60 and 70 years, the ICERs compared with no testing increased but remained below £20,000 per QALY (except for universal germline testing with an age limit of 70 years). The total net health benefit increased with the age limit as more individuals with LS were identified. Uncertainty was evaluated through univariate sensitivity analyses, which suggested that the parameters substantially affecting cost-effectiveness: were the risk of CRC for individuals with LS; the average number of relatives identified per index patient; the effectiveness of colonoscopy in preventing metachronous CRC; the cost of colonoscopy; the duration of the psychological impact of genetic testing on health-related quality of life (HRQoL); and the impact of prophylactic hysterectomy and bilateral salpingo-oophorectomy on HRQoL (this had the potential to make all testing strategies more expensive and less effective than no testing). LIMITATIONS The absence of high-quality data for the impact of prophylactic gynaecological surgery and the psychological impact of genetic testing on HRQoL is an acknowledged limitation. CONCLUSIONS Results suggest that reflex testing for LS in newly diagnosed CRC patients aged < 50 years is cost-effective. Such testing may also be cost-effective in newly diagnosed CRC patients aged < 60 or < 70 years. Results are subject to uncertainty due to a number of parameters, for some of which good estimates were not identified. We recommend future research to estimate the cost-effectiveness of testing for LS in individuals with newly diagnosed endometrial or ovarian cancer, and the inclusion of aspirin chemoprevention. Further research is required to accurately estimate the impact of interventions on HRQoL. STUDY REGISTRATION This study is registered as PROSPERO CRD42012002436. FUNDING The National Institute for Health Research Health Technology Assessment programme.
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Affiliation(s)
- Tristan Snowsill
- Peninsula Technology Assessment Group (PenTAG), University of Exeter Medical School, Exeter, UK
| | - Nicola Huxley
- Peninsula Technology Assessment Group (PenTAG), University of Exeter Medical School, Exeter, UK
| | - Martin Hoyle
- Peninsula Technology Assessment Group (PenTAG), University of Exeter Medical School, Exeter, UK
| | - Tracey Jones-Hughes
- Peninsula Technology Assessment Group (PenTAG), University of Exeter Medical School, Exeter, UK
| | - Helen Coelho
- Peninsula Technology Assessment Group (PenTAG), University of Exeter Medical School, Exeter, UK
| | - Chris Cooper
- Peninsula Technology Assessment Group (PenTAG), University of Exeter Medical School, Exeter, UK
| | - Ian Frayling
- Institute of Medical Genetics, Cardiff University, Cardiff, UK
| | - Chris Hyde
- Peninsula Technology Assessment Group (PenTAG), University of Exeter Medical School, Exeter, UK
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Bruegl AS, Djordjevic B, Batte B, Daniels M, Fellman B, Urbauer D, Luthra R, Sun C, Lu KH, Broaddus RR. Evaluation of clinical criteria for the identification of Lynch syndrome among unselected patients with endometrial cancer. Cancer Prev Res (Phila) 2014; 7:686-97. [PMID: 24771847 DOI: 10.1158/1940-6207.capr-13-0359] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Clinical criteria, primarily young age of cancer onset and family history of signature cancers, have been developed to identify individuals at elevated risk for Lynch syndrome with the goals of early identification and cancer prevention. In 2007, the Society of Gynecologic Oncology (SGO)-codified criteria for women presenting with gynecologic cancers. These criteria have not been validated in a population-based setting. For 412 unselected endometrial cancers, immunohistochemical expression of DNA mismatch repair proteins and MLH1 methylation were assessed to classify tumors as sporadic or probable Lynch syndrome (PLS). In this cohort, 10.5% of patients were designated as PLS based on tumor testing. The sensitivity and specificity of the SGO criteria to identify these same cases were 32.6% [95% confidence interval (CI), 19.2-48.5] and 77% (95% CI, 72.7-81.8), respectively. With the exception of tumor location in the lower uterine segment, multivariate analysis of clinical features, family history, and pathologic variables failed to identify significant differences between the sporadic and PLS groups. A simplified cost-effectiveness analysis demonstrated that the SGO clinical criteria and universal tissue testing strategies had comparable costs per patient with PLS identified. In conclusion, the SGO criteria successfully identify PLS cases among women with endometrial cancer who are young or have significant family history of signature tumors. However, a larger proportion of patients with PLS who are older and have less significant family history are not detected by this screening strategy. Universal tissue testing may be necessary to capture more individuals at risk for having Lynch syndrome.
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Affiliation(s)
- Amanda S Bruegl
- Authors' Affiliations: Departments of Gynecologic Oncology and Reproductive Medicine
| | - Bojana Djordjevic
- Department of Pathology and Laboratory Medicine, University of Ottawa, The Ottawa Hospital, Ottawa, Ontario, Canada
| | - Brittany Batte
- Authors' Affiliations: Departments of Gynecologic Oncology and Reproductive Medicine
| | - Molly Daniels
- Authors' Affiliations: Departments of Gynecologic Oncology and Reproductive Medicine
| | | | | | | | - Charlotte Sun
- Authors' Affiliations: Departments of Gynecologic Oncology and Reproductive Medicine
| | - Karen H Lu
- Authors' Affiliations: Departments of Gynecologic Oncology and Reproductive Medicine
| | - Russell R Broaddus
- Pathology, The University of Texas MD Anderson Cancer Center, Houston, Texas; and
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Association between MSH6 G39E polymorphism and cancer susceptibility: a meta-analysis of 7,046 cases and 34,554 controls. Tumour Biol 2014; 35:6029-37. [DOI: 10.1007/s13277-014-1798-z] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2014] [Accepted: 02/25/2014] [Indexed: 10/25/2022] Open
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Ryan S, Jenkins MA, Win AK. Risk of prostate cancer in Lynch syndrome: a systematic review and meta-analysis. Cancer Epidemiol Biomarkers Prev 2014; 23:437-49. [PMID: 24425144 DOI: 10.1158/1055-9965.epi-13-1165] [Citation(s) in RCA: 90] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
It has been controversial that men carrying a DNA mismatch repair (MMR) gene mutation (Lynch syndrome) are at heightened risk of prostate cancer given that an increased risk is likely to be modest and the prevalence of prostate cancer is high. We used PubMed to search for "molecular studies" that reported MMR-deficiency status of prostate cancer tumors in men with an MMR gene mutation, and "risk studies" that reported prostate cancer risk for men known or suspected to have an MMR gene mutation relative to that for noncarriers or the general population. Of the six molecular studies, 32 of 44 [73%, 95% confidence intervals (CI), 57%-85%] prostate cancer tumors in carriers were MMR deficient, which equates to carriers having a 3.67-fold increased risk of prostate cancer (95% CI, 2.32-6.67). Of the 12 risk studies, we estimated a 2.13-fold increased risk of prostate cancer (95% CI, 1.45-2.80) for male carriers in clinic-based retrospective cohorts, 2.11 (95% CI, 1.27-2.95) for male carriers with a prior diagnosis of colorectal cancer, and 2.28 (95% CI, 1.37-3.19) for all men from mutation-carrying families. The combination of evidence from molecular and risk studies in the current literature supports consideration of prostate cancer as part of Lynch syndrome.
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Affiliation(s)
- Shae Ryan
- Authors' Affiliation: Centre for Epidemiology and Biostatistics, Melbourne School of Population and Global Health, The University of Melbourne, Parkville, Victoria, Australia
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Prevalence of Lynch syndrome among patients with newly diagnosed endometrial cancers. PLoS One 2013; 8:e79737. [PMID: 24244552 PMCID: PMC3820559 DOI: 10.1371/journal.pone.0079737] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 09/23/2013] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Lynch syndrome (LS) is a hereditary condition that increases the risk for endometrial and other cancers. The identification of endometrial cancer (EC) patients with LS has the potential to influence life-saving interventions. We aimed to study the prevalence of LS among EC patients in our population. METHODS Universal screening for LS was applied for a consecutive series EC. Tumor testing using microsatellite instability (MSI), immunohistochemistry (IHC) for mismatch-repair (MMR) protein expression and MLH1-methylation analysis, when required, was used to select LS-suspicious cases. Sequencing of corresponding MMR genes was performed. RESULTS One hundred and seventy-three EC (average age, 63 years) were screened. Sixty-one patients (35%) had abnormal IHC or MSI results. After MLH1 methylation analysis, 27 cases were considered suspicious of LS. From these, 22 were contacted and referred for genetic counseling. Nineteen pursued genetic testing and eight were diagnosed of LS. Mutations were more frequent in younger patients (<50 yrs). Three cases had either intact IHC or MSS and reinforce the need of implement the EC screening with both techniques. CONCLUSION The prevalence of LS among EC patients was 4.6% (8/173); with a predictive frequency of 6.6% in the Spanish population. Universal screening of EC for LS is recommended.
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Lastra E, García-González M, Llorente B, Bernuy C, Barrio MJ, Pérez-Cabornero L, Durán M, García-Girón C. Lynch syndrome diagnostics: decision-making process for germ-line testing. Clin Transl Oncol 2012; 14:254-62. [PMID: 22484632 DOI: 10.1007/s12094-012-0793-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Cancer risks and medical management of Lynch syndrome (LS) differ from other hereditary or familial clustering of colorectal cancer. Differential diagnosis has improved as a result of the growing clinical and molecular knowledge about LS. Appropriate application of these advances in several scenarios constitutes a decision-making process to further decide germ-line testing with accuracy and efficiency. However, an only molecular-screening algorithm, with a limited number of steps and choices, may be difficult to devise. How, when, where and at what expense to use the different diagnostic tools remain dynamic and changeable under different circumstances. From a clinical point of view, it is advisable to discuss conflicting aspects to guide LS diagnosis.
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Affiliation(s)
- E Lastra
- Unidad de Consejo Genético Este Castilla y León, Sección de Oncología Médica, Complejo Asistencial Universitario de Burgos, Hospital General Yagüe, Burgos, Spain.
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15
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Legolvan MP, Taliano RJ, Resnick MB. Application of molecular techniques in the diagnosis, prognosis and management of patients with colorectal cancer: a practical approach. Hum Pathol 2012; 43:1157-68. [PMID: 22658275 DOI: 10.1016/j.humpath.2012.03.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 02/29/2012] [Accepted: 03/02/2012] [Indexed: 12/13/2022]
Abstract
There has been an increasing role for molecular diagnostics in the diagnosis and management of cancer, and colorectal carcinoma is no exception. Recent molecular advances have elucidated 3 broad molecular subtypes of colorectal cancer, including chromosomal instability, microsatellite instability, and cytosine-phosphoguanine island methylator phenotype, which will be discussed. Also, the common syndromes associated with colorectal carcinoma will be reviewed with a focus on the differentiation between Lynch syndrome and microsatellite unstable tumors. Molecular biomarkers for predictive and prognostic markers are also becoming widely used, and due to the clinical use of monoclonal antibodies to the epidermal growth factor receptor, an emphasis is placed on that pathway.
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Affiliation(s)
- Mark P Legolvan
- Department of Pathology, Rhode Island Hospital, and the Alpert Medical School of Brown University, Providence, RI 02908, USA
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Mojtahed A, Schrijver I, Ford JM, Longacre TA, Pai RK. A two-antibody mismatch repair protein immunohistochemistry screening approach for colorectal carcinomas, skin sebaceous tumors, and gynecologic tract carcinomas. Mod Pathol 2011; 24:1004-14. [PMID: 21499234 DOI: 10.1038/modpathol.2011.55] [Citation(s) in RCA: 86] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Mismatch repair protein immunohistochemistry is a widely used method for detecting patients at risk for Lynch syndrome. Recent data suggest that a two-antibody panel approach using PMS2 and MSH6 is an effective screening protocol for colorectal carcinoma, but there are limited data concerning this approach for extraintestinal tumors. The purpose of this study was to review the utility of a two-antibody panel approach in colorectal carcinoma and extraintestinal tumors. We evaluated mismatch repair protein expression in two cohorts: (1) a retrospective analysis of intestinal and extraintestinal tumors (n=334) tested for mismatch repair protein immunohistochemistry and (2) a prospectively accrued series of intestinal, gynecologic tract, and skin sebaceous neoplasms (n=98). A total of 432 cases were analyzed, including 323 colorectal, 50 gynecologic tract, 49 skin sebaceous, and 10 other neoplasms. Overall, 102/432 tumors (24%) demonstrated loss of at least one mismatch repair protein. Concurrent loss of MLH1 and PMS2 was the most common pattern of abnormal expression (50/432, 12%) followed by concurrent loss of MSH2 and MSH6 (33/432, 8%). Of 55 cases with abnormal PMS2 expression, 5 (9%) demonstrated isolated loss of PMS2 expression. Of 47 cases with abnormal MSH6 expression, 14 (30%) demonstrated isolated loss of MSH6 expression. Isolated loss of MLH1 or MSH2 was not observed. Colorectal carcinomas more frequently demonstrated abnormal expression of PMS2 (39/59, 66%). Skin sebaceous neoplasms more frequently demonstrated abnormal expression of MSH6 (18/24, 75%, respectively). A total of 65 tumors with abnormal mismatch repair protein expression were tested for microsatellite instability (MSI): 47 (72%) MSI high, 9 (14%) MSI low, and 9 (14%) microsatellite stable (MSS). Abnormal MSH6 expression accounted for 14/18 (78%) cases that were MSS or MSI low. Our findings confirm the utility of a two-antibody approach using PMS2 and MSH6 in colorectal carcinoma and indicate that this approach is effective in extraintestinal neoplasms associated with Lynch syndrome.
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Zaanan A, Meunier K, Sangar F, Fléjou JF, Praz F. Microsatellite instability in colorectal cancer: from molecular oncogenic mechanisms to clinical implications. Cell Oncol (Dordr) 2011; 34:155-76. [PMID: 21484480 DOI: 10.1007/s13402-011-0024-x] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2011] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Microsatellite instability (MSI) constitutes an important oncogenic molecular pathway in colorectal cancer (CRC), representing approximately 15% of all colorectal malignant tumours. In roughly one third of the cases, the underlying DNA mismatch repair (MMR) defect is inherited through the transmission of a mutation in one of the genes involved in MMR, predominantly MSH2 and MLH1, or less frequently, MSH6 or PMS2. In the overwhelming number of sporadic cases, MSI results from epigenetic MLH1 silencing through hypermethylation of its promoter. MMR deficiency promotes colorectal oncogenesis through the accumulation of numerous mutations in crucial target genes harbouring mononucleotide repeats, notably in those involved in the control of cell proliferation and differentiation, as well as DNA damage signalling and repair. DESIGN In this review, we describe the molecular aspects of the MMR system and the biological consequences of its defect on the oncogenic process, and we discuss the various experimental systems used to evaluate the efficacy of cytotoxic drugs on MSI colorectal cells lines. There is increasing evidence showing that MSI CRCs differ from all CRCs in terms of prognosis and response to the treatment. We report the clinical studies that have evaluated the prognostic and predictive value of MSI status on clinical outcome in patients treated with various chemotherapy regimens used in the adjuvant setting or for advanced CRCs. CONCLUSION In view of this, the opportunity of a systematic MSI phenotyping in the clinical management of patients with CRC is further discussed.
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Affiliation(s)
- Aziz Zaanan
- INSERM, UMR_S, Centre de Recherche Saint-Antoine, Paris, France
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Power DG, Gloglowski E, Lipkin SM. Clinical genetics of hereditary colorectal cancer. Hematol Oncol Clin North Am 2011; 24:837-59. [PMID: 20816577 DOI: 10.1016/j.hoc.2010.06.006] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Colorectal cancer (CRC) is a common disease, and approximately 25% of patients have a familial component. High-penetrance singlegene germline mutations conferring a true hereditary susceptibility account for around 5% to 6% of all cases. Lynch syndrome is the most common hereditary form of colorectal cancer. Much of the hereditary component in the remaining familial cases of CRC is likely polygenic, and many of the genetic changes involved are as yet unidentified. This article addresses the most clinically important CRC genetic syndromes.
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Affiliation(s)
- Derek G Power
- Clinical Genetics, Department of Medicine, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA
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Dinh TA, Rosner BI, Atwood JC, Boland CR, Syngal S, Vasen HFA, Gruber SB, Burt RW. Health benefits and cost-effectiveness of primary genetic screening for Lynch syndrome in the general population. Cancer Prev Res (Phila) 2010; 4:9-22. [PMID: 21088223 DOI: 10.1158/1940-6207.capr-10-0262] [Citation(s) in RCA: 141] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
In current clinical practice, genetic testing to detect Lynch syndrome mutations ideally begins with diagnostic testing of an individual affected with cancer before offering predictive testing to at-risk relatives. An alternative strategy that warrants exploration involves screening unaffected individuals via demographic and family histories, and offering genetic testing to those individuals whose risks for carrying a mutation exceed a selected threshold. Whether this approach would improve health outcomes in a manner that is cost-effective relative to current standards of care has yet to be demonstrated. To do so, we developed a simulation framework that integrated models of colorectal and endometrial cancers with a 5-generation family history model to predict health and economic outcomes of 20 primary screening strategies (at a wide range of compliance levels) aimed at detecting individuals with mismatch repair gene mutations and their at-risk relatives. These strategies were characterized by (i) different screening ages for starting risk assessment and (ii) different risk thresholds above which to implement genetic testing. For each strategy, 100,000 simulated individuals, representative of the U.S. population, were followed from the age of 20, and the outcomes were compared with current practice. Findings indicated that risk assessment starting at ages 25, 30, or 35, followed by genetic testing of those with mutation risks exceeding 5%, reduced colorectal and endometrial cancer incidence in mutation carriers by approximately 12.4% and 8.8%, respectively. For a population of 100,000 individuals containing 392 mutation carriers, this strategy increased quality-adjusted life-years (QALY) by approximately 135 with an average cost-effectiveness ratio of $26,000 per QALY. The cost-effectiveness of screening for mismatch repair gene mutations is comparable to that of accepted cancer screening activities in the general population such as colorectal cancer screening, cervical cancer screening, and breast cancer screening. These results suggest that primary screening of individuals for mismatch repair gene mutations, starting with risk assessment between the ages of 25 and 35, followed by genetic testing of those whose risk exceeds 5%, is a strategy that could improve health outcomes in a cost-effective manner relative to current practice.
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Affiliation(s)
- Tuan A Dinh
- Archimedes, Inc, San Francisco, California, USA
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Abstract
An estimated 150,000 individuals are diagnosed with colorectal carcinoma (CRC) each year, and approximately 50,000 will die from this disease, making CRC the third leading cause of cancer deaths in the United States. For this reason, an enormous amount of effort has been spent to understand the molecular pathogenesis of this disease and to develop screening tests and prognostic markers. In the last 10 years, there has been a revolution in the understanding of CRC due to the identification of multiple distinct molecular pathways. With the introduction of biologic agents that target particular subtypes of CRC, molecular analysis of CRC is becoming standard of care in surgical pathology. In this context, the authors first describe the multiple molecular pathways leading to CRC and then discuss the role of molecular testing in the diagnosis of Lynch syndrome (formerly hereditary nonpolyposis colorectal carcinoma), prognosis, and therapy.
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Affiliation(s)
- Reetesh K Pai
- Department of Pathology, Stanford University Medical Center, Stanford University School of Medicine, 300 Pasteur Drive, L235 MC 5324, Stanford, CA 94305, USA
| | - Rish K Pai
- Division of Anatomic and Molecular Pathology, Department of Pathology and Immunology, Washington University School of Medicine, 660 South Euclid Avenue, Box 8118, St Louis, MO 63110, USA.
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Baglietto L, Lindor NM, Dowty JG, White DM, Wagner A, Gomez Garcia EB, Vriends AHJT, Cartwright NR, Barnetson RA, Farrington SM, Tenesa A, Hampel H, Buchanan D, Arnold S, Young J, Walsh MD, Jass J, Macrae F, Antill Y, Winship IM, Giles GG, Goldblatt J, Parry S, Suthers G, Leggett B, Butz M, Aronson M, Poynter JN, Baron JA, Le Marchand L, Haile R, Gallinger S, Hopper JL, Potter J, de la Chapelle A, Vasen HF, Dunlop MG, Thibodeau SN, Jenkins MA. Risks of Lynch syndrome cancers for MSH6 mutation carriers. J Natl Cancer Inst 2010; 102:193-201. [PMID: 20028993 PMCID: PMC2815724 DOI: 10.1093/jnci/djp473] [Citation(s) in RCA: 263] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2009] [Revised: 11/10/2009] [Accepted: 11/17/2009] [Indexed: 01/03/2023] Open
Abstract
BACKGROUND Germline mutations in MSH6 account for 10%-20% of Lynch syndrome colorectal cancers caused by hereditary DNA mismatch repair gene mutations. Because there have been only a few studies of mutation carriers, their cancer risks are uncertain. METHODS We identified 113 families of MSH6 mutation carriers from five countries that we ascertained through family cancer clinics and population-based cancer registries. Mutation status, sex, age, and histories of cancer, polypectomy, and hysterectomy were sought from 3104 of their relatives. Age-specific cumulative risks for carriers and hazard ratios (HRs) for cancer risks of carriers, compared with those of the general population of the same country, were estimated by use of a modified segregation analysis with appropriate conditioning depending on ascertainment. RESULTS For MSH6 mutation carriers, the estimated cumulative risks to ages 70 and 80 years, respectively, were as follows: for colorectal cancer, 22% (95% confidence interval [CI] = 14% to 32%) and 44% (95% CI = 28% to 62%) for men and 10% (95% CI = 5% to 17%) and 20% (95% CI = 11% to 35%) for women; for endometrial cancer, 26% (95% CI = 18% to 36%) and 44% (95% CI = 30% to 58%); and for any cancer associated with Lynch syndrome, 24% (95% CI = 16% to 37%) and 47% (95% CI = 32% to 66%) for men and 40% (95% CI = 32% to 52%) and 65% (95% CI = 53% to 78%) for women. Compared with incidence for the general population, MSH6 mutation carriers had an eightfold increased incidence of colorectal cancer (HR = 7.6, 95% CI = 5.4 to 10.8), which was independent of sex and age. Women who were MSH6 mutation carriers had a 26-fold increased incidence of endometrial cancer (HR = 25.5, 95% CI = 16.8 to 38.7) and a sixfold increased incidence of other cancers associated with Lynch syndrome (HR = 6.0, 95% CI = 3.4 to 10.7). CONCLUSION We have obtained precise and accurate estimates of both absolute and relative cancer risks for MSH6 mutation carriers.
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Affiliation(s)
- Laura Baglietto
- Cancer Epidemiology Centre, Victorian Cancer Registry, Carlton, Victoria, Australia
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Abstract
In comparison with the mismatch repair genes MLH1 and MSH2, the genes MSH6 and PMS2 are relatively understudied with respect to cancer risk. However, some recent large studies of data combined from several sources, using analytic methods that appropriately condition on the varying methods of ascertainment, are producing reasonably precise estimates, which can be used for risk estimation in patients. To identify modifiers for risk in such carriers, a goal for epidemiologists to improve the health of carriers, such collaborative studies need to continue and expand to include additional mutation carriers in which lifestyle factors and DNA samples are available for analysis.
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Affiliation(s)
- Mark A Jenkins
- Centre for MEGA Epidemiology, School of Population Health, The University of Melbourne, Victoria 3010, Australia.
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Lynch Syndrome Screening Strategies Among Newly Diagnosed Endometrial Cancer Patients. Obstet Gynecol 2009; 114:530-536. [DOI: 10.1097/aog.0b013e3181b11ecc] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
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Resnick KE, Hampel H, Fishel R, Cohn DE. Current and emerging trends in Lynch syndrome identification in women with endometrial cancer. Gynecol Oncol 2009; 114:128-34. [PMID: 19375789 PMCID: PMC2841434 DOI: 10.1016/j.ygyno.2009.03.003] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2008] [Revised: 02/25/2009] [Accepted: 03/04/2009] [Indexed: 11/24/2022]
Abstract
OBJECTIVE Lynch syndrome is a heritable, cancer susceptibility syndrome. This study aims to review current and emerging trends in the identification of Lynch syndrome in the endometrial cancer patient population. METHODS We performed a comprehensive review of past and present screening algorithms for Lynch syndrome, including a review of the utility of both the Amsterdam criteria and Bethesda guidelines. Because non-colon cancers have historically not been the focus of Lynch syndrome research, current literature is ripe with questions regarding screening among this patient population. Low BMI, age less than 50, positive family history and pathologic features have all been identified as risk factors in endometrial cancer patients who might benefit from Lynch screening. Additionally, based on experience at our own institution we offer a feasible screening algorithm for these patients. RESULTS A comprehensive review of the data demonstrated that immunohistochemistry is becoming an efficient, inexpensive way to screen tumors at risk for mismatch repair deficiency. The sensitivity and specificity of immunohistochemistry for predicting Lynch syndrome approaches 100%. Ideally, prospective screening of all endometrial cancer patients with IHC is a feasible, cost-efficient way to detect Lynch in this patient population given the limitations of using personal/family history of malignancy as well as pathologic risk factors. CONCLUSION It is imperative that clinicians be mindful of the risk of Lynch syndrome in women with endometrial cancer. Given the opportunity for colon cancer screening and prevention strategies to be initiated, the identification of probands with endometrial cancer as a result of Lynch syndrome will lead to a reduction in morbidity and mortality for these patients and their families.
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Affiliation(s)
- Kimberly E. Resnick
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, The Ohio State University College of Medicine, Columbus, OH 43210, USA
| | - Heather Hampel
- Human Cancer Genetics, The Ohio State University College of Medicine, Columbus, OH 43210, USA
| | - Richard Fishel
- Department of Molecular Virology, Immunology and Medical Genetics, The Ohio State University College of Medicine, Columbus, OH 43210, USA
| | - David E. Cohn
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, The Ohio State University College of Medicine, Columbus, OH 43210, USA
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Hereditary non-polyposis colorectal cancer or Lynch syndrome: the gynaecological perspective. Curr Opin Obstet Gynecol 2009; 21:31-8. [PMID: 19125001 DOI: 10.1097/gco.0b013e32831c844d] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
PURPOSE OF REVIEW Hereditary non-polyposis colorectal cancer (HNPCC) or Lynch syndrome is characterized by a number of other cancers including colorectal, endometrial and ovarian cancer. This review covers the gynaecological aspects of managing women with HNPCC: diagnostic criteria, molecular tests for diagnosis, cancer risks and different strategies for surveillance and prevention. RECENT FINDINGS Studies correcting for ascertainment bias found slightly lower penetrance estimates than those obtained from high-risk families. HNPCC linked ovarian cancer presents at an earlier age and stage and has similar survival rates as sporadic cancer. In endometrial tumours, microsatellite instability or immunohistochemistry has limited effectiveness in selecting individuals for genetic testing, due to molecular differences. Population-based data indicate that a significant proportion of mismatch repair gene carriers would be missed by current clinical criteria. Effective risk prediction models complement clinical risk assessment. Effectiveness of screening is unproven and prophylactic surgery is the best preventive option for women who have completed their families. Multimodal screening protocols from the age of 30-35 years are being evaluated. SUMMARY Risk of endometrial cancer in women with Lynch syndrome is as high as the risk of colorectal cancer. Further research is needed to identify the appropriate strategy for clinical risk assessment and optimize screening. A multidisciplinary approach is necessary to manage these women.
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Abstract
Hereditary nonpolyposis colorectal cancer, or Lynch syndrome, is responsible for 2-3% of all colorectal cancers. Lynch syndrome is also associated with a high risk of extracolonic cancers, including endometrial, stomach, small bowel, pancreas, biliary tract, ovary, urinary tract, brain, and skin cancer. In this Review, we discuss the risks, surveillance tests, and guidelines for the management of extracolonic tumours associated with Lynch syndrome. For all types of extracolonic cancer, evidence supporting surveillance is scarce. A benefit of surveillance is evident only for endometrial cancer, where transvaginal ultrasound and endometrial sampling detect tumours in early stages. Surveillance is generally recommended for urinary tract and gastric cancer, especially in families with more than one member with these types of cancer. For the other types of cancer, surveillance is typically not recommended. Prophylactic hysterectomy and bilateral salpingo-oophorectomy should be considered for women with Lynch syndrome who are past childbearing age, especially during surgery for colorectal cancer. No data show efficacy of chemopreventive drugs in reducing the risk of extracolonic cancers for patients with Lynch syndrome.
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EGAPP supplementary evidence review: DNA testing strategies aimed at reducing morbidity and mortality from Lynch syndrome. Genet Med 2009; 11:42-65. [PMID: 19125127 DOI: 10.1097/gim.0b013e31818fa2db] [Citation(s) in RCA: 353] [Impact Index Per Article: 23.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
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Rouprêt M, Yates DR, Comperat E, Cussenot O. Upper urinary tract urothelial cell carcinomas and other urological malignancies involved in the hereditary nonpolyposis colorectal cancer (lynch syndrome) tumor spectrum. Eur Urol 2008; 54:1226-36. [PMID: 18715695 DOI: 10.1016/j.eururo.2008.08.008] [Citation(s) in RCA: 137] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2008] [Accepted: 08/04/2008] [Indexed: 12/20/2022]
Abstract
CONTEXT The data describing the urologic extracolonic cancers associated with hereditary nonpolyposis colorectal cancer (HNPCC) are variable. OBJECTIVE Provide an update about the current urologic tumor spectrum in HNPCC. EVIDENCE ACQUISITION Data on HNPCC extracolonic tumor spectrum published in the literature were analysed using MEDLINE with emphasis on urological malignancies, upper tract tumors, clinical criteria, genetic diagnosis and counselling. EVIDENCE SYNTHESIS HNPCC is a form of colorectal cancer with a dominant autosomal mode of inheritance. HNPCC is caused by germ-line mutations affecting one or several mismatch repair genes. Cancers other than colorectal cancer are sometimes associated with HNPCC. These include specific urological malignancies, most notably tumors of the upper urinary tract, which have been reported to occur at a rate x22 higher than the general population. Upper urinary tract tumors rank third (5%) after colon (63%) and endometrial (9%) cancer within the group of HNPCC related tumors. Prostate cancer and testicular germ cell tumors are rarely associated. Due to lack of appreciation of such hereditary associations, some inherited cancers are still misclassified as sporadic and their incidence is underestimated. The biological tests requested in suspected cases of HNPCC are: microsatellite instability (MSI) analysis, immunohistochemistry and DNA sequencing. When gene mutations are detected, the patient and their family will benefit from a multidisciplinary management approach. The presence of other HNPCC-associated cancers is sought and close monitoring of patients is undertaken. Genetic counselling is provided to the patient's family. CONCLUSIONS The recognized urologic tumor spectrum in HNPCC includes upper tract tumors. However, in order not to overlook a hereditary cancer, urologists should be aware of the possible urological malignancies associated with HNPCC (i.e., prostate and testicular carcinomas) and evaluate appropriately anyone they feel are at high risk of underlying HNPCC based on set clinical criteria.
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Affiliation(s)
- Morgan Rouprêt
- Hôpital Pitié-Salpêtrière, Academic Urology Department, 47-83 Boulevard de l'Hôpital, 75013 Paris, France.
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Zhang L. Immunohistochemistry versus microsatellite instability testing for screening colorectal cancer patients at risk for hereditary nonpolyposis colorectal cancer syndrome. Part II. The utility of microsatellite instability testing. J Mol Diagn 2008; 10:301-7. [PMID: 18556776 DOI: 10.2353/jmoldx.2008.080062] [Citation(s) in RCA: 151] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
Germline mutations in the mismatch repair genes mutL homolog 1 (MLH1) and mutS homolog 2 (MSH2), MSH6, and postmeiotic segregation increased 2 (PMS2) lead to the development of hereditary nonpolyposis colorectal cancer (HNPCC). Diagnosis of HNPCC relies on the compilation of a thorough family history of cancer, documentation of pathological findings, tumor testing for microsatellite instability (MSI) and immunohistochemistry (IHC), and germline mutation analysis of the suspected genes. As a hallmark of HNPCC, microsatellite instability is widely accepted as a primary method for identifying individuals at risk for HNPCC. It serves as an excellent, easy-to-evaluate marker of mismatch repair deficiency. Recent improvements in MSI testing have significantly enhanced the accuracy and reduced its cost. Proficiency testing for MSI is available, and laboratory-to-laboratory reproducibility of such testing can be easily evaluated. In addition, the combination of microsatellite instability testing, MLH1 promoter methylation analysis, and BRAF (V600E) mutation analysis can distinguish a sporadic colorectal cancer from one associated with HNPCC, helping to avoid costly molecular genetic testing for germline mutations in mismatch repair genes. In this article, we discuss the development of MSI markers used for HNPCC screening and focus on the advantages and disadvantages of MSI testing in screening for HNPCC patients. We conclude that MSI is as sensitive and specific as IHC, given its excellent reproducibility and its potential capability to indicate mutations not be detected by IHC. MSI has been used and will continue to prevail as the primary screening tool for identifying HNPCC patients.
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Affiliation(s)
- Liying Zhang
- Department of Pathology, Memorial Sloan-Kettering Cancer Center, New York, NY 10065, USA.
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Kurnat-Thoma EL. Hereditary nonpolyposis colorectal cancer (Lynch syndrome): molecular pathogenesis and clinical approaches to diagnosis and management for nurses. Biol Res Nurs 2008; 9:185-99. [PMID: 18077771 DOI: 10.1177/1099800407308558] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Hereditary nonpolyposis colorectal cancer (HNPCC), also referred to as Lynch syndrome, is the most common form of hereditary colorectal cancer and is responsible for 2% to 4% of all colorectal cancers in the Western hemisphere. Generally characterized by early-onset colorectal carcinoma with a mean age of presentation of 40 to 45 years, it can also manifest with extracolonic adenocarcinomas and cancers of the endometrium, ovaries, stomach, pancreas, small intestine, hepatobiliary tract, upper uroepithelial tract, brain, and skin. HNPCC is autosomal dominant and carries an 80% lifetime risk of cancer development. This review addresses the molecular underpinnings of HNPCC while providing a concise approach to clinical detection, diagnosis, and management of patients who may or may not test positive for an HNPCC-causing mutation. Although applicable to any patient-care setting in which cancer may be observed, this review specifically addresses the role of nurses in detecting, diagnosing, and clinically managing HNPCC.
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Affiliation(s)
- Emma L Kurnat-Thoma
- National Institutes of Health/National Institute of Nursing Research Graduate Partnership Program Scholar, University of Utah, Salt Lake City, USA. kurnate@ mail.nih.gov
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Thyroid cancer in a patient with a germline MSH2 mutation. Case report and review of the Lynch syndrome expanding tumour spectrum. Hered Cancer Clin Pract 2008; 6:15-21. [PMID: 19706203 PMCID: PMC2735069 DOI: 10.1186/1897-4287-6-1-15] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Accepted: 02/14/2008] [Indexed: 12/15/2022] Open
Abstract
Lynch syndrome (HNPCC) is a dominantly inherited disorder characterized by germline defects in DNA mismatch repair (MMR) genes and the development of a variety of cancers, predominantly colorectal and endometrial. We present a 44-year-old woman who was shown to carry the truncating MSH2 gene mutation that had previously been identified in her family. Recently, she had been diagnosed with an undifferentiated carcinoma of the thyroid and an adenoma of her coecum. Although the thyroid carcinoma was not MSI-high (1 out of 5 microsatellites instable), it did show complete loss of immunohistochemical expression for the MSH2 protein, suggesting that this tumour was not coincidental. Although the risks for some tumour types, including breast cancer, soft tissue sarcoma and prostate cancer, are not significantly increased in Lynch syndrome, MMR deficiency in the presence of a corresponding germline defect has been demonstrated in incidental cases of a growing range of tumour types, which is reviewed in this paper. Interestingly, the MSH2-associated tumour spectrum appears to be wider than that of MLH1 and generally the risk for most extra-colonic cancers appears to be higher for MSH2 than for MLH1 mutation carriers. Together with a previously reported case, our findings show that anaplastic thyroid carcinoma can develop in the setting of Lynch syndrome. Uncommon Lynch syndrome-associated tumour types might be useful in the genetic analysis of a Lynch syndrome suspected family if samples from typical Lynch syndrome tumours are unavailable.
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Roncari B, Pedroni M, Maffei S, Di Gregorio C, Ponti G, Scarselli A, Losi L, Benatti P, Roncucci L, De Gaetani C, Camellini L, Lucci-Cordisco E, Tricarico R, Genuardi M, Ponz de Leon M. Frequency of constitutional MSH6 mutations in a consecutive series of families with clinical suspicion of HNPCC. Clin Genet 2007; 72:230-7. [PMID: 17718861 DOI: 10.1111/j.1399-0004.2007.00856.x] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A large majority of constitutional mutations in hereditary non-polyposis colorectal cancer (HNPCC) are because of the MHL 1 or MSH 2 genes. In a lower fraction of cases, another gene of the mismatch repair (MMR) machinery, MSH6, may be responsible. Families with MSH6 mutations are difficult to recognize, as microsatellite instability (MSI) may not be detectable and immunohistochemistry (IHC) may give ambiguous results. In the present study, we proposed (i) to determine the frequency of MSH6 mutations in a selected population of colorectal cancer patients obtained from a tumor registry, (ii) to assess whether IHC is a suitable tool for selecting and identifying MSH6 mutation carriers. One hundred neoplasms of the large bowel from suspected HNPCC families were analyzed for MSI (BAT 25 and BAT 26 markers) and immunohistochemical expression of the MSH6 protein. We found on 12 tumors (from different families) showing instability or lack of MSH6 expression. Among these, four potentially pathogenic MSH6 mutations were detected (del A at 2984; del TT at 3119; del AGG cod 385; and del CGT cod 1242) by direct gene sequencing. These represented 12.9% of all families with constitutional mutations of the DNA MMR genes. Thus, some 5% of all HNPCC families are featured by constitutional mutation of the MSH6 gene. This appears, however, as a minimum estimate; routine use of IHC and the study of large numbers of individuals and families with little or no evidence of Lynch syndrome might reveal that mutation of this gene account for a large fraction of HNPCC.
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Affiliation(s)
- B Roncari
- Department of Medicine and Medical Specialties, University of Modena and Reggio Emilia, Modena, Italy
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Abstract
Single-gene germline mutations conferring a high lifetime risk of colorectal cancer (CRC) account for up to 6% of all CRC cases. The most widely studied monogenic colorectal cancer syndromes include familial adenomatous polyposis (FAP) and Lynch syndrome. However, additional syndromes continue to be defined and new predisposition genes are continuing to be identified. Most recently, MYH-associated polyposis (MAP) and an "atypical Lynch syndrome" related to the presence of MSH6 mutations have been linked to an increased risk of CRC. In this review, we summarize basic information related to these newly recognized gene mutations, including the accumulating data on the prevalence and penetrance of deleterious mutations, as well as the management options for identified carriers and their families. Recognizing these heritable syndromes is essential and predictive genetic testing will continue to transform the field of cancer risk assessment by offering the opportunity to focus on more precise risk management and cancer prevention.
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Affiliation(s)
- Fay Kastrinos
- Division of Gastroenterology, Brigham and Women's Hospital, Boston, MA, USA
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Lynch HT, Boland CR, Rodriguez-Bigas MA, Amos C, Lynch JF, Lynch PM. Who should be sent for genetic testing in hereditary colorectal cancer syndromes? J Clin Oncol 2007; 25:3534-42. [PMID: 17687158 DOI: 10.1200/jco.2006.10.3119] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Genetic testing is being adopted increasingly to identify individuals with germline mutations that predispose to hereditary colorectal cancer syndromes. Deciding who to test and for which syndrome is of concern to members of the GI oncology community, molecular geneticists, and genetic counselors. The purpose of this review is to help provide guidelines for testing, given that the results influence syndrome diagnosis and clinical management. Although family history may determine whether testing is appropriate and may direct testing to the most informative family member, evolving clinicopathologic features can identify individual patients who warrant testing. Thus, although the usual absence of clinical premonitory signs in hereditary nonpolyposis colorectal cancer (or Lynch syndrome) adds difficulty to its diagnosis, use of the Amsterdam Criteria and Bethesda Guidelines can prove helpful. In contrast, premonitory stigmata such as pigmentations in Peutz-Jeghers syndrome and the phenotypic features of familial adenomatous polyposis aid significantly in syndrome diagnosis. We conclude that the physician's role in advising DNA testing is no small matter, given that a hereditary cancer syndrome's sequelae may be far reaching. Genetic counselors may be extremely helpful to the practicing gastroenterologist, oncologist, or surgeon; when more specialized knowledge is called for, referral can be made to a medical geneticist and/or a medical genetics clinic.
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Affiliation(s)
- Henry T Lynch
- Department of Preventive Medicine, Creighton University School of Medicine, Omaha, NE 68178, USA.
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Young LC, Keuling AM, Lai R, Nation PN, Tron VA, Andrew SE. The associated contributions of p53 and the DNA mismatch repair protein Msh6 to spontaneous tumorigenesis. Carcinogenesis 2007; 28:2131-8. [PMID: 17615258 DOI: 10.1093/carcin/bgm153] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
DNA mismatch repair (MMR) is a highly conserved system that repairs DNA adducts acquired during replication, as well as some forms of exogenous/endogenous DNA damage. Additionally, MMR proteins bind to DNA adducts that are not removed by MMR and influence damage-response mechanisms other than repair. Hereditary non-polyposis colorectal cancer, as well as mouse models for MMR deficiency, illustrate that MMR proteins are required for maintenance of genetic stability and tumor suppression. In both humans and mice, the phenotype associated with Msh6-associated tumorigenesis is distinct from that of Msh2. In this study, we hypothesized that Msh6-/-;p53+/- mice would display earlier tumor onset than their Msh6-/- or p53+/- counterparts, indicating that concomitant loss of these two tumor suppressors contributes to tumorigenesis via mechanisms that are only partially interrelated. We generated a Msh6-/-;p53+/- mouse model which succumbed to malignant disease at an accelerated rate and with a tumor spectrum distinct from both Msh6-/- and p53+/- models. Alteration of tumor phenotype in the Msh6-/-;p53+/- mice included a marked increase in microsatellite instability that was associated with loss of heterozygosity of the remaining p53 allele. Also, genetic instability was inversely correlated with survival. This manuscript marks the first in vivo investigation into the association between Msh6 and p53, and their combined role in the suppression of spontaneous tumorigenesis, cell survival and genomic stability. Our results support the hypothesis that p53 and Msh6 are functionally interrelated and that, with concomitant mutation, these tumor suppressors act together to accelerate tumorigenesis.
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Affiliation(s)
- Leah C Young
- Department of Medical Genetics, University of Alberta, Edmonton, Alberta T6G 2H7, Canada
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36
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Jenkins MA, Southey MC, Giles GG, Hopper JL. Rationale for, and approach to, studying modifiers of risk in persons with a genetic predisposition to colorectal cancer. Curr Oncol Rep 2007; 9:202-7. [PMID: 17430691 DOI: 10.1007/s11912-007-0022-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
We address the issue of modifiers of risk for persons who are, on average, at high risk of colorectal cancer due to carrying germline genetic mutations. We discuss how to estimate risk and assess modifiers using data from mutation-carrying families. A critical analytical issue is the adjustment for how families have been sampled (ascertainment). Only a few published studies have made appropriate adjustments and have mostly reported lifetime risks of less than 50%. Incomplete penetrance and differences in risk by subcategories are consistent with the existence of genetic and/or environmental risk -modifiers. Data from large cohorts of carriers are required to study such modifiers with precision.
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Affiliation(s)
- Mark A Jenkins
- Centre for Molecular, Environmental, Genetic and Analytic Epidemiology, The University of Melbourne, Carlton, Victoria 3053, Australia
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Cahill DP, Levine KK, Betensky RA, Codd PJ, Romany CA, Reavie LB, Batchelor TT, Futreal PA, Stratton MR, Curry WT, Iafrate AJ, Louis DN. Loss of the mismatch repair protein MSH6 in human glioblastomas is associated with tumor progression during temozolomide treatment. Clin Cancer Res 2007; 13:2038-45. [PMID: 17404084 PMCID: PMC2873832 DOI: 10.1158/1078-0432.ccr-06-2149] [Citation(s) in RCA: 311] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Glioblastomas are treated by surgical resection followed by radiotherapy [X-ray therapy (XRT)] and the alkylating chemotherapeutic agent temozolomide. Recently, inactivating mutations in the mismatch repair gene MSH6 were identified in two glioblastomas recurrent post-temozolomide. Because mismatch repair pathway inactivation is a known mediator of alkylator resistance in vitro, these findings suggested that MSH6 inactivation was causally linked to these two recurrences. However, the extent of involvement of MSH6 in glioblastoma is unknown. We sought to determine the overall frequency and clinical relevance of MSH6 alterations in glioblastomas. EXPERIMENTAL DESIGN The MSH6 gene was sequenced in 54 glioblastomas. MSH6 and O(6)-methylguanine methyltransferase (MGMT) immunohistochemistry was systematically scored in a panel of 46 clinically well-characterized glioblastomas, and the corresponding patient response to treatment evaluated. RESULTS MSH6 mutation was not observed in any pretreatment glioblastoma (0 of 40), whereas 3 of 14 recurrent cases had somatic mutations (P = 0.015). MSH6 protein expression was detected in all pretreatment (17 of 17) cases examined but, notably, expression was lost in 7 of 17 (41%) recurrences from matched post-XRT + temozolomide cases (P = 0.016). Loss of MSH6 was not associated with O(6)-methylguanine methyltransferase status. Measurements of in vivo tumor growth using three-dimensional reconstructed magnetic resonance imaging showed that MSH6-negative glioblastomas had a markedly increased rate of growth while under temozolomide treatment (3.17 versus 0.04 cc/mo for MSH6-positive tumors; P = 0.020). CONCLUSIONS Loss of MSH6 occurs in a subset of post-XRT + temozolomide glioblastoma recurrences and is associated with tumor progression during temozolomide treatment, mirroring the alkylator resistance conferred by MSH6 inactivation in vitro. MSH6 deficiency may therefore contribute to the emergence of recurrent glioblastomas during temozolomide treatment.
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Affiliation(s)
- Daniel P Cahill
- Molecular Pathology Unit, Neurosurgical Service, Brain Tumor Center, and Center for Cancer Research, Massachusetts General Hospital and Harvard Medical School, Boston, MA 02114, USA
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Rationale for, and approach to, studying modifiers of risk in persons with a genetic predisposition to colorectal cancer. CURRENT COLORECTAL CANCER REPORTS 2006. [DOI: 10.1007/s11888-006-0019-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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39
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Chen S, Wang W, Lee S, Nafa K, Lee J, Romans K, Watson P, Gruber SB, Euhus D, Kinzler KW, Jass J, Gallinger S, Lindor NM, Casey G, Ellis N, Giardiello FM, Offit K, Parmigiani G. Prediction of germline mutations and cancer risk in the Lynch syndrome. JAMA 2006; 296:1479-87. [PMID: 17003396 PMCID: PMC2538673 DOI: 10.1001/jama.296.12.1479] [Citation(s) in RCA: 260] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
CONTEXT Identifying families at high risk for the Lynch syndrome (ie, hereditary nonpolyposis colorectal cancer) is critical for both genetic counseling and cancer prevention. Current clinical guidelines are effective but limited by applicability and cost. OBJECTIVE To develop and validate a genetic counseling and risk prediction tool that estimates the probability of carrying a deleterious mutation in mismatch repair genes MLH1, MSH2, or MSH6 and the probability of developing colorectal or endometrial cancer. DESIGN, SETTING, AND PATIENTS External validation of the MMRpro model was conducted on 279 individuals from 226 clinic-based families in the United States, Canada, and Australia (referred between 1993-2005) by comparing model predictions with results of highly sensitive germline mutation detection techniques. MMRpro models the autosomal dominant inheritance of mismatch repair mutations, with parameters based on meta-analyses of the penetrance and prevalence of mutations and of the predictive values of tumor characteristics. The model's prediction is tailored to each individual's detailed family history information on colorectal and endometrial cancer and to tumor characteristics including microsatellite instability. MAIN OUTCOME MEASURE Ability of MMRpro to correctly predict mutation carrier status, as measured by operating characteristics, calibration, and overall accuracy. RESULTS In the independent validation, MMRpro provided a concordance index of 0.83 (95% confidence interval, 0.78-0.88) and a ratio of observed to predicted cases of 0.94 (95% confidence interval, 0.84-1.05). This results in higher accuracy than existing alternatives and current clinical guidelines. CONCLUSIONS MMRpro is a broadly applicable, accurate prediction model that can contribute to current screening and genetic counseling practices in a high-risk population. It is more sensitive and more specific than existing clinical guidelines for identifying individuals who may benefit from MMR germline testing. It is applicable to individuals for whom tumor samples are not available and to individuals in whom germline testing finds no mutation.
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Affiliation(s)
- Sining Chen
- Department of Environmental Health Sciences, Johns Hopkins Bloomberg School of Public Health, Baltimore, Md 21205, USA.
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40
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Taylor NP, Powell MA, Gibb RK, Rader JS, Huettner PC, Thibodeau SN, Mutch DG, Goodfellow PJ. MLH3 Mutation in Endometrial Cancer. Cancer Res 2006; 66:7502-8. [PMID: 16885347 DOI: 10.1158/0008-5472.can-06-0248] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
MLH3 is a recently described member of the DNA mismatch repair gene family. Based on its interaction with the MutL homologue MLH1, it was postulated that MLH3 might play a role in tumorigenesis. Germ line and somatic mutations in MLH3 have been identified in a small fraction of colorectal cancers, but the role of MLH3 in colorectal cancer tumorigenesis remains controversial. We investigated MLH3's role in endometrial tumorigenesis through analysis of tumor and germ line DNA from 57 endometrial cancer patients who were at increased risk for having inherited cancer susceptibility. Patients with known MSH2 or MSH6 mutations were excluded as well as those who had MLH1-methylated tumors. Sixteen different variants were identified by single-strand conformational variant analysis. Of the 12 missense changes identified, three were somatic mutations. One patient had a germ line missense variant and loss of heterozygosity (LOH) in her tumor specimen. There was no evidence of MLH3 promoter methylation based on combined bisulfite restriction analysis. The identification of inherited missense variants, somatic missense mutations (present in 3 of 57 tumors), and LOH in the tumor from a patient with a germ line missense change suggest a role for MLH3 in endometrial tumorigenesis.
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Affiliation(s)
- Nicholas P Taylor
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, Washington University School of Medicine, 4911 Barnes-Jewish Hospital Plaza, St. Louis, MO 63110, USA.
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41
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Cederquist K, Emanuelsson M, Wiklund F, Golovleva I, Palmqvist R, Grönberg H. Two Swedish founder MSH6 mutations, one nonsense and one missense, conferring high cumulative risk of Lynch syndrome. Clin Genet 2006; 68:533-41. [PMID: 16283884 DOI: 10.1111/j.1399-0004.2005.00537.x] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Lynch syndrome, or hereditary non-polyposis colorectal cancer (HNPCC), is a cancer susceptibility syndrome caused by germline mutations in mismatch-repair genes, predominantly MLH1, MSH2 and MSH6. A majority of the mutations reported are truncating, but for MSH6, missense mutations constitute over one third. Few have been proven pathogenic in functional studies or shown to segregate in families. In this study, we show segregation of the putative pathogenic MSH6 missense mutation c.1346T>C p.Leu449Pro with microsatellite instability-high Lynch syndrome-related tumours lacking MSH6 expression in a large 17th century pedigree. Another large family with the MSH6 nonsense c.2931C>G, p.Tyr977X mutation is similar in tumour spectra, age of onset and cumulative risk. These MSH6 families, despite their late age of onset, have a high lifetime risk of all Lynch syndrome-related cancers, significantly higher in women (89% by age 80) than in men (69%). The gender differences are in part explained by high endometrial (70%) and ovarian (33%) cancer risks added upon the high colorectal cancer risk (60%). The several occurrences of breast cancer are not due to the MSH6 mutations. These findings are of great importance for counselling, management and surveillance of families with MSH6 mutations.
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Affiliation(s)
- K Cederquist
- Medical and Clinical Genetics, Department of Medical Biosciences, Umea University, Sweden.
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42
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Abstract
Since the discovery of the major human genes with DNA mismatch repair (MMR) function in 1993-1995, mutations in four, MSH2, MLH1, MSH6, and PMS2, have been convincingly linked to susceptibility of hereditary nonpolyposis colorectal cancer (HNPCC)/Lynch syndrome. Among these, PMS2 mutations are associated with diverse clinical features, including those of the Turcot syndrome. Two additional MMR genes, MLH3 and PMS1, have also been proposed to play a role in Lynch syndrome predisposition, but the clinical significance of mutations in these genes is less clear. According to the database maintained by the International Collaborative Group on Hereditary Nonpolyposis Colorectal Cancer (ICG-HNPCC), current InSiGHT (International Society for Gastrointestinal Hereditary Tumors), approximately 500 different HNPCC-associated MMR gene mutations are known that primarily involve MLH1 (approximately 50%), MSH2 (approximately 40%), and MSH6 (approximately 10%). Examination of HNPCC/Lynch syndrome-associated MMR genes and their mutations has revealed several other important functions for their protein products beyond postreplicative mismatch repair as well as many alternative mechanisms of pathogenicity. Despite these advances, much is yet to be learned about the molecular basis of correlations between genetic changes and clinical features of the disease.
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Affiliation(s)
- Päivi Peltomäki
- Department of Medical Genetics, Biomedicum Helsinki, University of Helsinki, P.O. Box 63, Haartmaninkatu 8, 00014, Finland.
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Gologan A, Krasinskas A, Hunt J, Thull DL, Farkas L, Sepulveda AR. Performance of the Revised Bethesda Guidelines for Identification of Colorectal Carcinomas With a High Level of Microsatellite Instability. Arch Pathol Lab Med 2005; 129:1390-7. [PMID: 16253017 DOI: 10.5858/2005-129-1390-potrbg] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
AbstractContext.—Criteria for microsatellite instability (MSI) testing to rule out hereditary nonpolyposis colorectal cancer were recently revised and include parameters such as age and specific histologic features that can be identified by the pathologist, triggering reflex MSI testing.Objective.—To review the performance of the revised Bethesda guidelines to identify MSI-positive colorectal cancers.Design.—Seventy-five patients with colorectal cancer were included; 68 patients younger than 50 years and 7 patients between 50 and 60 years were selected based on histopathologic criteria. Microsatellite instability testing with the National Cancer Institute–recommended panel and immunohistochemistry for hMLH1 and hMSH2 were performed. Tumors were classified into microsatellite instability high (MSI-H), low (MSI-L), or stable (MSS) categories.Results.—Overall, 17 (23%) of 75 colorectal cancer cases were classified as MSI-H, including 13 patients younger than 50 years and 4 patients between 50 and 60 years. Among the MSI-H tumors, 10 (59%) were characterized by loss of hMLH1 and 6 (35%) were hMSH2 negative. Histologic features suggestive of MSI-H phenotype were present in 80% of MSI-H and 35% of MSS/MSI-L tumors. The number of positive lymph nodes was higher in MSS/MSI-L adenocarcinomas (P = .04).Conclusions.—By selecting for age and histologic features, we detected MSI-H tumors in approximately one quarter of colorectal cancer cases meeting the revised Bethesda guidelines and identified 17 MSI-H cases, whereas only 8 would have been recognized by the prior guidelines. These data indicate that reflex testing requested by pathologists based on the revised Bethesda guidelines increases the detection of MSI-H and potential hereditary nonpolyposis colorectal cancer cases.
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Affiliation(s)
- Adrian Gologan
- Department of Pathology, University of Pittsburgh, Pittsburgh, PA, USA
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44
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Sánchez de Abajo A, de la Hoya M, Tosar A, Godino J, Fernández JM, Asenjo JL, Villamil BP, Segura PP, Diaz-Rubio E, Caldes T. Low prevalence of germline hMSH6 mutations in colorectal cancer families from Spain. World J Gastroenterol 2005; 11:5770-6. [PMID: 16270383 PMCID: PMC4479674 DOI: 10.3748/wjg.v11.i37.5770] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
AIM: To investigate the prevalence and penetrance of hMSH6 mutations in Spanish HNPCC families that was negative for mutation in hMLH1 or hMSH2.
METHODS: We used PCR-based DGGE assay and direct sequencing to screen for hMSH6 gene in 91 HNPCC families.
RESULTS: we have identified 10 families with germ-line mutations in the DNA sequence. These mutations included two intronic variation, three missense mutation, one nonsense mutation, and four silent mutations. Among the 10 germ-line mutations identified in the Spanish cohort, 8 were novel, perhaps, suggesting different mutational spectra in the Spanish population. Detailed pedigrees were constructed for the three families with a possible pathogenic hMSH6 mutation. The two silent mutations H388H and L758L, detected in a person affected of colorectal cancer at age 29, produce loss of the wild-type allele in the tumor sample. Immunohistochemical analysis showed that expression of MSH6 protein was lost only in the tumors from the carriers of V878A and Q263X mutations.
CONCLUSION: Altogether, our results indicate that disease-causing germ-line mutations of hMSH6 are very less frequent in Spanish HNPCC families.
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Affiliation(s)
- Ana Sánchez de Abajo
- Laboratorio de Oncología Molecular, Hospital Clinico San Carlos, Martin Lagos s/n, Madrid 28040, Spain
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45
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Abstract
The principal Mendelian disorders predisposing to colorectal cancer are familial adenomatous polyposis (FAP) and hereditary nonpolyposis colorectal cancer (HNPCC). FAP is due to mutations in the APC gene. HNPCC is due to a mutation in one of at least five mismatch repair genes. Identification of individuals with these conditions is important because colon cancer will occur in approximately 80% and onset is early. For FAP, protein truncation testing will identify the vast majority of mutations. For HNPCC, 80%-95% can be identified by microsatellite instability testing. A current U.S. study reports that 12% of consecutive colorectal cancers have high microsatellite instability and that, of this 12%, 25% have detectable mutations of MLH1, MSH2, or MSH6. Potential benefits of identification include improved compliance with recommended surveillance, early detection of polyps, reduction in cancer mortality, offering of testing to relatives, and reassurance for relatives found to be negative with attendant savings in the time and expense of surveillance.
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Affiliation(s)
- Peter T Rowley
- Department of Medicine and Division of Genetics, University of Rochester, Rochester, New York 14642, USA.
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46
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Green RC, McLaughlin JR, Younghusband HB. SISE matters: the Sum of Information on Seventy-yr-old Equivalents measures pedigree information content when assessing the risk of HNPCC in a family. Fam Cancer 2005; 4:169-75. [PMID: 15951969 DOI: 10.1007/s10689-004-7251-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2004] [Accepted: 12/01/2004] [Indexed: 11/25/2022]
Abstract
Hereditary non-polyposis colon cancer (HNPCC) is a significant cause of colorectal and other malignancies. Due to the lack of features that reliably differentiate between a sporadic case and an inherited case of colon cancer, it is likely that HNPCC is under reported. The diagnosis of HNPCC relies heavily on finding multiple cases of colorectal or other specific cancers within a family. In the absence of a significant family history, a diagnosis of HNPCC is seldom considered. We postulate that small kinships--or, more specifically, kinships with a low information content--are more likely to be designated as having a low risk of an inherited cancer predisposition than are large kinships. This has the potential to exacerbate the under-diagnosis of HNPCC in small families, leading to inadequate treatment, follow-up and family counselling. We have developed an objective measure of the information content of individual pedigrees called the Sum of Information on Seventy-yr-old Equivalents (SISE) coefficient. The SISE coefficient is a function of the number of relatives in a kinship and their relationship to the proband, of their ages and of the age-dependent penetrance of HNPCC mutations. A population-based series of colorectal cancer cases was assessed, by currently accepted methods, for the likelihood of there being an HNPCC mutation segregating in each family. We observed that families with a low SISE coefficient were significantly more likely to be designated at low risk of HNPCC (P< or =0.001). Using a cumulative binomial distribution function, we estimated the likelihood of observing multiple cancers in families of different SISE coefficients.
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Affiliation(s)
- R C Green
- Faculty of Medicine, Memorial University, St. John's, Newfoundland, A1B 3V6 Canada.
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47
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Devlin LA, Price JH, Morrison PJ. Hereditary non-polyposis colon cancer. THE ULSTER MEDICAL JOURNAL 2005; 74:14-21. [PMID: 16025587 PMCID: PMC2475474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- L A Devlin
- Department of Medical Genetics, Belfast City Hospital, Lisburn Road, Belfast
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48
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Abstract
The genes associated with each of the inherited syndromes of colon cancer have now been identified, and genetic testing is available for diagnosis. These syndromes include familial adenomatous polyposis, hereditary nonpolyposis colorectal cancer, Peutz-Jeghers syndrome, juvenile polyposis syndrome, and, possibly, Cowden's syndrome. Clinical genetic testing approaches have been developed for each of these syndromes and are now a part of accepted clinical care. Disease-causing mutations can be found in the majority of families affected with one of the inherited syndromes, and, most importantly, once a mutation is found in an index case of the family, relatives can be tested for the presence or absence of that mutation with near 100% accuracy. Cancer screening and management in syndrome families is then based on the results of genetic testing. For the physician to order and properly interpret genetic tests, a basic understanding of the types of mutations that lead to inherited disease and the methods for detecting them is vital. These issues will be presented. Additional clinical issues somewhat unique to genetic testing include genetic counseling and informed consent for genetic testing, both of which will also be reviewed. Often the most difficult aspect of genetic testing is deciding which patients and families should undergo the testing. Furthermore, this issue is quite specific for each of the syndromes. Thus, following presentation of general principles of selection for genetic testing, a detailed approach for identifying persons who should undergo testing for each of the individual syndromes will be given, together with relevant descriptions of the syndromes. Finally, the ongoing work to discover new and possibly more common but less penetrant colon cancer susceptibility genes that cause common familial colon cancer will be presented.
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Affiliation(s)
- Randall Burt
- Huntsman Cancer Institute at University of Utah, Salt Lake City, Utah 84112, USA.
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49
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Lindor NM, Rabe K, Petersen GM, Haile R, Casey G, Baron J, Gallinger S, Bapat B, Aronson M, Hopper J, Jass J, LeMarchand L, Grove J, Potter J, Newcomb P, Terdiman JP, Conrad P, Moslein G, Goldberg R, Ziogas A, Anton-Culver H, de Andrade M, Siegmund K, Thibodeau SN, Boardman LA, Seminara D. Lower cancer incidence in Amsterdam-I criteria families without mismatch repair deficiency: familial colorectal cancer type X. JAMA 2005; 293:1979-85. [PMID: 15855431 PMCID: PMC2933042 DOI: 10.1001/jama.293.16.1979] [Citation(s) in RCA: 450] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
CONTEXT Approximately 60% of families that meet the Amsterdam-I criteria (AC-I) for hereditary nonpolyposis colorectal cancer (HNPCC) have a hereditary abnormality in a DNA mismatch repair (MMR) gene. Cancer incidence in AC-I families with MMR gene mutations is reported to be very high, but cancer incidence for individuals in AC-I families with no evidence of an MMR defect is unknown. OBJECTIVE To determine if cancer risks in AC-I families with no apparent deficiency in DNA MMR are different from cancer risks in AC-I families with DNA MMR abnormalities. DESIGN, SETTING, AND PARTICIPANTS Identification (1997-2001) of 161 AC-I pedigrees from multiple population- and clinic-based sources in North America and Germany, with families grouped into those with (group A) or without (group B) MMR deficiency by tumor testing. A total of 3422 relatives were included in the analyses. MAIN OUTCOME MEASURES Cancer incidence in groups A and B (excluding the 3 affected members used to define each pedigree as AC-I) and computed age- and sex-adjusted standardized incidence ratios (SIRs) using Surveillance, Epidemiology, and End Results data. RESULTS Group A families from both population- and clinic-based series showed increased incidence of the HNPCC-related cancers. Group B families showed increased incidence only for colorectal cancer (SIR, 2.3; 95% confidence interval, 1.7-3.0) and to a lesser extent than group A (SIR, 6.1; 95% confidence interval, 5.2-7.2) (P<.001). CONCLUSIONS Families who fulfill AC-I criteria but who have no evidence of a DNA MMR defect do not share the same cancer incidence as families with HNPCC-Lynch syndrome (ie, hereditary MMR deficiency). Relatives in such families have a lower incidence of colorectal cancer than those in families with HNPCC-Lynch syndrome, and incidence may not be increased for other cancers. These families should not be described or counseled as having HNPCC-Lynch syndrome. To facilitate distinguishing these entities, the designation of "familial colorectal cancer type X" is suggested to describe this type of familial aggregation of colorectal cancer.
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Gologan A, Sepulveda AR. Microsatellite Instability and DNA Mismatch Repair Deficiency Testing in Hereditary and Sporadic Gastrointestinal Cancers. Clin Lab Med 2005; 25:179-96. [PMID: 15749237 DOI: 10.1016/j.cll.2004.12.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reference cancers associated with DNA mismatch repair (MMR)deficiency are the adenocarcinomas of patients with hereditary nonpolyposis colorectal cancer, also known as Lynch syndrome. Sporadic gastrointestinal (GI) carcinomas, most commonly colorectal and gastric carcinomas, may also be associated with deficiencies of DNA mismatch repair. Deficiency in cellular MMR leads to wide-spread mutagenesis and neoplastic development and progression. An important diagnostic feature of MMR-deficient tumors is the high rate of mutations that accumulate in repetitive nucleotide regions, and these mutations are known as microsatellite instability(MSI). A standard panel of markers to test for MSI in tumors has been recommended and efficiently separates tumors into those with high, low, or no microsatellite instability (MSI-H, MSI-L, or MSS). Tumors characterized by MSI-H characteristically show loss of one of the main DNA MMR proteins, mLH1 or MSH2, and rarely MSH6 and PMS2, detected by immunohistochemistry (IHC). The combination of MSI testing and IHC for MMR proteins in tumors tissues is used to identify underlying DNA MMR deficiency andis clinically relevant screen patients who might have hereditary non-polyposis colorectal cancer for DNA repair gene germline testing. Increasing evidence demonstrates that tumors with a positive MSI status have lower lymph node metastases burden, and these patients have an overall improved survival, suggesting that the MSI and MMR status may contribute to decision making regarding treatment approaches. Updated guidelines for MSI and IHC for DNAMMR testing, and the biological and potential clinical implications of MMR deficiency and microsatellite instability in GI polyps and cancers are reviewed.
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Affiliation(s)
- Adrian Gologan
- Department of Pathology, University of Pittsburgh, PUH-A610, 100 Lothrop Street, Pittsburgh, PA 15213-2582, USA
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