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The British Journal of Surgery May 2021Lynch syndrome is the most common genetic predisposition for hereditary cancer but remains underdiagnosed. Large prospective observational studies have recently...
BACKGROUND
Lynch syndrome is the most common genetic predisposition for hereditary cancer but remains underdiagnosed. Large prospective observational studies have recently increased understanding of the effectiveness of colonoscopic surveillance and the heterogeneity of cancer risk between genotypes. The need for gene- and gender-specific guidelines has been acknowledged.
METHODS
The European Hereditary Tumour Group (EHTG) and European Society of Coloproctology (ESCP) developed a multidisciplinary working group consisting of surgeons, clinical and molecular geneticists, pathologists, epidemiologists, gastroenterologists, and patient representation to conduct a graded evidence review. The previous Mallorca guideline format was used to revise the clinical guidance. Consensus for the guidance statements was acquired by three Delphi voting rounds.
RESULTS
Recommendations for clinical and molecular identification of Lynch syndrome, surgical and endoscopic management of Lynch syndrome-associated colorectal cancer, and preventive measures for cancer were produced. The emphasis was on surgical and gastroenterological aspects of the cancer spectrum. Manchester consensus guidelines for gynaecological management were endorsed. Executive and layperson summaries were provided.
CONCLUSION
The recommendations from the EHTG and ESCP for identification of patients with Lynch syndrome, colorectal surveillance, surgical management of colorectal cancer, lifestyle and chemoprevention in Lynch syndrome that reached a consensus (at least 80 per cent) are presented.
Topics: Anti-Inflammatory Agents, Non-Steroidal; Aspirin; Chemoprevention; Colonoscopy; Colorectal Neoplasms, Hereditary Nonpolyposis; Delphi Technique; Digestive System Surgical Procedures; Early Detection of Cancer; Female; Genetic Carrier Screening; Genetic Testing; Genital Neoplasms, Female; Humans; Life Style; Prophylactic Surgical Procedures
PubMed: 34043773
DOI: 10.1002/bjs.11902 -
Annals of Oncology : Official Journal... Aug 2019Cancers with a defective DNA mismatch repair (dMMR) system contain thousands of mutations most frequently located in monomorphic microsatellites and are thereby defined...
ESMO recommendations on microsatellite instability testing for immunotherapy in cancer, and its relationship with PD-1/PD-L1 expression and tumour mutational burden: a systematic review-based approach.
BACKGROUND
Cancers with a defective DNA mismatch repair (dMMR) system contain thousands of mutations most frequently located in monomorphic microsatellites and are thereby defined as having microsatellite instability (MSI). Therefore, MSI is a marker of dMMR. MSI/dMMR can be identified using immunohistochemistry to detect loss of MMR proteins and/or molecular tests to show microsatellite alterations. Together with tumour mutational burden (TMB) and PD-1/PD-L1 expression, it plays a role as a predictive biomarker for immunotherapy.
METHODS
To define best practices to implement the detection of dMMR tumours in clinical practice, the ESMO Translational Research and Precision Medicine Working Group launched a collaborative project, based on a systematic review-approach, to generate consensus recommendations on the: (i) definitions related to the concept of MSI/dMMR; (ii) methods of MSI/dMMR testing and (iii) relationships between MSI, TMB and PD-1/PD-L1 expression.
RESULTS
The MSI-related definitions, for which a consensus frame-work was used to establish definitions, included: 'microsatellites', 'MSI', 'DNA mismatch repair' and 'features of MSI tumour'. This consensus also provides recommendations on MSI testing; immunohistochemistry for the mismatch repair proteins MLH1, MSH2, MSH6 and PMS2 represents the first action to assess MSI/dMMR (consensus with strong agreement); the second method of MSI/dMMR testing is represented by polymerase chain reaction (PCR)-based assessment of microsatellite alterations using five microsatellite markers including at least BAT-25 and BAT-26 (strong agreement). Next-generation sequencing, coupling MSI and TMB analysis, may represent a decisive tool for selecting patients for immunotherapy, for common or rare cancers not belonging to the spectrum of Lynch syndrome (very strong agreement). The relationships between MSI, TMB and PD-1/PD-L1 expression are complex, and differ according to tumour types.
CONCLUSIONS
This ESMO initiative is a response to the urgent questions raised by the growing success of immunotherapy and provides also important insights on the relationships between MSI, TMB and PD-1/PD-L1.
Topics: Antineoplastic Agents, Immunological; B7-H1 Antigen; Biomarkers, Tumor; DNA Mismatch Repair; DNA Mutational Analysis; European Union; Genetic Testing; High-Throughput Nucleotide Sequencing; Humans; Immunohistochemistry; Medical Oncology; Microsatellite Instability; Mutation; Neoplasms; Patient Selection; Practice Guidelines as Topic; Programmed Cell Death 1 Receptor; Societies, Medical
PubMed: 31056702
DOI: 10.1093/annonc/mdz116 -
World Journal of Urology Mar 2017Upper-tract urothelial carcinoma (UTUC) is a relatively uncommon disease with limited available evidence on specific topics. The purpose of this article was to review... (Review)
Review
PURPOSE
Upper-tract urothelial carcinoma (UTUC) is a relatively uncommon disease with limited available evidence on specific topics. The purpose of this article was to review the previous literature to summarize the current knowledge about UTUC epidemiology, diagnosis, preoperative evaluation and prognostic assessment.
METHODS
Using MEDLINE, a non-systematic review was performed including articles between January 2000 and February 2016. English language original articles, reviews and editorials were selected based on their clinical relevance.
RESULTS
UTUC accounts for 5-10 % of all urothelial cancers, with an increasing incidence. UTUC and bladder cancer share some common risk factors, even if they are two different entities regarding practical, biological and clinical characteristics. Aristolochic acid plays an important role in UTUC pathogenesis in certain regions. It is further estimated that approximately 10 % of UTUC are part of the hereditary non-polyposis colorectal cancer spectrum disease. UTUC diagnosis remains mainly based on imaging and endoscopy, but development of new technologies is rapidly changing the diagnosis algorithm. To help the decision-making process regarding surgical treatment, extent of lymphadenectomy and selection of neoadjuvant systemic therapies, predictive tools based on preoperative patient and tumor characteristics have been developed.
CONCLUSIONS
Awareness regarding epidemiology, diagnosis, preoperative evaluation and prognostic assessment changes is essential to correctly diagnose and manage UTUC patients, thereby potentially improving their outcomes.
Topics: Aristolochic Acids; Carcinoma, Transitional Cell; Colorectal Neoplasms, Hereditary Nonpolyposis; Humans; Kidney Neoplasms; Kidney Pelvis; Lymph Node Excision; Neoadjuvant Therapy; Preoperative Care; Prognosis; Risk Factors; Ureteral Neoplasms; Ureteroscopy; Urinary Bladder Neoplasms
PubMed: 27604375
DOI: 10.1007/s00345-016-1928-x -
Clinical Gastroenterology and... Mar 2022Lynch syndrome is a form of hereditary colorectal cancer (CRC) caused by pathogenic germline variants (PV) in DNA mismatch repair (MMR) genes. Currently, many Western... (Meta-Analysis)
Meta-Analysis
BACKGROUND & AIMS
Lynch syndrome is a form of hereditary colorectal cancer (CRC) caused by pathogenic germline variants (PV) in DNA mismatch repair (MMR) genes. Currently, many Western countries perform universal immunohistochemistry testing on CRC to increase the identification of Lynch syndrome patients and their relatives. For a clear understanding of health benefits and costs, data on its outcomes are required: proportions of Lynch syndrome, sporadic MMR-deficient (MMRd) cases, and unexplained MMRd cases.
METHODS
Ovid Medline, Embase, and Cochrane CENTRAL were searched for studies reporting on universal MMR immunohistochemistry, followed by MMR germline analysis, until March 20, 2020. Proportions were calculated, subgroup analyses were performed based on age and diagnostics used, and random effects meta-analyses were conducted. Quality was assessed using the Joanna Briggs Critical Appraisal Tool for Prevalence Studies.
RESULTS
Of 2723 identified articles, 56 studies covering 58,580 CRCs were included. In 6.22% (95% CI, 5.08%-7.61%; I = 96%) MMRd was identified. MMR germline PV was present in 2.00% (95% CI, 1.59%-2.50%; I = 92%), ranging from 1.80% to 7.27% based on completeness of diagnostics and age restriction. Immunohistochemistry outcomes were missing in 11.81%, and germline testing was performed in 76.30% of eligible patients. In 7 studies, including 6848 CRCs completing all diagnostic stages, germline PV and biallelic somatic MMR inactivation were found in 3.01% and 1.75%, respectively; 0.61% remained unexplained MMRd.
CONCLUSIONS
Age, completeness, and type of diagnostics affect the percentage of MMR PV and unexplained MMRd percentages. Complete diagnostics explain almost all MMRd CRCs, reducing the amount of subsequent multigene panel testing. This contributes to optimizing testing and surveillance in MMRd CRC patients and relatives.
Topics: Colorectal Neoplasms; Colorectal Neoplasms, Hereditary Nonpolyposis; DNA Mismatch Repair; Humans; Immunohistochemistry
PubMed: 33887476
DOI: 10.1016/j.cgh.2021.04.021 -
Health Technology Assessment... Sep 2014Lynch syndrome (LS) is an inherited autosomal dominant disorder characterised by an increased risk of colorectal cancer (CRC) and other cancers, and caused by mutations... (Review)
Review
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.
Topics: Aged; Colorectal Neoplasms, Hereditary Nonpolyposis; Cost-Benefit Analysis; Genetic Testing; Humans; Middle Aged
PubMed: 25244061
DOI: 10.3310/hta18580 -
Genetics in Medicine : Official Journal... May 2022Lynch syndrome (LS) is the most common hereditary colorectal cancer (CRC) syndrome, with an estimated prevalence of 2% to 3% of CRC. A prevalence study is needed to... (Meta-Analysis)
Meta-Analysis Review
PURPOSE
Lynch syndrome (LS) is the most common hereditary colorectal cancer (CRC) syndrome, with an estimated prevalence of 2% to 3% of CRC. A prevalence study is needed to provide accurate estimates of the true prevalence of LS.
METHODS
MEDLINE (Ovid), Embase, and Web of Science were searched. Prevalence was calculated by random effects meta-analysis models. I score was used to assess heterogeneity across studies. Meta-regression was performed for between-study variance.
RESULTS
A total of 51 studies were included in this review. The overall pooled yield of LS screening was 2.2% based on all methods of detection. Studies performing germline tests on all participants with CRC reported higher prevalence (5.1%) as opposed to studies only performing germline tests on participants with tumors with mismatch repair deficiency (1.6%) or microsatellite instability (1.1%). Selected cohorts of CRC had a higher prevalence of germline LS diagnoses.
CONCLUSION
LS prevalence across multiple ethnic, geographic, and clinical populations is remarkably similar. Universal germline testing of patients presenting with cancer identifies that most CRCs are attributed to LS. Young patients presenting with CRC and those who fulfill criteria for a familial risk provide the highest returns for LS identification. Our study supports the universal germline CRC screening for LS.
Topics: Colorectal Neoplasms; Colorectal Neoplasms, Hereditary Nonpolyposis; DNA Mismatch Repair; Humans; Microsatellite Instability; Prevalence
PubMed: 35177335
DOI: 10.1016/j.gim.2022.01.014 -
Cancers Jan 2023Background: The association between Lynch syndrome (LS) and a higher risk of upper tract urothelial carcinoma is well established, but its effect on the risk of bladder... (Review)
Review
Background: The association between Lynch syndrome (LS) and a higher risk of upper tract urothelial carcinoma is well established, but its effect on the risk of bladder and kidney cancers remains controversial. This review aimed to compare the relative risk (RR) of bladder and kidney cancer in confirmed LS germline mutation carriers compared to the general population. Methods: Medline, Embase, Cochrane Central, and Google Scholar were searched on 14 July 2022 for studies published in English that reported on the rates of urological cancer in adults with confirmed LS germline mutation. The quality of included studies was assessed using Cochrane’s tool to evaluate risk of bias in cohort studies. Random effects meta-analysis estimated the pooled relative risk of bladder and kidney cancer in LS carriers compared to the general population. The quality of the overall evidence was evaluated using GRADE. Results: Of the 1839 records identified, 5 studies involving 7120 participants from 3 continents were included. Overall, LS carriers had a statistically significantly higher RR of developing bladder cancer (RR: 7.48, 95% CI: 3.70, 15.13) and kidney cancer (RR: 3.97, 95% CI: 1.23, 12.81) compared to unaffected participants (p < 0.01). The quality of the evidence was assessed as “low” due to the inclusion of cohort studies, the substantial heterogeneity, and moderate-to-high risk of bias. Conclusion: Lynch syndrome is associated with a significant increase in the relative risk of kidney and bladder cancer. Clinicians should adopt a lower threshold for germline mutation genetic testing in individuals who present with bladder cancer. Further studies evaluating the role and cost-effectiveness of novel urine-based laboratory tests are needed. High-quality studies in histologically proven renal cell carcinoma and their underlying germline mutations are necessary to strengthen the association with LS.
PubMed: 36672455
DOI: 10.3390/cancers15020506 -
Journal of Cancer Research and Clinical... Jan 2023Lynch-like syndrome (LLS) tumors have similar clinicopathological features to Lynch syndrome (LS) tumors but have no identifiable pathogenic germline mismatch repair...
BACKGROUND
Lynch-like syndrome (LLS) tumors have similar clinicopathological features to Lynch syndrome (LS) tumors but have no identifiable pathogenic germline mismatch repair gene variant. However, cancer risks in LLS patients and first-degree relatives (FDRs) are not well defined.
METHODS
To clarify LLS-associated cancer risks, a systematic review of all studies examining all cancer risks in LLS was performed. Searching of Medline, Embase, Pubmed, Cochrane and CINAHL databases and reference/citation checking identified relevant studies published between January 1, 1980 and February 11, 2021. Joanna Briggs Institute Appraisal Tools assessed the risk of bias.
RESULTS
Six studies (five cohort/one cross-sectional) were eligible for study inclusion. One study found no difference in colorectal cancer (CRC) incidence between LLS and LS patients or CRC risks at aged 70 years. Three studies found CRC incidence in LLS FDRs was higher than the general population but lower than LS FDRs. Two studies showed no difference in CRC diagnosis age between LLS patients and LS patients. Endometrial cancer risks in LLS patients were higher than the general population but lower than LS patients.
CONCLUSION
Evidence of elevated CRC risks in LLS patients and FDRs supports increased colonoscopy surveillance strategies for LLS patients and FDRs in line with current recommendations for LS. Due to heterogeneity amongst LLS populations, extended intervals between screening may be advised for low-risk families. Studies to resolve the molecular characterization and definition of LLS are needed to clarify cancer risks associated with LLS which in turn may individualize surveillance strategies for LLS patients and families.
Topics: Female; Humans; Cross-Sectional Studies; Microsatellite Instability; Colorectal Neoplasms, Hereditary Nonpolyposis; Germ-Line Mutation; Endometrial Neoplasms; DNA Mismatch Repair; Colorectal Neoplasms
PubMed: 36251064
DOI: 10.1007/s00432-022-04397-0 -
Health Technology Assessment... Sep 2017Inherited mutations in deoxyribonucleic acid (DNA) mismatch repair (MMR) genes lead to an increased risk of colorectal cancer (CRC), gynaecological cancers and other... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Inherited mutations in deoxyribonucleic acid (DNA) mismatch repair (MMR) genes lead to an increased risk of colorectal cancer (CRC), gynaecological cancers and other cancers, known as Lynch syndrome (LS). Risk-reducing interventions can be offered to individuals with known LS-causing mutations. The mutations can be identified by comprehensive testing of the MMR genes, but this would be prohibitively expensive in the general population. Tumour-based tests - microsatellite instability (MSI) and MMR immunohistochemistry (IHC) - are used in CRC patients to identify individuals at high risk of LS for genetic testing. (MutL homologue 1) promoter methylation and V600E testing can be conducted on tumour material to rule out certain sporadic cancers.
OBJECTIVES
To investigate whether testing for LS in CRC patients using MSI or IHC (with or without promoter methylation testing and V600E testing) is clinically effective (in terms of identifying Lynch syndrome and improving outcomes for patients) and represents a cost-effective use of NHS resources.
REVIEW METHODS
Systematic reviews were conducted of the published literature on diagnostic test accuracy studies of MSI and/or IHC testing for LS, end-to-end studies of screening for LS in CRC patients and economic evaluations of screening for LS in CRC patients. A model-based economic evaluation was conducted to extrapolate long-term outcomes from the results of the diagnostic test accuracy review. The model was extended from a model previously developed by the authors.
RESULTS
Ten studies were identified that evaluated the diagnostic test accuracy of MSI and/or IHC testing for identifying LS in CRC patients. For MSI testing, sensitivity ranged from 66.7% to 100.0% and specificity ranged from 61.1% to 92.5%. For IHC, sensitivity ranged from 80.8% to 100.0% and specificity ranged from 80.5% to 91.9%. When tumours showing low levels of MSI were treated as a positive result, the sensitivity of MSI testing increased but specificity fell. No end-to-end studies of screening for LS in CRC patients were identified. Nine economic evaluations of screening for LS in CRC were identified. None of the included studies fully matched the decision problem and hence a new economic evaluation was required. The base-case results in the economic evaluation suggest that screening for LS in CRC patients using IHC, V600E and promoter methylation testing would be cost-effective at a threshold of £20,000 per quality-adjusted life-year (QALY). The incremental cost-effectiveness ratio for this strategy was £11,008 per QALY compared with no screening. Screening without tumour tests is not predicted to be cost-effective.
LIMITATIONS
Most of the diagnostic test accuracy studies identified were rated as having a risk of bias or were conducted in unrepresentative samples. There was no direct evidence that screening improves long-term outcomes. No probabilistic sensitivity analysis was conducted.
CONCLUSIONS
Systematic review evidence suggests that MSI- and IHC-based testing can be used to identify LS in CRC patients, although there was heterogeneity in the methods used in the studies identified and the results of the studies. There was no high-quality empirical evidence that screening improves long-term outcomes and so an evidence linkage approach using modelling was necessary. Key determinants of whether or not screening is cost-effective are the accuracy of tumour-based tests, CRC risk without surveillance, the number of relatives identified for cascade testing, colonoscopic surveillance effectiveness and the acceptance of genetic testing. Future work should investigate screening for more causes of hereditary CRC and screening for LS in endometrial cancer patients.
STUDY REGISTRATION
This study is registered as PROSPERO CRD42016033879.
FUNDING
The National Institute for Health Research Health Technology Assessment programme.
Topics: Colorectal Neoplasms, Hereditary Nonpolyposis; Cost-Benefit Analysis; DNA Mismatch Repair; Endometrial Neoplasms; England; Female; Genetic Testing; Humans; Microsatellite Instability; Quality-Adjusted Life Years
PubMed: 28895526
DOI: 10.3310/hta21510 -
Health Technology Assessment... Jun 2021Lynch syndrome is an inherited genetic condition that is associated with an increased risk of certain cancers. The National Institute for Health and Care Excellence has...
BACKGROUND
Lynch syndrome is an inherited genetic condition that is associated with an increased risk of certain cancers. The National Institute for Health and Care Excellence has recommended that people with colorectal cancer are tested for Lynch syndrome. Routine testing for Lynch syndrome among people with endometrial cancer is not currently conducted.
OBJECTIVES
To systematically review the evidence on the test accuracy of immunohistochemistry- and microsatellite instability-based strategies to detect Lynch syndrome among people who have endometrial cancer, and the clinical effectiveness and the cost-effectiveness of testing for Lynch syndrome among people who have been diagnosed with endometrial cancer.
DATA SOURCES
Searches were conducted in the following databases, from inception to August 2019 - MEDLINE ALL, EMBASE (both via Ovid), Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (both via Wiley Online Library), Database of Abstracts of Reviews of Effects, Health Technology Assessment Database (both via the Centre for Reviews and Dissemination), Science Citation Index, Conference Proceedings Citation Index - Science (both via Web of Science), PROSPERO international prospective register of systematic reviews (via the Centre for Reviews and Dissemination), NHS Economic Evaluation Database, Cost-Effectiveness Analysis Registry, EconPapers (Research Papers in Economics) and School of Health and Related Research Health Utilities Database. The references of included studies and relevant systematic reviews were also checked and experts on the team were consulted.
REVIEW METHODS
Eligible studies included people with endometrial cancer who were tested for Lynch syndrome using immunohistochemistry- and/or microsatellite instability-based testing [with or without mutL homologue 1 () promoter hypermethylation testing], with Lynch syndrome diagnosis being established though germline testing of normal (non-tumour) tissue for constitutional mutations in mismatch repair. The risk of bias in studies was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 tool, the Consolidated Health Economic Reporting Standards and the Philips' checklist. Two reviewers independently conducted each stage of the review. A meta-analysis of test accuracy was not possible because of the number and heterogeneity of studies. A narrative summary of test accuracy results was provided, reporting test accuracy estimates and presenting forest plots. The economic model constituted a decision tree followed by Markov models for the impact of colorectal and endometrial surveillance, and aspirin prophylaxis with a lifetime time horizon.
RESULTS
The clinical effectiveness search identified 3308 studies; 38 studies of test accuracy were included. (No studies of clinical effectiveness of endometrial cancer surveillance met the inclusion criteria.) Four test accuracy studies compared microsatellite instability with immunohistochemistry. No clear difference in accuracy between immunohistochemistry and microsatellite instability was observed. There was some evidence that specificity of immunohistochemistry could be improved with the addition of methylation testing. There was high concordance between immunohistochemistry and microsatellite instability. The economic model indicated that all testing strategies, compared with no testing, were cost-effective at a willingness-to-pay threshold of £20,000 per quality-adjusted life-year. Immunohistochemistry with promoter hypermethylation testing was the most cost-effective strategy, with an incremental cost-effectiveness ratio of £9420 per quality-adjusted life-year. The second most cost-effective strategy was immunohistochemistry testing alone, but incremental analysis produced an incremental cost-effectiveness ratio exceeding £130,000. Results were robust across all scenario analyses. Incremental cost-effectiveness ratios ranged from £5690 to £20,740; only removing the benefits of colorectal cancer surveillance produced an incremental cost-effectiveness ratio in excess of the £20,000 willingness-to-pay threshold. A sensitivity analysis identified the main cost drivers of the incremental cost-effectiveness ratio as percentage of relatives accepting counselling and prevalence of Lynch syndrome in the population. A probabilistic sensitivity analysis showed, at a willingness-to-pay threshold of £20,000 per quality-adjusted life-year, a 0.93 probability that immunohistochemistry with promoter hypermethylation testing is cost-effective, compared with no testing.
LIMITATIONS
The systematic review excluded grey literature, studies written in non-English languages and studies for which the reference standard could not be established. Studies were included when Lynch syndrome was diagnosed by genetic confirmation of constitutional variants in the four mismatch repair genes (i.e. , mutS homologue 2, mutS homologue 6 and postmeiotic segregation increased 2). Variants of uncertain significance were reported as per the studies. There were limitations in the economic model around uncertainty in the model parameters and a lack of modelling of the potential harms of gynaecological surveillance and specific pathway modelling of genetic testing for somatic mismatch repair mutations.
CONCLUSION
The economic model suggests that testing women with endometrial cancer for Lynch syndrome is cost-effective, but that results should be treated with caution because of uncertain model inputs.
FUTURE WORK
Randomised controlled trials could provide evidence on the effect of earlier intervention on outcomes and the balance of benefits and harms of gynaecological cancer surveillance. Follow-up of negative cases through disease registers could be used to determine false negative cases.
STUDY REGISTRATION
This study is registered as PROSPERO CRD42019147185.
FUNDING
This project was funded by the National Institute for Health Research (NIHR) Evidence Synthesis programme and will be published in full in ; Vol. 25, No. 42. See the NIHR Journals Library website for further project information.
Topics: Colorectal Neoplasms, Hereditary Nonpolyposis; Cost-Benefit Analysis; Endometrial Neoplasms; Female; Humans; Quality-Adjusted Life Years
PubMed: 34169821
DOI: 10.3310/hta25420