An esophagus-sparing technique to limit radiation esophagitis in locally advanced non-small cell lung cancer treated by simultaneous integrated boost intensity-modulated radiotherapy and concurrent chemotherapy

Toxicities and Deaths From Intercurrent Disease Following Contemporary Postoperative Radiotherapy in Resected Non-Small-Cell Lung Cancer

INTRODUCTION

The role of postoperative radiotherapy (PORT) in patients with resected locally advanced non-small-cell lung cancer (NSCLC) remains controversial due to the radiation techniques used in randomized trials. We conducted a retrospective cohort study evaluating contemporary PORT techniques to evaluate the safety of PORT and risk of death from intercurrent disease .

MATERIALS AND METHODS

We analyzed consecutive patients with NSCLC treated in a single center that underwent PORT for pN2 disease and/or positive margin, with 3-dimensional conformal radiotherapy (3DRT), intensity modulated radiotherapy , or proton RT (PRT), between 2008 and 2019. Clinical details were collected including intercurrent deaths, defined as death without cancer recurrence. Kaplan-Meier and Cox-Proportional Hazards Models were used.

RESULTS

Of 119 patients, 21 (17.6%) received 3DRT, 47 (39.5%) intensity modulated radiotherapy, and 51 (42.9%) PRT. Median follow-up was 40 months (range 8-136) and median RT dose was 5040cGy. Most patients (65.5%) received sequential adjuvant chemoRT; 18.5% received concurrent chemoRT. The rate of grade 3 toxicities was 9.2%. There were 13 (10.9%) deaths from intercurrent diseases, including 6 from second primary cancers and 2 from cardiopulmonary diseases. There were 2 additional deaths from cardiopulmonary disease in patients with cancer progression at time of death. Mean, V5Gy, V30Gy heart doses and mean lung doses were significantly lower with PRT. Three-year OS and disease-free-survival were 70.1% and 49.9%.

CONCLUSION

PORT using contemporary techniques was well tolerated with acceptable toxicity and low rates of intercurrent deaths. Proton therapy significantly reduced heart and lung doses, but radiotherapy modality was not associated with differences in intercurrent disease.

Using inflammatory indexes and clinical parameters to predict radiation esophagitis in patients with small-cell lung cancer undergoing chemoradiotherapy

OBJECTIVE

Radiation esophagitis (RE) is a common adverse effect in small cell lung cancer (SCLC) patients undergoing thoracic radiotherapy. We aim to develop a novel nomogram to predict the acute severe RE (grade≥2) receiving chemoradiation in SCLC patients.

MATERIALS AND METHODS

the risk factors were analyzed by logistic regression, and a nomogram was constructed based on multivariate analysis results. The clinical value of the model was evaluated using the area under the receiver operating curve (ROC) curve (AUC), calibration curves, and decision curve analysis (DCA). The correlations of inflammation indexes were assessed using Spearman correlation analysis.

RESULTS

Eighty-four of 187 patients (44.9%) developed grade ≥2 RE. Univariate analysis indicated that concurrent chemoradiotherapy (CCRT, p < 0.001), chemotherapy cycle (p = 0.097), system inflammation response index (SIRI, p = 0.048), prognostic-nutrition index (PNI, p = 0.073), platelets-lymphocyte radio (PLR, p = 0.026), platelets-albumin ratio (PAR, p = 0.029) were potential predictors of RE. In multivariate analysis, CCRT [p < 0.001; OR, 3.380; 95% CI, 1.767-6.465], SIRI (p = 0.047; OR, 0.436; 95% CI, 0.192-0.989), and PAR (p = 0.036; OR, 2.907; 95% CI, 1.071-7.891) were independent predictors of grade ≥2 RE. The AUC of nomogram was 0.702 (95% CI, 0.626-0.778), which was greater than each independent predictor (CCRT: 0.645; SIRI: 0.558; PAR: 0.559). Calibration curves showed high coherence between the predicted and actual observation RE, and DCA displayed satisfactory clinical utility.

CONCLUSION

In this study, CCRT, SIRI, and PAR were independent predictors for RE (grade ≥2) in patients with SCLC receiving chemoradiotherapy. We developed and validated a predictive model through these factors. The developed nomogram with superior prediction ability can be used as a quantitative model to predict RE.

Erring Characteristics of Deformable Image Registration-Based Auto-Propagation for Internal Target Volume in Radiotherapy of Locally Advanced Non-Small Cell Lung Cancer

Purpose

Respiratory motion of locally advanced non-small cell lung cancer (LA-NSCLC) adds to the challenge of targeting the disease with radiotherapy (RT). One technique used frequently to alleviate this challenge is an internal gross tumor volume (IGTV) generated from manual contours on a single respiratory phase of the 4DCT via the aid of deformable image registration (DIR)-based auto-propagation. Through assessing the accuracy of DIR-based auto-propagation for generating IGTVs, this study aimed to identify erring characteristics associated with the process to enhance RT targeting in LA-NSCLC.

Methods

4DCTs of 19 patients with LA-NSCLC were acquired using retrospective gating with 10 respiratory phases (RPs). Ground-truth IGTVs (GT-IGTVs) were obtained through manual segmentation and union of gross tumor volumes (GTVs) in all 10 phases. IGTV auto-propagation was carried out using two distinct DIR algorithms for the manually contoured GTV from each of the 10 phases, resulting in 10 separate IGTVs for each patient per each algorithm. Differences between the auto-propagated IGTVs (AP-IGTVs) and their corresponding GT-IGTVs were assessed using Dice coefficient (DICE), maximum symmetric surface distance (MSSD), average symmetric surface distance (ASSD), and percent volume difference (PVD) and further examined in relation to anatomical tumor location, RP, and deformation index (DI) that measures the degree of deformation during auto-propagation. Furthermore, dosimetric implications due to the analyzed differences between the AP-IGTVs and GT-IGTVs were assessed.

Results

Findings were largely consistent between the two algorithms: DICE, MSSD, ASSD, and PVD showed no significant differences between the 10 RPs used for propagation (Kruskal–Wallis test, ps &gt; 0.90); MSSD and ASSD differed significantly by tumor location in the central–peripheral and superior–inferior dimensions (ps &lt; 0.0001) while only in the central–peripheral dimension for PVD (p &lt; 0.001); DICE, MSSD, and ASSD significantly correlated with the DI (Spearman’s rank correlation test, ps &lt; 0.0001). Dosimetric assessment demonstrated that 79% of the radiotherapy plans created by targeting planning target volumes (PTVs) derived from the AP-IGTVs failed prescription constraints for their corresponding ground-truth PTVs.

Conclusion

In LA-NSCLC, errors in DIR-based IGTV propagation present to varying degrees and manifest dependences on DI and anatomical tumor location, indicating the need for personalized consideration in designing RT internal target volume.

Palliative Radiation for Advanced Central Lung Tumors With Intentional Avoidance of the Esophagus (PROACTIVE): A Phase 3 Randomized Clinical Trial

Question

Can modern radiation techniques reduce the risk of radiation-associated esophageal adverse effects in patients with advanced lung cancer?

Findings

In this phase 3 randomized clinical trial of esophageal-sparing intensity-modulated radiotherapy (ES-IMRT) or standard palliative radiotherapy for 90 patients with stage III/IV incurable non–small cell lung cancer, ES-IMRT significantly reduced symptomatic esophagitis (24% [n = 11] vs 2% [n = 1]), but did not significantly improve esophageal-related quality of life.

Meaning

In this trial, the use of ES-IMRT did not definitively improve esophageal quality of life but reduced symptomatic esophagitis in patients with advanced lung cancer who were receiving palliative thoracic radiotherapy; this technique holds merit for translation into clinical practice.

Importance

Palliative thoracic radiotherapy (RT) can alleviate local symptoms associated with advanced non–small cell lung cancer (NSCLC), but esophagitis is a common treatment-related adverse event. Whether esophageal-sparing intensity-modulated RT (ES-IMRT) achieves a clinically relevant reduction in esophageal symptoms remains unclear.

Objective

To examine whether ES-IMRT achieves a clinically relevant reduction in esophageal symptoms compared with standard RT.

Design, Setting, and Participants

Palliative Radiation for Advanced Central Lung Tumors With Intentional Avoidance of the Esophagus (PROACTIVE) is a multicenter phase 3 randomized clinical trial that enrolled patients between June 24, 2016, and March 6, 2019. Data analysis was conducted from January 23, 2020, to October 22, 2021. Patients had up to 1 year of follow-up. Ninety patients at 6 tertiary academic cancer centers who had stage III/IV NSCLC and were eligible for palliative thoracic RT (20 Gy in 5 fractions or 30 Gy in 10 fractions) were included.

Interventions

Patients were randomized (1:1) to standard RT (control arm) or ES-IMRT. Target coverage was compromised to ensure the maximum esophagus dose was no more than 80% of the RT prescription dose.

Main Outcomes and Measures

The primary outcome was esophageal quality of life (QOL) 2 weeks post-RT, measured by the esophageal cancer subscale (ECS) of the Functional Assessment of Cancer Therapy: Esophagus questionnaire. Higher esophageal cancer subscale scores correspond with improved QOL, with a 2- to 3-point change considered clinically meaningful. Secondary outcomes included overall survival, toxic events, and other QOL metrics. Intention-to-treat analysis was used.

Results

Between June 24, 2016, and March 6, 2019, 90 patients were randomized to standard RT or ES-IMRT (median age at randomization, 72.0 years [IQR, 65.6-80.3]; 50 [56%] were female). Thirty-six patients (40%) received 20 Gy and 54 (60%) received 30 Gy. For the primary end point, the mean (SD) 2-week ECS score was 50.5 (10.2) in the control arm (95% CI, 47.2-53.8) and 54.3 (7.6) in the ES-IMRT arm (95% CI, 51.9-56.7) (P = .06). Symptomatic RT-associated esophagitis occurred in 24% (n = 11) of patients in the control arm vs 2% (n = 1) in the ES-IMRT arm (P = .002). In a post hoc subgroup analysis based on the stratification factor, reduction in esophagitis was most evident in patients receiving 30 Gy (30% [n = 8] vs 0%; P = .004). Overall survival was similar with standard RT (median, 8.6; 95% CI, 5.7-15.6 months) and ES-IMRT (median, 8.7; 95% CI, 5.1-10.2 months) (P = .62).

Conclusions and Relevance

In this phase 3 randomized clinical trial, ES-IMRT did not significantly improve esophageal QOL but significantly reduced the incidence of symptomatic esophagitis. Because post hoc analysis found that reduced esophagitis was most evident in patients receiving 30 Gy of RT, these findings suggest that ES-IMRT may be most beneficial when the prescription dose is higher (30 Gy).

Trial Registration

ClinicalTrials.gov Identifier: NCT02752126

Comparison and quantification of different concurrent chemotherapy regimens with radiotherapy in locally advanced non-small cell lung cancer: Clinical outcomes and theoretical results from an extended LQ and TCP model

PURPOSE

To develop a new radiobiological model and compare the efficacy of four concurrent chemotherapy regimens administered with radiotherapy in locally advanced non-small-cell lung cancer (LANSCLC) by in-field locoregional progression-free survival (LPFS).

MATERIALS AND METHODS

151 LANSCLC patients were reviewed and divided into 5 groups according to their concurrent chemotherapy regimens, including 24 patients treated with radiotherapy alone, 30 treated with concurrent 4-week etoposide-cisplatin (EP), 26 with 3-week pemetrexed-cisplatin (AP), 37 with weekly paclitaxel-cisplatin (TP) and 34 with weekly docetaxel-cisplatin (DP). In-field LPFS and toxicities were compared among groups. A novel tumor control probability (TCP) model, LQRGC, incorporating four "R"s of radiobiology, Gompertzian tumor growth and chemotherapeutic effect, was related to in-field LPFS. Chemo-induced biologically effective doses (BEDs) in LQRGC/TCP model were used to quantify the concurrent chemotherapeutic efficacy.

RESULTS

The median follow-up time was 54.5 months. The weekly DP and 4-week EP groups had favorable median in-field LPFS (EP:46.2 months, AP:30.3 months, TP:12.2 months, DP: not reached, radiotherapy alone: 12.2 months, p = 0.001). The 4-week EP group had a higher incidence of ≥grade 3 leukopenia (EP:76.7%, AP:15.4%, TP:24.3%, DP:14.7%, radiotherapy alone: 12.5%, p < 0.001) than the other four. The LQRGC/TCP model fitted well with the in-field LPFS with the average absolute and relative fitting errors of 6.36% and 12.12%. The chemo-induced BEDs of EP, AP, TP and DP were 5.17, 0.63, 1.89 and 2.52 Gy, respectively.

CONCLUSION

The LQRGC/TCP model achieved promising fitting accuracy for in-field LPFS. As quantified by the model, the 4-week EP and weekly DP showed higher chemo-induced BEDs when concurrently administered with radiotherapy in LANSCLC.

Isotoxic investigation of 18F-FDG PET/CT-guided dose escalation with intensity-modulated radiotherapy for LA-NSCLC

PURPOSE

This research compared differences of dosimetric and biological parameters between PET/CT-guided isotoxic SIB-IMRT plans and conventional radiotherapy plans for patients with LA-NSCLC, and it also evaluated the factors that affect dose escalation.

MATERIALS AND METHODS

This study consisted of a retrospective cohort of thirty patients with IIIA-IIIB NSCLC. SIB-IMRT (Plan_iso) and conventional radiotherapy (Plan_primary) plans were generated using auto-planning. Dosimetric parameters such as mean lung dose (MLD) and other indicators were compared. Tumor control probability (TCP) of PTV and normal tissue complication probability (NTCP) of total lung, heart, esophagus, and spinal cord were calculated. The relationships between dose escalation and 3 D length of PTV and other factors were analyzed. Paired-samples t-test, Mann-Whitney U test, and Chi-Square test were performed for comparisons between datasets. A P < .05 was considered statistically significant.

RESULTS

The dosimetric parameters of PTV in Plan_iso were higher than those of PTV in Plan_primary, and there were significant differences (p < .05). Compared with Plan_primary, Plan_iso slightly increased dosimetric parameters of the total lung, heart, spinal cord, esophagus, and MUs. The absolute differences were small. TCPs of PTV in Plan_iso were significantly higher than those in Plan_primary. NTCPs of the total lung, esophagus, and spinal cord in Plan_iso were higher than those in Plan_primary. There were significant differences, but the absolute differences were small. NTCP of heart in Plan_iso was slightly higher than that in Plan_primary, but there was no statistical difference.

CONCLUSIONS

For LA-NSCLC, the SIB based on isotoxic radiotherapy can significantly increase TCP under the premise that the toxicity of OARs is comparable.

Comparison of dose volumetric parameters of oesophagus in the radiation treatment of carcinoma breast with and without oesophagus delineation

Aim:

There are only limited studies available in literature that discuss methods to reduce the oesophageal dose and acute oesophagitis during breast cancer radiotherapy. The aim of this study is to compare dose volumetric parameters of oesophagus in radiation treatment of breast with and without oesophagus delineation.

Methods:

Treatment plans of 44 patients, who underwent chest wall and supraclavicular fossa irradiation, were selected for the study. Oesophagus was later delineated and treatment replanned using three-dimensional conformal radiotherapy (3DCRT) considering oesophagus as an organ at risk (OAR). The dose prescribed was 40 Gy/15 fractions to the planning target volume (PTV). Dose volumetric parameters of oesophagus such as maximum dose (Dmax), mean dose (Dmean), the percentage of oesophagus volume receiving ≥15Gy (V15), ≥25Gy(V25), ≥33Gy(V33) and ipsilateral lung volume parameters V4, V8 and V16 were compared with already executed plans in which oesophagus was not delineated.

Results:

Contouring the oesophagus as an OAR as a part of the radiotherapy treatment for Carcinoma Breast resulted in statistically significant reduction in dose to the oesophagus. No statistically significant change was found in the ipsilateral lung volume parameters. No compromise in plan quality was required as evident from the statistically non-significant differences in Homogeneity index and Conformity index.

Findings:

3DCRT planning with oesophagus delineation can be considered as a method to reduce oesophageal dose and the acute oesophageal toxicity during radiotherapy for carcinoma breast.

[Dosimetric and toxicity comparison of IMRT and 3D-CRT of non-small cell lung cancer]

PURPOSE

Although three-dimensional conformal radiotherapy (3D-CRT) remains the gold standard as a curative treatment for NSCLC when surgery is not possible, intensity modulated radiotherapy (IMRT) is increasingly used routinely. The purpose of this study was to assess the clinical (immediate toxicities) and dosimetric impact of IMRT compared to 3D-CRT in the treatment of locally advanced (stages IIIA to IIIC) non-small cell lung cancer (NSCLC) treated with concomitant radiochemotherapy, while IMRT in lung cancer was implemented in the radiotherapy department of the Jean-Perrin Center.

PATIENTS AND METHODS

Between March 2015 and October 2019, 64 patients treated with concomitant radiochemotherapy were retrospectively included. Thirty-two received 3D-CRT and 32 IMRT. The radiotherapy prescription was 66Gy in 33 fractions of 2Gy.

RESULTS

IMRT has improved coverage of target volumes (V95 increased by 14.81% in IMRT; P<0.001) without increasing doses to OARs and reducing dysphagia (RR=0.67; P=0.027). Low doses to the lung were not significantly increased in IMRT (pulmonary V5 increased by 7.46% in IMRT).

CONCLUSION

Intensity modulated radiotherapy, compared with the standard RC3D technique, improve the coverage of target volumes without increasing the dose to the OARs. It also improves the immediate tolerance of the treatment by reducing the number of dysphagia.

Hypofractionated Intensity Modulated Radiation Therapy With Concurrent Chemotherapy in Locally Advanced Non-Small Cell Lung Cancer: A Phase II Prospective Clinical Trial (GASTO1011)

PURPOSE

We aimed to explore the efficacy and toxicity of split-course hypofractionated radiotherapy with concurrent chemotherapy (HRT-CHT) in patients with locally advanced non-small cell lung cancer (LANSCLC) in this single-arm, phase II study.

METHODS

LANSCLC patients were considered eligible if their forced expiratory volume in 1 second/forced vital capacity (FEV1/FVC%) and carbon monoxide diffusing capacity (DLCO%) were ≥40% and ≥45%, respectively. HRT-CHT using the IMRT technique was administered with 51 Gy in 17 fractions as the first course followed by a break. Patients without disease progression or persistent ≥grade 2 toxicities had an HRT-CHT of 15-18 Gy in 5-6 fractions as a boost. The primary endpoint was progression-free survival (PFS), and the secondary endpoint was overall survival (OS).

RESULTS

Eighty-nine patients were enrolled and analyzed. The median follow-up was 29.5 months for all patients and 35.3 months for the survivors. The objective response rate was 97.8%; the median PFS and OS were 11.0 months and 27.0 months, respectively. Grade 3 acute esophagitis/pneumonitis occurred in 15 (16.9%)/7 (7.9%) patients. Grade 3/5 late pneumonitis occurred in 2 (2.2%)/1 (1.1%) patients. Of the 78 (87.6%) who completed the split-course HRT-CHT per protocol, patients with better FEV1/FVC% and DLCO% after the break had significantly better OS (for the FEV/FVC1%≥80% vs 60-79% vs 41-59% groups, 2-year OS values were 57.2% vs 56.9% vs 0%, respectively, p=0.024; for the DLCO%≥80% vs 60-79% vs 45-59% groups, 2-year OS values were 70.4% vs 48.4% vs 37.5%, respectively, p=0.049).

CONCLUSIONS

Split-course HRT-CHT achieved a promising response rate and survival with tolerable toxicity in LANSCLC. Pulmonary function tests are necessary indicators for radiation treatment planning and dose escalation.

Moderately Hypofractionated Once-Daily Compared With Twice-Daily Thoracic Radiation Therapy Concurrently With Etoposide and Cisplatin in Limited-Stage Small Cell Lung Cancer: A Multicenter, Phase II, Randomized Trial

PURPOSE

Chemotherapy and concurrent thoracic radiation therapy (CCTRT) followed by prophylactic cranial irradiation (PCI) is the standard of care for limited-stage small cell lung cancer (LS-SCLC). We aimed to compare the efficacy and toxicity of moderately hypofractionated once-daily CCTRT with that of a standard twice-daily regimen.

METHODS AND MATERIALS

This multicenter, phase 2, randomized study enrolled patients aged 18 to 75 years old who had pathologically confirmed LS-SCLC and an Eastern Cooperative Oncology Group performance status of 0 to 1. Eligible patients received 4 to 6 cycles of etoposide-cisplatin chemotherapy and were randomized to receive twice-daily CCTRT at 45 Gray (Gy) in 30 fractions or once-daily CCTRT at 65 Gy in 26 fractions, commencing with cycles 1 to 3 of chemotherapy. PCI was given to good responders. The primary endpoint was progression-free survival (PFS).

RESULTS

The analyses included 182 patients, with 94 in the twice-daily group and 88 in the once-daily group. CCTRT started with cycle 3 of chemotherapy for most patients (80.2%). At a median follow-up of 24.3 months, the median PFS was 13.4 months (95% confidence interval [CI], 10.8-16.0) in the twice-daily group versus 17.2 months (95% CI, 11.8-22.6) in the once-daily group (P = .031), with 2-year PFS rates of 28.4% (95% CI, 18.2-38.6) and 42.3% (95% CI, 31.1-53.5), respectively. The estimated overall survival was 33.6 months in the twice-daily group versus 39.3 months in the once-daily group (P = .137). The median locoregional PFS was 23.9 months in the twice-daily group and was not reached in the once-daily group (P = .017). The incidences of most toxicities were similar in both groups, except for a higher incidence of ≥grade 3 acute lymphopenia in the once-daily group (71.7% vs 40.2% in the twice-daily group; P < .001). There was no difference in the incidences of ≥grade 3 esophagitis (17.4% vs 15.3%, respectively), pneumonitis (3.3% vs 2.4%, respectively) or treatment-related death (2.2% vs 1.2%, respectively) between the once-daily and twice-daily groups.

CONCLUSIONS

Moderately hypofractionated, once-daily CCTRT showed improved PFS and similar toxicities compared with twice-daily CCTRT in LS-SCLC. This regimen should be evaluated for comparison in a phase 3 randomized trial.

Developments in radiation techniques for thoracic malignancies

Radiation therapy is a cornerstone of modern lung cancer treatment alongside surgery, chemotherapy, immunotherapy and targeted therapies. Advances in radiotherapy techniques have enhanced the accuracy of radiation delivery, which has contributed to the evolution of radiation therapy into a guideline-recommended treatment in both early-stage and locally advanced nonsmall cell lung cancer. Furthermore, although radiotherapy has long been used for palliation of disease in advanced lung cancer, it is increasingly having a role as a locally ablative treatment in patients with oligometastatic disease.This review provides an overview of recent developments in radiation techniques, particularly for non-radiation oncologists who are involved in the care of lung cancer patients. Technical advances are discussed, and findings of recent clinical trials are highlighted, all of which have led to a changing perception of the role of radiation therapy in multidisciplinary care.

Chemoradiotherapy by intensity-modulated radiation therapy with simultaneous integrated boost in locally advanced or oligometastatic non-small-cell lung cancer-a two center experience

Purpose

Integrating moderate hypofractionation to the macroscopic tumor with elective nodal irradiation while sparing the organs at risk (OAR) in chemoradiotherapy of locally advanced non-small-cell lung cancer.

Methods

From 2010–2018, treatment, patient and tumor characteristics of 138 patients from two radiation therapy centers were assessed. Chemoradiotherapy by intensity-modulated radiation therapy (IMRT) with a simultaneous integrated boost (SIB) to the primary tumor and macroscopic lymph node metastases was used.

Results

A total of 124 (90%) patients received concurrent chemotherapy. 106 (76%) patients had UICC (Union for International Cancer Control) stage ≥IIIB and 21 (15%) patients had an oligometastatic disease (UICC stage IV). Median SIB and elective total dose was 61.6 and 50.4 Gy in 28 fractions, respectively. Furthermore, 64 patients (46%) had an additional sequential boost to the primary tumor after the SIB-IMRT main series: median 6.6 Gy in median 3 fractions. The median cumulative mean lung dose was 15.6 Gy (range 6.2–29.5 Gy). Median follow-up and radiological follow-up for all patients was 18.0 months (range 0.6–86.9) and 16.0 months (range 0.2–86.9), respectively. Actuarial local control rates at 1, 2 and 3 years were 80.4, 68.4 and 57.8%. Median overall survival and progression-free survival was 30.0 months (95% confidence interval [CI] 23.5–36.4) and 12.1 months (95% CI 8.2–16.0), respectively. Treatment-related toxicity was moderate. Radiation-induced pneumonitis grade 2 and grade 3 occurred in 13 (9.8%) and 3 (2.3%) patients.

Conclusions

Chemoradiotherapy using SIB-IMRT showed promising local tumor control rates and acceptable toxicity in patients with locally advanced and in part oligometastatic lung cancer. The SIB concept, resulting in a relatively low mean lung dose, was associated with low numbers of clinically relevant pneumonitis. The overall survival appears promising in the presence of a majority of patients with UICC stage ≥IIIB disease.

Accumulation of the delivered dose based on cone-beam CT and deformable image registration for non-small cell lung cancer treated with hypofractionated radiotherapy

Background

This study aimed to quantify the dosimetric differences between the planned and delivered dose to tumor and normal organs in locally advanced non-small cell lung cancer (LANSCLC) treated with hypofractionated radiotherapy (HRT), and to explore the necessity and identify optimal candidates for adaptive radiotherapy (ART).

Methods

Twenty-seven patients with stage III NSCLC were enrolled. Planned radiation dose was 51Gy in 17 fractions with cone-beam CT (CBCT) acquired at each fraction. Virtual CT was generated by deformable image registration (DIR) of the planning CT to CBCT for dose calculation and accumulation. Dosimetric parameters were compared between original and accumulated plans using Wilcoxon signed rank test. Correlations between dosimetric differences and clinical variables were analyzed using Mann-Whitney U test or Chi-square test.

Results

Patients had varied gross tumor volume (GTV) reduction by HRT (median reduction rate 11.1%, range − 2.9-44.0%). The V₅₁ of planning target volume for GTV (PTV-GTV) was similar between original and accumulated plans (mean, 88.2% vs. 87.6%, p = 0.452). Only 11.1% of patients had above 5% relative decrease in V₅₁ of PTV-GTV in accumulated plans. Compared to the original plan, limited increase (median relative increase < 5%) was observed in doses of total lung (mean dose, V₂₀ and V₃₀), esophagus (mean dose, maximum dose) and heart (mean dose, V₃₀ and V₄₀) in accumulated plans. Less than 30% of patients had above 5% relative increase of lung or heart doses. Patients with quick tumor regression or baseline obstructive pneumonitis showed more notable increase in doses to normal structures. Patients with baseline obstructive atelectasis showed notable decrease (10.3%) in dose coverage of PTV-GTV.

Conclusions

LANSCLC patients treated with HRT had sufficient tumor dose coverage and acceptable normal tissue dose deviation. ART should be applied in patients with quick tumor regression and baseline obstructive pneumonitis/atelectasis to spare more normal structures.

Supplementary Information

Supplementary information accompanies this paper at 10.1186/s12885-020-07617-3.

Cancer cachexia and treatment toxicity

PURPOSE OF REVIEW

Cancer cachexia is a metabolic disturbance resulting in a loss of skeletal muscle mass that is generally not reversed through traditional nutritional interventions. We review on both the impact of nutritional status on cancer treatment side effects, as well as cancer- specific outcomes.

RECENT FINDINGS

Cancer-specific cachexia and sarcopenia are associated with increased treatment-associated toxicity, and overall worse cancer-specific outcomes across all cancer types in surgical, chemotherapeutic, and radiotherapeutic populations. Despite the fact that cancer cachexia is generally thought to be irreversible, there is some evidence that nutritional intervention can be helpful.

SUMMARY

Nutritional status is an important factor to consider in determining cancer therapy. Patients with poor nutritional status should be identified prior to the initiation of therapy and be monitored judiciously.

Quantifying the Interfractional motion of Esophagus Using Daily Cone Beam Computed Tomography with Oral Contrast During Radiation Therapy for Locally Advanced Non-Small Cell Lung Cancer

PURPOSE

To quantify the interfractional motion of the esophagus during fractionated radiation therapy for locally advanced non-small cell lung cancer.

METHODS AND MATERIALS

We registered simulation 4-dimensional computed tomography (CT) and daily cone beam CT (CBCT) and documented the motion of the esophagus centroid at 5-mm interval slices in right-left (RL) and anterior-posterior (AP) directions. Oral barium sulfate was administrated during CBCT to help localize the esophagus. Thirty-five patients were enrolled. Thirty-five 4-dimensional CT scans, 595 CBCT scans, and 25,970 slices were analyzed. The slice-derived motion values for all patients were presented as 2.5 to 97.5 percentiles and ranges stratified by segments. The magnitude of motion for each individual patient was defined as the standard deviation (SD) of daily motion values stratified by segments. Correlations between the magnitude of motion and clinical variables were explored.

RESULTS

The 2.5 to 97.5 percentiles of RL and AP motion were -4.2 to 7.1 and -4.4 to 5.1; -10.3 to 6.0 and -4.3 to 3.8; -8.7 to 5.5 and -6.4 to 2.8; and -9.1 to 4.7 and -5.8 to 3.3 mm for cervical, proximal, middle, and distal thoracic esophagus, respectively. The interfractional motion was direction- and location-dependent. The magnitude of RL motion was greater than that of AP motion for the 4 segments (P < .05). In the RL direction, the magnitude of motion was greater for the middle thoracic esophagus than for the cervical (median SD 2.7 vs 2.0 mm, P = .001) and proximal thoracic esophagus (median SD 2.7 vs 2.1 mm, P = .002). Patients with right lung tumor and bulky lymph nodes tended to display greater RL esophageal motion.

CONCLUSIONS

The interfractional motion of the esophagus can be considerable during radiation therapy in locally advanced non-small cell lung cancer, especially for middle thoracic esophagus in RL direction. Strategies to minimize the effect of interfractional esophageal motion on dosimetry should be considered.

Investigating the loco-regional control of simultaneous integrated boost intensity-modulated radiotherapy with different radiation fraction sizes for locally advanced non-small-cell lung cancer: clinical outcomes and the application of an extended LQ/TCP model

Background

To investigate the loco-regional progression-free survival (LPFS) of intensity-modulated radiotherapy (IMRT) with different fraction sizes for locally advanced non-small-cell lung cancer (LANSCLC), and to apply a new radiobiological model for tumor control probability (TCP).

Methods

One hundred and three LANSCLC patients treated with concurrent radiochemotherapy were retrospectively analyzed. Factors potentially predictive of LPFS were assessed in the univariate and multivariate analysis. Patients were divided into group A (2.0 ≤ fraction size<2.2Gy), B (2.2 ≤ fraction size<2.5Gy), and C (2.5 ≤ fraction size≤3.1Gy) according to the tertiles of fraction size. A novel LQRG/TCP model, incorporating four “R”s of radiobiology and Gompertzian tumor growth, was developed to predict LPFS and compared with the classical LQ/TCP model.

Results

With a median follow-up of 22.1 months, the median LPFS was 23.8 months. Fraction size was independently prognostic of LPFS. The median LPFS of group A, B and C was 13.8, 35.7 months and not reached, respectively. Using the new LQRG/TCP model, the average absolute and relative fitting errors for LPFS were 6.9 and 19.6% for group A, 5.5 and 8.8% for group B, 6.6 and 9.5% for group C, compared with 9.5 and 29.4% for group A, 16.6 and 36.7% for group B, 24.8 and 39.1% for group C using the conventional LQ/TCP model.

Conclusions

Hypo-fractionated IMRT could be an effective approach for dose intensification in LANSCLC. Compared with conventional LQ model, the LQRG model showed a better performance in predicting follow-up time dependent LPFS.

Risk factors for esophagitis after hypofractionated palliative (chemo) radiotherapy for non-small cell lung cancer

Introduction

Esophagitis influences quality of life and might cause treatment interruption and hospitalization. Previous studies of risk factors focused on curative treatment for non-small cell lung cancer (NSCLC), which often involves concomitant chemoradiation (CRT). Given the uncertainty around extrapolation of dose constraints, we analyzed risk factors in patients treated with hypofractionated palliative regimens.

Patients and methods

A retrospective review of 106 patients treated with palliative radiotherapy or CRT between 2009 and 2017 was performed. Inclusion criteria: prescribed total dose 30–54 Gy, dose per fraction 2.5–4 Gy, esophageal dose > 1 Gy. Uni- and multivariate analyses were performed in 97 eligible patients to identify predictive factors for acute esophagitis grade ≥ 1 (CTCAE 5.0).

Results

Forty percent of patients were treated with 15 fractions of 2.8 Gy (42 Gy) and 28% also received chemotherapy according to the CONRAD study regimen (induction and concomitant Carboplatin/Vinorelbine) published by the Norwegian Lung Cancer Group. Thirty-four percent were treated with 10 fractions of 3 Gy. Stage IV NSCLC was present in 47%. Esophagus Dmax was 39 Gy (population median) and Dmean 15 Gy. Overall 31% of patients developed esophagitis (26% grade 2–3, no grade 4–5). Several dosimetric parameters correlated with the risk of esophagitis (Dmax, Dmean, D5cc, V20, V30, V35, V40). Dmax outperformed other dosimetric variables in multivariate analysis. Furthermore, concomitant chemotherapy significantly increased the risk of esophagitis, while oral steroid medication reduced it. In patients with Dmax ≥40 Gy a reduced Dmean (≤20 Gy) was beneficial.

Conclusion

In order to reduce esophagitis after hypofractionated palliative treatment lower doses than those recommended in curative NSCLC settings are preferable. Besides esophageal dose, CRT is the main risk factor for esophagitis. Additional work is needed to confirm that steroids are able to modify the risk (or to rule out confounding effects of baseline variables not included in our database).

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.