How can we optimise concurrent chemoradiotherapy for inoperable stage III non-small cell lung cancer?

Gemcitabine enhances pharmacokinetic exposure of the major components of Danggui Buxue Decoction in rat via the promotion of intestinal permeability and down-regulation of CYP3A for combination treatment of non-small cell lung cancer

CONTEXT

Danggui Buxue Decoction (DBD), a traditional Chinese medicine formula, has the potential to enhance the antitumor effect of gemcitabine in non-small cell lung cancer (NSCLC) treatment by increasing gemcitabine's active metabolites. However, whether gemcitabine affects the pharmacokinetics of DBD's major components remains unclear.

OBJECTIVE

This study evaluates the herb-drug interaction between DBD's major components and gemcitabine and validates the underlying pharmacokinetic mechanism.

MATERIALS AND METHODS

The pharmacokinetics of 3.6 g/kg DBD with and without a single-dose administration of 50 mg/kg gemcitabine was investigated in Sprague-Dawley rats. The effects of gemcitabine on intestinal permeability, hepatic microsomal enzymes in rat tissues, and CYP3A overexpressing HepG2 cells were determined using western blot analysis.

RESULTS

The combination of gemcitabine significantly altered the pharmacokinetic profiles of DBD's major components in rats. The Cmax and AUC of calycosin-7-O-β-d-glucoside notably increased through sodium-glucose transporter 1 (SGLT-1) expression promotion. The AUC of ligustilide and ferulic acid was also significantly elevated with the elimination half-life (t1/2) prolonged by 2.4-fold and 7.8-fold, respectively, by down-regulating hepatic CYP3A, tight junction proteins zonula occludens-1 (ZO-1) and occludin expression.

DISCUSSION AND CONCLUSIONS

Gemcitabine could modulate the pharmacokinetics of DBD's major components by increasing intestinal permeability, enhancing transporter expression, and down-regulating CYP3A. These findings provide critical information for clinical research on DBD as an adjuvant for NSCLC with gemcitabine and help make potential dosage adjustments more scientifically and rationally.

Consolidation treatments after chemoradiotherapy in patients with locally advanced inoperable non-small cell lung cancer: a systematic review and network meta-analysis protocol

INTRODUCTION

Concurrent chemoradiotherapy (CCRT) is the standard of care for inoperable locally advanced non-small cell lung cancer. To further improve prognosis, the use of consolidation treatments after CCRT has been explored extensively. Although durvalumab is the only consolidation treatment recommended by national clinical practice guidelines, there have been many studies exploring the effectiveness of other agents. However, until now, no studies have compared all agents systematically, and no studies have provided evidence for the optimal combination of different CCRTs and consolidation treatments regimens. This systematic review will evaluate the comparative clinical efficacy of consolidation therapies after CCRT as well as various combinations of CCRTs and consolidation therapies.

METHODS AND ANALYSIS

PubMed, the Cochrane Controlled Register of Trials (CENTRAL), EMBASE and ClinicalTrials.gov will be searched for relevant information. The estimated end date for the search will be 3 February 2022. Each stage of the review, including the study section, data extraction and risk of bias and quality of evidence assessments, will be performed in duplicate. We will include randomised controlled trials that included participants who received CCRT and consolidation treatment in at least one treatment arm. The primary endpoints will be overall survival and progression-free survival. Tumour response, health-related quality of life, disease-free survival and treatment-related toxicity will be presented as secondary outcomes. Both traditional meta-analysis and network meta-analysis (NMA) with the Bayesian approach will be conducted. Subgroup analyses and meta-regression will be completed to investigate heterogeneity, and sensitivity analyses will be conducted to assess the robustness of the findings.

ETHICS AND DISSEMINATION

Ethical approval and patient consent are not required as this study is a meta-analysis based on published studies. The results of this study will be submitted to a peer-reviewed journal for publication. In case of any changes in the protocol, protocol amendments will be updated in PROSPERO and explanations of these modifications will be described in the final report of this review. The results of this systematic review and NMA will be published in a peer-reviewed journal.

PROSPERO REGISTRATION NUMBER

CRD42021239433.

Systemic and Radiation Therapy Approaches for Locally Advanced Non-Small-Cell Lung Cancer

The treatment for locally advanced non-small-cell lung cancer has changed dramatically over the past several years, with consolidative immunotherapy after concurrent chemoradiation becoming the new standard of care. Five-year survival outcomes have substantially improved with this approach. Despite these advances, further improvements are needed as the majority of patients ultimately develop progression of disease. The next-generation immunotherapy trials are currently being conducted that include approaches such as concurrent immunotherapy and addition of other therapeutic agents in the concurrent and consolidative settings. Specific unmet needs continue to exist for patients who develop disease progression after concurrent chemoradiation and immunotherapy, as well as defining the best treatment for patients with driver mutations. Future directions also include refinement of radiation techniques to reduce toxicities as much as possible, as well as the use of circulating tumor DNA in the surveillance setting. The current scientific landscape shows promising approaches that may further improve outcomes for patients with locally advanced non-small-cell lung cancer.

Comparison of Hypermetabolic and Hypoxic Volumes Delineated on [18F]FDG and [18F]Fluoromisonidazole PET/CT in Non-small-cell Lung Cancer Patients

PURPOSE

The high rates of failure in the radiotherapy target volume suggest that patients with stage II or III non-small-cell lung cancer (NSCLC) should receive an increased total dose of radiotherapy. 2-Deoxy-2-[¹⁸F]fluoro-D-glucose ([¹⁸F]FDG) and [¹⁸F]fluoromisonidazole ([¹⁸F]FMISO) (hypoxia) uptake on pre-radiotherapy positron emission tomography (PET)/X-ray computed tomography (CT) have been independently reported to identify intratumor subvolumes at higher risk of relapse after radiotherapy. We have compared the [¹⁸F]FDG and [¹⁸F]FMISO volumes defined by PET/CT in NSCLC patients included in a prospective study.

PROCEDURES

Thirty-four patients with non-resectable lung cancer underwent [¹⁸F]FDG and [¹⁸F]FMISO PET/CT before (pre-RT) and during radiotherapy (around 42 Gy, per-RT). The criteria were to delineate 40 % and 90 % SUVmax thresholds on [¹⁸F]FDG PET/CT (metabolic volumes), and SUV > 1.4 on pre-RT [¹⁸F]FMISO PET/CT (hypoxic volume). The functional volumes were delineated within the tumor volume as defined on co-registered CTs.

RESULTS

The mean pre-RT and per-RT [¹⁸F]FDG volumes were not statistically different (30.4 cc vs 22.2; P = 0.12). The mean pre-RT SUVmax [¹⁸F]FDG was higher than per-RT SUVmax (12.7 vs 6.5; P < 0.0001). The mean [¹⁸F]FMISO SUVmax and volumes were 2.7 and 1.37 cc, respectively. Volume-based analysis showed good overlap between [¹⁸F]FDG and [¹⁸F]FMISO for all methods of segmentation but a poor correlation for Jaccard or Dice Indices (DI). The DI maximum was 0.45 for a threshold at 40 or 50 %.

CONCLUSION

The correlation between [¹⁸F]FDG and [¹⁸F]FMISO uptake is low in NSCLC, making it possible to envisage different management strategies as the studies in progress show.

Rationale for concurrent chemoradiotherapy for patients with stage III non-small-cell lung cancer

When treating patients with unresectable stage III non-small-cell lung cancer (NSCLC), those with a good performance status and disease measured within a radical treatment volume should be considered for definitive concurrent chemoradiotherapy (cCRT). This guidance is based on key scientific rationale from two large Phase 3 randomised studies and meta-analyses demonstrating the superiority of cCRT over sequential (sCRT). However, the efficacy of cCRT comes at the cost of increased acute toxicity versus sequential treatment. Currently, there are several documented approaches that are addressing this drawback, which this paper outlines. At the point of diagnosis, a multidisciplinary team (MDT) approach can enable accurate assessment of patients, to determine the optimal treatment strategy to minimise risks. In addition, reviewing the Advisory Committee on Radiation Oncology Practice (ACROP) guidelines can provide clinical oncologists with additional recommendations for outlining target volume and organ-at-risk delineation for standard clinical scenarios in definitive cCRT (and adjuvant radiotherapy). Furthermore, modern advances in radiotherapy treatment planning software and treatment delivery mean that radiation oncologists can safely treat substantially larger lung tumours with higher radiotherapy doses, with greater accuracy, whilst minimising the radiotherapy dose to the surrounding healthy tissues. The combination of these advances in cCRT may assist in creating comprehensive strategies to allow patients to receive potentially curative benefits from treatments such as immunotherapy, as well as minimising treatment-related risks.

Isotoxic Intensity Modulated Radiation Therapy in Stage III Non-Small Cell Lung Cancer: A Feasibility Study

PURPOSE

Not all patients with stage III non-small cell lung cancer (NSCLC) are suitable for concurrent chemoradiation therapy (CRT). Local failure rate is high for sequential concurrent CRT. As such, there is a rationale for treatment intensification.

METHODS AND MATERIALS

Isotoxic intensity modulated radiation therapy (IMRT) is a multicenter feasibility study that combines different intensification strategies including hyperfractionation, acceleration, and dose escalation facilitated by IMRT. Patients with unresectable stage III NSCLC, Eastern Cooperative Oncology Group (ECOG) performance status (PS) of 0 to 2, and unsuitable for concurrent CRT were recruited. A minimum of 2 cycles of platinum-based chemotherapy was compulsory before starting radiation therapy (RT). Radiation dose was increased until a maximum dose of 79.2 Gy was reached or 1 or more of the organs at risk met predefined constraints. RT was delivered in 1.8-Gy fractions twice daily, and an RT quality assurance program was implemented. The primary objective was the delivery of isotoxic IMRT to a dose >60 Gy equivalent dose in 2-Gy fractions (EQD2 assuming an α/β ratio of 10 Gy for acute reacting tissues).

RESULTS

Thirty-seven patients were recruited from 7 UK centers. Median age was 69.9 years (range, 46-86 years). The male-to-female ratio was 17:18. ECOG PS was 0 to 5 in 14.2% of patients; PS was 1 to 27 in 77.1% of patients; PS was 2 to 3 in 8.6% of patients. Stage IIIA:IIIB ratio was 22:13 (62.9%:37.1%). Of 37 patients, 2 (5.4%) failed to achieve EQD2 > 60 Gy. Median prescribed tumor dose was 77.4 Gy (range, 61.2-79.2 Gy). A maximum dose of 79.2Gy was achieved in 14 patients (37.8%). Grade 3 esophagitis was reported in 2 patients, and no patients developed grade 3 to 4 pneumonitis. There were 3 grade 5 events: acute radiation pneumonitis, bronchopulmonary hemorrhage, and acute lung infection. Median follow-up at time of analysis was 25.4 months (range, 8.0-44.2) months for 11 of 35 survivors. The median survival was 18.1 months (95% confidence interval [CI], 13.9-30.6), 2-year overall survival was 33.6% (95% CI, 17.9-50.1), and progression-free survival was 23.9% (95% CI, 11.3-39.1).

CONCLUSIONS

Isotoxic IMRT is a well-tolerated and feasible approach to treatment intensification.

Study protocol: a multicentre, prospective, phase II trial of isotoxic hypofractionated concurrent chemoradiotherapy for non-small cell lung cancer

INTRODUCTION

Concurrent chemoradiotherapy with conventional fractionation has been acknowledged as one of the standard treatments for locally advanced non-small cell lung cancer (NSCLC). The radiotherapy dose of 60 Gy is far from enough for local tumour control. Due to this fact, hypofractionated radiotherapy can shorten the total treatment duration, partially counteract the accelerated repopulation of tumour cells and deliver a higher biological effective dose, it has been increasingly used for NSCLC. In theory, concurrent hypofractionated chemoradiotherapy can result in an enhanced curative effect. To date, the vast majority of radiotherapy prescriptions assign a uniform radiotherapy dose to all patients. However this kind of uniform radiotherapy prescription may lead to two consequences: excess damage to normal tissues for large tumours and insufficient dose for small tumours. Our study aims to evaluate whether delivering individualised radiotherapy dose is feasible using intensity-modulated radiotherapy.

METHODS AND ANALYSIS

Our study of individualised radiotherapy is a multicenter phase II trial. From April 2019, a total of 30 patients from three Chinese centres, with a proven histological or cytological diagnosis of inoperable NSCLC, will be recruited. The dose of radiation will be increased until one or more of the organs at risk tolerance or the maximum dose of 69 Gy is reached. The primary end point is feasibility, with response rates, progression-free survival and overall survival as secondary end points. The concurrent chemotherapy regimen will be docetaxel plus lobaplatin.

ETHICS AND DISSEMINATION

The study has been approved by medical ethics committees from three research centres. The trial is conducted in accordance with the Declaration of Helsinki.The trial results will be disseminated through academic conference presentations and peer-reviewed publications.

TRIAL REGISTRATION NUMBER

NCT03606239.

Radiotherapy Dose and Induction Chemotherapy Cycles Are Associated With Prognosis and Toxicity Risk: A Retrospective Study of 227 Patients With Unresectable Stage III Non-Small-Cell Lung Cancer

Objective:

Concurrent chemoradiation (cCHRT) has been confirmed as the standard treatment for local advanced non-small-cell lung cancer (NSCLC). This study is to assess the appropriate timing of radiotherapy and cycles of induction chemotherapy for those patients.

Methods:

227 inoperable stage III NSCLC patients were selected, we analyzed the potential prognostic factors and the influence of induction chemotherapy was evaluated.

Results:

The median survival time was 20.7 months; only 25 patients chose chemotherapy alone (11.0%), 137 patients underwent sequential chemoradiation (sCHRT, 60.4%), and 65 patients received cCHRT (28.6%). Multivariate analyses showed radiation therapy (P = 0.001), the Eastern Cooperative Oncology Group (ECOG) score (P = 0.000) and the lymph node stage (P = 0.001) were independent prognostic factors. cCHRT was not found to be superior (P = 0.330). We selected patients received 60-66 Gy and found the cCHRT groups achieved a relatively better outcome, with a median Overall Survival (OS) of 25.2 months vs 20.1 months in the sCHRT group (P = 0.019). We also found cycles of induction chemotherapy did not compromise survival; however, ≥3 cycles resulted in more grade 3-4 hematology toxicities, with a proportion of 18/99 compared with 53/103 among patients who underwent ≤3 cycles. In addition, higher grade hematology toxicities and poor ECOG were also the most common reasons for abandoning cCHRT.

Conclusions:

For inoperable stage III NSCLC, cCHRT showed its superiority only when the radiotherapy dose was 60-66 Gy. Cycles of induction chemotherapy did not interfere with survival; however, ≥3 cycles resulted in more grade 3-4 hematology toxicities, leading to the cessation of cCHRT.

Efficacy of chemoradiotherapy versus radiation alone in patients with inoperable locally advanced non-small-cell lung cancer: A meta-analysis and systematic review

BACKGROUND

This meta-analysis compared radiotherapy (RT) versus concurrent chemoradiotherapy (RT+CT) in treating patients with inoperable stage III non-small-cell lung cancer (NSCLC).

METHODS

Medline, Cochrane, EMBASE, Google Scholar databases were searched until July 28, 2015 using the following keywords non-small cell lung cancer, advanced cancer, incurable/inoperable/unresectable, chemotherapy, radiotherapy, chemoradiotherapy/chemoradiation. Randomized controlled trials (RCTs) and two-armed prospective studies that compared combined RT+CT with RT alone in patients with locally advanced (stage III) nonresectable NSCLC were eligible for inclusion. Treatment effect on overall survival, progression-free survival (PFS), and objective response rate (ORR) were evaluated.

RESULTS

Ultimately, 13 RCT studies were included in the systematic review and meta-analysis. The 13 studies included a total of 1936 patients with incurable/inoperable stage III NSCLC, of which 975 received RT alone and 961 received RT+CT combination therapy. The average age ranged from 54 to 77 years. At 1 and 2 years after treatment, the pooled data reveal that patients receiving CT+RT combination therapy had higher overall survival (pooled hazard ratio (HR), 0.72; 95% CI, 0.62-0.84; P < .001; 1-yr: HR, 0.67; 95% CI, 0.54-0.84; P < .001; 2-year: HR, 0.57; 95% CI, 0.45-0.73; P < .001), higher PFS (pooled HR, 0.73, 95% CI, 0.60-0.89; P = .002; 1-year: HR, 0.36; 95% CI, 0.24-0.53; P < .001; 2-year: HR, 0.38; 95% CI, 0.23-0.63; P < .001).

CONCLUSION

Our findings show higher efficacy for concurrent CT+RT over RT alone in treating locally-advanced, unresectable stage III NSCLC.

The multifaceted roles of FOXM1 in pulmonary disease

Forkhead box M1 (FOXM1), a transcriptional regulator of G1/S and G2/M transition and M phase progression in the cell cycle, plays a principal role in many physiological and pathological processes. A growing number of studies have focused on the relationship between abnormal FOXM1 expression and pulmonary diseases, such as lung cancer, chronic obstructive pulmonary disease (COPD), asthma, acute lung injury (ALI), pulmonary fibrosis, and pulmonary arterial hypertension (PAH). These studies indicate that the FOXM1 regulatory network is a major predictor of poor outcomes, especially in lung cancer, and provide novel insight into various pulmonary diseases. For the first time, this review summarizes the mechanistic relationship between FOXM1 dysregulation and pulmonary diseases, the benefits of targeting abnormal FOXM1 expression, and the questions that remain to be addressed in the future.

Effects of combined inhibition of STAT3 and VEGFR2 pathways on the radiosensitivity of non-small-cell lung cancer cells

Purpose

The goals of this study were to determine the effects of combined inhibition of STAT3 and vascular endothelial growth factor receptor 2 (VEGFR2) pathways on the radiosensitivity of non-small-cell lung cancer (NSCLC) cells, and to assess the underlying mechanisms.

Methods

The expressions of VEGFR2, STAT3, related signaling molecules, hypoxia-inducible factor 1-alpha (HIF-1α), and cyclin D1 were determined by Western blotting. Radiosensitivity was assessed using the colony-forming assay, and cell cycle and cell death were analyzed by flow cytometry. A nude mouse xenograft tumor model of Calu-1 cells was established. The hepatorenal toxicity of the above-mentioned treatment on tumor-bearing mice was observed by H&E staining. The expression of STAT3, VEGFR2, HIF-1α, and cyclin D1 of the transplanted tumor tissues was detected by immunohistochemistry. Apoptosis of tumor tissues was evaluated by TUNEL staining.

Results

In vitro, we selected two cell lines with high expression levels of STAT3, including Calu-1 cells that exhibit high VEGFR2 expression and A549 cells that exhibit low VEGFR2 expression. When apatinib treatment was combined with S3I-201, the expression of VEGFR2, STAT3, and their downstream signaling molecules was significantly decreased (P<0.01). There was an increase in cell death and G2/M phase arrest after treatments, with the most significant changes occurring upon dual inhibition of STAT3 and VEGFR2 (P<0.01). In vivo, combined treatment of radiotherapy and dual inhibition of VEGFR2 and STAT3 was well tolerated and did not deliver additional toxicity. Compared with the control group and the radiation treatment (RT) + apatinib or RT + S3I-201 duplex group, the expression level of STAT3, p-STAT3, VEGFR2, HIF-1α, and cyclin D1 in the triple group (RT + apatinib + S3I-201) was the lowest, and the proportion of apoptotic cells was the highest (P<0.05).

Conclusion

The combined inhibition of VEGFR2 and STAT3 is effective in enhancing radiosensitizing effects in NSCLC cells.

Radical radiotherapy or chemoradiotherapy for inoperable, locally advanced, non-small cell lung cancer: Analysis of patient profile, treatment approaches, and outcomes for 213 patients at a tertiary cancer center

INTRODUCTION

Radical radiotherapy (RT) with curative intent, with or without chemotherapy, is the standard treatment for inoperable, locally advanced nonsmall cell lung cancer (NSCLC).

MATERIALS AND METHODS

We retrospectively reviewed the data for all 288 patients who presented with inoperable, locally advanced NSCLC at our institution, between May 2011 and December 2016.

RESULTS

RT alone or sequential chemoradiotherapy (SCRT) or concurrent chemoradiotherapy (CCRT) was used for 213 patients. Median age was 64 years (range: 27-88 years). Stage-III was the biggest stage group with 189 (88.7%) patients. Most patients with performance status (PS) 0 or 1 received CCRT, whereas most patients with PS 2 received RT alone (P < 0.001). CCRT, SCRT, and RT alone were used for 120 (56.3%), 24 (11.3%), and 69 (32.4%) patients, respectively. A third of all patients (32.4%) required either volumetric-modulated arc radiotherapy (VMAT) or tomotherapy. Median follow-up was 16 months. The median progression-free survival and median overall survival (OS) were 11 and 20 months, respectively. One-year OS and 2-year OS were 67.9% and 40.7%, respectively. Patients treated using CCRT lived significantly longer with a median survival of 28 months, compared with 13 months using SCRT and RT alone (P < 0.001). On multivariate analysis, OS was significantly affected by age, stage group, treatment approach, and response to treatment.

CONCLUSION

RT including CCRT is feasible, safe, and well tolerated in our patient population and results in survival benefits comparable with published literature. CCRT should be considered for all patients with inoperable, locally advanced NSCLC, who are fit and have good PS.

Comparative effectiveness of concurrent chemoradiotherapy versus EGFR-tyrosine kinase inhibitors for the treatment of clinical stage IIIb lung adenocarcinoma patients with mutant EGFR

BACKGROUND

The standard of care for fit locally advanced non-small cell lung cancer (NSCLC) patients is concurrent chemoradiotherapy (CCRT). However, in a subset of patients with lung adenocarcinoma with mutant EGFR (LA-mEGFR), the role of EGFR-tyrosine kinase inhibitors (TKIs) is not clear. We compared CCRT versus TKIs for the treatment of stage IIIb LA-mEGFR in a Taiwanese population.

METHODS

We identified patients from the Taiwan Cancer Registry with good performance status at clinical stage IIIb LA-mEGFR, diagnosed from June 2011 to December 2015 and treated with either TKIs or CCRT. Clinical covariables and survival status were also collected. The Cox regression method was used in the primary analyses and several propensity score methods and alternative study cohort definitions were used in additional analyses.

RESULTS

We compared the data of 177 TKI and 22 CCRT patients and found no statistically significant difference in overall (adjusted hazard ratio of death 0.71, 95% confidence interval 0.34-1.47) or lung cancer-specific survival (hazard ratio 0.65, 95% confidence interval 0.31-1.35). The results of most additional analyses were insignificant.

CONCLUSION

In this population-based study from Taiwan with limited case numbers, no statistical difference in the survival outcomes of patients with clinical stage IIIb LA-mEGFR treated with either EGFR-TKIs or CCRT was determined. Further prospective studies are needed to clarify our findings.

Actual gains in dosimetry and treatment delivery efficiency from volumetric modulated arc radiotherapy for inoperable, locally advanced lung cancer over five-field forward-planned intensity-modulated radiotherapy

AIMS

Volumetric modulated arc radiotherapy (VMAT) is used for inoperable, locally advanced nonsmall cell lung cancer, where three-dimensional conformal radiotherapy (3D-CRT) cannot yield an acceptable plan.

METHODS

The planning and treatment data were prospectively collected on the first 18 patients treated using VMAT plans. We analyzed the actual dosimetric gain and impact on treatment, compared with complex multisegment 3D-CRT (five-field forward-planned intensity-modulated radiotherapy [IMRT]) that were generated for treatment. Proportion of planning target volume (PTV) receiving 95% dose (PTV-V95%) conformity index (CI), conformity number (CN), dose homogeneity index (DHI), monitor units (MUs), and treatment time were also analyzed.

RESULTS

The PTV coverage (PTV-V95%) was improved from a median of 91.41% for 5-F forward-IMRT to 98.25% for VMAT (P < 0.001). The CI improved with a mean of 1.12 for VMAT and 1.31 for 5-F forward-IMRT (P < 0.001). The mean DHI improved from 1.15 for forward-IMRT to 1.08 for VMAT (P < 0.001). The mean CN improved from 0.62 for forward-IMRT to 0.87 for VMAT (P < 0.001). No significant increase in the low-dose bath (V5, V10 and mean lung dose) to the lung was seen. Significantly higher number of MUs (P < 0.001) and shorter treatment delivery times (P = 0.03) were seen with VMAT.

CONCLUSION

VMAT resulted in improvement in target volume coverage, demonstrated by PTV-V95%, CI, CN, and DHI, without any increase in the low-dose bath to the lung. For conventional fractionation, VMAT requires more MUs (P < 0.001) but has a shorter treatment delivery time (P = 0.03) per fraction.

Is heterogeneity in stage 3 non-small cell lung cancer obscuring the potential benefits of dose-escalated concurrent chemo-radiotherapy in clinical trials?

The current standard of care for the management of inoperable stage 3 non-small cell lung cancer (NSCLC) is concurrent chemoradiotherapy (cCRT) using radiotherapy dose-fractionation and chemotherapy regimens that were established 3 decades ago. In an attempt to improve the chances of long-term control from cCRT, dose-escalation of the radiotherapy dose was assessed in the RTOG 0617 randomised control study comparing the standard 60 Gy in 30 fractions with a high-dose arm receiving 74 Gy in 37 fractions. Following the publication of this trial the thoracic oncology community were surprised to learn that there was worse survival in the dose-escalated arm and that for now the standard of care must remain with the lower dose. In this article we review the RTOG 0617 paper with subsequent analyses and studies to explore why the use of dose-escalated cCRT in stage 3 NSCLC has not shown the benefits that were expected. The overarching theme of this opinion piece is how heterogeneity between stage 3 NSCLC cases in terms of patient, tumour, and clinical factors may obscure the potential benefits of dose-escalation by causing imbalances in the arms of studies such as RTOG 0617. We also examine recent advances in the staging, management, and technological delivery of radiotherapy in NSCLC and how these may be employed to optimise cCRT trials in the future and ensure that any potential benefits of dose-escalation can be detected.

Prognostic value of primary tumor SUVmax on pre-treatment 18F-FDG PET/CT imaging in patients with stage iii non-small cell lung cancer

OBJECTIVES

Concomitant chemoradiotherapy (CCRT) is widely used in the treatment of patients with stage iii non-small cell lung carcinoma (NSCLC). The early identification of patients with poor prognosis is the premise of personalized treatment for patients. The aim of the study was to evaluate the prognostic value of clinical parameters and primary tumor SUVmax on pre-treatment 18F-FDG PET/CT in patients with stage iii NSCLC.

MATERIAL AND METHODS

Clinical records of 79 stage iii-NSCLC patients with pre-treatment 18F-FDG PET/CT imaging, treated with definitive CCRT were retrospectively reviewed. The clinical endpoints in terms of progression-free survival (PFS) and overall survival (OS) were correlated with the median pre-treatment primary tumor SUVmax. Furthermore, other factors influencing patient outcome were analyzed.

RESULTS

The median age of patients was 58 years (range, 45-71) with 72 (91%) males. Squamous cell carcinoma (73%) was the most common histologic type. Performance status was very good (ECOG 0) in 64.5% of patients. Sixty (79%) patients had died at the time of this analysis. Median OS and PFS were 22.5 and 12.0 months, respectively. Patients were dichotomized according to pre-treatment primary tumor SUVmax≤15.0 vs.>15.0. There was no statistically significant difference for OS and PFS in both arms. Multivariate analysis showed that pre-treatment SUVmax was not a significant predictor of OS (HR 1.099, P=0.726) and PFS (HR 1.022, P=0.941).

CONCLUSIONS

SUVmax with threshold value of 15.0 on the primary tumor before treatment had no prognostic value in our patient group with stage iii NSCLC treated with definitive CCRT.

Poly (ADP-ribose) polymerase inhibitor, an effective radiosensitizer in lung and pancreatic cancers

The development of stereotactic body radiation therapy (SBRT) has revolutionized radiation therapy for lung cancers and is an emerging treatment option for pancreatic cancers. However, there are many questions on how to optimize its use in chemoradiotherapy. The most relevant addition to radiotherapy regimens are inhibitors of DNA repair and DNA damage response pathways. One such class of agents are inhibitors of poly (ADP-ribose) polymerase (PARP). In this study we examined the effects of the PARP inhibitor LT626 in combination with ionizing radiation in lung and pancreatic cancers. Our study demonstrated that combination treatment with LT626 and radiation effectively inhibited growth in lung and pancreatic cancer cell lines, better than individual treatment alone. Combination treatment also increased expression of γH2AX and 53BP1 foci and upregulated expression of phosphorylated ATM, ATR and their respective kinases. Using in vivo lung cancer xenograft models we demonstrated that LT626 functioned as an effective radiosensitizer during fractionated radiation treatment, leading to significant decrease in tumor burden and doubling the median survival compared to control group. Overall our in vitro and in vivo studies showed that PARP inhibitor LT626 acted synergistically with radiation in lung and pancreatic cancers.

A population-based comparative effectiveness study of chemoradiation regimens and sequences in stage III non-small cell lung cancer

OBJECTIVES

In patients receiving concurrent chemoradiation for locally advanced non-small cell lung cancer (NSCLC), consolidation chemotherapy is frequently given even though several randomized trials have failed to show a benefit. We explored the potential benefits of consolidation chemotherapy using a population-based comparative effectiveness approach.

MATERIALS AND METHODS

Surveillance, Epidemiology, and End Results-Medicare was used to identify patients with Stage III NSCLC aged ≥65 and diagnosed 2002-2009. We selected patients who received concurrent chemoradiotherapy and determined whether they were (concurrent-consolidation) or were not (concurrent-alone) treated with consolidation chemotherapy. Outcomes were overall and cancer specific survival using a conditional landmark analysis approach.

RESULTS

1688 patients treated with concurrent-alone or concurrent-consolidation were identified with a median follow up of 29 months. Choice of chemotherapy agents did not correlate with outcome. For concurrent-consolidation versus concurrent-alone, the median overall survival was 21 months versus 18 months, respectively (log-rank p=0.008) and the median cancer specific survival was 23 months versus 19 months, respectively (log-rank p=0.03). On multivariate analysis, concurrent-consolidation remained associated with improved overall survival (HR 0.85, p=0.04), and there was a trend for improved cancer specific survival (HR 0.87, p=0.12). Inverse probability of treatment weighting using propensity scores demonstrated similar findings. Importantly, the benefit of concurrent-consolidation held only for patients treated with carboplatin-taxane but not with cisplatin-etoposide.

CONCLUSION

Survival outcomes were similar among the five most commonly employed platinum-based doublets. We found that patients receiving cisplatin during radiation do not appear to benefit from additional chemotherapy. However, for patients receiving carboplatin, consolidation chemotherapy was associated with improved overall and cancer specific survival.

Feasibility and efficacy of helical intensity-modulated radiotherapy for stage III non-small cell lung cancer in comparison with conventionally fractionated 3D-CRT

BACKGROUND

The standard treatment for stage III non-small-cell lung cancer (NSCLC) is still 60 Gy in conventional fractions combined with concurrent chemotherapy; however, the resulting local controls are disappointing. The aim of this study was to compare and assess the feasibility and efficacy of hypofractionated chemoradiotherapy using helical tomotherapy (HT) with conventional fractionation as opposed to using three-dimensional conformal radiotherapy (3D-CRT) for stage III NSCLC.

METHODS

Sixty-nine patients with stage III (AJCC 7th edition) NSCLC who underwent definitive radiation treatment at our institution between July 2011 and November 2013 were reviewed and analyzed retrospectively. A dose of 60 Gy in 20 fractions was delivered in the HT group (n=34), whereas 60 Gy in 30 fractions in the 3D-CRT group (n=35). Primary endpoints were toxicity, overall response rate, overall survival (OS) and progression-free survival (PFS).

RESULTS

The median follow-up period was 26.4 months. V20 (P=0.005), V30 (P=0.001), V40 (P=0.004), mean lung dose (P=0.000) and max dose of spinal cord (P=0.005) were significantly lower in the HT group than in the 3D-CRT group. There was no significant difference in the incidences of acute radiation pneumonitis (RP) ≥ grade 2 between the two groups, whereas the incidences of acute radiation esophagitis ≥ grade 2 were significantly lower in the HT group than in the 3D-CRT group (P=0.027). Two-year overall response rate was significantly higher in the HT group than in the 3D-CRT group (P=0.015). One- and 2-year OS rates were significantly higher in the HT group (95.0% and 68.7%, respectively) than in the 3D-CRT group (85.5% and 47.6%, respectively; P=0.0236). One- and 2-year PFS rates were significantly higher in the HT group (57.8% and 26.3%, respectively) than in the 3D-CRT group (32.7% and 11.4%, respectively; P=0.0351). Univariate analysis indicated that performance status (PS), T stage and radiotherapy technique were significant prognostic factors for both OS and PFS. Multivariate analysis indicated that PS and radiotherapy technique were independent prognostic factors of OS and PS was independent prognostic factor of PFS.

CONCLUSIONS

Hypofractionated chemoradiotherapy via HT can shorten the radiotherapy time without increasing treatment-related toxicity. The preliminary findings are that OS and PFS can be improved by hypofractionated chemoradiotherapy via HT for patients with stage III NSCLC.

miR-17-92/p38α Dysregulation Enhances Wnt Signaling and Selects Lgr6+ Cancer Stem-like Cells during Lung Adenocarcinoma Progression

Defining the molecular and cellular roots of lung cancer relapse after initial treatment remains an imperative to improve survival. Here we report that the lung stem cell marker Lgr6 becomes enriched in non-small cell lung cancer (NSCLC) cells during malignant progression. Lgr6(+) NSCLC cells displayed self-renewal and differentiation properties along with a higher tumorigenic potential. Mechanistic investigations suggested that a defective repression of the miR-17-92 gene cluster was responsible for evolution of a selection for outgrowth of Lgr6(+) NSCLC cells. High levels of expression of miR-19 family members were found to target and downregulate levels of p38α kinase, providing a specific survival signal for Lgr6(+) cells as mediated by increased Wnt/ß-catenin activity. Our results identify a specific stem-like cell population in NSCLC with increased malignant potential, the elucidation of which may enable earlier prognosis and possibly the development of more effective targeted treatments. Cancer Res; 76(13); 4012-22. ©2016 AACR.

Accelerated hypofractionated three-dimensional conformal radiation therapy (3 Gy/fraction) combined with concurrent chemotherapy for patients with unresectable stage III non-small cell lung cancer: preliminary results of an early terminated phase II trial

BACKGROUND

Increasing the biological effective dose (BED) of radiotherapy for non-small cell lung cancer (NSCLC) can increase local control rates and improve overall survival. Compared with conventional fractionated radiotherapy, accelerated hypofractionated radiotherapy can yield higher BED, shorten the total treatment time, and theoretically obtain better efficacy. However, currently, there is no optimal hypofractionated radiotherapy regimen. Based on phase I trial results, we performed this phase II trial to further evaluate the safety and preliminary efficacy of accelerated hypofractionated three-dimensional conformal radiation therapy(3-DCRT) combined with concurrent chemotherapy for patients with unresectable stage III NSCLC.

METHODS

Patients with previously untreated unresectable stage III NSCLC received 3-DCRT with a total dose of 69 Gy, delivered at 3 Gy per fraction, once daily, five fractions per week, completed within 4.6 weeks. At the same time, platinum doublet chemotherapy was applied.

RESULTS

After 12 patients were enrolled in the group, the trial was terminated early. There were five cases of grade III radiation esophagitis, of which four cases completed the radiation doses of 51 Gy, 51 Gy, 54 Gy, and 66 Gy, and one case had 16 days of radiation interruption. The incidence of grade III acute esophagitis in patients receiving an irradiation dose per fraction ≥2.7 Gy on the esophagus was 83.3% (5/6). The incidence of symptomatic grade III radiation pneumonitis among the seven patients who completed 69 Gy according to the plan was 28.6% (2/7). The median local control (LC) and overall survival (OS) were not achieved; the 1-year LC rate was 59.3%, and the 1-year OS rate was 78.6%.

CONCLUSION

For unresectable stage III NSCLC, the accelerated hypofractionated radiotherapy with a total dose of 69 Gy (3 Gy/f) combined with concurrent chemotherapy might result in severe radiation esophagitis and pneumonitis to severely affect the completion of the radiotherapy. Therefore, we considered that this regimen was infeasible. During the hypofractionated radiotherapy with concurrent chemotherapy, the irradiation dose per fraction to esophagus should be lower than 2.7 Gy. Further studies should be performed using esophageal tolerance as a metric in dose escalation protocols.

TRIAL REGISTRATION

NCT02720614, the date of registration: March 23, 2016.

Patients Selected for Definitive Concurrent Chemoradiation at High-volume Facilities Achieve Improved Survival in Stage III Non-Small-Cell Lung Cancer

BACKGROUND

The relationship between provider experience and clinical outcomes is poorly defined in radiation oncology. This study examined the impact of facility case volume on overall survival in patients with stage III non-small cell lung cancer (NSCLC) treated with definitive concurrent chemoradiation therapy (CCRT).

METHODS

Using the National Cancer Data Base, we identified clinical stage III NSCLC patients diagnosed in 2004 to 2006 who were treated with definitive CCRT to 59.4-74.0 Gy. High-volume facilities (HVF) were defined as those in the ninetieth percentile of annual CCRT volume (≥12 cases/year). Independent predictors of receiving CCRT at HVF were identified using multivariable logistic regression. Overall survival based on receiving CCRT at HVF was assessed using Kaplan-Meier analysis, Cox proportional hazards regression, and propensity score matching.

RESULTS

Among 10,072 included patients, 1207 (12.0%) were treated at HVF. Patients in HVF were more likely to have a higher Charlson-Deyo comorbidity score, more advanced nodal stage, higher doses, and 3D-conformal or intensity-modulated radiotherapy. When controlling for demographic and clinical covariates including academic affiliation, treatment at HVF was independently associated with a significantly decreased risk of death (hazards ratio = 0.93; 95% confidence interval: 0.87-0.99; p = 0.03). Propensity score matching showed that these findings were robust (hazards ratio = 0.91; 95% confidence interval: 0.84-0.99; p = 0.04).

CONCLUSIONS

Our findings suggest that treatment at HVF is associated with improved overall survival among stage III NSCLC patients receiving definitive CCRT, independent of academic affiliation. Further research is needed to determine whether or not efforts supporting centralization of radiotherapy at HVF will improve population-based survival, toxicities, and costs.

Improved progression free survival for patients with diabetes and locally advanced non-small cell lung cancer (NSCLC) using metformin during concurrent chemoradiotherapy

BACKGROUND AND PURPOSE

The aim was to investigate whether the use of metformin during concurrent chemoradiotherapy (cCRT) for locally advanced non-small cell lung cancer (NSCLC) improved treatment outcome.

MATERIAL AND METHODS

A total of 682 patients were included in this retrospective cohort study (59 metformin users, 623 control patients). All received cCRT in one of three participating radiation oncology departments in the Netherlands between January 2008 and January 2013. Primary endpoint was locoregional recurrence free survival (LRFS), secondary endpoints were overall survival (OS), progression-free survival (PFS) and distant metastasis free survival (DMFS).

RESULTS

No significant differences in LRFS or OS were found. Metformin use was associated with an improved DMFS (74% versus 53% at 2 years; p=0.01) and PFS (58% versus 37% at 2 years and a median PFS of 41 months versus 15 months; p=0.01). In a multivariate cox-regression analysis, the use of metformin was a statistically significant independent variable for DMFS and PFS (p=0.02 and 0.03).

CONCLUSIONS

Metformin use during cCRT is associated with an improved DMFS and PFS for locally advanced NSCLC patients, suggesting that metformin may be a valuable treatment addition in these patients. Evidently, our results merit to be verified in a prospective trial.

A novel cytostatic form of autophagy in sensitization of non-small cell lung cancer cells to radiation by vitamin D and the vitamin D analog, EB 1089

The standard of care for unresectable lung cancer is chemoradiation. However, therapeutic options are limited and patients are rarely cured. We have previously shown that vitamin D and vitamin D analogs such as EB 1089 can enhance the response to radiation in breast cancer through the promotion of a cytotoxic form of autophagy. In A549 and H460 non-small cell lung cancer (NSCLC) cells, 1,25-D3 (the hormonally active form of vitamin D) and EB 1089 prolonged the growth arrest induced by radiation alone and suppressed proliferative recovery, which translated to a significant reduction in clonogenic survival. In H838 or H358 NSCLC cells, which lack VDR/vitamin D receptor or functional TP53, respectively, 1,25-D3 failed to modify the extent of radiation-induced growth arrest or suppress proliferative recovery post-irradiation. Sensitization to radiation in H1299 NSCLC cells was evident only when TP53 was induced in otherwise tp53-null H1299 NSCLC cells. Sensitization was not associated with increased DNA damage, decreased DNA repair or an increase in apoptosis, necrosis, or senescence. Instead sensitization appeared to be a consequence of the conversion of the cytoprotective autophagy induced by radiation alone to a novel cytostatic form of autophagy by the combination of 1,25-D3 or EB 1089 with radiation. While both pharmacological and genetic suppression of autophagy or inhibition of AMPK phosphorylation sensitized the NSCLC cells to radiation alone, inhibition of the cytostatic autophagy induced by the combination treatment reversed sensitization. Evidence for selectivity was provided by lack of radiosensitization in normal human bronchial cells and cardiomyocytes. Taken together, these studies have identified a unique cytostatic function of autophagy that appears to be mediated by VDR, TP53, and possibly AMPK in the promotion of an enhanced response to radiation by 1,25-D3 and EB 1089 in NSCLC.

Definitive radiotherapy with concurrent oncothermia for stage IIIB non-small-cell lung cancer: A case report

Hyperthermia enhances the susceptibility of tumors to radiotherapy (RT) and chemotherapy. Oncothermia, also known as electro-hyperthermia, is a new treatment modality developed to overcome the problems of traditional hyperthermia by selectively delivering energy to the malignant tissues. The present study reports the outcome of combined oncothermia and RT in a 75-year-old patient with stage IIIB non-small-cell lung cancer (NSCLC). Due to the advanced age and the performance status of the patient, the combination of systemic chemotherapy and RT was deemed infeasible; therefore, the patient instead decided to undergo oncothermia concurrently with definitive RT. The RT was administered at a dose of 64.8 Gy in 36 fractions using a three-dimensional conformal plan technique. Oncothermia was started concomitantly with RT and was performed for 60 min per session, two sessions per week, for a total of 12 sessions. No severe toxicities developed, with the exception of mild odynophagia, which resolved soon after the treatments. Follow-up computed tomography showed complete tumor response, and the patient was alive with no evidence of the disease 18 months after the completion of the treatment. In conclusion, the present case report suggests that oncothermia combined with RT, with the former possessing radiosensitizing potential and no additional toxicities, may be a promising alternative for advanced-age and/or frail patients with locally advanced NSCLC.

Genome-wide siRNA Screen Identifies the Radiosensitizing Effect of Downregulation of MASTL and FOXM1 in NSCLC

Lung cancer is the most common cancer worldwide and on top of that has a very poor prognosis, which is reflected by a 5-year survival rate of 5% to 15%. Radiotherapy is an integral part of most treatment regimens for this type of tumor, often combined with radiosensitizing cytotoxic drugs. In this study, we identified many genes that could potentially be exploited for targeted radiosensitization using a genome-wide siRNA screen in non-small cell lung cancer (NSCLC) cells. The screen identified 433 siRNAs that potentially sensitize lung cancer cells to radiation. Validation experiments showed that knockdown of expression of Forkhead box M1 (FOXM1) or microtubule-associated serine/threonine kinase-like (MASTL) indeed causes radiosensitization in a panel of NSCLC cells. Strikingly, this effect was not observed in primary human fibroblasts, suggesting that the observed radiosensitization is specific for cancer cells. Phosphoproteomics analyses with and without irradiation showed that a number of cell-cycle-related proteins were significantly less phosphorylated after MASTL knockdown in comparison to the control, while there were no changes in the levels of phosphorylation of DNA damage response proteins. Subsequent analyses showed that MASTL knockdown cells respond differently to radiation, with a significantly shortened G2-M phase arrest and defects in cytokinesis, which are followed by a cell-cycle arrest. In summary, we have identified many potential therapeutic targets that could be used for radiosensitization of NSCLC cells, with MASTL being a very promising and druggable target to combine with radiotherapy.

Areas of high 18F-FDG uptake on preradiotherapy PET/CT identify preferential sites of local relapse after chemoradiotherapy for non-small cell lung cancer

The high rates of failure in the radiotherapy target volume suggest that patients with stage II or III non-small cell lung cancer (NSCLC) should receive an increased total dose of radiotherapy. Areas of high (18)F-FDG uptake on preradiotherapy (18)F-FDG PET/CT have been reported to identify intratumor subvolumes at high risk of relapse after radiotherapy. We wanted to confirm these observations on a cohort of patients included in 3 sequential prospective studies. Our aim was to assess an appropriate threshold (percentage of maximum standardized uptake value [SUVmax]) to delineate subvolumes on staging (18)F-FDG PET/CT scans assuming that a smaller target volume would facilitate isotoxic radiotherapy dose escalation.

METHODS

Thirty-nine patients with inoperable stage II or III NSCLC, treated with chemoradiation or with radiotherapy alone, were extracted from 3 prospective studies (ClinicalTrials.gov identifiers NCT01261585, NCT01261598, and RECF0645). All patients underwent (18)F-FDG PET/CT at initial staging, before radiotherapy, during radiotherapy, and during systematic follow-up in a single institution. All (18)F-FDG PET/CT acquisitions were coregistered on the initial scan. Various subvolumes in the initial acquisition (30%, 40%, 50%, 60%, 70%, 80%, and 90% SUVmax thresholds) and in the 3 subsequent acquisitions (40% and 90% SUVmax thresholds) were pasted on the initial scan and compared.

RESULTS

Seventeen patients had a local relapse. The SUVmax measured during radiotherapy was significantly higher in locally relapsed tumors than in locally controlled tumors (mean, 6.8 vs. 4.6; P = 0.02). The subvolumes delineated on initial PET/CT scans with 70%-90% SUVmax thresholds were in good agreement with the recurrent volume at a 40% SUVmax threshold (common volume/baseline volume, 0.60-0.80). The subvolumes delineated on initial PET/CT scans with 30%-60% SUVmax thresholds were in good to excellent agreement with the core volume of the relapse (90% SUVmax threshold) (common volume/recurrent volume and overlap fraction indices, 0.60-0.93). The agreement was moderate (>0.51) when a 70% SUVmax threshold was used to delineate on initial PET/CT scans.

CONCLUSION

High (18)F-FDG uptake areas on pretreatment PET/CT scans identify tumor subvolumes at greater risk of relapse in patients with NSCLC treated by concomitant chemoradiation. We propose a 70% SUVmax threshold to delineate areas of high (18)F-FDG uptake on initial PET/CT scans as the target volumes for potential radiotherapy dose escalation.

How Do Elderly Poor Prognosis Patients Tolerate Palliative Concurrent Chemoradiotherapy for Locally Advanced Non-Small-Cell Lung Cancer Stage III? A Subset Analysis From a Clinical Phase III Trial

BACKGROUND

In a phase III trial of patients with unresectable, locally advanced, stage III non-small-cell lung cancer (NSCLC) with a poor prognosis, palliative concurrent chemoradiotherapy (CRT) provided a significantly better outcome than chemotherapy alone, except among performance status (PS) 2 patients. In the present subgroup analysis, we evaluated the effect on patients aged ≥ 70 years (42% of all included) compared with patients aged < 70 years enrolled in the trial.

PATIENTS AND METHODS

All patients received 4 courses of intravenous carboplatin and oral vinorelbine. The experimental arm also received radiotherapy (42 Gy in 15 fractions). The included patients were required to have large tumors (> 8 cm), weight loss (> 10% within the previous 6 months) and/or PS 2.

RESULTS

The overall survival was increased among the CRT patients in both age groups, but the difference was significant only in patients aged < 70 years (median survival, 14.8 vs. 9.7 months; P = .001; age ≥ 70 years, median survival, 10.2 vs. 9.1 months; P = .09). Patients aged ≥ 70 years experienced better preserved health-related quality of life (QOL) and significantly less hematologic toxicity. The 2- and 3-year survival was significantly increased in both age groups receiving CRT.

CONCLUSION

Elderly patients aged ≥ 70 years with unresectable, stage III, locally advanced, NSLCL and a poor prognosis can tolerate CRT with the doses adjusted to age and palliative intent. These results indicate that CRT can provide both survival and QOL benefits in elderly patients, except for those with PS 2 or worse. The male predominance in the ≥ 70-year-age group and the reduced chemotherapy intensity for the patients aged > 75 years might explain the lack of significant survival improvement among those patients aged ≥ 70 years.

Mutations of EGFR or KRAS and expression of chemotherapy-related genes based on small biopsy samples in stage IIIB and IV inoperable non-small cell lung cancer

PURPOSES

Epidermal growth factor receptor (EGFR) and KRAS mutations may predict the outcome of targeted drug therapy and also may be associated with the efficacy of chemotherapy in patients with non-small cell lung cancer (NSCLC). This report investigated the relation of EGFR or KRAS mutation and expression of chemotherapy-related genes, including excision repair cross-complementing 1 (ERCC1), thymidylate synthetase (TYMS), ribonucleotide reductase subunit M1 (RRM1) and class III β-tubulin (TUBB3), as a potential explanation for these observations.

METHODS

A total of 143 patients with stage IIIB and IV NSCLC from bronchoscopy or percutaneous lung biopsy obtained tumor samples were analyzed concurrently for EGFR or KRAS mutations, and mRNA expression of ERCC1, TYMS, RRM1 and TUBB3. EGFR or KRAS mutations were detected with xTAG liquidchip technology (xTAG-LCT), and mRNA expression levels of four genes were detected by branched DNA-liquidchip technology (bDNA-LCT).

RESULTS

Of 143 patients, 63 tumors were positive for EGFR-activating mutations, and 16 tumors were positive for KRAS mutations. EGFR-activating mutations are more frequent in females, adenocarcinoma and non-smokers patients, and KRAS mutations are more frequent in smoking patients. ERCC1 mRNA levels were significantly associated with histological type and tumor differentiation, whereas TYMS levels were significantly associated with age. NSCLC specimens that harboring EGFR-activating mutations are more likely to express low ERCC1 and high TUBB3 mRNA levels, whereas tumors from patients with NSCLC harboring KRAS mutation are more likely to express high ERCC1 mRNA levels.

CONCLUSIONS

Mutations and expression of chemotherapy-related genes may provide a basis for the selection of suitable molecular markers for individual treatment in a population with stage IIIB and IV NSCLC.