ABSTRACT
PURPOSE: Endometrial cancer (EC) is often the sentinel cancer in women with Lynch syndrome (LS). However, efforts to implement universal LS screening in EC patients have been hampered by a lack of evidence detailing the proportion of EC patients that would be expected to screen positive for LS. METHODS: Studies were identified by electronic searches of Medline, Embase, Cochrane CENTRAL and Web of Science. Proportions of test positivity were calculated by random and fixed-effects meta-analysis models. I2 score was used to assess heterogeneity across studies. RESULTS: Fifty-three studies, including 12,633 EC patients, met the inclusion criteria. The overall proportion of endometrial tumors with microsatellite instability or mismatch repair (MMR) deficiency by immunohistochemistry (IHC) was 0.27 (95% confidence interval [CI] 0.25-0.28, I2: 71%) and 0.26 (95% CI 0.25-0.27, I2: 88%), respectively. Of those women with abnormal tumor testing, 0.29 (95% CI 0.25-0.33, I2: 83%) had LS-associated pathogenic variants on germline testing; therefore around 3% of ECs can be attributed to LS. Preselection of EC cases did increase the proportion of germline LS diagnoses. CONCLUSION: The current study suggests that prevalence of LS in EC patients is approximately 3%, similar to that of colorectal cancer patients; therefore our data support the implementation of universal EC screening for LS.
Subject(s)
Colorectal Neoplasms, Hereditary Nonpolyposis/physiopathology , Endometrial Neoplasms/physiopathology , Adult , Brain Neoplasms/genetics , Colorectal Neoplasms/genetics , Colorectal Neoplasms, Hereditary Nonpolyposis/genetics , Comorbidity , DNA Mismatch Repair/genetics , Early Detection of Cancer , Endometrial Neoplasms/genetics , Female , Genetic Testing , Germ-Line Mutation , Humans , Immunohistochemistry , Microsatellite Instability , Middle Aged , Neoplastic Syndromes, Hereditary/geneticsABSTRACT
BACKGROUND: Minimising placebo response is essential for drug development. AIM: To conduct a meta-analysis to determine placebo response and remission rates in trials and identify the factors affecting these rates. METHODS: MEDLINE, EMBASE and CENTRAL were searched from inception to April 2014 for placebo-controlled trials of pharmacological interventions for Crohn's disease. Placebo response and remission rates for induction and maintenance trials were pooled by random-effects and mixed-effects meta-regression models to evaluate effects of study-level characteristics on these rates. RESULTS: In 100 studies containing 67 induction and 40 maintenance phases and 7638 participants, pooled placebo remission and response rates for induction trials were 18% [95% confidence interval (CI) 16-21%] and 28% (95% CI 24-32%), respectively. Corresponding values for maintenance trials were 32% (95% CI 25-39%) and 26% (95% CI 19-35%), respectively. For remission, trials enrolling patients with more severe disease activity, longer disease duration and more study centres were associated with lower placebo rates, whereas more study visits and longer study duration was associated with higher placebo rates. For response, findings were opposite such that trials enrolling patients with less severe disease activity and longer study duration were associated with lower placebo rates. Placebo rates varied by drug class and route of administration, with the highest placebo response rates observed for biologics. CONCLUSIONS: Placebo rates vary according to whether trials are designed for induction or maintenance and the factors influencing them differ for the endpoints of remission and response. These findings have important implications for clinical trial design in Crohn's disease.
