Upfront gefitinib/erlotinib treatment followed by concomitant radiotherapy for advanced lung cancer: a mono-institutional experience

Prognosis evaluation and efficacy analysis of different treatment options for patients with visceral pleural invasion in stage IIA-IIB lung cancer

OBJECTIVE

Controversy surrounds the treatment of visceral pleural invasion in lung cancer, and no studies have compared the efficacy of its four main treatment options (i.e., surgery, chemotherapy, targeted therapy, and immunotherapy). This study aims to compare and analyze surgery, chemotherapy, targeted therapy, and immunotherapy outcomes and explore the optimal treatment of visceral pleural invasion in lung cancer.

METHODS

We searched electronic databases (i.e., Pubmed, Embase, Cochrane Library, CNKI, and Chinese Biomedical Literature Database Search) for relevant studies of treatment options for patients with visceral pleural invasion in stage IIA-IIB lung cancer. Searches times were limited to studies published between January 1, 2000 and February 20, 2021. Meta analysis was performed using RevMan 5.3 software We also downloaded original RNA transcription data about lung cancer invasion in the GEO and TCGA tumor databases, and used R 4.0.3 software to perform differential expression and co-expression gene network analyses.

RESULTS

We included a total of 25 high-quality (i.e., Jadad score 4-7) studies. Meta-analysis found that surgical treatment was associated with a 3-year survival rate OR = 3.80 (95% CI 3.53, 4.09; P < 0.0001), 5-year survival rate OR = 4.10 (95% CI 3.72, 4.53; P < 0.0001), and median survival time OR = 2.71 (95% CI 2.53, 2.89; P < 0.0001). Chemotherapy was associated with a 3-year survival rate OR = 2.08 (95% CI 1.93, 2.25; P < 0.0001), 5-year survival rate OR = 1.68 (95% CI 1.49, 1.89; P < 0.0001), and median survival time OR = 1.84 (95% CI 1.66, 2.04; P < 0.0001). Targeted therapy was associated with a 3-year survival rate OR = 2.91 (95% CI 2.65, 3.19; P < 0.0001), 5-year survival rate OR = 1.83 (95% CI 1.39, 2.33; P < 0.0001), and median survival time OR = 1.76 (95% CI 1.59, 1.94; P < 0.0001). Finally, immunotherapy was associated with a 3-year survival rate OR = 1.89 (95% CI 1.73, 2.07; P < 0.0001), 5-year survival rate OR = 1.66 (95% CI 1.46, 1.88; P < 0.0001), and median survival time OR = 2.53 (95% CI 2.27, 2.82; P < 0.0001). After screening differential genes and co-expressed genes in tumor gene databases, we found that AC245595.1, ITGB1-DT and AL606489.1 may be involved in the process of lung cancer invasion, and macrophages M1 and M2, CD4+-Th1, CD8+-Th1 may participate in immune infiltration.

CONCLUSIONS

In patients with visceral pleural invasion of stage IIA-IIB lung cancer, chemotherapy has shown a significant effect on improving prognosis and enhancing efficacy. However, surgical treatment did not significantly improve the overall prognosis. Therefore, the individual situation of the patient and the comprehensive benefits of the treatment program should be fully considered when developing the treatment program.

Appropriate delay of primary tumour radiotherapy may lead to better long-term overall survival for non-small cell lung cancer treated with EGFR-TKIs

PURPOSE

The most appropriate time of primary tumor radiotherapy in non-small cell lung cancer(NSCLC) with EGFR-TKIs remains unclear. The aim of this study was to investigate the effect of the time factor of primary tumor radiotherapy on long-term overall survival(OS)and provide a theoretical basis for further clinical research.

PATIENTS AND METHODS

In total, 238 patients with EGFR-TKIs and OS ≥ 12 months were statistically analysed. Patients were grouped: the D group without primary tumor radiotherapy and the R group with it.The R group were divided into three groups according to the interval between the start of EGFR-TKIs and the start of primary tumor radiotherapy: R0 - 30(<30 days), R30 - PD(≥ 30 days and disease stable), and RPD(radiotherapy after disease progression). The Kaplan-Meier method and log-rank test were used for survival analyses. Exploratory landmark analyses were investigated.

RESULTS

The OS rates at 1, 2, 3, 5 years for the R group and D group were 96.8%, 62.9%, 38.3%, 17.1%, and 95.6%, 37.7%, 21.8%, 2.9%, respectively; the corresponding MST was 29 months(95% CI: 24.3-33.7) for the R group and 22 months(95% CI: 20.4-23.6) for the D group (χ2 = 13.480, p<0.001). Multivariate analysis revealed that primary tumor radiotherapy was independent predictors of prolonged OS.Among the four groups, The R30 - PD appeared to have the best OS (D, χ2 = 19.307, p<0.001;R0 - 30, χ2 = 11.687, p = 0.01; RPD, χ2 = 4.086, p = 0.043). Landmark analyses(22 months) showed the R30 - PD group had a significant long-term OS.The incidence of radiation pneumonitis ≥ grade 2 was17.3%(n = 19)and radiation esophagitis ≥ grade 2 was observed in 32 patients(29.1%).

CONCLUSIONS

Our results showed that primary tumour radiotherapy may prolong long-term OS with acceptable toxicities. Appropriate delay(R30 - PD)of primary tumour radiotherapy may be the best choice.Premature radiotherapy(R0 - 30) and radiotherapy after disease progression (RPD)may not be reasonable for long-term OS.

T790M mutation sensitizes non-small cell lung cancer cells to radiation via suppressing SPOCK1

Background

Approximately 50% of patients harbor the T790M mutation after developing first-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) resistance. Evidence has showed the major treatment failure is local relapses and limited metastases. Several studies have demonstrated the value of radiotherapy in metastatic non-small cell lung cancer (NSCLC) with the EGFR T790M mutation after the development of TKI resistance. The aim of this study was to explore the role of radiation in T790M-mutant NSCLC and the value of early radiotherapy for NSCLC with T790M-mediated EGFR-TKI resistance.

Methods

Gefitinib-resistant NSCLC cell lines were established via stepwise exposure to increasing concentrations of gefitinib (PC-9-GR). Droplet digital PCR was used to determine the relative T790M subclone abundance. In vitro and in vivo models were established using different mixtures of PC-9-GR and PC-9 cells. Differentially expressed genes were identified using RNA sequencing. Two research models were constructed (salvage and prophylactic radiotherapy) to determine the effects of early radiotherapy on gefitinib-resistant cells.

Results

PC-9-GR cells exhibited higher radiosensitivity than PC-9 cells (sensitivity enhancement ratio = 1.5). Salvage radiation reduced the number of T790M-mutant subclones, and the relative T790M abundance was significantly lower than that without radiation at 90 days (10.94% vs. 21.54%). Prophylactic radiation prevented the development of T790M subclones. These results were also confirmed in vivo. qRT-PCR revealed threefold elevation of miR-1243 in PC-9-GR cells, and the increased radiosensitivity of PC-9-GR cells was inhibited when miR-1243 was knocked down. RNA sequencing revealed that SPOCK1 was downregulated in PC-9-GR cells. Interestingly, bioinformatic analysis showed that SPOCK1 was a target gene of miR-1243. SPOCK1 knockdown markedly increased the radiosensitivity of PC-9 cells.

Conclusion

Gefitinib-resistant NSCLC with the T790M mutation had higher radiosensitivity than that without the mutation, possibly mediated by SPOCK1. Early radiotherapy can eliminate T790M subclones, providing evidence for the benefit of early local treatment in patients with TKI-resistant NSCLC.

The incidence of and risk factors for radiation pneumonitis in patients treated with simultaneous bevacizumab and thoracic radiotherapy

BACKGROUND

First-line chemotherapy combined with bevacizumab is one of the standard treatment modes for patients with advanced non-small cell lung cancer (NSCLC). Thoracic radiotherapy (TRT) can provide significant local control and survival benefits to patients during the treatment of advanced NSCLC. However, the safety of adding TRT has always been controversial, especially because of the occurrence of radiation pneumonia (RP) during bevacizumab treatment. Therefore, in this study, we used an expanded sample size to evaluate the incidence of RP when using bevacizumab in combination with TRT.

PATIENTS AND METHODS

Using an institutional query system, all medical records of patients with NSCLC who received TRT during first-line chemotherapy combined with bevacizumab from 2017 to 2020 at Shandong Cancer Hospital and Institute were reviewed. RP was diagnosed via computed tomography and was classified according to the RTOG toxicity scoring system. The risk factors for RP were identified using univariate and multivariate analyses. The Kaplan-Meier method was used to calculate progression-free survival (PFS) and overall survival (OS).

RESULTS

Ultimately, 119 patients were included. Thirty-eight (31.9%) patients developed Grade ≥ 2 RP, of whom 27 (68.1%) had Grade 2 RP and 11 (9.2%) had Grade 3 RP. No patients developed Grade 4 or 5 RP. The median time for RP occurrence was 2.7 months (range 1.2-5.4 months). In univariate analysis, male, age, KPS score, V20 > 16.9%, V5 > 33.6%, PTV (planning target volume)-dose > 57.2 Gy, and PTV-volume > 183.85 cm3 were correlated with the occurrence of RP. In multivariate analysis, male, V20 > 16.9%, and PTV-volume > 183.85 cm3 were identified as independent predictors of RP occurrence. The mPFS of all patients was 14.27 (95% CI, 13.1-16.1) months. The one-year and two-year PFS rates were 64.9% and 20.1%, respectively. The mOS of all patients was 37.09 (95% CI, 33.8-42.0) months. The one-year survival rate of all patients was 95%, and the two-year survival rate was 71.4%.

CONCLUSIONS

The incidence of Grade ≥ 2 RP in NSCLC patients who received both bevacizumab and TRT was 31.9%. Restricting factors such as V20 and PTV will help reduce the risk of RP in these patients. For patients who receive both bevacizumab and TRT, caution should be exercised when increasing TRT, and treatment strategies should be optimized to reduce the incidence of RP.

Prognostic implications of combining EGFR-TKIs and radiotherapy in Stage IV lung adenocarcinoma with 19-Del or 21-L858R mutations: A real-world study

OBJECTIVE

To elucidate the potential benefits of combining radiotherapy and epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) for individuals with Stage IV lung adenocarcinoma (LUAD) harboring either exon 19 deletion (19-Del) or exon 21 L858R mutation (21-L858R).

METHODS

In this real-world retrospective study, 177 individuals with Stage IV LUAD who underwent EGFR-TKIs and radiotherapy at Shandong Cancer Hospital from June 2012 to August 2017 were included. The main focus of this real-world study was overall survival (OS).

RESULTS

The clinical characteristics of patients with Stage IV LUAD harboring 19-Del were similar to those harboring 21-L858R (p > 0.05). Overall, the patients had a median OS (mOS) of 32.0 months (95% confidence interval [CI]: 28.6-35.5). Subsequently, multivariate analysis indicated that both EGFR mutations and thoracic radiotherapy were independent predictors of OS (p = 0.001 and 0.013). Furthermore, subgroup analysis highlighted a longer OS for the 19-Del group compared to the 21-L858R group, especially when EGFR-TKIs were combined with bone metastasis or thoracic radiotherapy (mOS: 34.7 vs. 25.1 months and 51.0 vs. 29.6 months; p = 0.0056 and 0.0013, respectively). However, no significant differences were found in OS when considering patients who underwent brain metastasis radiotherapy (mOS: 34.7 vs. 25.1 months; p = 0.088).

CONCLUSIONS

Patients with Stage IV LUAD harboring 19-Del experience a notably prolonged OS following combined therapy with EGFR-TKIs and radiotherapy, while this OS benefit is observed despite the absence of substantial differences in the clinical characteristics between the 19-Del and 21-L858R groups.

Impact of thoracic tumor radiotherapy on survival in non-small-cell lung cancer with malignant pleural effusion treated with targeted therapy: Propensity score matching study

BACKGROUND

EGFR-mutant (EGFR-M) and ALK-positive (ALK-P)are common in malignant pleural effusion (MPE) with metastatic non-small-cell lung cancer (NSCLC) (MPE-NSCLC). The impact of thoracic tumor radiotherapy on survival in such patients remains unclear. We aimed to investigate whether thoracic tumor radiotherapy could improve overall survival (OS) in such patients.

METHODS

According to whether or not patients accepted thoracic tumor radiotherapy, 148 patients with EGFR-M or ALK-P MPE-NSCLC treated with targeted therapy were classified into two groups: DT group without thoracic tumor radiotherapy and DRT group with thoracic tumor radiotherapy. Propensity score matching (PSM) was performed to balance clinical baseline characteristics. Overall survival was analyzed by Kaplan-Meier, compared by log-rank test, and evaluated using Cox proportional hazards model.

RESULTS

Median survival time (MST) was 25 months versus 17 months in the DRT group and DT group. The OS rates at 1, 2, 3, 5 years in the DRT group and DT group were 75.0%, 52.8%, 26.8%, 11.1% and 64.5%, 28.4%, 9.2%, 1.8%, respectively (χ2  = 12.028, p = 0.001). Compared with DT group, the DRT group still had better survival after PSM (p = 0.007). Before and after PSM, factors associated with better OS through multivariable analysis were that thoracic tumor radiotherapy, radiotherapy, N0-2 , and ALK-TKIs. Grades 4-5 radiation toxicities were not observed in patients; 8 (11.6%) and 7 (10.1%) out of the DRT group suffered from Grade 3 radiation esophagitis and radiation pneumonitis, respectively.

CONCLUSION

Our results for EGFR-M or ALK-P MPE-NSCLC showed that thoracic tumor radiotherapy may be crucial factor in improving OS with acceptable toxicities. Potential biases should not be neglected: Further randomized controlled trials are necessary to confirm this result.

Re-evaluating the risk factors for radiation pneumonitis in the era of immunotherapy

As one of the common complications of radiotherapy, radiation pneumonia (RP) limits the prognosis of patients. Therefore, better identifying the high-risk factors that lead to RP is essential to effectively prevent its occurrence. However, as lung cancer treatment modalities are being replaced and the era of immunotherapy has arrived, literature that reviews the parameters and mode of radiotherapy, chemotherapy drugs, targeted drugs and current hot immune checkpoint inhibitors related to RP is lacking. This paper summarizes the risk factors for radiation pneumonia by retrieving and analysing previously published literature and the results of large clinical trials. The literature primarily included retrospective analyses, including clinical trials in different periods and a part of the literature review. A systematic literature search of Embase, PubMed, Web of Science, and Clinicaltrials.gov was performed for relevant publications up to 6 Dec. 2022. Search keywords include, but are not limited to, "radiation pneumonia", "pneumonia", "risk factors", "immunotherapy", etc. The factors related to RP in this paper include physical parameters of radiotherapy, including V₅, V₂₀, and MLD; chemoradiotherapy mode and chemotherapy drugs, including paclitaxel and gemcitabine; EGFR-TKI; ALK inhibitors; antiangiogenic drugs; immune drugs and the underlying disease of the patient. We also introduce the possible mechanism of RP. In the future, we hope that this article not only sounds the alarm for clinicians but also helps to identify a method that can effectively intervene and reduce the occurrence of RP, significantly improve the quality of life and prognosis of patients, and more effectively improve the therapeutic effect of radiation therapy.

Non-Small Cell Lung Cancer Treatment with Molecularly Targeted Therapy and Concurrent Radiotherapy—A Review

Lung cancer is the leading cause of death worldwide for both men and women. Surgery can be offered as a radical treatment at stages I and II and selected cases of stage III (III A). Whereas at more advanced stages, combined modalities of treatment are applied: radiochemotherapy (IIIB) and molecularly targeted treatment (small molecule tyrosine kinase inhibitors, VEGF receptor inhibitors, monoclonal antibodies, and immunological treatment with monoclonal antibodies). Combination treatment, composed of radiotherapy and molecular therapy, is increasingly employed in locally advanced and metastatic lung cancer management. Recent studies have indicated a synergistic effect of such treatment and modification of immune response. The combination of immunotherapy and radiotherapy may result in the enhancement of the abscopal effect. Anti-angiogenic therapy, in combination with RT, is associated with high toxicity and should be not recommended. In this paper, the authors discuss the role of molecular treatment and the possibility of its concurrent use with radiotherapy in non-small cell lung cancer (NSCLC).

Comparison of the Incidence Rate of Radiation Pneumonitis Observed in Patients with Advanced Lung Adenocarcinoma Treated with Simultaneous Thoracic Radiotherapy and 1G/2G/3G EGFR-TKIs

Purpose

The present study aimed to evaluate the incidence rate of radiation pneumonitis (RP) in patients with advanced lung adenocarcinoma treated with first-generation (1G), second-generation (2G), or third-generation (3G) epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) combined with thoracic radiotherapy (TRT).

Patients and Methods

Patients with advanced lung adenocarcinoma simultaneously treated with 1G/2G/3G EGFR-TKIs and TRT between 2015-2021 at Shandong Cancer Hospital and Institute were screened. The incidence rate of clinical and imaging RP was compared between the three groups.

Results

A total of 200 patients treated with EGFR-TKIs were enrolled in this study, including 100 patients who were treated with 1G EGFR-TKIs, 50 patients who were treated with 2G EGFR-TKIs, and 50 patients who were treated with 3G EGFR-TKIs (patients matched in a 2:1:1 ratio for tumor characteristics). The overall incidence of clinical RP in the 1G, 2G, and 3G EGFR-TKI groups were 29%, 48%, and 28% (p=0.043), respectively, and that of imaging RP were 33%, 58%, and 36% (p=0.010), respectively. The incidence of RP with a clinical grade ≥3 in the three groups were 14%, 28%, and 12% (p=0.055), respectively, and that with an imaging grade ≥3 in the three groups were 11%, 32%, and 10% (p=0.002), respectively. The incidence of clinical RP was higher in the CFRT group than in the SBRT group, with an overall clinical grade of 38% vs 10% (p<0.001) and imaging grade of 46% vs 10% (p<0.001), respectively. In the multivariate analysis, only GTV volume was an independent predictive factor for all risks of clinical and imaging RP. V20 and grouping of 1G/2G/3G EGFR-TKIs were other independent predictive factors for the risk factors of RP for imaging grades.

Conclusion

Compared with 2G EGFR-TKIs combined with TRT, 1G or 3G EGFR-TKIs combined with TRT achieved a lower incidence of RP.

Symptomatic Radiation Pneumonitis in NSCLC Patients Receiving EGFR-TKIs and Concurrent Once-daily Thoracic Radiotherapy: Predicting the Value of Clinical and Dose-volume Histogram Parameters

BACKGROUND

The incidence of symptomatic radiation pneumonitis (RP) and its relationship with dose-volume histogram (DVH) parameters in non-small cell lung cancer (NSCLC) patients receiving epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) and concurrent once-daily thoracic radiotherapy (TRT) remain unclear. We aim to analyze the values of clinical factors and dose-volume histogram (DVH) parameters to predict the risk for symptomatic RP in these patients.

METHODS

Between 2011 and 2019, we retrospectively analyzed and identified 85 patients who had received EGFR-TKIs and once-daily TRT simultaneously (EGFR-TKIs group) and 129 patients who had received concurrent chemoradiotherapy (CCRT group). The symptomatic RP was recorded according to the Common Terminology Criteria for Adverse Event (CTCAE) criteria (grade 2 or above). Statistical analyses were performed using SPSS 26.0.

RESULTS

In total, the incidences of symptomatic (grade≥2) and severe RP (grade≥3) were 43.5% (37/85) and 16.5% (14/85) in EGFR-TKIs group vs 27.1% (35/129) and 10.1% (13/129) in CCRT group respectively. After 1:1 ratio between EGFR-TKIs group and CCRT group was matched by propensity score matching, chi-square test suggested that the incidence of symptomatic RP in the MATCHED EGFR-TKIs group was higher than that in the matched CCRT group (χ2=4.469, P=0.035). In EGFR-TKIs group, univariate and multivariate analyses indicated that the percentage of ipsilateral lung volume receiving ≥30 Gy (ilV30) [odds ratio (OR): 1.163, 95%CI: 1.036-1.306, P=0.011] and the percentage of total lung volume receiving ≥20 Gy (tlV20) (OR: 1.171, 95%CI: 1.031-1.330, P=0.015), with chronic obstructive pulmonary disease (COPD) or not (OR: 0.158, 95%CI: 0.041-0.600, P=0.007), were independent predictors of symptomatic RP. Compared to patients with lower ilV30/tlV20 values (ilV30 and tlV20<cut-off point values) and without COPD, patients with higher ilV30/tlV20 values (ilV30 and tlV20>cut-off point values) and COPD had a significantly higher risk for developing symptomatic RP, with a hazard ratio (HR) of 1.350 (95%CI: 1.190-1.531, P<0.001).

CONCLUSIONS

Patients receiving both EGFR-TKIs and once-daily TRT were more likely to develop symptomatic RP than patients receiving concurrent chemoradiotherapy. The ilV30, tlV20, and comorbidity of COPD may predict the risk of symptomatic RP among NSCLC patients receiving EGFR-TKIs and conventionally fractionated TRT concurrently.

Local Therapy Combined With First-Line EGFR Tyrosine Kinase Inhibitor Achieves Favorable Survival in Patients With EGFR-Mutant Metastatic Non-Small Cell Lung Cancer

BACKGROUND

EGFR tyrosine kinase inhibitor (TKI) is recommended as the first-line therapy for patients with EGFR-mutant metastatic non-small cell lung cancer (NSCLC). Yet, resistance often occurs in 1 year after therapy and most progressions occur at the initial sites of disease. Addition of local therapy to the first-line TKI therapy may delay the progression and provide survival benefit to the patients.

METHODS

From 2010 to 2017, metastatic NSCLC patients with EGFR activating mutations who received first-line TKI and relatively radical local therapy (RRLT) were reviewed. RRLT was defined as local curative therapy to the main site or any intensity of local therapy to all sites of disease. The Kaplan-Meier method and log-rank test were used for survival estimation and comparison.

RESULTS

A total of 45 patients were included in this retrospective study with a median follow-up of 48.0 months. The median progression-free survival (PFS) and overall survival (OS) was 17.0 months (95% confidence interval [CI]: 14.6-19.3) and 55.0 months (95% CI: 49.3-60.6), respectively. Univariate analysis indicated that age ⩽ 60 years (P = .019), first-line TKI duration ⩾ 10 months (P = .028), and accumulated TKI duration ⩾ 20 months (P = .016) were significantly associated with favorable OS. Among the 36 patients who progressed during the follow-up, 55.8% of the progressions occurred at the new sites. RRLT combined with TKI did not show any severe toxicity to the patients.

CONCLUSIONS

Combined application of RRLT and first-line TKI may improve the survival and alter the pattern of failure for metastatic NSCLC patients with EGFR activating mutations.

EGFR-mutated stage IV non-small cell lung cancer: What is the role of radiotherapy combined with TKI?

Lung cancer is the leading cause of cancer-related death globally and poses a considerable threat to public health. Asia has the highest prevalence of epidermal growth factor receptor (EGFR) mutations in patients with non-small cell lung cancer (NSCLC). Despite the reasonable response and prolonged survival associated with EGFR-tyrosine kinase inhibitor (TKI) therapy, the acquisition of resistance to TKIs remains a major challenge. Additionally, patients with EGFR mutations are at a substantially higher risk of brain metastasis compared with those harboring wild-type EGFR. The role of radiotherapy (RT) in EGFR-mutated (EGFRm) stage IV NSCLC requires clarification, especially with the advent of next-generation TKIs, which are more potent and exhibit greater central nervous system activity. In particular, the feasible application of RT, including the timing, site, dose, fraction, and combination with TKI, merits further investigation. This review focuses on these key issues, and provides a flow diagram with proposed treatment options for metastatic EGFRm NSCLC, aiming to provide guidance for clinical practice.

Overlap time is an independent risk factor of radiation pneumonitis for patients treated with simultaneous EGFR-TKI and thoracic radiotherapy

Background

The exact rate and relevant risk factors of radiation pneumonitis (RP) for non-small-cell cancer (NSCLC) patients treated with the combination of epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) and thoracic radiotherapy have not been reported. Thus, this study aimed to investigate the rate and risk factors of RP for EGFR-positive NSCLC patients simultaneously treated with first-generation EGFR-TKI and TRT.

Patients and methods

We retrospectively evaluated NSCLC patients simultaneously treated with first-generation EGFR-TKI and thoracic radiotherapy between January 2012 and December 2019 at Shandong Cancer Hospital and Institute, Shandong, China. RP was diagnosed via computed tomography and was classified according to the Common Terminology Criteria for Adverse Events v5.0. The risk factors of RP were identified using uni- and multivariate analyses.

Results

Of the 67 patients included, 44.78% (30/67) developed grade ≥ 2 RP. Grade ≥ 2 RP occurred within a median of 3.48 (range 1.07–13.6) months. The EGFR-TKI icotinib, ipsilateral lung V30 > 34%, and overlap time of > 20 days between EGFR-TKI and thoracic radiotherapy were identified to be independent predictive factors of grade ≥ 2 RP.

Conclusions

Grade ≥ 2 RP is highly frequent in NSCLC patients simultaneous treated with first-generation EGFR-TKI and thoracic radiotherapy. Icotinib, ipsilateral lung V30 ≤ 34%, and overlap time of ≤ 20 days for EGFR-TKI and thoracic radiotherapy will be helpful to lower the risk of RP in these patients. The addition of thoracic radiotherapy should be cautious, and the treatment strategies can be optimized to reduce the rate of RP for patients treat with simultaneous EGFR-TKI and thoracic radiotherapy.

Management of medically inoperable and tyrosine kinase inhibitor-naïve early-stage lung adenocarcinoma with epidermal growth factor receptor mutations: a retrospective multi-institutional analysis

Background

The clinical value of combined local radiation and epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors (TKIs) for medically inoperable and TKI-naïve early-stage lung adenocarcinoma patients with EGFR mutations has not yet been determined. In this study, we aimed to pool multi-institutional data to compare the therapeutic effect of EGFR-TKI treatment alone and combined radiation and TKI treatment on the survival outcomes in this patient subgroup.

Methods

A total of 132 cases of medically inoperable stage I to III EGFR mutant lung adenocarcinoma were retrospectively reviewed based on data from 5 centers. Among these patients, 65 received combined radiation and EGFR-TKI therapy (R + TKI) (49.2%), while 67 received EGFR-TKI (50.8%) treatment alone. All patients were followed until death.

Results

For the R + TKI group, the median overall survival (OS) after primary therapy was 42.6 months, while that of the TKI alone group was 29.4 months (log-rank p < 0.001). In terms of progression-free survival (PFS), the median PFS in these two treatment groups was 24 months and 14.7 months respectively (log-rank p < 0.001). Multivariate analysis showed that R + TKI was independently associated with improved OS (adjusted HR 0.420; 95% CI 0.287 to 0.614; p < 0.001) and PFS (adjusted HR 0.420; 95% CI 0.291 to 0.605; p < 0.001) compared to TKI alone. Subgroup analysis confirmed the significant OS benefits in stage III patients and RFS benefits in stage II/III patients.

Conclusions

Upfront radiation to primary sites with subsequent TKI treatment is a feasible option for patients with medically inoperable EGFR-mutant non-small-cell lung carcinoma (NSCLC) during first-line EGFR-TKI treatment, with significantly improved PFS and OS compared with those yielded by TKI treatment alone.

Radiotherapy combined with gefitinib for patients with locally advanced non-small cell lung cancer who are unfit for surgery or concurrent chemoradiotherapy: a phase II clinical trial

Background

The objectives of this study were to determine the objective effective response rate, survival, and safety of radiotherapy combined with gefitinib in patients with locally advanced non-small cell lung cancer (NSCLC) who were unfit for surgery or concurrent chemoradiotherapy.

Methods

The patients with the locally advanced NSCLC who were unfit to receive surgery or concurrent chemoradiotherapy, received thoracic intensity-modulated radiotherapy (IMRT) combined with gefitinib 250 mg daily.

Results

29 patients were enrolled between July 2014 and March 2017. 28 patients was in the analysis. Of the 28 patients, 21 (75.0%) experienced a partial response, 5 (17.9%) had stable disease, and 2 (7.1%) experienced progression of disease. The objective response rate was 75.0%, and the disease control rate was 92.9%. The median follow-up time was 51 months. The disease progression showed in 25 (89.3%) patients, including local progression in 19 (67.9%) and distant metastasis in 16 (57.1%). The median overall survival and progression-free survival time (PFS) were 26 and 11 months, respectively. The 3-, 4-, 5-year survival rates were 39.0, 30.1 and 30.1%, respectively. The 3-, 4-, 5-year PFS rates were 14.3, 9.5 and 9.5%. Two patients developed grade 3 acute adverse events. Seven patients developed grade 2 acute irradiation pneumonitis, and there was no grade 3 acute irradiation pneumonitis.

Conclusions

For patients with locally advanced NSCLC who are not eligible for surgery or concurrent chemoradiotherapy, IMRT combined with gefitinib can improve the objective effective rate and is generally well-tolerated.

Pattern of Recurrence Analysis in Metastatic EGFR-Mutant NSCLC Treated with Osimertinib: Implications for Consolidative Stereotactic Body Radiation Therapy

PURPOSE

Despite the impressive response rate to osimertinib, acquired resistance remains an obstacle to achieving long-term tumor control in metastatic epidermal growth factor receptor-mutant non-small cell lung cancer. Stereotactic body radiation therapy (SBRT) plays a growing role in the management of oligometastatic disease. We investigated the patterns of residual disease and progression on osimertinib, as well as the predictors of candidates for consolidative SBRT.

METHODS AND MATERIALS

The serial scans of patients with metastatic epidermal growth factor receptor-mutant non-small cell lung cancer treated with osimertinib were retrospectively reviewed. Disease progression in residual sites, new sites, and both residual and new sites were classified as residual-site recurrence (RR), new-site recurrence (NR), and combined RR and NR (RNR), respectively. Logistic regression analysis was performed to identify predictors of candidates for consolidative SBRT.

RESULTS

Ninety-seven patients were enrolled. The median time to maximal osimertinib response was 2.6 months. Twenty-six patients (26.8%) with oligoresidual disease were identified as candidates for consolidative SBRT at time of maximal response. Stage T1-2 before initiation of osimertinib (P = .046) was the independent predictor of consolidative SBRT eligibility. During a median follow-up of 10.9 months, disease progression was documented in 50 (51.5%) patients, and 70% of them experienced oligoprogression. Twenty-five (50%) patients developed disease progression in originally involved sites, 11 (22%) had new metastases, and 14 (28%) experienced disease progression in both original and new metastatic sites. Forty-six patients had progressive disease after experiencing initial stable disease or objective response to osimertinib. RR occurred in 20 (43.5%) of these patients, NR in 14 (30.4%), and RNR in 12 (26.1%). Notably, within the subgroup of patients eligible for consolidative SBRT, RR was observed in 6 (54.5%) patients, RNR in 3 (27.3%), and NR in 2 (18.2%).

CONCLUSIONS

The majority of progressive disease on osimertinib was within residual lesions in initially involved sites. Consolidative SBRT may prolong time to progression in a selected subgroup of patients, which merits further investigation.

Efficacy of early combination of local radiotherapy and GM-CSF for advanced non-small cell lung cancer treated with icotinib

BACKGROUND

Lung cancer is a disease that severely endangers human health. Non-small cell lung cancer (NSCLC) accounts for approximately 4/5 of lung cancers.

AIMS

To investigate the efficacy of early combination of local radiotherapy and granulocyte macrophage colony-stimulating factor (GM-CSF) for advanced NSCLC treated with icotinib.

METHODS

Forty-two patients with stage IV NSCLC complicated with EGFR gene mutation were selected and randomly divided into two groups, with 21 patients in each group. Patients in control group were treated with icotinib, and patients in experimental group were treated with icotinib combined with local radiotherapy and subcutaneous injection of GM-CSF. One-year progression free survival between two groups was compared.

RESULTS

Three months after treatment, the efficacy in experimental group was significantly better than that in control group, and objective response rate was 95.24% in experimental group, which was higher than the 71.43% in control group. Patients in experimental group had no differences in white blood cell and neutrophil, but had significantly lower carcino-embryonic antigen and neuron-specific enolase levels and higher CD3+, CD4+, and CD4+/CD8+ than those in control group and before treatment. There were no differences in the proportion of patients with adverse reactions between two groups. One-year progression free survival was significantly better in experimental group than in control group.

CONCLUSIONS

Early combination of local radiotherapy and GM-CSF has a significant efficacy for advanced NSCLC accounts for approximately 4/5 of lung cancers treated with icotinib, and it can improve patients' autoimmunity and lengthen progression free survival.

Radiation-Induced Lung Injury (RILI)

Radiation pneumonitis (RP) and radiation fibrosis (RF) are two dose-limiting toxicities of radiotherapy (RT), especially for lung, and esophageal cancer. It occurs in 5-20% of patients and limits the maximum dose that can be delivered, reducing tumor control probability (TCP) and may lead to dyspnea, lung fibrosis, and impaired quality of life. Both physical and biological factors determine the normal tissue complication probability (NTCP) by Radiotherapy. A better understanding of the pathophysiological sequence of radiation-induced lung injury (RILI) and the intrinsic, environmental and treatment-related factors may aid in the prevention, and better management of radiation-induced lung damage. In this review, we summarize our current understanding of the pathological and molecular consequences of lung exposure to ionizing radiation, and pharmaceutical interventions that may be beneficial in the prevention or curtailment of RILI, and therefore enable a more durable therapeutic tumor response.

Increase of secondary mutations may be a drug-resistance mechanism for lung adenocarcinoma after radiation therapy combined with tyrosine kinase inhibitor

Objective: To investigate changes in the secondary mutations of tumor in a drug-resistance mechanism for lung adenocarcinoma after radiation therapy combined with tyrosine kinase inhibitor (TKI). Methods: Lung adenocarcinoma cell line PC9 in vitro and xenograft model in nude mice were used to observe tumor inhibitory effects and drug-resistance under the effect of radiation therapy combined with erlotinib through apoptosis detection through in vitro survival curve and in vivo growth curve; changes in gene mutations before and after drug-resistance in nude mice xenografts were observed by the next generation sequencing, and the relationship between cancer drug-resistance and radiation therapy combined with TKI was observed. Results: Radiation therapy combined with erlotinib had a more reliable radio-sensitizing effect in vitro and in vivo, however, there were several drug-resistant tumor cells. Meanwhile, radiation therapy combined with erlotinib could significantly increase the number of mutations in tumor genes. The whole genome sequencing showed that the secondary mutation in the combined treatment group significantly increased in comparison with those of the single treatment group and the blank control group. Conclusion: The increase of secondary mutations may be an important drug-resistance mechanism for lung adenocarcinoma after radiation therapy combined with TKI, which provided further space exploration under the combined action of radiation and TKI.

Epidermal growth factor receptor tyrosine kinase inhibitors combined with thoracic radiotherapy or chemoradiotherapy for advanced or metastatic non-small cell lung cancer: A systematic review and meta-analysis of single-arm trials

BACKGROUND

Preclinical in vitro experiments demonstrated that epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) might have synergistic effect in combination with radiotherapy on Non-small cell lung cancer (NSCLC), but the clinical trials showed inconsistence results in NSCLC patients with EGFR status unknow or mutations. This study aimed to determine if added TKIs to Thoracic radiotherapy (TRT) improve primary disease response rate (RR) and survival outcomes in advanced or metastatic NSCLC.

METHODS

We searched MEDLINE, EMBASE, and Cochrane Library from January 2000 to December 2017 for eligible studies where patients received concurrent EGFR TKIs and TRT or CRT. Concerned outcomes were primary tumor RR, overall survival (OS), and adverse events (AEs). The meta-analysis was performed using Stata software (version 12.0). Random effects models were used to pool outcomes across studies. Sensitivity analysis was performed to determine if the results would be different.

RESULTS

We found 16 prospective clinical trials with mature results for meta-analyses. Twelve studies including 446 patients reported the RR and survival outcomes of TRT combined TKIs. The CR, PR, SD, and PD, respectively, were 0.06 (95% CI 0.03-0.09, I = 0%), 0.44 (95% CI 0.38-0.49, I = 64.9%), 0.29 (95% CI 0.24-0.34, I = 78.4%), and 0.15 (95% CI 0.11-0.19, I = 84.2%). One- and 2-year OS, respectively, were 0.52 (95% CI 0.44-0.60, I = 38.8%) and 0.26 (95% CI 0.18-0.33, I = 0%). Four studies including 182 patients reported the RR and survival outcomes of CRT combined TKIs. The pooled CR, PR, SD, and PD, respectively, were 0.12 (95% CI 0.02-0.22, I = 69.1%), 0.41 (95% CI 0.27-0.55, I71.6%), 0.31 (95% CI 0.16-0.46, I = 79%), and 0.14 (95% CI -0.01-0.30, I = 87.8%). Only 1 study reported the survival event rate, 1- and 2-year OS, respectively, were 0.83 (95% CI 0.71-0.94) and 0.67 (95% CI 0.54-0.81). There were not severe adverse events (SAEs) reported either TRT combined TKIs or CRT combined TKIs.

CONCLUSION

There is evidence, albeit of low quality, that added the TKIs to TRT or CRT may improve RR and survival outcomes in patients with EGFR mutant status unknown advanced or metastatic NSCLC relative to other studies of TKIs alone, TRT alone or CRT.

Targeting DNA Double-Strand Break Repair Pathways to Improve Radiotherapy Response

More than half of cancer patients receive radiotherapy as a part of their cancer treatment. DNA double-strand breaks (DSBs) are considered as the most lethal form of DNA damage and a primary cause of cell death and are induced by ionizing radiation (IR) during radiotherapy. Many malignant cells carry multiple genetic and epigenetic aberrations that may interfere with essential DSB repair pathways. Additionally, exposure to IR induces the activation of a multicomponent signal transduction network known as DNA damage response (DDR). DDR initiates cell cycle checkpoints and induces DSB repair in the nucleus by non-homologous end joining (NHEJ) or homologous recombination (HR). The canonical DSB repair pathways function in both normal and tumor cells. Thus, normal-tissue toxicity may limit the targeting of the components of these two pathways as a therapeutic approach in combination with radiotherapy. The DSB repair pathways are also stimulated through cytoplasmic signaling pathways. These signaling cascades are often upregulated in tumor cells harboring mutations or the overexpression of certain cellular oncogenes, e.g., receptor tyrosine kinases, PIK3CA and RAS. Targeting such cytoplasmic signaling pathways seems to be a more specific approach to blocking DSB repair in tumor cells. In this review, a brief overview of cytoplasmic signaling pathways that have been reported to stimulate DSB repair is provided. The state of the art of targeting these pathways will be discussed. A greater understanding of the underlying signaling pathways involved in DSB repair may provide valuable insights that will help to design new strategies to improve treatment outcomes in combination with radiotherapy.

Research progress on the impact of radiation on TKI resistance mechanisms in NSCLC

Resistance to tyrosine kinase inhibitor (TKI) therapy is often accompanied by various genetic alterations, and radiation is an important weapon for changing the DNA of tumor cells. In radiotherapy combined with TKI therapy for non-small cell lung cancer (NSCLC), the two treatment strategies affect and interact with each other, resulting in complex tumor resistance mechanisms. Accordingly, tumor progression management after radiotherapy combined with TKI therapy should be different from that after TKI therapy alone. However, current clinical practice is entirely based on the resistance mechanisms of simple TKI therapy. Therefore, it is imperative to investigate the impact of radiation on the mechanism of TKI resistance. However, due to the complexity of the resistance mechanisms under the combined effect of both therapies, such studies remain extremely challenging and time-consuming.

Efficacy of thoracic radiotherapy in patients with stage IIIB-IV epidermal growth factor receptor-mutant lung adenocarcinomas who received and responded to tyrosine kinase inhibitor treatment

PURPOSE

Large-scale, prospective, randomized studies of the efficacy of thoracic radiotherapy (RT) in patients with unresectable stage IIIB-IV epidermal growth factor receptor (EGFR)-mutant lung adenocarcinomas who received and responded to EGFR tyrosine kinase inhibitor (TKI) treatment are not currently available. Therefore, we designed a propensity score-matched, nationwide, population-based, cohort study for estimating the effects of thoracic RT on patients with EGFR-mutant lung adenocarcinomas.

PATIENTS AND METHODS

We analyzed patients with unresectable stage IIIB-IV EGFR mutant lung adenocarcinomas and categorized them into two groups according to treatment modality and compared their outcomes; groups 1 and 2 consisted of patients who received EGFR TKI treatment alone until tumor progression and those who received and responded to EGFR TKI treatment and subsequently received thoracic RT for lung tumors, respectively. The patients in groups 2 and 1 were matched at a ratio of 1:4.

RESULTS

The matching process yielded a final cohort of 1475 patients (1180 and 295 patients in groups 1 and 2, respectively) who were eligible for further analysis. According to both univariate and multivariate Cox regression analyses, the adjusted hazard ratios (aHRs) (95% confidence interval [CI]) derived for thoracic RT for lung tumor after EGFR TKI use and tumor response (group 2) compared with EGFR TKI treatment alone (group 1) was 0.72 (0.60-0.85).

CONCLUSIONS

Thoracic RT might be associated with overall survival in patients with unresectable stage IIIB-IV EGFR-mutant lung adenocarcinomas who received and responded to EGFR TKI treatment.

MTOR inhibition reversed drug resistance after combination radiation with erlotinib in lung adenocarcinoma

Objective

To investigate the effects of mTOR inhibition on drug resistance in lung adenocarcinoma after combined radiation and erlotinib therapy.

Results

Combined radiation and erlotinib therapy produced clear radiosensitization effects both in vitro and in vivo; however, tumor cells remained drug resistant. Additionally, combined radiation and erlotinib therapy significantly increased p-AKT and p-P70 levels. After mTOR inhibition, the number of surviving cells significantly decreased compared with that before inhibition, and the in vivo growth curve was significantly reduced.

Methods

The effects of combined radiation and erlotinib therapy on tumor inhibition and drug resistance were evaluated by in vitro survival curves in PC9 lung adenocarcinoma cell line and in vivo growth curves in nude mouse xenograft tumor model respectively. The association between tumor drug resistance and the phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin (PI3K-AKT-mTOR) pathway was measured by western blot, assessing the changes in protein kinase B (AKT), phosphor-AKT (p-AKT), P70, and p-P70 protein levels. MTOR was inhibited using everolimus, and changes in AKT, p-AKT, P70, and p-P70 levels were observed. Furthermore, changes in in vitro survival curves, and in vivo growth curves before and after mTOR inhibition were evaluated to confirm its effects on drug resistance in lung adenocarcinoma after combined radiation and TKI therapy.

Conclusion

mTOR was associated with drug resistance in lung adenocarcinoma after radiation combined with TKI, and MTOR inhibition reversed drug resistance in lung adenocarcinoma after combined radiation and TKI therapy.

Management of non-small cell lung cancer with EGFR mutation: the role of radiotherapy in the era of tyrosine kinase inhibitor therapy-opportunities and challenges

In recent years, the treatment of advanced non-small cell lung cancer (NSCLC) was greatly promoted by the discovery of oncogenic drivers and the development of targeted therapies specific for these drivers. Somatic mutations in epidermal growth factor receptor (EGFR) are the most common type in patients with NSCLC. Small-molecule tyrosine kinase inhibitor (TKI) targeting EGFR produced relatively high response rate and long duration with acceptable toxicity profile. Also, the life expectancy in patients with active EGFR mutation has been significantly prolonged than the past. Additionally, evolution of advanced imaging and radiation techniques has expanded the indications for radiotherapy in complex clinical situation. All of those factors contributed to the widely use of radiotherapy for advanced NSCLC treated with TKI therapy. In this review, we will discuss how to integrate radiotherapy into the comprehensive treatment of patients with TKI therapy in order to maximize the therapeutics effect.

Continuous epidermal growth factor receptor-tyrosine kinase inhibitor administration in primary lung adenocarcinoma patients harboring favorable mutations with controlled target lung tumors dose not hinder survival benefit despite small new lesions

Background

In this study, we investigated the efficacy of continuous epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) administration in lung adenocarcinoma patients harboring favorable mutations regarding the progressive disease (PD) status with appearance of indolent new lesions.

Methods

From June 2010 to October 2012, 102 patients with lung adenocarcinoma, harboring favorable EGFR mutations and treated with EGFR-TKI were analyzed. Definite new lesions were detected during EGFR-TKI therapy, even though the primary target tumors were controlled.

Results

Of the 102 patients, 57 continued and 45 discontinued EGFR-TKI therapy. The median overall survival was 529 days for the discontinuation group and 791 days for the continuation group (p = 0.0197). Median survival time after the discontinuation of EGFR-TKI was 181 days and 115 days in the discontinuation and continuation groups, respectively (p = 0.1776), whereas median survival time after the appearance of indolent new lesions was 204 days and 262 days, respectively (p = 0.0237).

Conclusion

Continuous EGFR-TKI administration in favorable EGFR-mutative lung adenocarcinoma patients with controlled primary tumors did not hinder the survival benefit, despite the appearance of new lesions.

[Ionizing Radiation Reduces TKI Resistance Caused by T790M Mutation in NSCLC Cell Lines]

背景与目的

以表皮生长因子受体（epidermal growth factor receptor, EGFR）为靶点的分子靶向治疗在非小细胞肺癌（non-small cell lung cancer, NSCLC）的治疗中发挥重要的作用。EGFR突变的患者对EGFR酪氨酸激酶抑制剂（EGFR-tyrosine kinase inhibitor, EGFR-TKI）治疗敏感、疗效显著，但无论近期疗效如何，患者最终都不可避免地产生耐药。大量研究证实，EGFR基因的二次突变（T790M）是患者耐药的主要原因。本研究旨在探讨电离辐射对NSCLC细胞株T790M突变所致EGFR-TKI耐药的影响。

方法

选择NSCLC细胞株H1975和H3255为研究对象，实时荧光定量PCR法检测两株细胞的突变状态、克隆形成实验观察两株细胞的放射敏感性，MTT法检测各处理组两株细胞对EGFR-TKI的抗药性。

结果

H1975为T790M+L858R双突变株、H3255是仅有L858R的单突变株；各处理组H1975及H3255的存活分数未见明显差异（P=0.952），提示T790M突变对NSCLC细胞株的放射敏感性无影响；2.5 Gy X线辐射组，H1975的IC₅₀为（0.678, 2±0.373）μmol/L，较0 Gy对照组的（3.520±0.821）μmol/L明显下降，差异有统计学意义（P=0.008），H1975相较于H3255的抗药性也从85.9倍下降为39.2倍。

结论

电离辐射可降低NSCLC细胞株T790M突变所致的TKI耐药，本实验的研究结果为后续的体内和临床研究提供了研究依据；EGFR-TKI治疗期间联合放射治疗对克服T790M突变介导的耐药性有望成为一种有希望的治疗策略。

Radical thoracic radiotherapy may provide favorable outcomes for stage IV non-small cell lung cancer

BACKGROUND

This study investigates the outcome of synchronous stage IV non-small cell lung cancer (NSCLC) patients who received radical thoracic radiotherapy (TRT).

METHODS

We retrospectively reviewed the charts of stage IV NSCLC patients treated with TRT between January 2007 and December 2011. Radiotherapy was considered radical if it was the primary therapy with non-symptom driven intent, or consolidation therapy after initial chemotherapy and the biologically equivalent dose ≥53 Gy halted disease progression. The patients' demographics, disease characteristics, and treatment parameters were uniformly collected.

RESULTS

Eighty-one patients were irradiated with radical intent, including 52% with more than five metastatic lesions. The minimum follow-up was 31.5 months for survivors. The median overall survival (OS) was 20.8 months, with three and four-year OS rates of 23% and 18%, respectively. The median progression-free survival (PFS) was 8.2 months, with one and two-year PFS rates of 23% and 9%, respectively. Partial response (PR) after TRT and administration of targeted therapy were predictive of longer OS. The factors associated with favorable PFS included earlier local tunor node stage, absence of concurrent chemotherapy, and post-TRT PR. No correlation was found between the number of metastatic lesions and survival outcome. Incidences of grade ≥2 toxicities in the lung and esophagus were 9% and 26%, respectively.

CONCLUSIONS

Radical TRT may result in advantageous outcomes for selected stage IV NSCLC patients, regardless of the number of metastatic foci. Patients who achieved post-TRT PR attained the best outcomes.

Radiotherapy of non-small-cell lung cancer in the era of EGFR gene mutations and EGF receptor tyrosine kinase inhibitors

Non-small-cell lung cancer (NSCLC) occurs, approximately, in 80–85% of all cases of lung cancer. The majority of patients present locally advanced or metastatic disease when diagnosed, with poor prognosis. The discovery of activating mutations in the EGFR gene has started a new era of personalized treatment for NSCLC patients. To improve the treatment outcome in patients with unresectable NSCLC and, in particular, EGFR mutated, a combined strategy of radiotherapy and medical treatment can be undertaken. In this review we will discuss preclinical data regarding EGF receptor (EGFR) tyrosine kinase inhibitors (TKIs) and radiotherapy, available clinical trials investigating efficacy and toxicity of combined treatment (thoracic or whole brain radiotherapy and EGFR-TKIs) and, also, the role of local radiation in mutated EGFR patients who developed EGFR-TKI resistance.

Adding Erlotinib to Chemoradiation Improves Overall Survival but Not Progression-Free Survival in Stage III Non-Small Cell Lung Cancer

Background

Concurrent chemoradiotherapy is the standard of care for inoperable stage III non-small cell lung cancer (NSCLC) for patients who can tolerate it. We explored if adding erlotinib would increase the effectiveness of chemoradiotherapy without increasing toxicity in a single-arm prospective phase II trial.

Methods

Forty-eight patients with previously untreated NSCLC received intensity-modulated radiation therapy (63 Gy/35 fractions) on Monday–Friday, with chemotherapy (paclitaxel 45 mg/m², carboplatin AUC=2) on Mondays, for 7 weeks. All patients also received the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor erlotinib (150 mg orally 1/day) on Tuesday–Sunday for 7 weeks followed by consolidation paclitaxel–carboplatin. The primary endpoint was time to progression; secondary endpoints were overall survival (OS), toxicity, response, and disease control and whether any endpoint differed by EGFR mutation status.

Results

Of 46 patients evaluable for response, 40 were former or never-smokers and 41 were evaluable for EGFR mutations (37 wild-type [wt] and 4 [mutated; all adenocarcinoma]). Median time to progression was 14.0 months and did not differ by EGFR status. Toxicity was acceptable (no grade 5, one grade 4, eleven grade 3). Twelve patients (26%) had complete responses (10 wt, 2 mutated), 27 (59%) partial (21 wt, 2 mutated, 4 unknown), and 7 (15%) none (6 wt, 2 mutated, 1 unknown) (P=0.610). At 37.0 months’ follow-up (range 3.6–76.5 months) for all patients, median OS time was 36.5 months and 1-, 2-, and 5-year OS rates were 82.6%, 67.4%, and 35.9%; none differed by mutation status. Twelve patients had no progression and 34 had local and/or distant failure. Eleven of 27 distant failures were in the brain (7 wt, 3 mutated, 1 unknown).

Conclusions

Toxicity and OS were promising, but time to progression did not meet expectations. The prevalence of distant failures underscores the need for effective systemic therapy.

Radiation pneumonitis in patients with non--small-cell lung cancer treated with erlotinib concurrent with thoracic radiotherapy

INTRODUCTION

The aim of this study was to investigate the incidence of radiation pneumonitis in patients with non-small-cell lung cancer treated with concurrent thoracic radiotherapy and erlotinib.

METHODS

Patients with inoperable stages IIIA to IV non-small-cell lung cancer who were treated with concurrent thoracic radiotherapy and erlotinib were analyzed. The incidence of radiation pneumonitis was evaluated using the Common Toxicity Criteria (CTC) 3.0 Grading System. The development of grade 2 or higher radiation pneumonitis was the study end point.

RESULTS

Among the 24 patients analyzed, there were nine developed radiation pneumonitis of grade 2 or higher (37.5%), including four cases of grade 2 radiation pneumonitis (16.7%), two of grade 3 radiation pneumonitis (8.3%), and three of grade 5 radiation pneumonitis (12.5%). Three patients developed fatal pneumonia and died of bilateral lung radiation pneumonitis.

CONCLUSIONS

Radiation pneumonitis should be considered in patients treated with concurrent thoracic radiotherapy and erlotinib.

Ossification and increased bone mineral density with zoledronic acid in a patient with lung adenocarcinoma: A case report

Cases of ossification and increased bone mineral density (BMD) at sites of bone metastasis following zoledronic acid (ZA) treatment have not been reported. The current study presents the case of a 65-year-old patient with lung adenocarcinoma and bone metastases in the lumbar vertebrae and femurs. Ossification and an increase in BMD at the metastatic sites was achieved following treatment with ZA and irradiation of the bone metastatic sites. The patient was able to maintain a normal lifestyle for over two years, despite the bone metastases. Therefore, as treatment with ZA was demonstrated to improve patient quality of life, physicians should consider this treatment strategy, particularly for the treatment of metastasis in weight-bearing bones.

Helical tomotherapy for cancer treatment: a rapid health technology assessment

OBJECTIVES

Helical tomotherapy (HT) can be applied to treat complex malignant cancer with high-precise radiotherapy, and it can reduce the damage to normal tissues and improve treatment effects. But the procurement of HT must be approved by relevant departments of administration affairs. This study, appointed by the National Health and Family Planning Commission of China and undertook by the National Health Development Research Center and the Chinese Evidence-Based Medicine Centre, was aimed to rapidly assess the effectiveness, safety, costs, and applicability of HT, so as to provide currently available best evidence for decision-makers of health policies.

METHODS

We electronically searched databases including PubMed, EMbase, The Cochrane Library, CNKI, WanFang Data, VIP, CBM, and other professional websites. Two reviewer independently screened literature according to the inclusion and exclusion criteria, extracted data, assessed quality, and then performed descriptive analysis.

RESULTS

(i) We finally included 150 studies, encompassing 5 HTAs, 18 CCTs, and 127 observational studies. (ii) The included HTAs were published during 2006-2009, providing fairly less evidence of low quality and the results of 145 primary studies showed that: HT had been used mainly in the treatments of 14 kinds of cancer, with low total toxicity and high survival rates. Although the quality of the included studies was poor, there was much evidence about prostate cancer, head and neck cancer, nasopharynx cancer, cervical cancer, lung cancer and liver cancer, with enough sample and fairly reliable results in HT efficacy and safety. And (iii) a total of 56 clinical trials were registered in Clinicaltrials.gov, most of which were registered by the occident. Among them, 9 were completed but the results had not been published yet.

CONCLUSIONS

The evidence of this study showed that, HT is safe and effective in clinic. But the abovementioned conclusion needs to be verified by conducting more high-quality studies with long-term follow-up. The costs of HT in procurement, maintenance, and application are high; and the skills, training, and qualification of operators are required. We suggest that the procurement of HT should be reduced; it should be allocated rationally and effectively used after comprehensive assessment in China's cancer epidemiology characteristics, health resource allocation, disease burden, medical service level, etc.; and also high-quality studies with long-term follow-up should be financially supported on the basis of establishing projects, so as to provide local evidence and consistently guide and improve scientific decision-making.

The reverse effect of X-ray irradiation on acquired gefitinib resistance in non-small cell lung cancer cell line NCI-H1975 in vitro

The clinical efficacy of gefitinib in the treatment of non-small cell lung cancer (NSCLC) with mutations in exon 18, 19 or 21 of epidermal growth factor receptor (EGFR) is limited by the acquired resistance to the drug. To explore whether X-ray irradiation could reverse the acquired gefitinib resistance in NSCLC cell in vitro. We chose a human NSCLC cell line NCI-H1975 to establish acquired gefitinib-resistant cell line named as NCI-H1975/GR. NCI-H1975/GR was irradiated with X-ray and then named as NCI-H1975/GR/XR. In the three cell lines, subsequently cell growth curves and cell population doubling time were calculated by cell proliferation assay, the changes of cell viability were evaluated by trypan blue dye exclusion method and MTT assay, the cell cycle distribution and apoptosis were investigated by flow cytometry, the expressions of E-cadherin and vimentin used to indicate epithelial-mesenchymal transition (EMT) were determined by western blot analysis, the protein expressions in EGFR/KRAS/BRAF transduction pathway were detected by immunocytochemistry, and the mutations of EGFR, KRAS and BRAF were detected by high resolution melting analysis and direct sequencing. We found that the X-ray irradiation enhanced the growth inhibitory effects of gefitinib on the acquired gefitinib-resistant cell line. Of NCI-H1975/GR/XR following gefitinib treatment, the IC50 decreased significantly, the cell proportion of phase G0/G1 was slightly higher, and the apoptosis cell proportion was significantly higher than those of NCI-H1975/GR. In addition, the reversal of EMT being present in NCI-H1975/GR cells was likely appearing in NCI-H1975/GR/XR cells. These results indicated that the acquired gefitinib resistance could be reversed by X-ray irradiation in NSCLC cell line NCI-H1975 harboring both the L858R and T790M mutation in vitro.

Misjudgement of gefitinib efficacy in patients with central non-small-cell lung cancer due to obstructive atelectasis caused by stereotactic radiotherapy

Stereotactic body radiation therapy (SBRT) has been reported to be safe and effective for the treatment of central lung cancer, with mostly tolerable early complications. In this study, we report the development of severe obstructive atelectasis as a late complication in two patients with central lung cancer who received SBRT. This obstructive atelectasis interrupted the evaluation of efficacy of the subsequent gefitinib treatment for non-small-cell lung cancer (NSCLC). The two patients received a total dose of 40 Gy encompassing the planning target volume in 10 fractions (5 fractions/week) at 4 Gy per fraction at the central lesions. Obstructive atelectasis occurred when the patients received subsequent gefitinib treatment. Follow-up reviews or positron emission tomography-computed tomography examination of the two patients confirmed that obstructive atelectasis was actually caused by radiotherapy rather than disease progression. Misjudgement of the cause of ostructive atelectasis in one of the cases resulted in premature termination of gefitinib. Therefore, it is crucial to accurately determine the cause of late complications in NSCLC patients receiving sequential SBRT and gefitinib.

Novel therapeutic strategies for patients with NSCLC that do not respond to treatment with EGFR inhibitors

INTRODUCTION

Treatment with epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) yields tumour responses in non-small cell lung cancer (NSCLC) patients harbouring activating EGFR mutations. However, even in long-lasting responses, resistance to EGFR TKIs invariably occurs.

AREAS COVERED

This review examines resistance mechanisms to EGFR TKI treatment, which mainly arise from secondary EGFR mutations. Other resistance-inducing processes include mesenchymal-epithelial transition factor (MET) amplification, epithelial-mesenchymal transformation, phenotypic change from NSCLC to small-cell lung carcinoma, and modifications in parallel signalling pathways. Current therapeutic strategies to overcome these EGFR TKI resistance mechanisms focus on the inhibition or blocking of multiple members of the ErbB family. Several molecules which target multiple ErbB receptors are being investigated in NSCLC and other indications including afatinib, an ErbB Family Blocker, as well as dacomitinib and lapatinib. Novel, non-quinazoline, EGFR inhibitors, that also target EGFR activating and resistance (T790M) mutations, are currently under clinical development. Other therapeutic strategies include inhibition of parallel and downstream pathways, using agents which target heat shock protein (HSP)90 or poly (ADP-ribose) polymerase in addition to mammalian target of rapamycin (mTOR), monoclonal antibodies against the insulin-like growth factor-1 receptor, and fulvestrant-mediated oestrogen receptor regulation.

CONCLUSION

Improved understanding of mechanisms underlying resistance to EGFR TKIs emphasises the importance of a genotype-guided approach to therapy. Elucidation of resistance mechanisms is indeed crucial to target innovative therapeutic approaches and to improve the efficacy of anticancer regimes in NSCLC.

Progress of clinical research on targeted therapy combined with thoracic radiotherapy for non-small-cell lung cancer

The combination of radiotherapy and targeted therapy is an important approach in the application of targeted therapy in clinical practice, and represents an important opportunity for the development of radiotherapy itself. Numerous agents, including epidermal growth factor receptor, monoclonal antibodies, tyrosine kinase inhibitors, and antiangiogenic therapies, have been used for targeted therapy. A number of studies of radiotherapy combined with targeted therapy in non-small-cell lung carcinoma have been completed or are ongoing. This paper briefly summarizes the drugs involved and the important related clinical research, and indicates that considerable progress has been made with the joint efforts of the two disciplines. Many issues, including drug selection, identification of populations most likely to benefit, timing of administration of medication, and side effects of treatment require further investigation. However, further fundamental research and accumulation of clinical data will provide a more comprehensive understanding of these therapies. Targeted therapy in combination with radiotherapy has a bright future.

Preliminary analysis of the risk factors for radiation pneumonitis in patients with non-small-cell lung cancer treated with concurrent erlotinib and thoracic radiotherapy

Purpose

The aim of this study was to investigate radiation pneumonitis and its associated risk factors in patients with non-small-cell lung cancer treated with concurrent erlotinib and thoracic radiotherapy.

Materials and methods

We conducted an analysis of patients with nonoperable stage IIIA–IV non-small-cell lung cancer who were treated with concurrent thoracic radiotherapy and erlotinib (ClinicalTrials.gov identifier: NCT00973310). The Common Terminology Criteria for Adverse Events version 3.0 grading system was applied to evaluate the incidence of radiation pneumonitis. The lung dosimetric parameters were recorded in accordance with the treatment plan, and the study endpoint was radiation pneumonitis at grade 2 or more.

Results

Among the 24 selected clinical cases, nine were identified with radiation pneumonitis of grade 2 or above (37.5%). This included four cases with grade 2 (16.7%), two cases with grade 3 (8.3%), and three cases with grade 5 (12.5%). The results showed that the planning target volume was a significant factor affecting the incidence of radiation pneumonitis. All lung dosimetric parameters exhibited statistically significant differences between patients with pneumonitis and patients without pneumonitis. The receiver operating characteristic (ROC) curve analysis showed that all lung dosimetric parameters were useful in predicting the incidence of radiation pneumonitis. In addition, the threshold values of V5, V10, V15, V20, V30, and mean lung dose were >44%, >29%, >27%, >22%, >17% and >1,027 cGy, respectively.

Conclusion

Special attention should be paid to the adverse effects of radiation pneumonitis in concurrent thoracic radiotherapy and erlotinib treatment. Lung dosimetric parameters are important predictive factors in radiation pneumonitis.

[Clinical developments for the EGFR-TKI combined with radiotherapy in advanced non-small cell lung cancer]

Lung cancer is one of the most common malignant tumor in the world, severely threatening human life. Recently, targeted therapy such as the epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) made huge progress in treatment of lung cancer. EGFR-TKIs, with its high selectivity and low toxicity, is the first choice for EGFR-mutated patients in stage IV non-small cell lung cancer (NSCLC). However, secondary drug resistance becomes a clinical problem to be urgently resolved. In recent years, a series of preclinical studies showed that EGFR-TKI can enhance the antitumor activity of ionizing radiation. Therefore, EGFR-TKI combined with radiation is extremely promising therapy pattern for advanced NSCLC. This review will discuss the research status in EGFR-TKI and radiotherapy for advanced NSCLC.

Molecular Targeted Drugs and Biomarkers in NSCLC, the Evolving Role of Individualized Therapy

Lung cancer first line treatment has been directed from the non-specific cytotoxic doublet chemotherapy to the molecular targeted. The major limitation of the targeted therapies still remains the small number of patients positive to gene mutations. Furthermore, the differentiation between second line and maintenance therapy has not been fully clarified and differs in the clinical practice between cancer centers. The authors present a segregation between maintenance treatment and second line and present a possible definition for the term “maintenance” treatment. In addition, cancer cell evolution induces mutations and therefore either targeted therapies or non-specific chemotherapy drugs in many patients become ineffective. In the present work pathways such as epidermal growth factor, anaplastic lymphoma kinase, met proto-oncogene and PI3K are extensively presented and correlated with current chemotherapy treatment. Future, perspectives for targeted treatment are presented based on the current publications and ongoing clinical trials.

Design and conduct of early-phase radiotherapy trials with targeted therapeutics: lessons from the PRAVO experience

New strategies to facilitate the improvement of physical and integrated biological optimization of high-precision treatment protocols are an important priority for modern radiation oncology. From a clinical perspective, as knowledge accumulates from molecular radiobiology, there is a complex and exciting opportunity to investigate novel approaches to rational patient treatment stratification based on actionable tumor targets, together with the appropriate design of next-generation early-phase radiotherapy trials utilizing targeted therapeutics, to formally evaluate relevant clinical and biomarker endpoints. A unique aspect in the development pathway of systemic agents with presumed radiosensitizing activity will also be the need for special attention on patient eligibility and the rigorous definition of radiation dose-volume relationships and potential dose-limiting toxicities. Based on recent experience from systematically investigating histone deacetylase inhibitors as radiosensitizing agents, from initial studies in preclinical tumor models through the conduct of a phase I clinical study to evaluate tumor activity of the targeted agent as well as patient safety and tumor response to the combined treatment modality, this communication will summarize principles relating to early clinical evaluation of combining radiotherapy and targeted therapeutics.

[Epidermal growth factor receptor mutations and radiotherapy in non-small cell lung cancer]

Radiotherapy plays a pivotal role in the treatment for lung cancer. Epidermal growth factor receptor (EGFR) mutation in non-small cell lung cancer (NSCLC) which predicts tyrosine kinase inhibitor (TKI) treatment response may also has effect on radiation response. NSCLC harboring kinase-domain mutations in EGFR exhibits enhanced radio-sensitivity due to dramatically diminished capacity to resolve radiation-induced DSBs (DNA double-strand breaks) associating with the inefficiency of EGFR nuclear translocation. Recently, several preliminary clinical studies show certain efficacy of concurrent EGFR tyrosine kinase inhibitors and radiotherapy. However its further response in EGFR-mutated NSCLC is unclear. The correlation between EGFR mutation genotype and the radiotherapy response and clinical outcome is worthy of further study.