The mechanism of acquired resistance to irreversible EGFR tyrosine kinase inhibitor-afatinib in lung adenocarcinoma patients

Introduction

Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) are associated with favorable response in EGFR mutant lung cancer. Acquired resistance to reversible EGFR TKIs remains a significant barrier, and acquired EGFR T790M-mutation is the major mechanism. Second-generation irreversible EGFR TKI, afatinib, had also been approved for treating EGFR mutant lung cancer patients, but the mechanism of acquired resistance to afatinib has not been well studied.

Results

Forty-two patients had tissue specimens taken after acquiring resistance to afatinib. The sensitizing EGFR mutation were all consistent between pre- and post-afatinib tissues. Twenty patients (47.6%) had acquired T790M mutation. T790M rate was not different between first-generation EGFR TKI-naïve patients (50%) and first-generation EGFR TKI-treated patients (46.4%) (p = 0.827). No clinical characteristics or EGFR mutation types were associated with the development of acquired T790M. No other second-site EGFR mutations were detected. There were no small cell or squamous cell lung cancer transformation. Other genetic mutations were not identified in PIK3CA, BRAF, HER2, KRAS, NRAS, MEK1, AKT2, LKB1 and JAK2.

Methods

Afatinib-prescription record of our department of pharmacy from January 2007 and December 2014 was retrieved. We investigated patients with tissue specimens available after acquiring resistance to afatinib. Enrolled patients should have partial response or durable stable disease of treatment response to afatinib. Various mechanisms of acquired resistance to first-generation EGFR TKIs were evaluated. Histology and cytology were reviewed. EGFR, PIK3CA, BRAF, HER2, KRAS, NRAS, MEK1, AKT2, LKB1 and JAK2 genetic alterations were evaluated by sequencing. Statistical analysis was performed using Chi-square test and Kaplan-Meier method.

Conclusions

T790M was detected in half of the lung adenocarcinoma after acquiring resistance to afatinib. T790M is still the major acquired resistance mechanism. First-generation EGFR TKI exposure did not influence the prevalence of T790M in lung cancer acquired resistance to afatinib.

Combining MAD and CPAP as an effective strategy for treating patients with severe sleep apnea intolerant to high-pressure PAP and unresponsive to MAD

Introduction

This study aimed to determine the effect of combining positive airway pressure (PAP) therapy and mandibular advancement device (MAD) in patients with severe obstructive sleep apnea (OSA) who were pressure intolerant for PAP and were unresponsive to MAD.

Methods

This retrospective study reviewed the medical records of severe OSA patients with apnea-hypopnea index (AHI) ≥ 30/hr who were diagnosed between October 1, 2008 and June 30, 2014. Patients were initially treated with 2 weeks of PAP, and those who were intolerant to high-pressure PAP (≥15 cm H₂O) were switched to 12 weeks of MAD, which is a monobloc designed at 75% of maximum protrusion. Patients who had high residual AHI (≥15/hr) on MAD underwent 12 weeks of combination therapy (CT) with MAD and CPAP and were enrolled in the present study. Enrolled subjects who completed the 12-week CT were followed-up until June 30, 2016.

Results

A total of 14 male patients were included. All three treatments effectively reduced AHI, oxygen desaturation index (ODI), and total sleep time with SpO₂ <90% (% TST-SpO₂<90%) compared to pretreatment values. The residual AHI and ODI on CT was lower than that on MAD or PAP. The residual % TST-SpO₂<90% was lower than that on MAD and similar to that on PAP. The therapeutic pressure on CT was on average 9.2 cm H₂O lower than that on PAP. For the 11 patients who completed CT, only CT reduced ESS compared to pretreatment value. No treatment had significant impact on % slow wave sleep or overnight change of blood pressure. For patients who completed CT, the average usage was 5.9±1.7 hr/night at 12th week and 6.4±1.5 hr/night at a median follow-up of 36.5-months.

Conclusions

Combining MAD and CPAP showed additive effects on reducing AHI and ODI, and lowered the therapeutic pressures.

The value of repeat radial-probe endobronchial ultrasound-guided transbronchial biopsy after initial non-diagnostic results in patients with peripheral pulmonary lesions

Background

Radial-probe endobronchial ultrasound (rEBUS)-guided transbronchial biopsy (TBB) is invaluable in the diagnosis of peripheral pulmonary lesions (PPLs); however, in certain instances, the procedure has to be repeated because of initial non-diagnostic procedure(s). Little if any literature has been published on this issue. Therefore, the aim of this study was to investigate the utility of repeat rEBUS-guided TBB in achieving a definitive diagnosis of PPLs.

Methods

All patients who underwent rEBUS-guided TBB of PPLs at National Taiwan University Hospital between 2011 and 2015 and had a repeat procedure after non-diagnostic initial procedures were identified as the study subjects. The primary outcome of interest was the diagnostic yield of repeat rEBUS-guided TBB for PPLs. Also, we sought to discover features associated with the yield of repeat procedures.

Results

Forty-three (11%) out of 384 patients with initial non-diagnostic TBB were included for analysis. A diagnosis of PPLs was able to be confirmed with repeat TBB in 23(53%) patients. The pathology of the first TBB was significantly associated with the yield of repeat procedures (P = 0.011). Further, patients with normal lung tissue in initial pathology rarely (2/12, 17%) had a definite diagnosis on repeat TBB. Yet, patients with pathology showing atypical cells and other non-specific findings were more likely (21/31, 68%) to obtain a confirmed diagnosis. The diagnostic yield of repeat procedures was not affected by the size, location or CT appearance of the lesions, or position of the rEBUS probe. No death or other serious adverse events occurred with the repeat rEBUS-guided procedures.

Conclusions

If clinically indicated, it is reasonable to repeat rEBUS-guided TBB after an initial non-diagnostic procedure as the diagnostic yield will be at least 50% and the side effect profile is favorable.

Impact of selective and nonselective beta-blockers on the risk of severe exacerbations in patients with COPD

Background

There is conflicting information regarding the effects of selective and nonselective beta-blocker treatment in patients with COPD.

Participants and methods

This nested case–control study used the Taiwan National Health Insurance Research Database. We included COPD patients who used inhalation steroid and beta-blockers between 1998 and 2010. From this cohort, there were 16,067 patients with severe exacerbations included in the analysis and 55,970 controls matched on age, sex, COPD diagnosis year, and beta-blockers treatment duration by risk set sampling.

Results

For the selective beta-blocker users, the current users had a lower risk of severe exacerbations than the nonusers (odds ratio [OR], 0.90; 95% confidence interval [CI], 0.85–0.96). In contrast, for the nonselective beta-blocker users, the current users had a higher risk of severe acute exacerbations than the nonusers (OR, 1.21; 95% CI, 1.14–1.27). A higher risk of severe exacerbation during increasing mean daily dose or within about the initial 300 days was found in nonselective beta-blockers, but not in selective beta-blockers. One selective beta-blocker, betaxolol, had a significantly lower risk of severe exacerbations (OR, 0.75; 95% CI, 0.60–0.95). Two nonselective beta-blockers (labetalol and propranolol) were associated with a significantly higher risk of exacerbations (OR, 1.49; 95% CI, 1.32–1.67 for labetalol; OR, 1.16; 95% CI, 1.10–1.23 for propranolol).

Conclusion

Selective beta-blockers can be cautiously prescribed for patients with COPD and cardiovascular disease (CVD), however, nonselective beta-blockers should not be prescribed for patients with COPD. Betaxolol may be the preferred choice of suitable selective beta-blocker for patients with COPD, however, labetalol and propranolol should be avoided for patients with COPD.

Psychological distress and coping strategies among women with incurable lung cancer: a qualitative study

PURPOSE

Limited research has focused on women with lung cancer (LC) although they are recognized as the most vulnerable to psychological distress. This study explored in-depth the psychological distress experienced by women with incurable LC and analyzed the coping strategies with which they manage that distress.

METHODS

A qualitative methodology with in-depth interviews was employed for 34 women with advanced or recurrent LC. An inductive data-driven thematic analysis was applied to analyze transcripts.

RESULTS

Psychological distress was an iterative process for the women. Four themes were identified: shock regarding the diagnosis, distress regarding cancer treatment and its side effects, the facing of a recurrent or progressive disease, and persistent struggle with the life-limiting disease. Various coping strategies applied by the women to manage psychological distress were grouped into four themes: relying upon social support, focusing on positive thoughts, avoidance-based strategies, and religious faith and acceptance.

CONCLUSIONS

Women with incurable LC experienced substantial iterative psychological distress throughout the illness, regardless of length of illness at time of interview. They applied multiple forms of coping. The findings enrich the limited existing literature on this understudied population and provide direction for the future development of interventions to improve their psychological well-being.

Severe exacerbation and pneumonia in COPD patients treated with fixed combinations of inhaled corticosteroid and long-acting beta2 agonist

BACKGROUND

It remains unclear whether severe exacerbation and pneumonia of COPD differs between patients treated with budesonide/formoterol and those treated with fluticasone/salmeterol. Therefore, we conducted a comparative study of those who used budesonide/formoterol and those treated with fluticasone/salmeterol for COPD.

METHODS

Subjects in this population-based cohort study comprised patients with COPD who were treated with a fixed combination of budesonide/formoterol or fluticasone/salmeterol. All patients were recruited from the Taiwan National Health Insurance database. The outcomes including severe exacerbations, pneumonia, and pneumonia requiring mechanical ventilation (MV) were measured.

RESULTS

During the study period, 11,519 COPD patients receiving fluticasone/salmeterol and 7,437 patients receiving budesonide/formoterol were enrolled in the study. Pairwise matching (1:1) of fluticasone/salmeterol and budesonide/formoterol populations resulted in to two similar subgroups comprising each 7,295 patients. Patients receiving fluticasone/salmeterol had higher annual rate and higher risk of severe exacerbation than patients receiving budesonide/formoterol (1.2219/year vs 1.1237/year, adjusted rate ratio, 1.08; 95% CI, 1.07-1.10). In addition, patients receiving fluticasone/salmeterol had higher incidence rate and higher risk of pneumonia than patients receiving budesonide/formoterol (12.11 per 100 person-years vs 10.65 per 100 person-years, adjusted hazard ratio [aHR], 1.13; 95% CI, 1.08-1.20). Finally, patients receiving fluticasone/salmeterol had higher incidence rate and higher risk of pneumonia requiring MV than patients receiving budesonide/formoterol (3.94 per 100 person-years vs 3.47 per 100 person-years, aHR, 1.14; 95% CI, 1.05-1.24). A similar trend was seen before and after propensity score matching analysis, intention-to-treat, and as-treated analysis with and without competing risk.

CONCLUSIONS

Based on this retrospective observational study, long-term treatment with fixed combination budesonide/formoterol was associated with fewer severe exacerbations, pneumonia, and pneumonia requiring MV than fluticasone/salmeterol in COPD patients.

[RNA interference targeting DNA-PKcs inhibits glioma cells malignancies and enhances temozolomide sensitivity]

Objective: To investigate the effect of DNA dependent protein kinase catalytic subunit (DNA-PKcs) on glioma proliferation, invasion and temozolomide sensitivity, and also to explore the potential mechanisms. Methods: Human glioma cell lines H4 and U87 were chosen to carry out RNA interference transfection, and then divided into negative control group (blank group) and siRNA group (test group). The knockdown efficacy of DNA-PKcs siRNA was tested by quantitative PCR and Western blot. The MTS assay and Transwell assay were used to investigate the effect of DNA-PKcs knockdown on glioma cell growth and invasion, respectively. We also used MTS assay to investigate the IC(50) value of temozolomide in negative control group and siRNA groups. Result: Compared with blank group, DNA-PKcs specific siRNA significantly downregulated both mRNA and protein level of DNA-PKcs. MTS assay results demonstrated that 72-hours proliferation of test group were only 52.48%, 54.70% (H4) and 52.98%, 50.45% (U87) of the blank group's counterpart. Transwell assay results showed that the invasiveness abilities of blank and test groups were 1.00±0.03, 0.41±0.05, 0.39±0.04 (H4) and 1.00±0.02, 0.28±0.04, 0.27±0.04 (U87). Moreover, knockdown of DNA-PKcs significantly decreased the temozolomide IC(50) value (H4: 249±27, 97±39, 88±35; U87: 485±41, 86±49, 73±38). Further we applied the Western blot to reveal the mechanism of inhibitory effect of DNA-PKcs knockdown on glioma malignancies and temozolomide sensitivity. We found that downregulation of DNA-PKcs reduced the activity of AKT signal and the expression of its downstream effectors, such as c-Myc, MMP9, and Survivin. Conclusion: RNA interference targeting DNA-PKcs could inhibit glioma malignancies and enhance temozolomide sensitivity. The inhibitory effect of DNA-PKcs knockdown on those biological activities were mainly through inhibition of AKT signal and its downstream effectors.

The identification of the TRPM8 channel on primary culture of human nasal epithelial cells and its response to cooling

BACKGROUND

It has been proposed that the transient receptor potential (TRP) channel Melastatin 8 (TRPM8) is a cold-sensing TRP channel. However, its presence and its role in the nasal cavity have not yet been fully studied.

METHODS

Immunohistology was used to study TRPM8 receptors in both the nasal mucosa tissue and the primary cultures of human nasal cells. Cells from primary cultures were immunostained with antibodies to TRPM8, mucin, cytokeratin (CK)-14, CK-18, and vimentin. Western blotting and real-time polymerase chain reaction (PCR) were used to determine the physiological role of TRPM8 in mucus production in the nasal cavity, with and without its agonist and antagonist.

RESULTS

The TRPM8 is clearly present in the epithelium, mucous glands, and vessels. No obvious TRPM8-immunoreactive cells were detected in the connective tissue. Immunostaining of cytospin preparations showed that epithelial cells test positive for CK-14, CK-18, TRPM8, and mucin 5AC (MUC5AC). Fibroblastic cells are stained negative for TRPM8. Secreted mucins in the cultured supernatant are detected after exposure to menthol and moderate cooling to 24°C. Both induce a statistically significant increase in the level of MUC5AC mRNA and mucin production. BCTC, a TRPM8 antagonist, has a statistically significant inhibitory effect on MUC5AC mRNA expression and MUC5AC protein production that is induced by menthol and moderate cooling to 24°C.

CONCLUSIONS

The study demonstrates that TRPM8 is present in the nasal epithelium. When it is activated by moderate cooling to 24°C or menthol, TRPM8 induces the secretion of mucin. This study shows that TRPM8 channels are important regulators of mucin production. Therefore, TRPM8 antagonists could be used to treat refractory rhinitis.

Lung adenocarcinoma patients of young age have lower EGFR mutation rate and poorer efficacy of EGFR tyrosine kinase inhibitors

Patients aged ≤50 years are rarely diagnosed with nonsmall cell lung cancer. We conducted a retrospective cohort study to understand the mutation status of EGFR and the efficacy of epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) treatment in young Asian patients with lung adenocarcinoma.

We collected tumour specimens and malignant pleural effusions from lung adenocarcinoma patients from June 2005 to April 2014, recorded their clinical demographic data, and analysed EGFR mutations by reverse transcriptase PCR.

EGFR mutation data were collected from 1039 lung adenocarcinoma patients, including 161 patients aged ≤50 years and 878 patients aged >50 years. Fewer patients aged ≤50 years had EGFR mutations than older patients (p=0.043), but they showed a higher rate of uncommon EGFR mutations (p=0.035). A total of 524 patients with EGFR mutations received EGFR-TKI treatment, including 81 patients aged ≤50 years. Younger patients had a lower response rate than older patients (p=0.038) and had the shortest progression-free survival compared with other predefined age categories (p=0.033). Multivariate analysis of overall survival revealed age ≤50 years as a poor prognostic factor.

In conclusion, fewer Asian patients aged ≤50 years had EGFR mutations, but the EGFR mutation types were more uncommon. Age ≤50 years is associated with poorer efficacy of EGFR-TKI treatment.

Association between age and EGFR mutationshttp://ow.ly/jV4n30bRBUX

Clinical characteristics of bacteraemia caused by Burkholderia cepacia complex species and antimicrobial susceptibility of the isolates in a medical centre in Taiwan

This study investigated the clinical characteristics and outcomes of bacteraemia due to Burkholderia cepacia complex (BCC) species among 54 patients without cystic fibrosis from January 2013 to February 2015. BCC isolates were identified to the species level by the Bruker Biotyper MALDI-TOF MS system and by sequencing analysis of the 16S rRNA and recA genes. Antimicrobial susceptibilities of the isolates were determined by the agar dilution method. Sequencing of the recA gene in the 54 blood isolates revealed 37 (68.5%) isolates of B. cenocepacia, 9 (16.7%) of B. cepacia, 4 (7.4%) of B. multivorans and one isolate each of B. arboris, B. pseudomultivorans, B. seminalis, and B. vietnamiensis. The overall performance of the Bruker Biotyper MALDI-TOF MS system for correctly identifying the 54 BCC isolates to the species level was 79.6%, which was better than that (16.7%) by 16S RNA sequencing analysis. Bacteraemic pneumonia (n = 23, 42.6%) and catheter-related bacteraemia (n = 21, 38.9%) were the most common types of infection. Higher rates of ceftazidime and meropenem resistance were found in B. cepacia isolates (33.3% and 22.2%, respectively) than in isolates of B. cenocepacia (21.6% and 10.8%, respectively) and other species (12.5% and 12.5%, respectively). Overall, the 30-day mortality rate was 38.9% (21/54). Bacteraemia caused by BCC species other than B. cenocepacia and B. cepacia (adjusted odds ratio [aOR] 20.005, P = 0.024) and high SOFA score (aOR 1.412, P = 0.003) were predictive of higher 30-day mortality. Different BCC species are associated with different outcomes of bacteraemia and exhibit different susceptibility patterns.

Outcomes of cancer therapy administered to treatment-naïve lung cancer patients in the intensive care unit

Objectives: Therapy outcomes for newly diagnosed, critically ill lung cancer patients have seldom been evaluated. This study evaluated therapy outcomes for treatment-naïve lung cancer patients in the intensive care unit (ICU). Materials and Methods: Patients were excluded if they had previously received lung cancer treatment, such as systemic chemotherapy, targeted therapy, radiotherapy, or surgical lung resection before ICU admission. The therapeutic strategies for the treatment-naïve patients were determined while they were in the ICU. The patients' demographic data, clinical outcomes, and treatment-related toxicities were analyzed. Results: Newly diagnosed lung cancer patients (n = 72) who did not receive any anticancer treatment before ICU admission were included. Most patients had locally advanced disease, and 61 (84.7%) required intensive care due to cancer-related events. In the ICU, 24 (33.3%) patients received chemotherapy, 24 (33.3%) received epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) therapy and 24 (33.3%) received best supportive care (BSC). Patients receiving chemotherapy or EGFR-TKIs in the ICU demonstrated better ICU (p = 0.011) and in-hospital (p = 0.034) survival than those receiving BSC only. Among patients requiring mechanical ventilation, those receiving chemotherapy had higher weaning rates than those receiving EGFR-TKIs or BSC (p = 0.002). In multivariate analysis, receipt of chemotherapy (hazard ratio [HR], 0.443; p = 0.083) and mechanical ventilation (HR, 0.270; p = 0.022) were significantly associated with longer ICU survival after adjusting for clinical factors. Conclusions: Anticancer therapy in the ICU might provide better short-term ICU survival for treatment-naïve, critically ill lung cancer patients.

Abstract 538: The cytosolic domain of a disintergrin and metalloprotease (ADAM) 15 promotes non-small cell lung cancer (NSCLC) anti-apoptosis ability

Emerging evidence has indicated that proteins of a disintergrin and metalloprotease (ADAM) family contribute to cancer progression and metastasis. One member of this family, ADAM15, has been shown to be upregulated in multiple cancers, including gastric, lung, breast, and prostate cancers, and the enzymatic activities of its extracellular metalloprotrease domain promote breast cancer proliferation and migration through mediating ErbB signaling pathway. The patients with ADAM15 high-expressing lung tumors have shorter survival time and ADAM15 has been proved to enhance synovial fibroblasts anti-apoptosis ability via focal adhesion kinase signaling pathway. We firstly demonstrated other than extracellular enzymetic activity, the longest isoform of ADAM15 (ADAM15 i6), which contains the most cytoplasmic Src homology 3 (SH3) binding motifs, significantly upregulated in primary lung cancer tissues and promoted NSCLC proliferation via growth factor receptor-bound protein 2 (Grb2) and Src homolog 2 domain containing (Shc) association. In this study, we further explore the roles of ADAM15 cytosolic domain in NSCLC apoptosis resistance. Overexpression of ADAM15 i6 promoted CL1-0 cell anti-apoptosis ability according to the trypan blue inclusion assay. Ablation of nephrocystin (NPHP1) attenuated the ADAM15 i6-promoted anti-apoptosis ability. Thus, we identified a novel mechanism of the ADAM15 cytoplasmic domain in NSCLC tumor progression, which will shed light on the molecular mechanisms of ADAM proteins, and facilitate development of novel therapy in NSCLC.

Note: This abstract was not presented at the meeting.

Citation Format: Hsin-Han Hou, Chong-Jen Yu. The cytosolic domain of a disintergrin and metalloprotease (ADAM) 15 promotes non-small cell lung cancer (NSCLC) anti-apoptosis ability [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 538. doi:10.1158/1538-7445.AM2017-538

Decreased T helper 17 cells in tuberculosis is associated with increased percentages of programmed death ligand 1, T helper 2 and regulatory T cells

Background

Tuberculosis (TB) is one of the most common infectious diseases worldwide. During active tuberculosis, T helper (Th) 17 cells are decreased, however the association with inhibitory immune regulation is unclear.

Methods

We enrolled 27 patients with TB and 20 age- and sex-matched controls and studies their lymphocyte status. Peripheral blood lymphocytes were isolated and programmed death-1 (PD-1) and programmed death ligand 1 (PD-L1) were measured on Th17 cells by using flow cytometry after the cells were stimulated with phorbol 12-myristate 13-acetate and ionomycin for 6 h. In addition, Th2 and regulatory T cells were measured and analyzed.

Results

The TB group had lower levels of Th17 cells but higher levels of Th2 and Treg cells than the controls. In Th17 cells, the percentage of PD-L1 was higher in the TB group than that in the controls. In Th2 and Treg cells, the percentage of cytotoxic T-lymphocyte associated protein 4 (CTLA-4) was lower in the TB group and PD-1 was higher in Treg cells in the TB group. In the patients with extra-pulmonary TB, levels of Th1, Th2 and T17 cells were lower than those with pulmonary TB. The percentage of PD-1 on Th1 lymphocytes positively correlated with radiographic score.

Conclusions

Lower level of Th17 in TB patients may be associated with increased percentage of PD-L1 and increasing levels of Th2 and Treg cells which influenced by CTLA-4.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-017-0580-3) contains supplementary material, which is available to authorized users.

Gefitinib or erlotinib in previously treated non-small-cell lung cancer patients: a cohort study in Taiwan

Among treatment modalities for lung cancer, the most promising therapy is the use of epidermal growth factor receptor tyrosine kinase inhibitors (EGFR‐TKIs). Both erlotinib and gefitinib, the two first‐generation EGFR‐TKIs, exhibit significant clinical responses for patients with lung adenocarcinoma. However, few studies have compared the effects of these two drugs, and results have been inconclusive because of the small sample sizes in these studies. Therefore, this study was conducted to investigate this issue. This retrospective nationwide cohort study enrolled NSCLC patients who received EGFR‐TKIs after previous chemotherapy in Taiwan between 1996 and 2010 from the National Health Insurance Research Database. Clinical response and survival after receiving erlotinib and gefitinib were compared using logistic and Cox regression analyses, respectively. Inverse propensity score weighting and a sensitivity analysis in the EGFR‐TKI responder (clinical improvement by taking EGFR‐TKIs for 90 days), adherent patients (receiving EGFR‐TKI on a daily basis), adenocarcinoma, and adenocarcinoma with second‐line TKIs subgroup were performed for bias adjustment. A total of 7222 patients, including 4592 (63.6%) who received gefitinib, were identified. In the survival analysis, erlotinib was associated with a decline in 1‐year progression‐free survival (PFS) (hazard ratio, HR: 1.15 [1.09–1.21]) and overall survival (OS) (HR: 1.10 [1.03–1.18]). The effects of various TKIs were consistent in the 4939 EGFR‐TKI responders, adherent subgroup, adenocarcinoma subgroup, and adenocarcinoma with second‐line TKIs subgroup. In previously treated EGFT‐TKI‐naive NSCLC patients, those receiving gefitinib exhibited a longer PFS and OS than those receiving erlotinib. Additional large‐scale randomized controlled trials are warranted to confirm this finding.

Experience improves the performance of endobronchial ultrasound-guided transbronchial biopsy for peripheral pulmonary lesions: A learning curve at a medical centre

Background

Endobronchial ultrasound(EBUS)-guided transbronchial biopsy(TBB) is the preferred diagnostic tool for peripheral pulmonary lesions(PPLs) and mastering this procedure is an important task in the training of chest physicians. Little has been published about the learning experience of physicians with this technique, particularly at an institutional level. We aimed to establish a learning curve for EBUS-guided TBB for PPLs at a medical center.

Methods

Between 2008 and 2015, consecutive patients with PPLs referred for EBUS-guided TBB at National Taiwan University Hospital were enrolled. To build the learning curve, the diagnostic yield of TBB (plus brushings and washings) was calculated and compared. Meanwhile, lesion characteristics, and procedure-related features and complications were obtained to analyze associations with TBB yield and safety profile.

Results

A total of 2144 patients were included and EBUS-guided TBB was diagnostic for 1547(72%). The TBB yield was 64% in 2008 and reached a plateau of 72% after 2010. It took approximately 400 EBUS-guided procedures to achieve stable proficiency. Further analysis showed that improvement in diagnostic yield over time was mainly observed in PPLs, in cases in which the diameter was ≤2 cm or the EBUS probe could not be positioned within. Complication rates were low, with 1.8% and 0.5% for pneumothorax and hemorrhage, respectively.

Conclusions

Even though EBUS-guided TBB is an easy-to-learn technique, it takes 3 years or around 400 procedures for a medical center to achieve a better and stable performance. In particular, the diagnostic yield for lesions without the probe within or those sized ≤2 cm could improve with time.

IGFBP-7 to confer resistance to the epidermal growth factor receptor tyrosine kinase inhibitor

e20572

Background: Lung cancer is a leading cause of cancer death worldwide. The EGFR mutation-positive patients of lung adenocarcinoma had dramatic response to EGFR tyrosine kinase inhibitors (TKIs). However, acquired drug resistance developed invariably after one year treatment course of EGFR TKI. IGFBP-7, a secreted 31 kDa protein, exhibits low affinity for IGF but binds strongly to insulin. No previous studies had been mentioned the correlation between the protein and acquired EGFR TKI resistance. Methods: cDNA microarray was used to screen differentially expressed genes between EGFR TKI-sensitive (PC9 and HCC827) and acquired EGFR TKIs-resistance cell lines (PC9/gef and HCC827/gef). The expression levels of the screened genes were validated by RT -PCR and Western blot analysis. Molecular manipulations (silencing or overexpression) were performed to investigate the effects of IGFBP-7 on gefitinib resistance in vitro. In addition, clinical specimens were collected to validate the imact of IGFBP-7 on the efficacy of EGFR TKI treatment . Results: IGFBP-7 is over-expressed in gefitinib-resistant cells. The IGFBP-7 mRNA expression in the malignant pleural effusion of patients with acquired resistance to EGFR TKI was significant higher than that in the treatment-naïve patients. Knockdown IGFBP-7 reverses gefitinib resistance in PC9/gef cells. Knockdown IGFBP-7 could increase gefetinib induced-apoptosis through the regulation of BIM. IGFBP-7 affected the mechanism of EGFR TKI resistance resulted from inhibition of IGF-IR.. In clinical practice, low IGFBP-7 serum level is associated with longer progression free survival (PFS) of EGFR TKI as the first line treatment. Furthermore, lower IGFBP-7 level of resected tumor predicts a longer 5-year tumor relapse-free survival. Positive IGFBP-7 immunoihistochemical stain could predict a shorter PFS of the first-line EGFR TKI treatment. Conclusions: IGFBP-7 confers resistance to the EGFR TKI and may be a target for future treatment investigation.

Real-World Data on Prognostic Factors for Overall Survival in EGFR Mutation-Positive Advanced Non-Small Cell Lung Cancer Patients Treated with First-Line Gefitinib

BACKGROUND

This study aimed to identify independent prognostic factors for overall survival (OS) of patients with advanced non-small cell lung cancer (NSCLC) harboring an activating epidermal growth factor receptor (EGFR) mutation and receiving gefitinib as first-line treatment in real-world practice.

MATERIALS AND METHODS

We enrolled 226 patients from June 2011 to May 2013. During this period, gefitinib was the only EGFR-tyrosine kinase inhibitor reimbursed by the Bureau of National Health Insurance of Taiwan.

RESULTS

The median progression-free survival and median OS were 11.9 months (95% confidence interval [CI]: 9.7-14.2) and 26.9 months (21.2-32.5), respectively. The Cox proportional hazards regression model revealed that postoperative recurrence, performance status (Eastern Cooperative Oncology Grade [ECOG] ≥2), smoking index (≥20 pack-years), liver metastasis at initial diagnosis, and chronic hepatitis C virus (HCV) infection were independent prognostic factors for OS (hazard ratio [95% CI] 0.3 [0.11-0.83], p = .02; 2.69 [1.60-4.51], p < .001; 1.92 [1.24-2.97], p = .003; 2.26 [1.34-3.82], p = .002; 3.38 [1.85-7.78], p < .001, respectively). However, brain metastasis (BM) at initial diagnosis or intracranial progression during gefitinib treatment had no impact on OS (1.266 [0.83-1.93], p = .275 and 0.75 [0.48-1.19], p = .211, respectively).

CONCLUSION

HCV infection, performance status (ECOG ≥2), newly diagnosed advanced NSCLC without prior operation, and liver metastasis predicted poor OS in EGFR mutation-positive advanced NSCLC patients treated with first-line gefitinib; however, neither BM at initial diagnosis nor intracranial progression during gefitinib treatment had an impact on OS.

IMPLICATIONS FOR PRACTICE

The finding that chronic hepatitis C virus (HCV) infection might predict poor overall survival (OS) in epidermal growth factor receptor mutation-positive advanced non-small cell lung cancer (NSCLC) patients treated with first-line gefitinib may raise awareness of benefit from anti-HCV treatment in this patient population. Brain metastasis in the initial diagnosis or intracranial progression during gefitinib treatment is not a prognostic factor for OS. This study, which enrolled a real-world population of NSCLC patients, including sicker patients who were not eligible for a clinical trial, may have impact on guiding usual clinical practice.

Expression of Notch Gene and Its Impact on Survival of Patients with Resectable Non-small Cell Lung Cancer

BACKGROUND: Notch signaling has been demonstrated to frequently participate in the process of lung carcinogenesis. This study aimed to search Notch expression in non-small cell lung cancer (NSCLC) and its impact on survival.

METHODS: From 2001 to 2011, patients with diagnosis of NSCLC who received surgical resection were included. The expression of Notch gene was assessed by real-time polymerase chain reaction (RT-PCR). Clinical characteristics, histological types, disease stages, and outcomes were analyzed.

RESULTS: Ninety-seven patients with NSCLC being explored the expression of Notch gene (Notch1 - 4). Seventy-five patients (77.3%) were adenocarcinoma. Patients with adenocarcinoma had higher expression of Notch2 than other histology types (p < 0.001). Otherwise, patients with squamous cell carcinoma had relative higher expression of Notch1 and Notch3 expression (p = 0.014 and p = 0.032, respectively). Notch2 expression increased associated with patients with more advanced lung cancer stage. Patients who had cancer recurrence also had higher Notch2 expression (p = 0.008). The patient group with lung adenocarcinoma of both high Notch1 and Notch3 expression had a shorter median disease-free survival (DFS) (both high v.s both low: DFS, median, 7.2 v.s 25.3 months, p = 0.03). However, the expression of Notch gene had no impact on overall survival.

CONCLUSIONS: Patients with lung adenocarcinoma had higher Notch2 expression. Patients with higher Notch2 expression also had higher rate of cancer recurrence. Both higher Notch1 and Notch3 expression was associated with poor prognosis in lung adenocarcinoma.

Outcomes of research biopsies in clinical trials of EGFR mutation-positive non-small cell lung cancer patients pretreated with EGFR-tyrosine kinase inhibitors

BACKGROUND/PURPOSE

Research biopsies (RBs) are crucial for developing novel molecular targeted agents. However, the safety and diagnostic yields of RBs have not been investigated in EGFR mutation-positive non-small cell lung cancer (NSCLC) patients pretreated with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs).

METHODS

We searched the medical records of NSCLC patients who participated in lung cancer clinical trials and underwent mandatory RBs between 2012 and 2014 at our institution. Only patients with EGFR mutation-positive NSCLC pretreated with at least 1 EGFR-TKI were enrolled.

RESULTS

Of 140 enrolled patients, 73 (52.1%) and 59 (42.1%) had exon 19 deletions and exon 21 L858R mutation, respectively. Before RBs, 108 (77.1%), 83 (59.3%), and 36 (25.7%) patients had been treated with gefitinib, erlotinib, and afatinib, respectively. Computed tomography-guided percutaneous core needle biopsy was the most frequently used modality among 181 RBs performed (50.8%), followed by ultrasonography-guided (32.0%) and endoscopic RBs (16.0%). The most common RB sites were the lung (69.6%), pleura (8.8%), and liver (6.1%). Pathologic examinations revealed malignant cells in most RB specimens (72.9%). Complications due to RBs included pneumothorax (11.6%), bleeding (6.1%), and infection (1.1%). Only 1 patient required chest tube placement for pneumothorax, and 2 patients underwent endotracheal intubation because of bleeding.

CONCLUSION

RBs in this patient population were generally safe. Pneumothorax was the most frequent complication; bleeding, while infrequent, increased the risk of severe events. The diagnostic yields and complications of any particular modality should therefore be discussed with prospective clinical trial participants.

Diabetes mellitus in patients with chronic obstructive pulmonary disease-The impact on mortality

Background

Chronic obstructive pulmonary disease (COPD) is the leading cause of morbidity and mortality worldwide. There is evidence to support a connection between COPD and diabetes mellitus (DM), another common medical disorder. However, additional research is required to improve our knowledge of these relationships and their possible implications. In this study, we investigated the impact of DM on patient outcomes through the clinical course of COPD.

Methods

We conducted a cohort study in patients from the Taiwan Longitudinal Health Insurance Database between 2000 and 2013. Patients with COPD were identified and assessed for pre-existing and incident DM. A Cox proportional hazards model was built to identify factors associated with incident DM and to explore the prognostic effects of DM on COPD patients. A propensity score method was used to match COPD patients with incident DM to controls without incident DM.

Results

Pre-existing DM was present in 332 (16%) of 2015 COPD patients who had a significantly higher hazard ratio (HR) [1.244, 95% confidence interval (CI) 1.010–1.532] for mortality than that of the COPD patients without pre-existing DM. During the 10-year follow-up period, 304 (19%) of 1568 COPD patients developed incident DM; comorbid hypertension (HR, 1.810; 95% CI, 1.363–2.403), cerebrovascular disease (HR, 1.517; 95% CI, 1.146–2.008) and coronary artery disease (HR, 1.408; 95% CI 1.089–1.820) were significant factors associated with incident DM. Survival was worse for the COPD patients with incident DM than for the matched controls without incident DM (Log-rank, p = 0.027).

Conclusions

DM, either pre-existing or incident, was associated with worse outcomes in COPD patients. Targeted surveillance and management of DM may be important in clinical care of the COPD population.

Diabetes Mellitus and Latent Tuberculosis Infection: A Systematic Review and Metaanalysis

Background

Despite the well-documented association between diabetes and active tuberculosis, evidence of the association between diabetes and latent tuberculosis infection (LTBI) remains limited and inconsistent.

Methods

We included observational studies that applied either the tuberculin skin test or the interferon gamma release assay for diagnosis of LTBI and that provided adjusted effect estimate for the association between diabetes and LTBI. We searched PubMed and EMBASE through 31 January 2016. The risk of bias of included studies was assessed using a quality assessment tool modified from the Newcastle-Ottawa scale.

Results

Thirteen studies (1 cohort study and 12 cross-sectional studies) were included, involving 38263 participants. The cohort study revealed an increased but nonsignificant risk of LTBI among diabetics (risk ratio, 4.40; 95% confidence interval [CI], 0.50-38.55). For the cross-sectional studies, the pooled odds ratio from the random-effects model was 1.18 (95% CI, 1.06-1.30), with a small statistical heterogeneity across studies (I2, 3.5%). The risk of bias assessment revealed several methodological issues, but the overall direction of biases would reduce the positive causal association between diabetes and LTBI.

Conclusions

Diabetes was associated with a small but statistically significant risk for LTBI. Findings from this review could be used to inform future cost-effectiveness analysis on the impact of LTBI screening programs among diabetics.