Intensity-Modulated Radiation Therapy May Improve Local-Regional Tumor Control for Locally Advanced Non-Small Cell Lung Cancer Compared With Three-Dimensional Conformal Radiation Therapy

Advances in adjuvant therapy for operable N2 non-small cell lung cancer: a narrative review

Non-small cell lung cancer (NSCLC) is still the disease with the highest incidence rate among malignant tumors, in which NSCLC under N2 stage has obvious survival differences among different patients due to its high heterogeneity. For NSCLC under this stage, the current treatment options are: preoperative neoadjuvant therapy, surgical treatment, postoperative adjuvant chemotherapy, postoperative adjuvant radiotherapy (PORT), Postoperative adjuvant targeted therapy and postoperative adjuvant immunotherapy. Whether postoperative adjuvant radiotherapy is routinely administered to patients with pN2 remains controversial in clinical application. Meanwhile, the booming development of adjuvant targeted therapy and adjuvant immunotherapy also provides newer therapeutic options for the prognosis of postoperative pN2 stage NSCLC, and some new markers will guide the adaptive application of immune drugs in the future. This article analyzes the current stage of therapeutic advances in operable stage N2 non-small cell lung cancer, and discusses in detail in this article the therapeutic controversy of postoperative adjuvant radiotherapy in pN2 stage non-small cell lung cancer, so as to explore a more reasonable treatment mode for future patients with stage N2 non-small cell lung cancer.

IMRT in the treatment of locally advanced or inoperable NSCLC in the pre-durvalumab era: clinical outcomes and pattern of relapses, experience from the Oscar Lambret Center

Background

Intensity-modulated conformal radiotherapy (IMRT) has become the technique of choice for the treatment of locally advanced or inoperable non-small cell lung cancer (NSCLC). Nevertheless, this technique presents dosimetric uncertainties, particularly in treating moving targets such as pulmonary neoplasms. Moreover, it theoretically increases the risk of isolated nodal failure (INF) due to reduced incidental irradiation.

Objective

The objective of this study was to evaluate the efficacy and safety of IMRT in patients with inoperable NSCLC and to describe the pattern of relapses.

Methods

Patients with locally advanced NSCLC treated with radiotherapy and chemotherapy between 2015 and 2018 at the Oscar Lambret Center were retrospectively included in the study. Overall and progression-free survival were estimated using the Kaplan-Meier method. The cumulative incidence of the different components of relapse was estimated using the Kalbfleisch and Prentice method. Prognostic factors for relapse/death were investigated using the Cox model. A comparison with literature data was performed using a one-sample log-rank test.

Results

Seventy patients were included, and 65 patients (93%) had stage III disease. All the patients received chemotherapy, most frequently with cisplatin and navelbine. The dose received was 66 Gy administered in 33 fractions. The median follow-up and survival were 49.1 and 39.1 months, respectively. A total of 35 deaths and 43 relapses, including 29 with metastatic components, were reported. The overall survival rates at 1 and 2 years were 80.2% (95% confidence interval 68.3%-88.0%) and 67.2% (95% confidence interval 54.2%-77.3%), respectively. Locoregional relapse was observed in 14 patients, including two INF, one of which was located in the lymph node area adjacent to the clinical target volume. Median relapse-free survival was 15.2 months. No variable was statistically associated with the risk of relapse/death in multivariate analysis. Seven patients (10%) experienced grade 3 or higher toxicity.

Conclusion

The use of IMRT for locally advanced or inoperable NSCLC led to favorable long-term clinical outcomes. The rate of locoregional relapse, particularly isolated lymph node failure, was low and comparable with that of the three-dimensional radiotherapy series, as was the rate of early and late toxicities.

Radiotherapy Fraction in Limited-Stage Small Cell Lung Cancer in the Modern Era: A Systematic Review and Meta-Analysis of 8006 Reconstructed Individual Patient Data

The optimal thoracic radiotherapy (TRT) dose and fractionation for limited-stage small cell lung cancer (LS-SCLC) using modern techniques remain unclear. We conducted systematic review and meta-analyses of the efficacy and safety differences between definitive hypofractionated TRT (HypoTRT), conventional TRT (ConvTRT) and hyperfractionated TRT (HyperTRT), especially in the modern era. Eligible randomized controlled trials (RCTs), real-world cohorts, and single-arm trials published between 1990 and 2021 were identified. Two meta-analyses of overall survival (OS) were conducted: (i) a random-effects meta-analysis based on reconstructed individual-patient data (IPD) of all studies; and (ii) a Bayesian network meta-analysis based on study-level aggregated data (AD) of RCTs. The incidences of severe radiation-related toxicities were compared using the random-effects meta-regression model. Overall, 53 of the 30,031 publications met the inclusion criteria, and a total of 8006 IPD were reconstructed. After adjusting for key treatment variables and stratification by study type, there were no significant differences in the OS rates between the altered fractionation regimens (HypoTRT vs. HyperTRT, aHR [adjusted HR] = 1.05, 95% CI 0.93-1.19; ConvTRT vs. HyperTRT, aHR = 1.00, 95% CI 0·90-1.11; HypoTRT vs. ConvTRT, aHR = 1.05, 95% CI 0.91-1.20). In the modern era, the survival outcomes of all three schedules, while remaining comparable, have improved significantly. Results of the AD-based network meta-analysis were consistent with those of IPD analysis, and HypoTRT was ranked as the best regimen (SUCRA = 81%). There were no significant differences in toxicities between groups when using modern radiation techniques. In the modern era, no significant differences in OS or severe radiation-related toxicities were observed between altered schedules in LS-SCLC. HypoTRT may be associated with moderate and non-significant OS improvements, which should be further confirmed in prospective randomized phase III trials.

Treatment outcomes of patients with stage III non-small cell lung cancer and interstitial lung diseases receiving intensity-modulated radiation therapy: A single-center experience of 85 cases

OBJECTIVES

Whether curative-intent radiotherapy could be safely applied to lung cancer patients with interstitial lung diseases (ILD) remains unclear. We aim to evaluate radiation induced lung toxicities (RILTs) and the efficacy of intensity-modulated radiotherapy (IMRT) in these patients. ILD is characterized by inflammation or fibrosis in the interstitial tissue of the lung.

MATERIALS AND METHODS

Stage III non-small cell lung cancer (NSCLC) and ILD patients treated with curative-intent IMRT between 2010 and 2019 were retrospectively reviewed. Pre-radiation computed tomography (CT) was scored according to a thin-section CT scoring system for idiopathic pulmonary fibrosis.

RESULTS

A total of 85 of 1261 stage III NSCLC patients were found with ILD. Seventeen (20%) of them developed G3+ (greater than or equal to grade 3) RILTs. The incidence abruptly dropped to 11.1%, 3.8%, and 0% for patients with honeycombing score ≤1, V20 <20%, or both, respectively. Multivariate analysis showed that honeycombing score >1 and V20 ≥20% were independently associated with higher risk of G3+ RILTs. The median overall survival (OS) and progression-free survival (PFS) were 14.0 months and 7.4 months in the whole group, whereas 26.5 months and 10.6 months in the low-risk group (patients with honeycombing score <1 and V20 <20%). In the univariate analysis for overall survival, G3+ RILTs were evaluated as risk factors (p = 0.026) and low-risk group as the only protective factor (p = 0.063). In the multivariate analysis, G3+ RILTs were the only independent risk factor for OS.

CONCLUSION

Honeycombing score >1 and V20 ≥20% were associated with high incidence of RILTs. However, patients with low risk might benefit from IMRT with acceptable toxicities and durable OS.

Surgical complications and clinical outcomes after dose-escalated trimodality therapy for non-small cell lung cancer in the era of intensity-modulated radiotherapy

BACKGROUND

Trimodality therapy (TMT) with preoperative chemoradiation followed by surgical resection is used for locally-advanced non-small-cell lung cancer (LA-NSCLC). Traditionally, preoperative radiation doses ≤54 Gy are used due to concerns regarding excess morbidity, but little is known about outcomes and toxicities after TMT with intensity-modulated radiotherapy (IMRT) to higher doses.

METHODS

A retrospective analysis of patients who received planned TMT with IMRT for LA-NSCLC at Brigham and Women's Hospital/Dana-Farber Cancer Institute between 2008 and 2017 was performed. Clinical and treatment characteristics, pathologic response, and surgical toxicity were assessed. Kaplan-Meier method and log-rank test was used for survival outcomes. Cox proportional-hazards regression was used for multivariable analysis.

RESULTS

Forty-six patients received less than definitive doses of <60 Gy and 30 patients received definitive doses ≥60 Gy. Surgical outcomes, pathologic complete response, and postoperative toxicity did not differ significantly between the groups. With median follow-up of 3.6 years (range: 0.4-11.4), three-year locoregional recurrence-free survival (78.0% vs. 68.3%, p = 0.51) and overall survival (OS) (61.0% vs. 69.4%, p = 0.32) was not significantly different between patients receiving <60 Gy and ≥60 Gy, respectively. On multivariable analysis, older age, clinical stage, and length of hospital stay (LOS) >7 days were associated with OS.

CONCLUSIONS

With IMRT, there was no increased rate of surgical complications in patients receiving higher doses of radiation. Survival outcomes or LOS did not differ based on radiation dose, but increased LOS was associated with worse OS. Larger prospective studies are needed to further examine outcomes after IMRT in patients with LA-NSCLC receiving TMT.

Intensity-modulated radiation therapy with concurrent chemotherapy followed by durvalumab for stage III non-small cell lung cancer: A multi-center retrospective study

BACKGROUND AND PURPOSE

Intensity-modulated radiation therapy (IMRT) is increasingly applied in concurrent chemoradiotherapy (CCRT) for locally-advanced non-small cell lung cancer (NSCLC), with improvement of target coverage and better sparing of normal tissue. IMRT tends to have a larger low-dose irradiation volume than 3D conformal radiotherapy, but the incidence of and risk factors for pneumonitis remain unclear, especially following the approval of durvalumab.

MATERIALS AND METHODS

We retrospectively reviewed the records of NSCLC patients treated by CCRT using IMRT at seven Japanese institutions. Primary outcomes were incidence of symptomatic pneumonitis and progression-free survival (PFS). Multivariate logistic regression analysis was used to identify risk factors for ≥grade 2 pneumonitis.

RESULTS

Median follow-up from the start of CCRT was 14.3 months (n = 107 patients; median age 70 years, 29% female). Median lung V5 and V20 was 49.2% and 19.5%, respectively. Durvalumab was administered to 87 patients (81%). Pneumonitis developed in 95 (89%) patients of which 53% had grade 1, 28% grade 2, 6.5% grade 3, and 0.9% grade 4. Durvalumab had been discontinued in 16 patients (18.4%) due to pneumonitis. By multivariate analysis, age ≥70 years, male sex, and V5 ≥58.9% were identified as significantly associated with ≥grade 2 pneumonitis (p = 0.0065, 0.036 and 0.0013 respectively). The median PFS from the start of CCRT was not reached (95% CI, 14.2 months to not reached) in patients receiving durvalumab.

CONCLUSION

CCRT using IMRT followed by durvalumab was generally effective and tolerable; V5 <60% would be recommended to avoid symptomatic pneumonitis.

Long-term outcomes of high-dose (74 GyE) proton beam therapy with concurrent chemotherapy for stage III nonsmall-cell lung cancer

BACKGROUND

To evaluate the long-term outcomes of high-dose (74 GyE) proton beam therapy (PBT) with concurrent chemotherapy for stage III non-small cell lung cancer (NSCLC).

METHODS

Between July 2007 and March 2018, 45 patients with stage III NSCLC were treated with passive-scattering PBT of 74 GyE and concurrent chemotherapy. Among the 45 patients, the median age was 62 years (range 39-79 years) and 32 patients were men. The clinical stages were stage IIIA in 14 patients and stage IIIB in 31 patients. Thirty-six patients received chemotherapy consisting of cisplatin and vinorelbine.

RESULTS

The median follow-up time was 42.1 months (range 6.4-127.0 months) for all patients and 63.5 months (range 9.4-127.0 months) for the 12 survivors. The 3- and 5-year overall survival rates were 63.7% and 38.8%, respectively, and the median overall survival was 49.1 months. Over the follow-up period, disease recurrence was observed in 32 (71%) patients. The 3- and 5-year progression-free survival rates were 22.2% and 17.7%, respectively, with a median progression-free survival of 13.1 months. In-field control improved survival and the in-field control rate was better in patients with T0-3 tumors (p = 0.023) and stage IIIA/IIIB-N3 disease (p = 0.030). Dosimetric parameters of the heart and lung were not associated with survival. No grade 4 or 5 acute or late non-hematologic toxicities were observed.

CONCLUSIONS

Passive-scattering PBT of 74 GyE with chemotherapy showed favorable survival and a low incidence of severe adverse events in patients with stage III NSCLC.

Toxicity after volumetric modulated arc therapy for lung cancer: a monocentric retrospective study

Background

Intensity-modulated radiotherapy (RT) is now widely implemented and has replaced classical three-dimensional (3D)-RT in many tumor sites, as it allows a better target dose conformity and a better sparing of organs a risk (OAR), at the expense, however, of increasing the volume of low dose to normal tissues. Clinical data on toxicities using volumetric modulated arc therapy (VMAT) in lung cancer remain scarce. We aimed to report both acute (APT) and late (LPT) pulmonary and acute (AET) and late (LET) oesophageal toxicities in such setting.

Methods

All patients treated for a primary lung cancer with VMAT +/- chemotherapy (ChT) in our center from 2014 to 2018 were retrospectively included. Usual clinical, treatment and dosimetric features were collected. Univariate analysis was performed using the receiver operative characteristics approach while multivariate analysis (MVA) relied on logistic regression, calculated with Medcalc 14.8.1.

Results

In total, 167 patients were included, with a median age of 66 years (39-88 years). Median radiation dose was 66 Gy (30-66 Gy); 82% patients received concomitant (32.3%), induction (25.7%) or induction followed by concomitant ChT (24%). After a median follow-up of 14.0 months, the G ≥2 APT, AET, LPT and LET rates were 22.2%, 30.0%, 16.8% and 5.4%, respectively with low grade ≥3 toxicity rates (respectively, 3%, 6.6%, 3% and 0%). On MVA, APT was significantly associated with V30 to the homolateral lung, AET with age, LPT with MEVS while no feature remained significantly correlated with LET.

Conclusions

Low rates of pulmonary and esophageal toxicity were observed in our cohort. Larger prospective studies are needed to confirm these results.

Sparing Organs at Risk with Simultaneous Integrated Boost Volumetric Modulated Arc Therapy for Locally Advanced Non-Small Cell Lung Cancer: An Automatic Treatment Planning Study

Background

The technique of simultaneous integrated boost volumetric modulated arc therapy (SIB-VMAT) has been widely used in locally advanced non-small cell lung cancer; however, its dosimetric advantages are seldom reported. This study aimed to quantify dosimetric advantages of SIB-VMAT.

Methods

Forty patients with stage III non-small cell lung cancer in our hospital were retrospectively included. SIB-VMAT and conventional VMAT (C-VMAT) plans were generated for every patient using the automatic treatment planning system. A reduced dose was delivered to PTV in SIB-VAMT plans compared to C-VMAT plans (50.4Gy vs 60Gy). The prescribed dose was 50.4 Gy in 28 fractions to PTV and 59.92 Gy in 28 fractions to PGTV in SIB-VMAT plans, while 60 Gy in 30 fractions to PTV in C-VMAT plans. Dose-volume metrics of PTV, total lung, heart, esophagus and spinal cord were recorded. The quality score was used to evaluate organs at risk (OAR) protection for two type prescription plans.

Results

Conformal coverage of the targets (PGTV/PTV) by 95% of the prescription dose was well achieved in radiation plans. SIB-VMAT plans achieved significantly higher quality score than C-VMAT plans (Mean: 68.15±13.32 vs 49.15±13.35, P<0.001). More plans scored above sixty in SIB-VMAT group compared to C-VMAT group (72.5% vs 20%, P<0.001). Notable reductions in mean dose, V₃₀, V₄₀ and V₅₀ of total lung were observed in SIB-VMAT plans compared to C-VMAT plans, with median decreased proportions of 6.5%, 8.7%, 19.6% and 32.1%, respectively. Statistically significant decrease in heart V₃₀ and V₄₀ was also achieved in SIB-VMAT plans, with median decreased proportions of 26.1% and 38.8%. SIB-VMAT plans achieved significant reductions in the maximum doses to both esophagus and spinal cord. Patients with CTV/(GTV+GTVnd) ≥8.6 showed more notable decrease in total lung V₅₀ (median, 33.6% vs 28.8%, P=0.001) in SIB-VMAT plans compared to those with the ratio being less than 8.6.

Conclusion

SIB-VMAT technique could lead to a substantial sparing of normal organs, including lung, heart, esophagus and cord, mainly through reducing high and inter-median dose exposure. Patients with CTV/(GTV+GTVnd) ≥8.6 might benefit more from SIB-VMAT.

Is clinical target volume necessary?-a failure pattern analysis in patients with locally advanced non-small cell lung cancer treated with concurrent chemoradiotherapy using intensity-modulated radiotherapy technique

Background

Our previous dosimetric study showed that for locally advanced non-small cell lung cancer (LA-NSCLC), radiotherapy with intensity-modulated radiotherapy (IMRT) technique could deliver sufficient dose coverage to subclinical regions and reduce the dose to normal tissues with the omission of clinical target volume (CTV). To further clinically validate this strategy, we conducted the current study to analyze the failure pattern for patients with LA-NSCLC treated with concurrent chemotherapy and CTV-omitted IMRT. We also investigated the effects of target volumes on lymphopenia during radiotherapy to further test the potential benefits of CTV omission in anti-tumor immunotherapy.

Methods

A total of 63 patients with LA-NSCLC treated with CTV-omitted IMRT with concurrent chemotherapy were enrolled in this study. Their planning target volume (PTV) (also PTV-g) was expanded directly from gross tumor volume (GTV). A virtual CTV was expanded from GTV, and the PTV generated from virtual CTV was named planning target volume with CTV expansion (PTV-c). Treatment failures were divided into local, regional, and distant failures, and local–regional recurrences were classified into inside PTV-g (IN-PTV-g), between PTV-g and PTV-c (PTV-g-c), and outside PTV-c (OUT-PTV-c). The relationship between lymphopenia during radiotherapy and the target volumes was also evaluated using Spearman’s correlation analysis.

Results

Among the 60 patients with detailed follow-up data for recurrences, 46 (76.7%) experienced recurrences, with 18 (30.0%) being local recurrence, 5 (8.4%) being regional failure, and 33 (55.0%) being distant failure. For the 21 patients with local–regional recurrences, 16, 6, and 1 were IN-PTV-g, OUT-PTV-c, and PTV-g-c recurrences, respectively. Lymphopenia during radiotherapy was associated with both GTV and PTV, with larger volumes linked to severe lymphopenia.

Conclusions

CTV omission is feasible for LA-NSCLC treated with concurrent chemoradiotherapy and does not compromise failure inside the subclinical region. The radiation volumes were associated with lymphopenia during radiotherapy, with larger volumes related to severe lymphopenia. This finding supports the further exploration of CTV omission for immunotherapy.

Simultaneous integrated boost of intensity-modulated radiation therapy to Stage II-III non-small cell lung cancer with metastatic lymph nodes

Local tumor failure remains a major problem after radiation‐based nonsurgical treatment for unresectable locally advanced nonsmall cell lung cancer (NSCLC）and inoperable stage II NSCLC. The aim of this study was to evaluate the feasibility of simultaneous integrated boost of intensity‐modulated radiation therapy (SIB‐IMRT) to stage II‐III NSCLC with metastatic lymph nodes (ChiCTR 2000029304). Patients were diagnosed by pathology or PET‐CT. PTV was divided into two parts as follows, the PTV of primary tumor (PTVp) and the PTV of metastatic lymph nodes (PTVn). The radiotherapy doses were simultaneously prescripted 78 Gy (BED = 101.48 Gy) for PTVp and 60‐65 Gy (BED = 73.6‐81.25 Gy) for PTVn, 26f/5.2 weeks. Response was scored according to WHO criteria. Radiotherapy toxicity was scored according to RTOG criteria. Hematology and gastrointestinal toxicity were scored according to CTCAE1.0 criteria. A total of 20 patients were enrolled. Seventeen patients were diagnosed by pathology and three patients were diagnosed by PET‐CT. All patients were treated with SIB‐IMRT. The objective response rate (ORR) was 90%, with CR 25%, PR 65%, NC 10%, and PD 0%. Although radiotherapy toxicity was common, there were no grade ≥3, with radiation pneumonitis (10 cases), esophagitis (17 cases), and dermatitis (12 cases). The local control rates at 1, 3, and 5 years were 85%, 75%, and 70%, respectively. The overall survival（OS）and local progression‐free survival (LPFS) rates at 1, 3, and 5 years were 90%, 42.6%, and 35.5% and 84.4%, 35.5%, and 28.4%, respectively. SIB‐IMRT can significantly improve ORR and survival for stage II‐III NSCLC with metastatic lymph nodes, with high safety, and satisfactory efficacy. However, due to the limitation of small sample, these findings are needed to confirm by future trials with a larger sample size.

Current radiotherapy techniques in NSCLC: challenges and potential solutions

Introduction: Radiotherapy is an important therapeutic strategy in the management of non-small cell lung cancer (NSCLC). In recent decades, technological implementations and the introduction of image guided radiotherapy (IGRT) have significantly increased the accuracy and tolerability of radiation therapy.Area covered: In this review, we provide an overview of technological opportunities and future prospects in NSCLC management.Expert opinion: Stereotactic body radiotherapy (SBRT) is now considered the standard approach in patients ineligible for surgery, while in operable cases, it is still under debate. Additionally, in combination with systemic treatment, SBRT is an innovative option for managing oligometastatic patients and features encouraging initial results in clinical outcomes. To date, in inoperable locally advanced NSCLC, the radical dose prescription has not changed (60 Gy in 30 fractions), despite the median overall survival progressively increasing. These results arise from technological improvements in precisely hitting target treatment volumes and organ at risk sparing, which are associated with better treatment qualities. Finally, for the management of NSCLC, proton and carbon ion therapies and the recent development of MR-Linac are new, intriguing technological approaches under investigation.

Efficacy and safety of CT-guided 125I brachytherapy in elderly patients with non-small cell lung cancer

Non-small cell lung cancer (NSCLC) has become the most common cancer type and the leading cause of cancer-associated mortality worldwide. The aim of the present retrospective study was to evaluate the efficacy and safety of computed tomography (CT)-guided ¹²⁵I brachytherapy alone in elderly patients with NSCLC. A total of 26 elderly patients with NSCLC stage I–III who had an inoperable lesion or progressive disease following radio-chemotherapy were treated with CT-guided ¹²⁵I seed implantation for lung lesions and included in the present study. The prescribed dose of ¹²⁵I brachytherapy was 80–140 Gy, and dosimetric verification was performed immediately after the procedure. The response rate (RR) and local control rate (LCR) were analyzed according to the Response Evaluation Criteria in Solid Tumors (version 1.1). Survival was estimated using the Kaplan-Meier method. Safety and complications were also documented. All patients were aged 65–85 years (median age, 77 years) and successfully completed the procedure, and the median follow-up time was 9.4 months (range, 3–31 months). After a 6-month follow-up, for pulmonary lesions, complete response (CR) was achieved in 11 (42.3%) cases, partial response in 9 (34.6%) cases, stable disease in 4 (15.4%) cases and progressive disease in 2 (7.7%) cases. The 6-month RR and LCR were 76.9 (20/26) and 92.3% (24/26), respectively. The mean overall survival (OS) time was 11.7±7.6 months and the 0.5- and 1-year OS rates were 90.1 and 73.3%, respectively. Tumor-related symptoms in patients were significantly alleviated following the procedure. No severe complications occurred during and after the procedure of ¹²⁵I seed implantation. In conclusion, CT-guided ¹²⁵I brachytherapy is a feasible, effective and safe therapy and may be considered as an alternative option to surgery and radiotherapy for elderly patients with NSCLC.

Efficacy and safety of concurrent chemoradiotherapy in ECOG 2 patients with locally advanced non-small-cell lung cancer: a subgroup analysis of a randomized phase III trial

BACKGROUND

There is no consensus on the therapeutic approach to ECOG 2 patients with locally advanced non-small-cell lung cancer (LA-NSCLC), despite the sizable percentage of these patients in clinical practice. This study focused on the efficacy, toxicity and the optimal chemotherapy regimen of CCRT in ECOG 2 patients in a phase III trial.

METHODS

Patients capable of all self-care with bed rest for less than 50% of daytime were classified as ECOG 2 subgroup. A subgroup analysis was performed for ECOG 2 patients recruited in the phase III trial receiving concurrent EP (etoposide + cisplatin)/PC (paclitaxel + carboplatin) chemotherapy with intensity-modulated radiation therapy (IMRT) or three-dimensional conformal external beam radiation therapy (3D-CRT).

RESULTS

A total of 71 ECOG 2 patients were enrolled into the study. Forty-six (64.8%) patients were treated with IMRT technique. The median overall survival (OS) and progression free survival (PFS) for ECOG 2 patients were 16.4 months and 9 months, respectively. No difference was observed in treatment compliance and toxicities between ECOG 2 patients and ECOG 0-1 patients. Within the ECOG 2 group (31 in the EP arm and 40 in the PC arm), median OS and 3-year OS were 15.7 months and 37.5% for the EP arm, and 16.8 months and 7.5% for the PC arm, respectively (p = 0.243). The incidence of grade ≥ 3 radiation pneumonitis was higher in the PC arm (17.5% vs. 0.0%, p = 0.014) with 5 radiation pneumonitis related deaths, while the incidence of grade 3 esophagitis was numerically higher in the EP arm (25.8% vs. 10.0%, p = 0.078).

CONCLUSIONS

CCRT provided ECOG 2 patients promising outcome with acceptable toxicities. EP might be superior to PC in terms of safety profile in the setting of CCRT for ECOG 2 patients. Prospective randomized studies based on IMRT technique are warranted to validate our findings.

TRIAL REGISTRATION

ClinicalTrials.gov registration number: NCT01494558. (Registered 19 December 2011).

Postoperative Radiotherapy for Resected Stage IIIA-N2 Non-small-cell Lung Cancer: A Population-Based Time-Trend Study

INTRODUCTION

The value of postoperative radiotherapy (PORT) for resected stage IIIA-N2 non-small-cell lung cancer (NSCLC) is controversial with few studies focusing on whether PORT always plays a part in clinical practice and generates benefits to patients across different time periods. We investigated this issue using the Surveillance, Epidemiology, and End Results Database (SEER) and assessed the temporal trends spanning 27 years.

METHODS

Within SEER, we selected stage IIIA-N2 NSCLC patients who underwent a lobectomy or pneumonectomy and coded as receiving PORT or never receiving radiotherapy over three time periods: 1988 to 1996, 1997 to 2005, 2006 to 2014. For each period, survival analyses were performed and propensity score matching (PSM) was used in the potentially beneficial subgroup.

RESULTS

45.4% of 5568 eligible patients received PORT. The yearly PORT use rates varied largely from 27.8% to 74.4%. Overall survival (OS) was distinctly improved over the period. The application of PORT had a significant impact on survival only in period 1 and 3. In subgroup analysis, the OS benefit of PORT was significant in each period in patients with 50% or more lymph node ratio (LNR) both before (hazard ratios, and P values of 0.647, P = .002; 0.804, P = .008; 0.721, P < .001 for period 1, 2, 3, respectively) and after PSM (0.642, P = .006; 0.785, P = .004; 0.748, P = .003 for period 1, 2, 3, respectively).

CONCLUSIONS

The benefits of PORT are lasting and stable throughout the years in patients with LNR of 50% or more. This might provide a clue on proper patient selection for PORT application.

Comparison of efficacy and safety between simultaneous integrated boost intensity-modulated radiotherapy and conventional intensity-modulated radiotherapy in locally advanced non-small-cell lung cancer: a retrospective study

Background

Consistent results are lacking as regards the comparative effectiveness of simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) versus conventional intensity-modulated radiotherapy in patients with locally advanced non-small-cell lung cancer (LA-NSCLC). Therefore, we conducted a retrospective analysis to demonstrate the role of SIB-IMRT for patients.

Methods

Patients who had histologically confirmed NSCLC, stage III disease and received thoracic IMRT between 2014 and 2016 were retrospectively reviewed. The survival, toxicities and dose to organs at risk (OAR) were compared among patients irradiated with different techniques. The SIB-IMRT plans were designed to deliver 45–59.4Gy (median: 50.4Gy) to PTV while simultaneously delivering 50-70Gy (median: 59.92Gy) to PGTV. As for conventional IMRT plans, a total dose of 50-70Gy (median: 60Gy) was delivered to PTV.

Results

426 patients with stage III NSCLC were eligible for analysis, including 128 with SIB-IMRT and 298 with conventional IMRT. The SIB-IMRT group had more stage IIIB disease (69.5% vs. 53%, P = 0.002), larger planning treatment volumes (median: 504 ml vs. 402 ml, P<0.001), and a larger planning treatment volume/volume of lung ratio (median, 0.18 vs. 0.12, P<0.001). The median OS of the SIB-IMRT and conventional IMRT groups were 34.5 and 31.7 months, with the 2-year rate of 60.4 and 59%, respectively (P = 0.797). No difference in PFS, LRFS or DMFS was observed between the two techniques. Patients treated with SIB-IMRT got similar lung and esophageal toxicities versus those with conventional IMRT.

Conclusions

SIB-IMRT may be an effective and safe option for patients with locally advanced NSCLC, especially for those with large mass or wide lymph node metastasis.

Impact of modern radiotherapy techniques on survival outcomes for unselected patients with large volume non-small cell lung cancer

OBJECTIVE:

Intensity modulated radiotherapy (IMRT) is used, where necessary, for bulky or complex-shaped, locally advanced, non-small cell lung cancer (NSCLC). We evaluate our real-world experience with radical radiotherapy including concurrent chemoradiation (CCRT), and analyse the impact of IMRT on survival outcomes in patients with larger volume disease.

METHODS:

All patients treated between May 2011 and December 2017 were included. Analyses were conducted for factors affecting survival, including large volume disease that was defined as planning target volume (PTV) > 500 cc.

RESULTS:

In 184 patients with large volume disease, the median overall survival was 19.2 months, compared to 22 months seen with the overall cohort of 251 patients who received radical radiotherapy. PTV and using CCRT were significant predictors for survival. IMRT was used in 93 (50.5%) of 184 patients with large PTV. The patients treated using IMRT had significantly larger disease volume (median PTV = 859 vs 716 cc; p-value = 0.009) and more advanced stage (proportion of Stage IIIB: 56 vs 29%; p-value = 0.003) compared to patients treated with three-dimensional conformal radiotherapy. Yet, the outcomes with IMRT were non-inferior to those treated with 3DCRT. CCRT was used in 103 (56%) patients with large volume disease and resulted in a significantly better median survival of 24.9 months. The proportional benefit from CCRT was also greater than in the overall cohort.

CONCLUSION:

Despite being used for larger volume and more advanced NSCLC, inverse-planned IMRT resulted in non-inferior survival.

ADVANCES IN KNOWLEDGE:

IMRT enables the safe use of curative CCRT for large-volume, locally-advanced NSCLC.

Advanced radiation techniques for locally advanced non-small cell lung cancer: intensity-modulated radiation therapy and proton therapy

Radiation therapy (RT) represents an integral part of a multimodality treatment plan in the definitive, preoperative and postoperative management of non-small cell lung cancer (NSCLC). Technological advances in RT have enabled a shift from two-dimensional radiotherapy to more conformal techniques. Three-dimensional conformal radiotherapy (3DCRT), the current minimum technological standard for treating NSCLC, allows for more accurate delineation of tumor burden by using computed tomography-based treatment planning instead of two-dimensional radiographs. Intensity-modulated RT (IMRT) and proton therapy represent advancements over 3DCRT that aim to improve the conformity of RT and provide the possibility for dose escalation to the tumor by minimizing radiation dose to organs at risk. Both techniques likely confer benefits to certain anatomic subgroups of NSCLC requiring RT. This article reviews pertinent studies evaluating the use of IMRT and proton therapy in locally advanced NSCLC, and outlines challenges, indications for use, and areas for future research.

Increased CYFRA 21-1, CEA and NSE are Prognostic of Poor Outcome for Locally Advanced Squamous Cell Carcinoma in Lung: A Nomogram and Recursive Partitioning Risk Stratification Analysis

OBJECTIVES

This study aimed to: (1) assess the prognostic significance of serum tumor markers in locally advanced squamous cell carcinoma in lung (LA-SCCL); (2) generate a nomogram to predict the overall survival (OS) and (3) identify a prognostic stratification to assist the therapeutic decision-making.

METHODS

LA-SCCL patients receiving definitive radiotherapy and baseline tumor marker measurement were eligible for this retrospective study. Cox proportional hazards regression was used to determine independent factors associated with various survival indexes and a nomogram was created to estimate the 5-year OS probability for individual patient. The identified prognostic factors were recruited into a recursive partitioning analysis (RPA) for OS to stratify patients with distinct outcome.

RESULTS

A total of 224 patients were eligible for analysis. Increased cytokeratin-19 fragment (CYFRA 21-1) was independently associated with inferior OS, progression free survival (PFS) and a borderline decreased local-regional progression free survival (LRPFS). Elevated carcino-embryonic antigen (CEA) served as an unfavorable determinant for OS and increased neuron-specific enolase (NSE) was predictive of poor distant metastasis free survival (DMFS). A nomogram integrating KPS, TNM stage, CEA and CYFRA 21-1 was created, resulting in a c-index of 0.62. RPA identified 4 prognostic classifications, with median OS of 27.6, 19.9, 17.3 and 10.9 months for low, intermediate, high and very-high risk groups, respectively.

CONCLUSIONS

Baseline tumor marker panel including CYFRA 21-1, CEA and NSE can be prognostic of outcome for LA-SCCL receiving definitive radiotherapy. The RPA identified four prognostic subgroups, which could assist personalized therapy and clinical trial design in LA-SCCL.

Application of intensity-modulated radiation therapy in the treatment of nasopharyngeal carcinoma

The objective of the present study was to investigate the application values of the intensity-modulated radiation therapy (IMRT) and the three-dimensional conformal radiation therapy (3D-CRT) in the treatment of nasopharyngeal carcinoma (NPC). A total of 124 patients diagnosed with nasopharyngeal carcinomas were included into the study and randomly divided into the control group and the observation group, with 62 patients in each group. The 3D-CRT combined with postoperative chemotherapy were performed on the control group and the observation group received IMRT combined with postoperative chemotherapy, and then were followed up for a median duration of 25.5 months. Comparison of the survival analysis of the two groups showed no differences between them in terms of the total effective rate and effectiveness (P>0.05), or radiotherapy complications (P>0.05). In addition, no significant differences between the two groups were found in the follow-up local tumor control probability (TCP), regional lymph node control rate, distant metastasis-free rate, tumor-free survival rate, recurrence rate and overall survival rate (P>0.05). Furthermore, there was no difference between the two groups in the overall score of quality of life (P>0.05). The present study concludes that the IMRT and the 3D-CRT have almost the same short-term and long-term clinical effects in the treatment of nasopharyngeal carcinoma and both of them have high effectiveness and safety.

Selective ATP hydrolysis inhibition in F1Fo ATP synthase enhances radiosensitivity in non-small-cell lung cancer cells (A549)

Background

F1Fo-ATP synthase (F1Fo-ATPase) is a reversibly rotary molecular machine whose dual functions of synthesizing or hydrolyzing ATP switch upon the condition of cell physiology. The robust ATP-hydrolyzing activity occurs in ischemia for maintaining the transmembrane proton motive force of mitochondria inner membrane, but the effect of F1Fo-ATPase on X-ray response of non-small-cell lung cancer (NSCLC) cells is unknown.

Methods and Findings

We studied whether ATP hydrolysis affected X-ray radiation induced cell death. NSCLC cells (A549) were pretreated with BTB06584 (BTB), an elective ATP hydrolysis inhibitor, followed by X-ray radiation. Cell viability and clonogenic survival were markedly decreased, clear indications of enhanced radiosensitivity through BTB incubation. Additionally, ATP5α1 was upregulated in parallel with elevated ATP hydrolytic activity after X-ray radiation, showing an increased mitochondrial membrane potential (ΔΨm). ATP hydrolysis inhibition led to collapse of ΔΨm suggesting ATP hydrolytic activity could enhance ΔΨm after X-ray radiation. Furthermore, we also demonstrated that apoptosis was pronounced with the prolonged collapse of ΔΨm due to hydrolysis inhibition by BTB incubation.

Conclusion

Overall, these findings supported that ATP hydrolysis inhibition could enhance the radiosensitivity in NSCLC cells (A549) after X-ray radiation, which was due to the collapse of ΔΨm.