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

Accelerated Hypofractionated Chemoradiation Followed by Stereotactic Ablative Radiotherapy Boost for Locally Advanced, Unresectable Non-Small Cell Lung Cancer: A Nonrandomized Controlled Trial

Importance

Intrathoracic progression remains the predominant pattern of failure in patients treated with concurrent chemoradiation followed by a consolidation immune checkpoint inhibitor for locally advanced, unresectable non-small cell lung cancer (NSCLC).

Objective

To determine the maximum tolerated dose (MTD) and use of hypofractionated concurrent chemoradiation with an adaptive stereotactic ablative radiotherapy (SABR) boost.

Design, Setting, and Participants

This was an early-phase, single-institution, radiation dose-escalation nonrandomized controlled trial with concurrent chemotherapy among patients with clinical stage II (inoperable/patient refusal of surgery) or III NSCLC (American Joint Committee on Cancer Staging Manual, seventh edition). Patients were enrolled and treated from May 2011 to May 2018, with a median patient follow-up of 18.2 months. Patients advanced to a higher SABR boost dose if dose-limiting toxic effects (any grade 3 or higher pulmonary, gastrointestinal, or cardiac toxic effects, or any nonhematologic grade 4 or higher toxic effects) occurred in fewer than 33% of the boost cohort within 90 days of follow-up. The current analyses were conducted from January to September 2023.

Intervention

All patients first received 4 Gy × 10 fractions followed by an adaptive SABR boost to residual metabolically active disease, consisting of an additional 25 Gy (low, 5 Gy × 5 fractions), 30 Gy (intermediate, 6 Gy × 5 fractions), or 35 Gy (high, 7 Gy × 5 fractions) with concurrent weekly carboplatin/paclitaxel.

Main Outcome and Measure

The primary outcome was to determine the MTD.

Results

Data from 28 patients (median [range] age, 70 [51-88] years; 16 [57%] male; 24 [86%] with stage III disease) enrolled across the low- (n = 10), intermediate- (n = 9), and high- (n = 9) dose cohorts were evaluated. The protocol-specified MTD was not exceeded. The incidences of nonhematologic acute and late (>90 days) grade 3 or higher toxic effects were 11% and 7%, respectively. No grade 3 toxic effects were observed in the intermediate-dose boost cohort. Two deaths occurred in the high-dose cohort. Two-year local control was 74.1%, 85.7%, and 100.0% for the low-, intermediate-, and high-dose cohorts, respectively. Two-year overall survival was 30.0%, 76.2%, and 55.6% for the low-, intermediate-, and high-dose cohorts, respectively.

Conclusions and Relevance

This early-phase, dose-escalation nonrandomized controlled trial showed that concurrent chemoradiation with an adaptive SABR boost to 70 Gy in 15 fractions with concurrent chemotherapy is a safe and effective regimen for patients with locally advanced, unresectable NSCLC.

Trial Registration

ClinicalTrials.gov Identifier: NCT01345851.

Randomized, Multicenter, Phase 3 Study of Accelerated Fraction Radiation Therapy With Concomitant Boost to the Gross Tumor Volume Compared With Conventional Fractionation in Concurrent Chemoradiation in Patients With Unresectable Stage III Non-Small Cell Lung Cancer: The Korean Radiation Oncology Group 09-03 Trial

PURPOSE

We designed the Korean Radiation Oncology Group 09-03 phase III clinical trial to compare accelerated hypofractionated radiation therapy (RT) using a concomitant boost to the gross tumor volume (GTV) with conventionally fractionated 60-Gy RT in patients with stage III unresectable non-small cell lung cancer (NSCLC).

METHODS AND MATERIALS

A conventionally fractionated RT group (arm 1; 124 patients) received a 2-Gy daily dose to a total cumulative dose of 44 Gy to the planning target volume (PTV) in 22 fractions and 60 Gy to the GTV in 30 fractions over 6 weeks. A hypofractionated RT group (arm 2; 142 patients) received a 1.8-Gy daily dose to the PTV with a synchronous boost of 0.6 Gy to the GTV, for total cumulative doses of 45 Gy to the PTV and 60 Gy to the GTV in 25 fractions over 5 weeks. All patients received concurrent weekly chemotherapy consisting of paclitaxel and cisplatin.

RESULTS

The objective response rate of all patients was 86.5% (arm 1, 84.6%; arm 2, 88.1%; P = .612). The median overall survival was 26 months (arm 1, 26 months; arm 2, 27 months; P = .508). The median progression-free survival was 11 months (arm 1, 10 months; arm 2, 13 months; P = .295). The local tumor control rates at 2 and 5 years were 58.3% and 50.7%, respectively (arm 1, 62.4% and 51.0%, respectively; arm 2, 54.0% and 48.6%, respectively; P = .615). There were no significant between-group differences in the cumulative incidence of grade ≥3 radiation pneumonitis (P = .134) or radiation esophagitis (P = .539).

CONCLUSIONS

This clinical trial did not confirm the superiority of accelerated 2.4-Gy hypofractionated RT compared with conventional 2-Gy fractionation in patients with unresectable stage III NSCLC undergoing concurrent chemoradiation therapy.

Excessive esophageal toxicity in patients with locally advanced non-small cell lung cancer treated with concurrent hypofractionated chemoradiotherapy and 3-weekly platinum doublet chemotherapy

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Concurrent full dose chemoradiotherapy (24x2.75 Gy) is toxic in multiple N2 disease.

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Toxicity after platinum doublet chemoradiation (24x2.75 Gy) is mainly esophageal.

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Fatal toxicity may be increased in patients with bulky centrally located tumors.

Introduction

Concurrent chemoradiation followed by immunotherapy is the standard of care for patients with stage III non-small cell lung cancer (NSCLC). Prior to the introduction of adjuvant immunotherapy, we treated patients with stage III NSCLC with concurrent platinum doublet chemotherapy and 66 Gy in 24 fractions. We determined the toxicity of this treatment.

Methods

A retrospective observational study was performed in a cohort of patients with stage III NSCLC, <70 years old, and WHO performance score 0–1. Patients were treated with concurrent platinum doublet chemotherapy and 66 Gy in 24 fractions. All patients were staged with a PET-scan and brain MRI-scan. Toxicity was scored using the common criteria for adverse events (CTCAE v4.03).

Results

Between 2012 and 2017, 41 patients were treated with mildly hypofractionated radiotherapy and platinum doublet chemotherapy. The median follow-up was 4.7 years. The median age was 57 and 58% of patients were male. The majority of patients had stage IIIB disease (68%). The median total Gross Tumor Volume (GTV) was 104 cc (range: 15–367 cc). The median lymph node GTV was 59 cc (10–341 cc). Five patients died: four due to an esophagus perforation or fistula, and one due to pulmonary bleeding. Grade ≥ 3 esophageal toxicity occurred in 16 patients. Five patients had late grade ≥ 3 esophageal toxicity (12%). The median overall survival was 19 months.

Conclusion

Toxicity was unexpectedly high in patients with stage III NSCLC (WHO 0–1) after concurrent platinum doublet chemotherapy and 66 Gy in 24 fractions.

Chemoradiation with Hypofractionated Proton Therapy in Stage II-III Non-Small Cell Lung Cancer: A YYY Phase 1/2 Trial

INTRODUCTION

Hypofractionated radiotherapy has been safely implemented into the treatment of early-stage non-small cell lung cancer (NSCLC), but not locally advanced (LA-) NSCLC due to prohibitive toxicities with photon therapy. Proton therapy, however, may allow for safe delivery of hypofractionated radiotherapy. We sought to determine whether hypofractionated proton therapy with concurrent chemotherapy improves overall survival.

METHODS & MATERIALS

The YYY conducted a phase 1/2 single-arm nonrandomized prospective multicenter trial from 2013 through 2018. Thirty-two patients were consented; 28 were eligible for on-study treatment. Patients had AJCCv7 stage II or III unresectable NSCLC and received hypofractionated proton therapy at 2.5-4 Gy per fraction to a total 60 Gy with concurrent platin-based doublet chemotherapy. The primary outcome was 1-year overall survival comparable to that reported for RTOG 9410 of 62%.

RESULTS

The trial closed early due to slow accrual, in part, from a competing trial, NRG 1308. Median patient age was 70 (range, 50-86) years. Patients were predominantly male (N=20), white (N=23), and prior smokers (N=27). Most had stage III NSCLC (N=22), 50% of whom had adenocarcinoma. After a median follow-up of 31 months, the 1- and 3-year overall survival rates were 89% and 49%, and progression-free survival rates were 58% and 32%, respectively. No acute grade 3 or higher esophagitis occurred. Only 14% developed a grade 3 or higher radiation-related pulmonary toxicity.

CONCLUSION

Hypofractionated proton therapy delivered at 2.5-3.53 Gy per fraction to a total 60 Gy with concurrent chemotherapy provides promising survival and additional examination through larger studies may be warranted.

Dose-escalation by hypofractionated simultaneous integrated boost IMRT in unresectable stage III non-small-cell lung cancer

Background

To explore the maximum tolerated dose (MTD) and evaluate the safety of dose escalation using hypofractionated simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT) concurrent with chemotherapy for unresectable stage III non-small cell lung cancer (NSCLC).

Methods

Four escalating radiation dose levels were used. This study included 25 patients with previously untreated NSCLC who received six concurrent weekly chemotherapy cycles comprising cisplatin and docetaxel. Dose-limiting toxicity (DLT) was defined as any acute toxicity that interrupted radiotherapy for more than 1 week. MTD was defined as the highest dose level that didn’t induce DLT or grade 5 toxicity in two patients.

Results

All 25 patients received the prescribed escalating radiation dose from the start dose up to LEVEL 4. Two patients experienced DLT at dose LEVEL 4. One patient died because of upper gastrointestinal hemorrhage within 6 months after radiotherapy, whereas another patient among the additional five patients died because of grade 5 radiation pneumonitis within 2 months after radiotherapy. Dose LEVEL 3 was defined as MTD. The 1- and 2-year local controls were 82.8 and 67.8%, respectively. The median progression-free survival was 15.4 months, whereas the median overall survival was 27.3 months.

Conclusions

Dose escalation was safely achieved up to LEVEL 3 [the planning gross target volume (PTVG) 60.5 Gy/22 Fx, 2.75 Gy/Fx; the planning clinical target volume (PTVC) 49.5 Gy/22 Fx] using SIB-IMRT concurrently with chemotherapy for unresectable stage III NSCLC, and the acute toxicities were generally well tolerated. Further prospective studies on long-term outcomes and late toxicities are warranted.

Trial registration

Retrospective registration, ChiCTR1900027290(08/11/2019).

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-09099-3.

Phase I Study of Accelerated Hypofractionated Proton Therapy and Chemotherapy for Locally Advanced Non-Small Cell Lung Cancer

PURPOSE

To evaluate the maximum tolerated dose (MTD) of hypofractionated proton beam radiation therapy (PBT) with concurrent weekly carboplatin/paclitaxel in patients with stage II-III non-small cell lung cancer (NSCLC).

MATERIALS/METHODS

A phase I trial was designed using the Time to Event-Continuous Reassessment Method (TITE-CRM). MTD was defined as the dose associated with a 20% probability of CTCAE protocol-specified serious adverse events (SAEs). Starting dose was 3.5 Gy/fx for 15 fractions with 2 potential escalation and de-escalation levels in 0.25 Gy/fx increments. Chemotherapy was weekly concurrent carboplatin/paclitaxel with 2 cycles of optional consolidation carboplatin/paclitaxel.

RESULTS

From 5/2015-9/2016, 23 patients enrolled at a single institution. Of 20 evaluable, median age was 66.5 years (range, 54-89) and 12 (60%) were male. Fourteen had squamous cell (70%), and 15 (75%) were stage IIIA. Nineteen (95%) completed all 3 cycles of concurrent chemotherapy, and 16 (80%) received at least one cycle of consolidation chemotherapy. Within the 6-month TITE-CRM assessment window, no SAEs were reported, and most patients were treated at the highest dose-level. Dose-level assignment was 52.5 Gy (n=2), 56.25 Gy (n=4), and 60 Gy (n=14). The posterior probability of dose limiting toxicity (DLT) for 60 Gy was 5.3% (95% CI, 1-18.1%).  Acute, non-serious AEs included grade 2 esophagitis in 7 patients (35%) and grade 2 pneumonitis in 1 patient (5%). At a median follow-up of 20.3 months for all and 44.9 months for living patients, there were no grade 4 or 5 AEs, though there were three (21% at 24 months) SAEs outside of the dose-escalation window. The 2-year overall survival, local, regional, and distant control rates were 48%, 84%, 77%, and 79%, respectively.

CONCLUSIONS

Hypofractionated PBT and chemotherapy up to 60 Gy in 15 fractions is acutely well tolerated, with high rates of locoregional control and overall survival, though late SAEs were noted.

Outcomes of Image-Guided Moderately Hypofractionated Radiotherapy for Stage III Non-Small-Cell Lung Cancer

Objective

To evaluate the efficacy and toxicity of hypofractionated radiotherapy (hypo-RT) for stage III non-small-cell lung cancer (NSCLC) in the Chinese population.

Methods

Eighty-six stage III NSCLC patients who received hypo-RT (60 Gy/20 fractions, BED = 78.00 Gy: 73 patients; 62.5 Gy/25 fractions, BED = 78.13 Gy: 13 patients) were recruited. Fifty-seven patients who received conventional radiotherapy (60 Gy/30 fractions, BED = 72.00 Gy) during the same period were enrolled as the control group. All hypo-RT treatments were conducted using image-guided technology. The efficacy and toxicity of the treatment were compared between the two groups.

Results

The median duration of follow-up was 23.0 months (range: 4.0–82.0 months). Univariate and multivariate analyses of all 143 stage III NSCLC patients revealed that hypo-RT was an independent factor for progression-free survival (PFS) and overall survival (OS). The median PFS and OS of hypo-RT were significantly higher than in the conventional RT group (PFS: 14.30, 11.00 months, p=0.035; OS: 43.30, 31.50 months, p=0.045). The incidence rates of symptomatic radiation pneumonitis and radiation esophagitis (≥grade 2) were 17.77% and 27.91%, respectively, in the hypo-RT group. Compared to the conventional radiation therapy group (22.81% and 19.30%, respectively), no significant differences were found between the two common side effects (p=0.662 and p=0.241, respectively).

Conclusion

For Chinese stage III NSCLC patients, image-guided hypo-RT offers favorable prognosis, and the treatment toxicity was totally acceptable. This radiation modality deserves further prospective clinical trials.

Dose and fractionation schedules in radiotherapy for non-small cell lung cancer

In the field of radiotherapy (RT), the issues of total dose, fractionation, and overall treatment time for non-small cell lung cancer (NSCLC) have been extensively investigated. There is some evidence to suggest that higher treatment intensity of RT, when given alone or sequentially with chemotherapy (CHT), is associated with improved survival. However, there is no evidence that the outcome is improved by RT at a higher dose and/or higher intensity when it is used concurrently with CHT. Moreover, some reports on the combination of full dose CHT with a higher biological dose of RT warn of the significant risk posed by such intensification. Stereotactic body radiotherapy (SBRT) provides a high rate of local control in the management of early-stage NSCLC through the use of high ablative doses. However, in centrally located tumors the use of SBRT may carry a risk of serious damage to the great vessels, bronchi, and esophagus, owing to the high ablative doses needed for optimal tumor control. There is a similar problem with moderate hypofractionation in radical RT for locally advanced NSCLC, and more evidence needs to be gathered regarding the safety of such schedules, especially when used in combination with CHT. In this article, we review the current evidence and questions related to RT dose/fractionation in NSCLC.

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

INTRODUCTION

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

METHODS AND ANALYSIS

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

ETHICS AND DISSEMINATION

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

TRIAL REGISTRATION NUMBER

NCT03606239.

Accelerated hypofractionated radiotherapy with concurrent full dose chemotherapy for locally advanced non-small cell lung cancer: A phase I/II study

INTRODUCTION

We report the results of toxicity and survival in stage III NSCLC patients treated with concurrent accelerated hypofractionated AHRT-CHT within a prospective study.

METHODS

92 patients received 3D-CRT or IMRT-planned RT: 58.8 Gy /21 fractions (2.8 Gy/fraction, 4 weeks) with 2 cycles of CHT (Cisplatin 80 mg/m² D1 and D22; and Vinorelbine 25 mg/m², D1, D8, D22, and D29) started with D1 of RT. Non-hematological toxicity was evaluated using RTOG-EORTC criteria, every week during treatment, one month after treatment completion, and every three months thereafter.

RESULTS

Two patients did not receive the prescribed RT dose; 22 (24%) received only one CHT cycle. Median follow-up was 21.5 months (range: 1-65) for all patients and 32 months (range: 8-65) for living patients. There were: 13 (14%) cases of grade ≥III acute esophageal toxicity; 3 grade III acute pneumonitis, and 2 grade III late pulmonary toxicities. Two toxic deaths occurred within 3 months after treatment: fatal hemoptysis (1) and complications of esophageal toxicity (1). Five other deaths that occurred within one year after treatment were probably treatment-related: lung abscess (1), fatal hemoptysis (2), death from undetermined cause (2). Median overall survival was 38 months (95%CI:27-49), median progression free survival was 25 months (95%CI:14-36).

CONCLUSIONS

Survival rates are encouraging, but the observed rate of toxic and probably toxic deaths is of potential concern. We proceed with the use of AHRT with concomitant full dose CHT, but patients with large PTV and major vascular abutment are excluded due to potentially increased risk of toxic death.

Hypofractionated Proton Therapy with Concurrent Chemotherapy for Locally Advanced Non-Small Cell Lung Cancer: A Phase 1 Trial from the University of Florida and Proton Collaborative Group

PURPOSE

We report the safety data from the first multicenter phase 1 trial investigating the use of hypofractionated proton therapy with concurrent chemotherapy for patients with stage II or III non-small cell lung cancer.

METHODS AND MATERIALS

From 2013 through 2018, patients with newly diagnosed stage II or III non-small cell lung cancer were enrolled in a multicenter phase 1 clinical trial evaluating concurrent chemotherapy with increasing dose-per-fraction proton therapy. This was a stepwise 5 + 2 dose-intensification protocol with the following dose arms: (1) 2.5 GyRBE per fraction to 60 GyRBE; (2) 3.0 GyRBE per fraction to 60 GyRBE; (3) 3.53 GyRBE per fraction to 60.01 GyRBE; and (4) 4.0 GyRBE per fraction to 60 GyRBE. A dose arm was considered tolerable if no radiation therapy-attributable severe adverse event (SAE) occurred within 90 days of treatment among 5 patients enrolled on the arm or if 1 SAE occurred among 7 patients enrolled. Dose constraints to the heart, brachial plexus, and spinal cord were more conservative at higher doses per fraction.

RESULTS

The study closed early because of slow accrual and competing enrollment in NRG 1308 before accrual was met, with no maximum tolerated dose identified. Eighteen patients were treated, including 5 patients on arms 1 and 2, 7 patients on arm 3, and 1 patient on arm 4. Two SAEs occurred among 7 patients treated at 3.53 GyRBE per fraction; however, per outside expert review, both were attributed to chemotherapy and unrelated to radiation therapy.

CONCLUSIONS

Hypofractionated proton therapy delivered at 2.5 to 3.53 GyRBE per fraction to a dose of 60 GyRBE with concurrent chemotherapy has an acceptable toxicity profile. Further exploration of this regimen is warranted on a phase 2 clinical trial.

Dose-dependent 60Co γ-radiation Effects on Human Endothelial Cell Mechanical Properties

Exposure to ionizing radiation is unavoidable for noncancerous cells during the external radiotherapy process. Increasing the dose delivery fraction times leads to increasing the endothelial cell damage. Vascular abnormalities are commonly associated with the alternation of endothelium biomechanical properties. The goal of the present study was to quantify the elastic and viscoelastic properties of human umbilical vein endothelial cells (HUVECs) using the micropipette aspiration technique in conjunction with a theoretical model while an 8 Gy dose was given in four fractions. Confocal imaging was performed for evaluation of cytoskeletal changes during fractionation ⁶⁰Co radiotherapy. The results indicated an increase in elastic modulus from 29.87 ± 1.04 Pa to 46.69 ± 1.17 Pa while the fractional doses increased from 0 Gy to 8 Gy along with the obvious cytoskeletal changes. Moreover, in the creep behavior of radiated groups, a significant decrease was shown in the time constant and viscoelastic properties. On the other hand, it was observed that the change in the biomechanical properties of the cells while applying a single fraction of 8 Gy was not exactly the same as that in the properties of the radiation-exposed cells while delivering an 8 Gy dose at 2 Gy per fraction. The observed differences in the biomechanical behavior of endothelium provide a quantitative description of radiobiological effects for evaluating the dose-response relationship as a biological dosimetry procedure.

Hypofractionated radiation therapy in the management of locally advanced NSCLC: a narrative review of the literature on behalf of the Italian Association of Radiation Oncology (AIRO)-Lung Working Group

A systematic literature was performed to assess the benefit in terms of effectiveness and feasibility of hypofractionated radiotherapy (HypoRT), with or without chemotherapy (CT), in the treatment of locally advanced non-small cell lung cancer (NSCLC). We have identified all studies, published from 2007 onwards, on patients with locally advanced NSCLC treated with HypoRT with radical intent, with a minimal dose per fraction of 2.4 Gy, with or without concurrent chemotherapy. Twenty-nine studies were identified, for a total of 2614 patients. Patients were divided in the concurrent chemo-radiation therapy group (CT-RT) and radiotherapy alone (RT). In RT group, the delivered dose ranged from 45 to 85.5 Gy, with a dose/fraction from 2.4 to 4 Gy. Actuarial 2-year PFS ranged from 13 to 57.8%, and 1, 2- and 3-year overall survival (OS) ranged from 51.3 to 95%, from 22 to 68.7%, and from 7 to 32%, respectively. Acute Grade ≥ 3 esophagitis occurred in 0-15%, while late esophageal toxicity was 0-16%. Acute pneumonitis occured in 0-44%, whereas late pneumonitis occured in 0-47%, most commonly grade ≤ G3. In CT-RT group, the delivered dose ranged from 52.5 to 75 Gy, with a dose/fraction ranging from 2.4 to 3.5 Gy. Actuarial 2-year PFS ranged from 19 to 57.8%, and OS at 1, 2 and 3 years ranged from 28 to 95%, 38.6 to 68.7%, and 31 to 44%, respectively. Acute Grade 2 and 3 esophagitis occurred in 3-41.7%, while late esophageal toxicity occurred in 0-8.3%. Acute pneumonitis ranged from 0 to 23%, whereas late pneumonitis occured 0-47%. HypoRT seems to be safe in patients with locally advanced NSCLC. The encouraging survival results of several studies analyzed suggest that hypofractionated radiation schemes should be further investigated in the future.

The acute and late toxicity results of a randomized phase II dose-escalation trial in non-small cell lung cancer (PET-boost trial)

BACKGROUND AND PURPOSE

The PET-boost randomized phase II trial (NCT01024829) investigated dose-escalation to the entire primary tumour or redistributed to regions of high pre-treatment FDG-uptake in inoperable non-small cell lung cancer (NSCLC) patients. We present a toxicity analysis of the 107 patients randomized in the study.

MATERIALS AND METHODS

Patients with stage II-III NSCLC were treated with an isotoxic integrated boost of ≥72 Gy in 24 fractions, with/without chemotherapy and strict dose limits. Toxicity was scored until death according to the CTCAEv3.0.

RESULTS

77 (72%) patients were treated with concurrent chemoradiotherapy. Acute and late ≥G3 occurred in 41% and 25%. For concurrent (C) and sequential or radiotherapy alone (S), the most common acute ≥G3 toxicities were: dysphagia in 14.3% (C) and 3.3% (S), dyspnoea in 2.6% (C) and 6.7% (S), pneumonitis in 0% (C) and 6.7% (S), cardiac toxicity in 6.5% (C) and 3.3% (S). Seventeen patients died of which in 13 patients a possible relation to treatment could not be excluded. In 10 of these 13 patients progressive disease was scored. Fatal pulmonary haemorrhages and oesophageal fistulae were observed in 9 patients.

CONCLUSION

Personalized dose-escalation in inoperable NSCLC patients results in higher acute and late toxicity compared to conventional chemoradiotherapy. The toxicity, however, was within the boundaries of the pre-defined stopping rules.

Palliative thoracic radiation therapy for non-small cell lung cancer: 2018 Update of an American Society for Radiation Oncology (ASTRO) Evidence-Based Guideline

PURPOSE

To revise the recommendation on the use of concurrent chemotherapy (CC) with palliative thoracic external beam radiation therapy (EBRT) made in the original 2011 American Society for Radiation Oncology guideline on palliative thoracic radiation for lung cancer.

METHODS AND MATERIALS

Based on a systematic PubMed search showing new evidence for this key question, the task force felt an update was merited. Guideline recommendations were created using a predefined consensus-building methodology supported by American Society for Radiation Oncology-approved tools for grading evidence quality and recommendation strength.

RESULTS

Although few randomized clinical trials address the question of CC combined with palliative thoracic EBRT for non-small cell lung cancer (NSCLC), a strong consensus was reached among the task force on recommendations for incurable stage III and IV NSCLC. For patients with stage III NSCLC deemed unsuitable for curative therapy but who are (1) candidates for chemotherapy, (2) have an Eastern Cooperative Oncology Group PS of 0 to 2, and (3) have a life expectancy of at least 3 months, administration of a platinum-containing chemotherapy doublet concurrently with moderately hypofractionated palliative thoracic radiation therapy is recommended over treatment with either modality alone. For patients with stage IV NSCLC, routine use of concurrent thoracic chemoradiation is not recommended.

CONCLUSIONS

Optimal palliation of patients with incurable NSCLC requires coordinated interdisciplinary care. Recent data establish a rationale for CC with palliative thoracic EBRT for a well-defined subset of patients with incurable stage III NSCLC. For all other patients with incurable NSCLC, data remain insufficient to support this treatment approach.

Prediction of Radiation Esophagitis in Non-Small Cell Lung Cancer Using Clinical Factors, Dosimetric Parameters, and Pretreatment Cytokine Levels

Radiation esophagitis (RE) is a common adverse event associated with radiotherapy for non-small cell lung cancer (NSCLC). While plasma cytokine levels have been correlated with other forms of radiation-induced toxicity, their association with RE has been less well studied. We analyzed data from 126 patients treated on 4 prospective clinical trials. Logistic regression models based on combinations of dosimetric factors [maximum dose to 2 cubic cm (D2cc) and generalized equivalent uniform dose (gEUD)], clinical variables, and pretreatment plasma levels of 30 cytokines were developed. Cross-validated estimates of area under the receiver operating characteristic curve (AUC) and log likelihood were used to assess prediction accuracy. Dose-only models predicted grade 3 RE with AUC values of 0.750 (D2cc) and 0.727 (gEUD). Combining clinical factors with D2cc increased the AUC to 0.779. Incorporating pretreatment cytokine measurements, modeled as direct associations with RE and as potential interactions with the dose-esophagitis association, produced AUC values of 0.758 and 0.773, respectively. D2cc and gEUD correlated with grade 3 RE with odds ratios (ORs) of 1.094/Gy and 1.096/Gy, respectively. Female gender was associated with a higher risk of RE, with ORs of 1.09 and 1.112 in the D2cc and gEUD models, respectively. Older age was associated with decreased risk of RE, with ORs of 0.992/year and 0.991/year in the D2cc and gEUD models, respectively. Combining clinical with dosimetric factors but not pretreatment cytokine levels yielded improved prediction of grade 3 RE compared to prediction by dose alone. Such multifactorial modeling may prove useful in directing radiation treatment planning.

Outcomes and toxicity following high-dose radiation therapy in 15 fractions for non-small cell lung cancer

PURPOSE

Accelerated hypofractionated radiation therapy (AHRT) is increasingly used for select lung cancer patients. We evaluated clinical outcomes and predictors of pulmonary/esophageal toxicity in patients treated with ≥52.5 Gy in 15 fractions.

METHODS AND MATERIALS

We evaluated 229 patients treated with radiation therapy doses ≥52.5 Gy in 15 fractions for non-small cell lung cancer from January 2009 through January 2016. Toxicity was scored using Common Terminology Criteria for Adverse Events, v4.0. Univariate and multivariate logistic regression was used to identify predictors of toxicity. Overall survival, progression-free survival, and local control were estimated using the Kaplan-Meier method. Predictors of clinical outcome were modeled using Cox proportional hazards regression.

RESULTS

Median follow-up was 7 months. Forty-two patients (19%) developed grade ≥2 pneumonitis, and 9 (4%) developed grade ≥3 esophagitis. In multivariate analysis, age >75 years (odds ratio [OR], 2.56; 95% confidence interval [CI], 1.24-5.25; P = .01) and percentage of lung volume receiving doses of >10 Gy higher than 32% were associated with grade ≥2 pneumonitis (OR, 2.79; 95% CI, 1.39-5.79; P = .005). On univariate analysis, esophagus mean dose ≥17 Gy (OR, 10.14; 95% CI, 1.82-189.8; P = .006), gross tumor volume size ≥71 cm³ (P = .002), and planning target volume size ≥409 cm³ (P = .02) were associated with development of grade ≥3 esophagitis. In patients with stage II/III disease (n = 73), median local control was not reached, median overall survival was 14 months, and median progression-free survival was 6 months.

CONCLUSIONS

AHRT in 15 fractions can be safe and effective. Consideration for using AHRT with immunotherapy and sequential chemotherapy for improved out-of-radiation field and distant control is warranted.