ABSTRACT
It is unclear whether young adults with chronic obstructive pulmonary disease (COPD) are at an increased risk of rapid lung function decline. A total of 2,934 Korean adults aged 40–49 years who had consecutive lung function measurements were included. COPD was defined as pre-bronchodilator forced expiratory volume in 1 second (FEV 1 )/forced vital capacity < lower limit of normal. The risk of rapid decline in FEV 1 , defined as ≥ 60 mL/year, was assessed using multivariable logistic regression analysis. In the multivariable model, a significantly higher risk of rapid decline in FEV 1 was observed for the COPD group compared with the non-COPD group (adjusted odds ratio, 1.89; 95% confidence interval, 1.18–2.95), which was especially significant in subjects with FEV 1 less than the median value (< 110%pred) (P interaction = 0.017) and inactive physical activity (P interaction = 0.039). In conclusion, the risk of rapid FEV 1 decline was higher in young adults with COPD than in those without COPD, especially in those with FEV 1 less than the median value and inactive physical activity.
ABSTRACT
Background/Aims@#The overall incidence of pneumococcal pneumonia is declining. However, the change in the pathogenic distribution of community-acquired pneumonia (CAP) in chronic obstructive pulmonary disease (COPD) patients and the serotype specificity of Streptococcus pneumoniae have not been evaluated in the post-era of pneumococcal vaccination in Korea. @*Methods@#We conducted a prospective, multi-center, cohort study from seven University-affiliated hospitals. The primary objective was the identification of serotype-specific prevalence of pneumococcal pneumonia in COPD patients hospitalized for CAP. For the purpose, we conducted serotype-specific urine antigen detection (SS-UAD) assays for S. pneumoniae. The secondary objectives were other clinical characteristics of pneumonia including vaccination status. @*Results@#The total number of participants was 349. Most of them were male (95.1%) with old ages (75.55 ± 8.59 y). The positive rate for S. pneumoniae was 9.2% with SS-UAD assay and the common serotypes were 22F, 6A, and 6B. In the sputum, Pseudomonas aeruginosa (5.0%) and Haemophilus influenzae (4.0%) were common pathogens. The vaccination rate was 78.8%, 53.0%, and 25.8% for influenza, pneumococcal polysaccharide vaccine 23 (PPV 23), and pneumococcal protein- conjugated vaccine 13 (PCV 13), respectively. Thirteen patients died during hospitalization (mortality rate; 3.7%). There was no difference in the respective rate of influenza vaccination (79.2% vs. 69.2%, p = 0.288) and PCV 13 vaccination (25.6% vs. 30.8%, p = 0.443) between survivors and the deceased. @*Conclusions@#Serotypes 22F, 6A, and 6B, which are covered either by PPV 23 or by PCV 13, are still common pneumococcal serotypes in COPD pneumonia in the post-vaccination era in Korea.
ABSTRACT
Background@#Because the etiologies of bronchiectasis and related diseases vary significantly among different regions and ethnicities, this study aimed to develop a diagnostic bundle for bronchiectasis in South Korea. @*Methods@#A modified Delphi method was used to develop expert consensus statements on a diagnostic bundle for bronchiectasis in South Korea. Initial statements proposed by a core panel, based on international bronchiectasis guidelines, were discussed in an online meeting and two email surveys by a panel of experts (≥70% agreement). @*Results@#The study involved 21 expert participants, and 30 statements regarding a diagnostic bundle for bronchiectasis were classified as recommended, conditional, or not recommended. The consensus statements of the expert panel were as follows: A standardized diagnostic bundle is useful in clinical practice; diagnostic tests for specific diseases, including immunodeficiency and allergic bronchopulmonary aspergillosis, are necessary when clinically suspected; initial diagnostic tests, including sputum microbiology and spirometry, are essential in all patients with bronchiectasis, and patients suspected with rare causes such as primary ciliary dyskinesia should be referred to specialized centers. @*Conclusion@#Based on this Delphi survey, expert consensus statements were generated including specific diagnostic, laboratory, microbiological, and pulmonary function tests required to manage patients with bronchiectasis in South Korea.
ABSTRACT
Patients with non-cystic fibrosis bronchiectasis (hereafter referred to as bronchiectasis) often present with comorbidities. These comorbidities significantly impact symptoms, acute exacerbation, hospitalization, disease progression, and mortality in patients with bronchiectasis. Thus, accurate diagnosis and management of comorbidities associated with bronchiectasis are essential to reduce the disease burden of bronchiectasis. This review provides a state-of-the-art summary of key pulmonary and extra-pulmonary comorbidities associated with bronchiectasis, outlines clinical tools to quantify the prognosis of bronchiectasis, and suggests a workflow to diagnose and manage comorbidities associated with bronchiectasis.
ABSTRACT
Background/Aims@#Although international guidelines for bronchiectasis management have been published in Western countries, there is a lack of data about their application in Asian populations including patients with different phenotypes. We aimed to investigate the current status of bronchiectasis management in Asian populations. @*Methods@#A nationwide questionnaire survey was performed of Asian respiratory specialists from South Korea, Japan, Taiwan, Singapore, Vietnam, and Sri Lanka. Participants were invited by e-mail to answer a questionnaire comprising 25 questions based on international guidelines for the management of bronchiectasis. @*Results@#A total of 221 physicians participated in the survey. About half of them were Korean (50.2%), with the next most common nationalities being Japanese (23.1%), Taiwanese (13.6%), and Singaporean (7.7%). Only 18 (8.1%) responders had local guidelines for bronchiectasis. While 85 (38.5%) responders checked sputum acid-fast bacillus smear/culture about 1 to 3 times per year, only a small proportion of responders routinely performed a serum immunoglobulin test (36/221, 16.3%) or evaluated for allergic bronchopulmonary aspergillosis (41/221, 18.6%). Less than half (43.4%) of responders performed eradication treatment in patients with drug-sensitive Pseudomonas aeruginosa infection, mainly due to the limited availability of inhaled antibiotics (34.8%). In addition, 58.6% of responders considered physiotherapy such as airway clearance and pulmonary rehabilitation. @*Conclusions@#Discrepancies might exist between guideline recommendations and practice for bronchiectasis management in Asian populations, partly due to the limited availability of treatment in each country. The development of local guidelines that consider the phenotypes and situation will help to standardize and improve the management of bronchiectasis.
ABSTRACT
Cough is the most common respiratory symptom that can have various causes. It is a major clinical problem that can reduce a patient’s quality of life. Thus, clinical guidelines for the treatment of cough were established in 2014 by the cough guideline committee under the Korean Academy of Tuberculosis and Respiratory Diseases. From October 2018 to July 2020, cough guidelines were revised by members of the committee based on the first guidelines. The purpose of these guidelines is to help clinicians efficiently diagnose and treat patients with cough. This article highlights the recommendations and summary of the revised Korean cough guidelines. It includes a revised algorithm for the evaluation of acute, subacute, and chronic cough. For a chronic cough, upper airway cough syndrome (UACS), cough variant asthma (CVA), and gastroesophageal reflux disease (GERD) should be considered in differential diagnoses. If UACS is suspected, first-generation antihistamines and nasal decongestants can be used empirically. In cases with CVA, inhaled corticosteroids are recommended to improve cough. In patients with suspected chronic cough due to symptomatic GERD, proton pump inhibitors are recommended. Chronic bronchitis, bronchiectasis, bronchiolitis, lung cancer, aspiration, intake of angiotensin-converting enzyme inhibitor, intake of dipeptidyl peptidase-4 inhibitor, habitual cough, psychogenic cough, interstitial lung disease, environmental and occupational factors, tuberculosis, obstructive sleep apnea, peritoneal dialysis, and unexplained cough can also be considered as causes of a chronic cough. Chronic cough due to laryngeal dysfunction syndrome has been newly added to the guidelines.
ABSTRACT
Purpose@#This study aimed to analyze whether patients with lung cancer have a higher susceptibility of coronavirus disease 2019 (COVID-19), severe presentation, and higher mortality than those without lung cancer. @*Materials and Methods@#A nationwide cohort of confirmed COVID-19 (n=8,070) between January 1, 2020, and May 30, 2020, and a 1:15 age-, sex-, and residence-matched cohort (n=121,050) were constructed. A nested case-control study was performed to compare the proportion of patients with lung cancer between the COVID-19 cohort and the matched cohort. @*Results@#The proportion of patients with lung cancer was significantly higher in the COVID-19 cohort (0.5% [37/8,070]) than in the matched cohort (0.3% [325/121,050]) (p=0.002). The adjusted odds ratio [OR] of having lung cancer was significantly higher in the COVID-19 cohort than in the matched cohort (adjusted OR, 1.51; 95% confidence interval [CI], 1.05 to 2.10). Among patients in the COVID-19 cohort, compared to patients without lung cancer, those with lung cancer were more likely to have severe COVID-19 (54.1% vs. 13.2%, p < 0.001), including mortality (18.9% vs. 2.8%, p < 0.001). The adjusted OR for the occurrence of severe COVID-19 in patients with lung cancer relative to those without lung cancer was 2.24 (95% CI, 1.08 to 4.74). @*Conclusion@#The risk of COVID-19 occurrence and severe presentation, including mortality, may be higher in patients with lung cancer than in those without lung cancer.
ABSTRACT
Cough is the most common respiratory symptom that can have various causes. It is a major clinical problem that can reduce a patient’s quality of life. Thus, clinical guidelines for the treatment of cough were established in 2014 by the cough guideline committee under the Korean Academy of Tuberculosis and Respiratory Diseases. From October 2018 to July 2020, cough guidelines were revised by members of the committee based on the first guidelines. The purpose of these guidelines is to help clinicians efficiently diagnose and treat patients with cough. This article highlights the recommendations and summary of the revised Korean cough guidelines. It includes a revised algorithm for the evaluation of acute, subacute, and chronic cough. For a chronic cough, upper airway cough syndrome (UACS), cough variant asthma (CVA), and gastroesophageal reflux disease (GERD) should be considered in differential diagnoses. If UACS is suspected, first-generation antihistamines and nasal decongestants can be used empirically. In cases with CVA, inhaled corticosteroids are recommended to improve cough. In patients with suspected chronic cough due to symptomatic GERD, proton pump inhibitors are recommended. Chronic bronchitis, bronchiectasis, bronchiolitis, lung cancer, aspiration, intake of angiotensin-converting enzyme inhibitor, intake of dipeptidyl peptidase-4 inhibitor, habitual cough, psychogenic cough, interstitial lung disease, environmental and occupational factors, tuberculosis, obstructive sleep apnea, peritoneal dialysis, and unexplained cough can also be considered as causes of a chronic cough. Chronic cough due to laryngeal dysfunction syndrome has been newly added to the guidelines.
ABSTRACT
Purpose@#This study aimed to analyze whether patients with lung cancer have a higher susceptibility of coronavirus disease 2019 (COVID-19), severe presentation, and higher mortality than those without lung cancer. @*Materials and Methods@#A nationwide cohort of confirmed COVID-19 (n=8,070) between January 1, 2020, and May 30, 2020, and a 1:15 age-, sex-, and residence-matched cohort (n=121,050) were constructed. A nested case-control study was performed to compare the proportion of patients with lung cancer between the COVID-19 cohort and the matched cohort. @*Results@#The proportion of patients with lung cancer was significantly higher in the COVID-19 cohort (0.5% [37/8,070]) than in the matched cohort (0.3% [325/121,050]) (p=0.002). The adjusted odds ratio [OR] of having lung cancer was significantly higher in the COVID-19 cohort than in the matched cohort (adjusted OR, 1.51; 95% confidence interval [CI], 1.05 to 2.10). Among patients in the COVID-19 cohort, compared to patients without lung cancer, those with lung cancer were more likely to have severe COVID-19 (54.1% vs. 13.2%, p < 0.001), including mortality (18.9% vs. 2.8%, p < 0.001). The adjusted OR for the occurrence of severe COVID-19 in patients with lung cancer relative to those without lung cancer was 2.24 (95% CI, 1.08 to 4.74). @*Conclusion@#The risk of COVID-19 occurrence and severe presentation, including mortality, may be higher in patients with lung cancer than in those without lung cancer.
ABSTRACT
Background@#Hepatocellular carcinoma (HCC) is the second-most-common cause of cancer-related deaths worldwide, and an accurate and non-invasive biomarker for the early detection and monitoring of HCC is required. We assessed pathogenic variants of HCC driver genes in cell-free DNA (cfDNA) from HCC patients who had not undergone systemic therapy. @*Methods@#Plasma cfDNA was collected from 20 HCC patients, and deep sequencing was performed using a customized cfDNA next-generation sequencing panel, targeting the major HCC driver genes (TP53, CTNNB1, TERT) that incorporates molecular barcoding. @*Results@#In 13/20 (65%) patients, we identified at least one pathogenic variant of two major HCC driver genes (TP53 and CTNNB1), including 16 variants of TP53 and nine variants of CTNNB1. The TP53 and CTNNB1 variants showed low allele frequencies, with median values of 0.17% (range: 0.06%–6.99%) and 0.07% (range: 0.05%–0.96%), respectively. However, the molecular coverage of variants was sufficient, with median values of 5,543 (range: 2,317–9,088) and 7,568 (range: 2,400–9,633) for TP53 and CTNNB1 variants, respectively. @*Conclusions@#Our targeted DNA sequencing successfully identified low-frequency pathogenic variants in the cfDNA from HCC patients by achieving high coverage of unique molecular families. Our results support the utility of cfDNA analysis to identify somatic gene variants in HCC patients.
ABSTRACT
Background@#The Bronchiectasis Health Questionnaire (BHQ) is a simple and repeatable, self-reporting health status questionnaire for bronchiectasis. We have translated the original version of the BHQ into Korean using a standardized methodology. The purpose of this study was to assess the validity of the Korean version of the BHQ (K-BHQ) with Korean patients. @*Methods@#Stable state patients with bronchiectasis from two academic hospitals were enrolled in this study. The validity was assessed by investigating the relationship between the K-BHQ scores and the Korean version of the Chronic Obstructive Pulmonary Disease Assessment Test (K-CAT) scores. We also investigated the relationship between the K-BHQ scores and other variables of the modified Medical Research Council’s (mMRC) dyspnea scale, lung function, and exacerbations. @*Results@#A total of 126 patients with bronchiectasis were enrolled. The mean age was 64.3 (standard deviation [SD], 9.7). Women comprised 53.2% of the patients. The mean forced expiratory volume in one second (FEV1) was 60% of the predicted value (SD, 18.9%); the mean K-CAT score was 17.6 (SD, 9.1). The K-BHQ scores correlated strongly with the K-CAT scores (r=–0.656, p<0.001). There was significant correlation between the K-BHQ scores and the mMRC dyspnea scale (ρ=–0.409, p<0.001), FEV1 (r=0.406, p<0.001), and number of exacerbations requiring hospitalization (ρ=–0.303, p=0.001). @*Conclusion@#The K-BHQ is valid for assessing the health-related quality of life or health status of Korean bronchiectasis patients.
ABSTRACT
Bronchiectasis refers to abnormal dilatation of the bronchi, which leads to the failure of mucus clearance and increased risk of infection. Pharmacotherapy for stable bronchiectasis includes oral or inhaled mucoactive agents, anti-inflammatory therapy, inhaled bronchodilators, long-term antibiotics, and long-term macrolide treatment.Among them, mucoactive agents are the most common adjunctive agents to airway clearance techniques. When patients with impaired lung function suffer from dyspnea, inhaled bronchodilators may be prescribed to relieve the symptom. Long-term macrolide treatment has been proven to prevent exacerbation in patients with frequent bronchiectasis exacerbation. If exacerbation occurs despite the above mentioned treatments, one or two weeks of antibiotics should be prescribed to cover respiratory bacteria that include Pseudomonas aeruginosa. Because evidence supporting the use of pharmacotherapy for bronchiectasis is weak, further research is warranted.
ABSTRACT
The impact of bronchiectasis on the occurrence of postoperative pulmonary complications (PPC) after extra-pulmonary surgery in patients with airflow limitation is not well elucidated. A retrospective analysis of 437 patients with airflow limitations, including 62 patients with bronchiectasis, was conducted. The analysis revealed that bronchiectasis was associated with increased PPC (adjusted odds ratio [aOR], 2.73; P = 0.001), which was especially significant in patients who did not use bronchodilators (aOR, 3.24; P = 0.002). Our study indicates that bronchiectasis is associated with an increased risk of PPC following extra-pulmonary surgery in patients with airflow limitation, and bronchodilators may prevent PPC in these patients.
ABSTRACT
The impact of bronchiectasis on the occurrence of postoperative pulmonary complications (PPC) after extra-pulmonary surgery in patients with airflow limitation is not well elucidated. A retrospective analysis of 437 patients with airflow limitations, including 62 patients with bronchiectasis, was conducted. The analysis revealed that bronchiectasis was associated with increased PPC (adjusted odds ratio [aOR], 2.73; P = 0.001), which was especially significant in patients who did not use bronchodilators (aOR, 3.24; P = 0.002). Our study indicates that bronchiectasis is associated with an increased risk of PPC following extra-pulmonary surgery in patients with airflow limitation, and bronchodilators may prevent PPC in these patients.
ABSTRACT
BACKGROUND: To validate the clinical application of chromosomal microarray analysis (CMA) as a first-tier clinical diagnostic test and to determine the impact of CMA results on patient clinical management, we conducted a multicenter prospective study in Korean patients diagnosed as having developmental delay/intellectual disability (DD/ID), autism spectrum disorders (ASD), and multiple congenital anomalies (MCA). METHODS: We performed both CMA and G-banding cytogenetics as the first-tier tests in 617 patients. To determine whether the CMA results directly influenced treatment recommendations, the referring clinicians were asked to complete a 39-item questionnaire for each patient separately after receiving the CMA results. RESULTS: A total of 122 patients (19.8%) had abnormal CMA results, with either pathogenic variants (N=65) or variants of possible significance (VPS, N=57). Thirty-five well-known diseases were detected: 16p11.2 microdeletion syndrome was the most common, followed by Prader-Willi syndrome, 15q11-q13 duplication, Down syndrome, and Duchenne muscular dystrophy. Variants of unknown significance (VUS) were discovered in 51 patients (8.3%). VUS of genes putatively associated with developmental disorders were found in five patients: IMMP2L deletion, PTCH1 duplication, and ATRNL1 deletion. CMA results influenced clinical management, such as imaging studies, specialist referral, and laboratory testing in 71.4% of patients overall, and in 86.0%, 83.3%, 75.0%, and 67.3% of patients with VPS, pathogenic variants, VUS, and benign variants, respectively. CONCLUSIONS: Clinical application of CMA as a first-tier test improves diagnostic yields and the quality of clinical management in patients with DD/ID, ASD, and MCA.
Subject(s)
Humans , Autism Spectrum Disorder , Autistic Disorder , Cytogenetics , Diagnostic Tests, Routine , Down Syndrome , Intellectual Disability , Korea , Microarray Analysis , Muscular Dystrophy, Duchenne , Prader-Willi Syndrome , Prospective Studies , Referral and Consultation , SpecializationABSTRACT
OBJECTIVES: Smoking and passive smoking have been extensively reported as risk factors of cardiovascular morbidity and mortality. Despite the biological mechanisms underlying the impact of hazardous chemical substances contained in tobacco in cardiovascular diseases (CVD), studies investigating the association between smoking and passive smoking with morbidity are at an inchoate stage in Korea. Therefore, this study aimed to estimate the risks of smoking and passive smoking on cardiovascular morbidity at the national and regional levels.METHODS: This study calculated sex-standardized and age-standardized prevalence of CVD and smoking indices in 253 community health centers (si/gun/gu) in Korea using the 2008-2013 Korea Community Health Survey data. Furthermore, a Bayesian hierarchical model was used to estimate the association of smoking and passive smoking with the prevalence of CVD from the national and regional community health centers.RESULTS: At the national level, smoking was significantly associated with stroke (relative risk [RR], 1.060) and hypertension (RR, 1.016) prevalence, whilst passive smoking at home and work were also significantly associated with prevalence of stroke (RR, 1.037/1.013), angina (RR, 1.016/1.006), and hypertension (RR, 1.010/1.004). Furthermore, the effects of smoking and passive smoking were greater in urban-industrial areas than in rural areas.CONCLUSIONS: The findings of this study would provide grounds for national policies that limit smoking and passive smoking, as well as regionally serve as the basis for region-specific healthcare policies in populations with high CVD vulnerability.
Subject(s)
Cardiovascular Diseases , Community Health Centers , Delivery of Health Care , Health Surveys , Hypertension , Korea , Mortality , Prevalence , Risk Factors , Smoke , Smoking , Stroke , Tobacco , Tobacco Smoke PollutionABSTRACT
OBJECTIVES: Smoking and passive smoking have been extensively reported as risk factors of cardiovascular morbidity and mortality. Despite the biological mechanisms underlying the impact of hazardous chemical substances contained in tobacco in cardiovascular diseases (CVD), studies investigating the association between smoking and passive smoking with morbidity are at an inchoate stage in Korea. Therefore, this study aimed to estimate the risks of smoking and passive smoking on cardiovascular morbidity at the national and regional levels. METHODS: This study calculated sex-standardized and age-standardized prevalence of CVD and smoking indices in 253 community health centers (si/gun/gu) in Korea using the 2008-2013 Korea Community Health Survey data. Furthermore, a Bayesian hierarchical model was used to estimate the association of smoking and passive smoking with the prevalence of CVD from the national and regional community health centers. RESULTS: At the national level, smoking was significantly associated with stroke (relative risk [RR], 1.060) and hypertension (RR, 1.016) prevalence, whilst passive smoking at home and work were also significantly associated with prevalence of stroke (RR, 1.037/1.013), angina (RR, 1.016/1.006), and hypertension (RR, 1.010/1.004). Furthermore, the effects of smoking and passive smoking were greater in urban-industrial areas than in rural areas. CONCLUSIONS: The findings of this study would provide grounds for national policies that limit smoking and passive smoking, as well as regionally serve as the basis for region-specific healthcare policies in populations with high CVD vulnerability.
Subject(s)
Cardiovascular Diseases , Community Health Centers , Delivery of Health Care , Health Surveys , Hypertension , Korea , Mortality , Prevalence , Risk Factors , Smoke , Smoking , Stroke , Tobacco , Tobacco Smoke PollutionABSTRACT
BACKGROUND: We describe the genetic profiles of Korean patients with glucose-6-phosphate dehydrogenase (G6PD) deficiencies and the effects of G6PD mutations on protein stability and enzyme activity on the basis of in silico analysis. METHODS: In parallel with a genetic analysis, the pathogenicity of G6PD mutations detected in Korean patients was predicted in silico. The simulated effects of G6PD mutations were compared to the WHO classes based on G6PD enzyme activity. Four previously reported mutations and three newly diagnosed patients with missense mutations were estimated. RESULTS: One novel mutation (p.Cys385Gly, labeled G6PD Kangnam) and two known mutations [p.Ile220Met (G6PD São Paulo) and p.Glu416Lys (G6PD Tokyo)] were identified in this study. G6PD mutations identified in Koreans were also found in Brazil (G6PD São Paulo), Poland (G6PD Seoul), United States of America (G6PD Riley), Mexico (G6PD Guadalajara), and Japan (G6PD Tokyo). Several mutations occurred at the same nucleotide, but resulted in different amino acid residue changes in different ethnic populations (p.Ile380 variant, G6PD Calvo Mackenna; p.Cys385 variants, Tomah, Madrid, Lynwood; p.Arg387 variant, Beverly Hills; p.Pro396 variant, Bari; and p.Pro396Ala in India). On the basis of the in silico analysis, Class I or II mutations were predicted to be highly deleterious, and the effects of one Class IV mutation were equivocal. CONCLUSIONS: The genetic profiles of Korean individuals with G6PD mutations indicated that the same mutations may have arisen by independent mutational events, and were not derived from shared ancestral mutations. The in silico analysis provided insight into the role of G6PD mutations in enzyme function and stability.
Subject(s)
Child , Child, Preschool , Humans , Male , Asian People/genetics , DNA/chemical synthesis , Exons , Glucosephosphate Dehydrogenase/chemistry , Glucosephosphate Dehydrogenase Deficiency/genetics , Mutation, Missense , Polymorphism, Genetic , Protein Structure, Tertiary , Republic of Korea , Sequence Analysis, DNAABSTRACT
Myeloproliferative neoplasms (MPNs) are clonal hematopoietic stem cell disorders characterized by the proliferation of one or more myeloid lineages. The current study demonstrates that three driver mutations were detected in 82.6% of 407 MPNs with a mutation distribution of JAK2 in 275 (67.6%), CALR in 55 (13.5%) and MPL in 6 (1.5%). The mutations were mutually exclusive in principle except in one patient with both CALR and MPL mutations. The driver mutation directed the pathologic features of MPNs, including lineage hyperplasia, laboratory findings and clinical presentation. JAK2-mutated MPN showed erythroid, granulocytic and/or megakaryocytic hyperplasia whereas CALR- and MPL-mutated MPNs displayed granulocytic and/or megakaryocytic hyperplasia. The lineage hyperplasia was closely associated with a higher mutant allele burden and peripheral cytosis. These findings corroborated that the lineage hyperplasia consisted of clonal proliferation of each hematopoietic lineage acquiring driver mutations. Our study has also demonstrated that bone marrow (BM) fibrosis was associated with disease progression. Patients with overt fibrosis (grade ⩾2) presented an increased mutant allele burden (P<0.001), an increase in chromosomal abnormalities (P<0.001) and a poor prognosis (P<0.001). Moreover, among patients with overt fibrosis, all patients with wild-type JAK2/CALR/MPL (triple-negative) showed genomic alterations by genome-wide microarray study and revealed the poorest overall survival, followed by JAK2-mutated MPNs. The genetic–pathologic characteristics provided the information for understanding disease pathogenesis and the progression of MPNs. The prognostic significance of the driver mutation and BM fibrosis suggests the necessity of a prospective therapeutic strategy to improve the clinical outcome.
Subject(s)
Humans , Alleles , Bone Marrow , Chromosome Aberrations , Disease Progression , Fibrosis , Hematopoietic Stem Cells , Hyperplasia , Prognosis , Prospective StudiesABSTRACT
PURPOSE: Direct sequencing (DS) is the standard method for detection of epidermal growth factor receptor (EGFR) gene mutation in non-small cell lung cancer (NSCLC); however, low detection sensitivity is a problem. The aim of this study is to demonstrate higher detection rate of EGFR gene mutation with peptide nucleic acid (PNA) clamping compared with DS. MATERIALS AND METHODS: This is a single arm, prospective study for patients with stage IIIB/IV or relapsed NSCLC. Using tumor DNA from 138 patients, both DS and PNA clamping for EGFR gene in exon 18, 19, 20, and 21 were performed. Discrepant results between the two methods were verified using Cobas and a mutant enrichment based next generation sequencing (NGS). Patients with activating mutations were treated with EGFR tyrosine kinase inhibitor (EGFR-TKI, gefitinib, or erlotinib) as first line treatment. RESULTS: Of 138 paired test sets, 24 (17.4%) and 45 (32.6%) cases with activating mutations were detected by DS and PNA clamping, respectively. The difference of detection rate between the two methods was 15.2% (95% confidence interval, 8.7% to 17.8%; p < 0.001). Between the two methods, 25 cases showed discrepant results (n=23, PNA+/DS-; n=2, PNA-/DS+). Mutations were confirmed by Cobas or NGS in 22 of 23 PNA+/DS- cases. The response rates to EGFR-TKI were 72.2% in the PNA+/DS+ group and 85.0% in the PNA+/DS- group. CONCLUSION: PNA clamping showed a significantly higher detection rate of EGFR gene mutation compared with DS. Higher sensitivity of PNA clamping was not compromised by the loss of predictive power of response to EGFR-TKI.