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The National Medical Journal of India 2017Clinical trials have shown that early and deeper cytogenetic/ molecular responses to tyrosine kinase inhibitors (TKIs) help in achieving improved long-term outcomes... (Review)
Review
Clinical trials have shown that early and deeper cytogenetic/ molecular responses to tyrosine kinase inhibitors (TKIs) help in achieving improved long-term outcomes including lower rates of disease progression in chronic myeloid leukaemia (CML). However, the level of molecular responses achieved with TKI therapy in patients with CML is variable and this could be explained by differences in adherence to CML therapy. A systematic literature review of CML studies reporting adherence to BCR-ABL inhibitors from the USA, Asia and Europe (19 articles: 9 retrospective, 4 prospective, rest cross-sectional) showed that average adherence varies from 19% to 100% of the proportion of prescribed drug taken. Some factors that contribute to non-adherence include patient attitudes, adverse events associated with therapy, treatment complexities and socioeconomic issues. This article focuses on the problem of non-adherence to therapy in CML, especially from an Indian perspective, and offers suggestions for its mitigation.
Topics: Cross-Sectional Studies; Fusion Proteins, bcr-abl; Humans; India; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Prospective Studies; Protein Kinase Inhibitors; Retrospective Studies
PubMed: 28936999
DOI: No ID Found -
The Cochrane Database of Systematic... Jun 2017Epidermal growth factor receptor (EGFR) inhibitors prevent cell growth and have shown benefit in the treatment of metastatic colorectal cancer, whether used as single... (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Epidermal growth factor receptor (EGFR) inhibitors prevent cell growth and have shown benefit in the treatment of metastatic colorectal cancer, whether used as single agents or in combination with chemotherapy. Clear benefit has been shown in trials of EGFR monoclonal antibodies (EGFR MAb) but not EGFR tyrosine kinase inhibitors (EGFR TKI). However, there is ongoing debate as to which patient populations gain maximum benefit from EGFR inhibition and where they should be used in the metastatic colorectal cancer treatment paradigm to maximise efficacy and minimise toxicity.
OBJECTIVES
To determine the efficacy, safety profile, and potential harms of EGFR inhibitors in the treatment of people with metastatic colorectal cancer when given alone, in combination with chemotherapy, or with other biological agents.The primary outcome of interest was progression-free survival; secondary outcomes included overall survival, tumour response rate, quality of life, and adverse events.
SEARCH METHODS
We searched the Cochrane Central Register of Controlled Trials (CENTRAL), the Cochrane Library, Issue 9, 2016; Ovid MEDLINE (from 1950); and Ovid Embase (from 1974) on 9 September 2016; and ClinicalTrials.gov and the World Health Organization International Clinical Trials Registry Platform (WHO ICTRP) on 14 March 2017. We also searched proceedings from the major oncology conferences ESMO, ASCO, and ASCO GI from 2012 to December 2016. We further scanned reference lists from eligible publications and contacted corresponding authors for trials for further information where needed.
SELECTION CRITERIA
We included randomised controlled trials on participants with metastatic colorectal cancer comparing: 1) the combination of EGFR MAb and 'standard therapy' (whether chemotherapy or best supportive care) to standard therapy alone, 2) the combination of EGFR TKI and standard therapy to standard therapy alone, 3) the combination of EGFR inhibitor (whether MAb or TKI) and standard therapy to another EGFR inhibitor (or the same inhibitor with a different dosing regimen) and standard therapy, or 4) the combination of EGFR inhibitor (whether MAb or TKI), anti-angiogenic therapy, and standard therapy to anti-angiogenic therapy and standard therapy alone.
DATA COLLECTION AND ANALYSIS
We used standard methodological procedures defined by Cochrane. Summary statistics for the endpoints used hazard ratios (HR) with 95% confidence intervals (CI) for overall survival and progression-free survival, and odds ratios (OR) for response rate (RR) and toxicity. Subgroup analyses were performed by Kirsten rat sarcoma viral oncogene homolog (KRAS) and neuroblastoma RAS viral (V-Ras) oncogene homolog (NRAS) status - firstly by status of KRAS exon 2 testing (mutant or wild type) and also by status of extended KRAS/NRAS testing (any mutation present or wild type).
MAIN RESULTS
We identified 33 randomised controlled trials for analysis (15,025 participants), including trials of both EGFR MAb and EGFR TKI. Looking across studies, significant risk of bias was present, particularly with regard to the risk of selection bias (15/33 unclear risk, 1/33 high risk), performance bias (9/33 unclear risk, 9/33 high risk), and detection bias (7/33 unclear risk, 11/33 high risk).The addition of EGFR MAb to standard therapy in the KRAS exon 2 wild-type population improves progression-free survival (HR 0.70, 95% CI 0.60 to 0.82; high-quality evidence), overall survival (HR 0.88, 95% CI 0.80 to 0.98; high-quality evidence), and response rate (OR 2.41, 95% CI 1.70 to 3.41; high-quality evidence). We noted evidence of significant statistical heterogeneity in all three of these analyses (progression-free survival: I = 76%; overall survival: I = 40%; and response rate: I = 77%), likely due to pooling of studies investigating EGFR MAb use in different lines of therapy. Rates of overall grade 3 to 4 toxicity, diarrhoea, and rash were increased (moderate-quality evidence for all three outcomes), but there was no evidence for increased rates of neutropenia.For the extended RAS wild-type population (no mutations in KRAS or NRAS), addition of EGFR MAb improved progression-free survival (HR 0.60, 95% CI 0.48 to 0.75; moderate-quality evidence) and overall survival (HR 0.77, 95% CI 0.67 to 0.88; high-quality evidence). Response rate was also improved (OR 4.28, 95% CI 2.61 to 7.03; moderate-quality evidence). We noted significant statistical heterogeneity in the progression-free survival analysis (I = 61%), likely due to the pooling of studies combining EGFR MAb with chemotherapy with monotherapy studies.We observed no evidence of a statistically significant difference when EGFR MAb was compared to bevacizumab, in progression-free survival (HR 1.02, 95% CI 0.93 to 1.12; high quality evidence) or overall survival (HR 0.84, 95% CI 0.70 to 1.01; moderate-quality evidence). We noted significant statistical heterogeneity in the overall survival analysis (I = 51%), likely due to the pooling of first-line and second-line studies.The addition of EGFR TKI to standard therapy in molecularly unselected participants did not show benefit in limited data sets (meta-analysis not performed). The addition of EGFR MAb to bevacizumab plus chemotherapy in people with KRAS exon 2 wild-type metastatic colorectal cancer did not improve progression-free survival (HR 1.04, 95% CI 0.83 to 1.29; very low quality evidence), overall survival (HR 1.00, 95% CI 0.69 to 1.47; low-quality evidence), or response rate (OR 1.20, 95% CI 0.67 to 2.12; very low-quality evidence) but increased toxicity (OR 2.57, 95% CI 1.45 to 4.57; low-quality evidence). We noted significant between-study heterogeneity in most analyses.Scant information on quality of life was reported in the identified studies.
AUTHORS' CONCLUSIONS
The addition of EGFR MAb to either chemotherapy or best supportive care improves progression-free survival (moderate- to high-quality evidence), overall survival (high-quality evidence), and tumour response rate (moderate- to high-quality evidence), but may increase toxicity in people with KRAS exon 2 wild-type or extended RAS wild-type metastatic colorectal cancer (moderate-quality evidence). The addition of EGFR TKI to standard therapy does not improve clinical outcomes. EGFR MAb combined with bevacizumab is of no clinical value (very low-quality evidence). Future studies should focus on optimal sequencing and predictive biomarkers and collect quality of life data.
Topics: Antibodies, Monoclonal; Antineoplastic Agents; Bevacizumab; Colorectal Neoplasms; Diarrhea; Disease-Free Survival; ErbB Receptors; Exanthema; Humans; Neutropenia; Protein Kinase Inhibitors; Protein-Tyrosine Kinases; Proto-Oncogene Proteins p21(ras); Quality of Life; Randomized Controlled Trials as Topic
PubMed: 28654140
DOI: 10.1002/14651858.CD007047.pub2 -
Medicine Aug 2015The strong association between bcl-2-like 11 (BIM) triggered apoptosis and the presence of epidermal growth factor receptor (EGFR) mutations has been proven in nonsmall... (Meta-Analysis)
Meta-Analysis
The strong association between bcl-2-like 11 (BIM) triggered apoptosis and the presence of epidermal growth factor receptor (EGFR) mutations has been proven in nonsmall cell lung cancer (NSCLC). However, the relationship between EGFR-tyrosine kinase inhibitor's (TKI's) efficacy and BIM polymorphism in NSCLC EGFR is still unclear.Electronic databases were searched for eligible literatures. Data on objective response rates (ORRs), disease control rates (DCRs), and progression-free survival (PFS) stratified by BIM polymorphism status were extracted and synthesized based on random-effect model. Subgroup and sensitivity analyses were conducted.A total of 6 studies that involved a total of 773 EGFR mutant advanced NSCLC patients after EGFR-TKI treatment were included. In overall, non-BIM polymorphism patients were associated with significant prolonged PFS (hazard ratio 0.63, 0.47-0.83, P = 0.001) compared to patients with BIM polymorphism. However, only marginal improvements without statistical significance in ORR (odds ratio [OR] 1.71, 0.91-3.24, P = 0.097) and DCR (OR 1.56, 0.85-2.89, P = 0.153) were observed. Subgroup analyses showed that the benefits of PFS in non-BIM polymorphism group were predominantly presented in pooled results of studies involving chemotherapy-naive and the others, and retrospective studies. Additionally, we failed to observe any significant benefit from patients without BIM polymorphism in every subgroup for ORR and DCR.For advanced NSCLC EGFR mutant patients, non-BIM polymorphism ones are associated with longer PFS than those with BIM polymorphism after EGFR-TKIs treatment. BIM polymorphism status should be considered an essential factor in studies regarding EGFR-targeted agents toward EGFR mutant patients.
Topics: Apoptosis; Apoptosis Regulatory Proteins; Bcl-2-Like Protein 11; Carcinoma, Non-Small-Cell Lung; Drug Resistance, Neoplasm; ErbB Receptors; Genes, erbB-1; Humans; Membrane Proteins; Mutation; Polymorphism, Genetic; Protein Kinase Inhibitors; Proto-Oncogene Proteins; Treatment Outcome
PubMed: 26287412
DOI: 10.1097/MD.0000000000001263 -
Scientific Reports Feb 2015Current data on the concordance of KRAS, BRAF, PIK3CA mutation status or PTEN expression status between primary tumors and metastases in colorectal cancer (CRC) are... (Meta-Analysis)
Meta-Analysis Review
Current data on the concordance of KRAS, BRAF, PIK3CA mutation status or PTEN expression status between primary tumors and metastases in colorectal cancer (CRC) are conflicting. We conducted a systematic review and meta-analysis to examine concordance and discordance of the status of these four biomarkers between primary tumors and corresponding metastases in CRC patients. The biomarker status in primary tumors was used as the reference standard. Concordance data for KRAS, BRAF, PIK3CA and PTEN were provided by 43, 16, 9 and 7 studies, respectively. The pooled concordance rate was 92.0% (95% CI: 89.7%-93.9%) for KRAS, 96.8% (95% CI: 94.8%-98.0%) for BRAF, 93.9% (95% CI: 89.7%-96.5%) for PIK3CA and 71.7% (95% CI: 57.6%-82.5%) for PTEN. The pooled false positive and false negative rates for KRAS were 9.0% (95% CI: 6.5%-12.4%) and 11.3% (95% CI: 8.0%-15.8%), respectively. KRAS, BRAF and PIK3CA mutations are highly concordant between primary tumors and corresponding metastases in CRC, but PTEN loss is not. Nine percent of patients with wild-type KRAS in primary tumors who received anti-EGFR treatment had mutant KRAS in metastases, while 11.3% patients with mutant KRAS primary tumors had wild-type KRAS in the metastases. These 11.3% patients currently do not receive potentially beneficial anti-EGFR treatment.
Topics: Biomarkers, Tumor; Class I Phosphatidylinositol 3-Kinases; Colorectal Neoplasms; Databases, Factual; Humans; Liver Neoplasms; Lymph Nodes; Lymphatic Metastasis; Mutation; PTEN Phosphohydrolase; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins B-raf; ras Proteins
PubMed: 25639985
DOI: 10.1038/srep08065 -
PloS One 2014The survival rate of colorectal cancer (CRC) patients carrying wild-type KRAS is significantly increased by combining anti-EGFR monoclonal antibody (mAb) with standard... (Meta-Analysis)
Meta-Analysis Review
PCR-based assays versus direct sequencing for evaluating the effect of KRAS status on anti-EGFR treatment response in colorectal cancer patients: a systematic review and meta-analysis.
BACKGROUND
The survival rate of colorectal cancer (CRC) patients carrying wild-type KRAS is significantly increased by combining anti-EGFR monoclonal antibody (mAb) with standard chemotherapy. However, conflicting data exist in both the wild-type KRAS and mutant KRAS groups, which strongly challenge CRC anti-EGFR treatment. Here we conducted a meta-analysis in an effort to provide more reliable information regarding anti-EGFR treatment in CRC patients.
METHODS
We searched full reports of randomized clinical trials using Medline, the American Society of Clinical Oncology (ASCO), and the European Society for Medical Oncology (ESMO). Two investigators independently screened the published literature according to our inclusive and exclusive criteria and the relative data were extracted. We used Review Manager 5.2 software to analyze the data.
RESULTS
The addition of anti-EGFR mAb to standard chemotherapy significantly improved both progression-free survival (PFS) and median overall survival (mOS) in the wild-type KRAS group; hazard ratios (HRs) for PFS and mOS were 0.70 [95% confidence interval (CI), 0.58-0.84] and 0.83 [95% CI, 0.75-0.91], respectively. In sub-analyses of the wild-type KRAS group, when PCR-based assays are employed, PFS and mOS notably increase: the HRs were 0.74 [95% CI, 0.62-0.88] and 0.87 [95% CI, 0.78-0.96], respectively. In sub-analyses of the mutant KRAS group, neither PCR-based assays nor direct sequencing enhance PFS or mOS.
CONCLUSION
Our data suggest that PCR-based assays with high sensitivity and specificity allow accurate identification of patients with wild-type KRAS and thus increase PFS and mOS. Furthermore, such assays liberate patients with mutant KRAS from unnecessary drug side effects, and provide them an opportunity to receive appropriate treatment. Thus, establishing a precise standard reference test will substantially optimize CRC-targeted therapies.
Topics: Antibodies, Monoclonal; Antineoplastic Combined Chemotherapy Protocols; Colorectal Neoplasms; ErbB Receptors; Humans; Mutation; Proto-Oncogene Proteins; Proto-Oncogene Proteins p21(ras); Randomized Controlled Trials as Topic; ras Proteins
PubMed: 25260023
DOI: 10.1371/journal.pone.0107926 -
Haematologica Mar 2014BCR-ABL inhibitors for treating chronic myeloid leukemia in chronic phase have transformed a previously incurable malignancy into a manageable condition. However,... (Meta-Analysis)
Meta-Analysis Review
BCR-ABL inhibitors for treating chronic myeloid leukemia in chronic phase have transformed a previously incurable malignancy into a manageable condition. However, suboptimal medication adherence has been observed with these agents affecting clinical outcomes and healthcare costs. In order to raise awareness of the problem of adherence, and before developing pragmatic strategies to enhance medication adherence, a deep understanding of the best approaches for measuring adherence in chronic myeloid leukemia patients and identifying non-adherence is required. A systematic literature review on the prevalence, measurement methods, consequences and risk factors for non-adherence to BCR-ABL inhibitors and adherence-enhancing interventions was performed and critically appraised. Of the 19 included articles, 9 were retrospective. Average adherence varied from 19% to almost 100% of the proportion of prescribed drug taken, but it was measured through various different methods and within different study groups. Suboptimal adherence was associated with a negative impact on both clinical and economic outcomes. There is a lack of supportive evidence demonstrating a difference in adherence across BCR-ABL inhibitors and even contradictory results between the 2(nd) generation inhibitors. Drug-related adverse events and forgetfulness were common reasons for intentional and unintentional non-adherence, respectively, but further research is required to identify additional reasons behind non-adherence or patients at risk of non-adherence. Non-adherence in chronic myeloid leukemia patients treated with BCR-ABL inhibitors is common and associated with critical outcomes. However, this review highlights important existing gaps, reveals inconsistent definitions, and a lack of standardized methods for measuring adherence in chronic myeloid leukemia. All require further investigation.
Topics: Antineoplastic Agents; Fusion Proteins, bcr-abl; Humans; Leukemia, Myelogenous, Chronic, BCR-ABL Positive; Medication Adherence; Patient Compliance; Protein Kinase Inhibitors
PubMed: 24598855
DOI: 10.3324/haematol.2012.082511 -
PloS One 2013K-ras gene mutations were common in colorectal patients, but their relationship with prognosis was unclear. (Meta-Analysis)
Meta-Analysis Review
INTRODUCTION
K-ras gene mutations were common in colorectal patients, but their relationship with prognosis was unclear.
OBJECTIVE
Verify prognostic differences between patient with and without mutant K-ras genes by reviewing the published evidence.
METHOD
Systematic reviews and data bases were searched for cohort/case-control studies of prognosis of colorectal cancer patients with detected K-ras mutations versus those without mutant K-ras genes, both of whom received chemotherapy. Number of patients, regimens of chemotherapy, and short-term or long-term survival rate (disease-free or overall) were extracted. Quality of studies was also evaluated.
PRINCIPAL FINDINGS
7 studies of comparisons with a control group were identified. No association between K-ras gene status with neither short-term disease free-survival (OR=1.01, 95% CI, 0.73-1.38, P=0.97) nor overall survival (OR=1.06, 95% CI, 0.82-1.36, P=0.66) in CRC patients who received chemotherapy was indicated. Comparison of long-term survival between two groups also indicated no significant difference after heterogeneity was eliminated (OR=1.09, 95% CI, 0.85-1.40, P=0.49).
CONCLUSIONS
K-ras gene mutations may not be a prognostic index for colorectal cancer patients who received chemotherapy.
Topics: Antineoplastic Combined Chemotherapy Protocols; Biomarkers, Tumor; Case-Control Studies; Colorectal Neoplasms; Humans; Mutation; Prognosis; Proto-Oncogene Proteins; Proto-Oncogene Proteins p21(ras); Survival Rate; ras Proteins
PubMed: 24205021
DOI: 10.1371/journal.pone.0077901 -
Malaria Journal Aug 2010Mutations in the dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) genes of Plasmodium falciparum are associated with resistance to anti-folate drugs,... (Review)
Review
Anti-folate drug resistance in Africa: meta-analysis of reported dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) mutant genotype frequencies in African Plasmodium falciparum parasite populations.
BACKGROUND
Mutations in the dihydrofolate reductase (dhfr) and dihydropteroate synthase (dhps) genes of Plasmodium falciparum are associated with resistance to anti-folate drugs, most notably sulphadoxine-pyrimethamine (SP). Molecular studies document the prevalence of these mutations in parasite populations across the African continent. However, there is no systematic review examining the collective epidemiological significance of these studies. This meta-analysis attempts to: 1) summarize genotype frequency data that are critical for molecular surveillance of anti-folate resistance and 2) identify the specific challenges facing the development of future molecular databases.
METHODS
This review consists of 220 studies published prior to 2009 that report the frequency of select dhfr and dhps mutations in 31 African countries. Maps were created to summarize the location and prevalence of the highly resistant dhfr triple mutant (N51I, C59R, S108N) genotype and dhps double mutant (A437G and K540E) genotype in Africa. A hierarchical mixed effects logistic regression was used to examine the influence of various factors on reported mutant genotype frequency. These factors include: year and location of study, age and clinical status of sampled population, and reporting conventions for mixed genotype data.
RESULTS
A database consisting of dhfr and dhps mutant genotype frequencies from all African studies that met selection criteria was created for this analysis. The map illustrates particularly high prevalence of both the dhfr triple and dhps double mutant genotypes along the Kenya-Tanzania border and Malawi. The regression model shows a statistically significant increase in the prevalence of both the dhfr triple and dhps double mutant genotypes in Africa.
CONCLUSION
Increasing prevalence of the dhfr triple mutant and dhps double mutant genotypes in Africa are consistent with the loss of efficacy of SP for treatment of clinical malaria in most parts of this continent. Continued assessment of the effectiveness of SP for the treatment of clinical malaria and intermittent preventive treatment in pregnancy is needed. The creation of a centralized resistance data network, such as the one proposed by the WorldWide Antimalarial Resistance Network (WWARN), will become a valuable resource for planning timely actions to combat drug resistant malaria.
Topics: Africa; Amino Acid Substitution; Antimalarials; DNA, Protozoan; Dihydropteroate Synthase; Drug Combinations; Drug Resistance; Gene Frequency; Genotype; Humans; Mutant Proteins; Mutation, Missense; Plasmodium falciparum; Protozoan Proteins; Pyrimethamine; Sulfadoxine; Tetrahydrofolate Dehydrogenase
PubMed: 20799995
DOI: 10.1186/1475-2875-9-247 -
Clinical Orthopaedics and Related... Sep 2008Establishing the best diagnosis for musculoskeletal neoplasms requires a multidisciplinary approach using clinical, radiographic, and histologic analyses. Despite this... (Review)
Review
UNLABELLED
Establishing the best diagnosis for musculoskeletal neoplasms requires a multidisciplinary approach using clinical, radiographic, and histologic analyses. Despite this rigorous approach, establishing accurate diagnoses and prognoses remains challenging. Improved diagnostic methods are expected as unique molecular signals for specific bone and soft tissue cancers are identified. We performed a systematic review of the best available evidence to explore three major applications of molecular genetics that will best benefit clinical management of musculoskeletal neoplasms: diagnostic, prognostic, and therapeutic applications. The specific questions addressed in this systematic review are: (1) What sets of histopathologic sarcoma subtypes will benefit from molecular evaluation and diagnosis? (2) What molecular methods are best applied to histopathologic sarcomas to distinguish between major subtypes? (3) How do the molecular patterns discovered on genetic diagnosis affect prognosis of certain sarcomas? (4) Which sarcoma translocations can benefit from an improved response and outcome using existing and forthcoming pharmacogenetic approaches targeting molecular events? This review summarizes recent advances in molecular genetics that are available and will soon be available to clinicians to better predict outcomes and subsequently help make future treatment decisions.
LEVEL OF EVIDENCE
Level IV, diagnostic study. See the Guidelines for Authors for a complete description of levels of evidence.
Topics: Algorithms; Bone Neoplasms; Humans; Immunochemistry; Karyotyping; Muscle Neoplasms; Oncogene Proteins, Fusion; Prognosis; RNA-Binding Protein EWS; RNA-Binding Protein FUS; Reverse Transcriptase Polymerase Chain Reaction; Sarcoma; Signal Transduction; Transcription Factor CHOP; Translocation, Genetic
PubMed: 18566876
DOI: 10.1007/s11999-008-0342-0