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

Adaptive radiation strategy with V20 limitation associates with survival benefit and lower incidence of symptomatic radiation pneumonitis in stage III NSCLC patients receiving concurrent immunotherapy and thoracic radiation

OBJECTIVES

To evaluate the efficacy and the incidence of symptomatic radiation pneumonitis (RP) of the adaptive radiation strategy with V20 limitation in stage III non-small cell lung cancer (NSCLC) patients receiving concurrent immunotherapy and radiotherapy Materials and Methods: We retrospectively reviewed stage III NSCLC patients received thoracic radiation with or without immunotherapy from January 2015 to September 2024 in the Third Xiangya Hospital. The overall survival (OS), progression free survival (PFS), objective response rate (ORR), and the incidence of symptomatic RP were compared among patients stratified by the sequential of immunotherapy and radiotherapy.

RESULTS

45 patients received concurrent immunotherapy and radiotherapy with application of the adaptive radiation strategy (the CIR group). 32 patients received simultaneous integrated boost intensity-modulated radiotherapy (SIB-IMRT), 26 patients received 2 to 4 cycles neoadjuvant immuno-chemotherapy before the concurrent immunotherapy and radiotherapy, 7 patients received thoracic radiotherapy with a prescribed dosage of 50 Gy, and 10 patients received radiotherapy with CTV omission. 86.67 % (39/45) patients had a V20 ≤ 20 %. The ORR was 86.67 %. The median PFS of these patients was significantly longer than those received concurrent chemo-radiotherapy followed by immunotherapy (the PACIFIC paradigm, HR, 2.40; 95 % CI, 1.15 to 5.02; log-rank p = 0.013; median, 28.6 vs. 16.1 months p = 0.013). The median OS was not reached. 13.3 % patients in the CIR group experienced grade ≥ 2 RP and the incidence was significantly lower than that of patients received radiotherapy without immunotherapy or concurrent chemo-radiotherapy with immunotherapy consolidation.

CONCLUSIONS

The application of adaptive radiotherapy strategies with V20 limitation demonstrated robust antitumor activity and reduced pulmonary toxicity in stage III NSCLC patients receiving concurrent ICIs treatment and thoracic radiation. This treatment modality deserves further validation as a promising therapy in patients with treatment-naive, unresectable, stage III NSCLC.

Pneumonitis Risk After Chemoradiotherapy With and Without Immunotherapy in Patients With Locally Advanced Non-Small Cell Lung Cancer: A Systematic Review and Meta-Analysis

PURPOSE

Chemoradiotherapy (CRT) combined with immune checkpoint inhibitors (ICIs) is the standard of care for patients with unresectable and locally advanced non-small cell lung cancer. This study aimed to determine whether the addition of ICIs to CRT is associated with an increased risk of pneumonitis.

METHODS AND MATERIALS

The PubMed, Embase, Cochrane Library, and Web of Science databases were searched for eligible studies published between January 1, 2015, and July 31, 2023. The outcome of interest was the incidence rate of pneumonitis. A random-effects model was used for statistical analysis.

RESULTS

A total of 185 studies with 24,527 patients were included. The pooled rate of grade ≥2 pneumonitis for CRT plus ICIs was significantly higher than that for CRT alone (29.6%; 95% CI, 25.7%-33.6% vs 20.2%; 95% CI, 17.7%-22.8%; P < .0001) but not that of grade ≥3 (5.7%; 95% CI, 4.8%-6.6% vs 5.6%; 95% CI, 4.7%-6.5%; P = .64) or grade 5 (0.1%; 95% CI, 0.0%-0.2% vs 0.3%; 95% CI, 0.1%-0.4%; P = .68). The results from the subgroup analyses of prospective studies, retrospective studies, Asian and non-Asian studies, concurrent CRT (cCRT), and durvalumab consolidation were comparable to the overall results. However, CRT or cCRT plus PD-1 inhibitors not only significantly increased the incidence of grade ≥2 but also that of grade ≥3 pneumonitis compared to CRT alone or cCRT plus PD-L1 inhibitors.

CONCLUSIONS

Compared with CRT alone, durvalumab consolidation after CRT appears to be associated with a higher incidence of moderate pneumonitis and CRT plus PD-1 inhibitors with an increased risk of severe pneumonitis. Nevertheless, these findings are based on observational studies and need to be validated in future large head-to-head studies.

Coronavirus disease 2019 and lung cancer: where are we?

Oncology patients are more susceptible to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection due to hospital contact and an immunological system that can be compromised by antineoplastic therapy and supportive treatments. Certain similarities have been described in the physiopathology of coronavirus disease 2019 (COVID-19) and lung cancer (LC) that may explain the higher probability of these patients of developing a more serious disease with more frequent hospitalizations and even death, especially with the addition of smoking, cardiovascular and respiratory comorbidities, old age and corticosteroids use. Pre-existing lesions and cancer therapies change the normal architecture of the lungs, so diagnostic scales such as COVID-19 Reporting and Data System (CO-RADS) are of vital importance for a correct diagnosis and patient homogenization, with a high inter-observer correlation. Moreover, anticancer treatments have required an adaptation to reduce the number of visits to the hospital [hypofractionated radiotherapy (RT), larger intervals between chemotherapy cycles, delay in follow-up tests, among others]. In a way, this has also caused a delay in the diagnosis of new cancers. On the other hand, vaccination has had a positive impact on the mortality of these patients, who maintain a similar seroprevalence to the rest of the population, with a similar impact in mortality.

Comparison of post-chemoradiotherapy pneumonitis between Asian and non-Asian patients with locally advanced non-small cell lung cancer: a systematic review and meta-analysis

Background

Pneumonitis is a common complication for patients with locally advanced non-small cell lung cancer undergoing definitive chemoradiotherapy (CRT). It remains unclear whether there is ethnic difference in the incidence of post-CRT pneumonitis.

Methods

PubMed, Embase, Cochrane Library, and Web of Science were searched for eligible studies from January 1, 2000 to April 30, 2023. The outcomes of interest were incidence rates of pneumonitis. The random-effect model was used for statistical analysis. This meta-analysis was registered with PROSPERO (CRD42023416490).

Findings

A total of 248 studies involving 28,267 patients were included. Among studies of CRT without immunotherapy, the pooled rates of pneumonitis for Asian patients were significantly higher than that for non-Asian patients (all grade: 66.8%, 95% CI: 59.2%-73.9% vs. 28.1%, 95% CI: 20.4%-36.4%; P < 0.0001; grade ≥2: 25.1%, 95% CI: 22.9%-27.3% vs. 14.9%, 95% CI: 12.0%-18.0%; P < 0.0001; grade ≥3: 6.5%, 95% CI: 5.6%-7.3% vs. 4.6%, 95% CI: 3.4%-5.9%; P = 0.015; grade 5: 0.6%, 95% CI: 0.3%-0.9% vs. 0.1%, 95% CI: 0.0%-0.2%; P < 0.0001). Regarding studies of CRT plus immunotherapy, Asian patients had higher rates of all-grade (74.8%, 95% CI: 63.7%-84.5% vs. 34.3%, 95% CI: 28.7%-40.2%; P < 0.0001) and grade ≥2 (34.0%, 95% CI: 30.7%-37.3% vs. 24.6%, 95% CI: 19.9%-29.3%; P = 0.001) pneumonitis than non-Asian patients, but with no significant differences in the rates of grade ≥3 and grade 5 pneumonitis. Results from subgroup analyses were generally similar to that from the all studies. In addition, the pooled median/mean of lung volume receiving ≥20 Gy and mean lung dose were relatively low in Asian studies compared to that in non-Asian studies.

Interpretation

Asian patients are likely to have a higher incidence of pneumonitis than non-Asian patients, which appears to be due to the poor tolerance of lung to radiation. Nevertheless, these findings are based on observational studies and with significant heterogeneity, and need to be validated in future large prospective studies focusing on the subject.

Funding

None.

CT-based radiomics nomogram may predict who can benefit from adaptive radiotherapy in patients with local advanced-NSCLC patients

BACKGROUND

Although adaptive radiotherapy (ART) has many advantages, ART is not universal in the clinical appliance due to the consumption of a lot of labor, and economic burden. It is necessary to explore a CT stimulation-based radiomics model for screening who can get more benefits from ART in locally advanced non-small cell lung cancer (NSCLC) patients.

METHOD

183 cases of NSCLC patients receiving concurrent chemoradiotherapy with an adaptive approach were enrolled as a primary cohort, while 28 cases from another hospital served as an independent external validation cohort. Tumor regression assessment was conducted based on GTV reduction (Criteria A) or according to RECIST Version 1.1(Criteria B). The radiomics features were extracted by the "PyRadiomics" package and further screened by the LASSO method. Then, logistic regression was used to establish the model. Bootstrap and external validation were applied to verify the stability of the model. The receiver operating characteristic (ROC) curve was delineated to assess the predictive efficacy of the radiomics model. Dose-volume histograms were quantitatively compared between the initial and composite ART plans. Clinical endpoints included overall survival (OS) and progression-free survival (PFS).

RESULT

There were no significant differences in clinical features between tumor regression-resistant (RR) and tumor regression-sensitivity (RS) groups. The AUC values of the Criteria A model and Criteria B model were 0.767 and 0.771, respectively. Bootstrapping validation and external validation confirmed the stability of models. In all patients, there was a significant benefit of ART in the lung, heart, cord, and esophagus compared to non-ART, particularly in RS patients. Furthermore, PFS and OS from ART were significantly longer in RS as defined by Criterion B than in RR patients with the same ART application.

CONCLUSION

CT-based radiomics can screen out the patients who can gain more benefits from ART, which contribute to guiding and popularizing the application of ART strategy in the clinic within economic benefits and feasibility.

Superiority of integrated cervicothoracic immobilization in the setup of lung cancer patients treated with supraclavicular station irradiation

Objective

To investigate the superiority of the integrated cervicothoracic immobilization devices (ICTID) on the mobility of the supraclavicular station in lung cancer patients requiring both primary lung lesion and positive supraclavicular lymph nodes irradiation.

Methods

One hundred patients with lung cancer were prospectively enrolled in the study. The following four different fixation methods are used for CT simulation positioning: thoracoabdominal flat immobilization device fixation with arms lifting (TAFID group), head-neck-shoulder immobilization device fixation with arms on the body sides (HNSID group), ICTID fixation with arms on the body sides (ICTID arms-down group), and n ICTID fixation with arms lifting (ICTID arms-up group). Cone-beam computed tomography (CBCT) images are taken daily or weekly before treatment, to assess anatomical changes during the radiotherapy course.

Results

The translation errors in X (left-right direction), Y (head-foot direction), and Z (abdomen-back direction) directions of the ICTID arms-up, TAFID, ICTID arms-down and HNSID groups were (0.15 ± 0.18) cm, (0.15 ± 0.16) cm, (0.16 ± 0.16) cm, and (0.15 ± 0.20) cm; (0.15 ± 0.15) cm, (0.21 ± 0.25) cm, (0.28 ± 0.23) cm, and (0.27 ± 0.21) cm; (0.13 ± 0.14) cm, (0.15 ± 0.14) cm, (0.17 ± 0.13) cm, and (0.16 ± 0.14) cm, respectively. Among them, the ICTID arms-up group had the minimal setup errors in X direction than those in ICTID arms-down (p=0.001) and HNSID groups (p=0.001), and in Y direction than those in TAFID (p<0.001), and in Z direction than those in ICTID arms-down (p<0.001) and TAFID groups (p=0.034). For the rotational errors of the four groups in the directions of sagittal plane, transverse plane, and coronal plane, the ICTID arms-up group had the smallest setup errors in the sagittal plane than that of TAFID groups and similar rotation setup errors with those of the other three groups.

Conclusion

For patients requiring radiation of primary lung lesion and positive supraclavicular lymph nodes, an integrated frame fixation device is preferred the ICTID arms-up methods provide the smallest set up error and satisfied repeatability of body position, compared with TAFID and HNSID.

Escalation of radiotherapy dose in large locally advanced drug-resistant gastrointestinal stromal tumors by multi-shell simultaneous integrated boost intensity-modulated technique: a feasibility study

BACKGROUND

Resistance to conventional dose schemes and radiotoxicity of healthy tissue is a clinical challenge in the radiation therapy of large locally advanced drug-resistant gastrointestinal stromal tumor (LADR-GIST). This study aimed to assess the feasibility of using multi-shell Simultaneous Integrated Boost Intensity-Modulated modality (SIB-IMRT) strategy to provide a safe and effective escalation dose regimen for LADR-GIST.

METHODS

7 patients with LADR-GIST were selected in this study. The modified SIB-IMRT plans for all patients were generated by delivering different escalation-dose gradients to four ring shaped regions (shells) within the gross tumor volume (GTV). The doses of the central volume of the tumor (GTVcenter) were escalated up to 70-92.5 Gy (25 fractions), while the doses of planning target volume (PTV) and shell-1 were kept at 50.0 Gy. Based on different escalation-dose gradients, the modified SIB-IMRT plans were divided into four groups (SIB-IMRT groups). For comparison purposes, plans obtained by conventional IMRT technique (Con-IMRT) with 50 Gy (25 fractions) were also generated for all patients (Con-IMRT group). All plans were normalized to cover 95% of the PTV with the prescribed dose of 50.0 Gy. The equivalent uniform dose (EUD), relative equivalent uniform dose (rEUD), dose volume histogram (DVH), dose profile, conformity index (CI) and monitor unit (MU) were evaluated in five groups. The Friedman Test was performed to determine whether there were significant differences (P < 0.05).

RESULTS

Compared with the Con-IMRT group, the EUD of GTV (EUDGTV) and rEUD of SIB-IMRT groups were improved when escalation-dose gradient was increased, and the improvement became significant when the escalation-dose gradient reached 20% of the prescription dose. The rEUD tended to be stable as the escalation-dose gradient went up to 25% of the prescription dose. There were no significant differences in CIs and DVH metrics for OARs between the Con-IMRT group and any SIB-IMRT group, but the significant differences were observed between the SIB10-IMRT group and the SIB25-IMRT group. For the SIB-IMRT groups, as the dose gradient became steeper in the dose profiles, the higher dose was mainly accumulated in the inner part of GTV accompanied with a higher MU.

CONCLUSIONS

The proposed multi-shell SIB-IMRT strategy is feasible in dosimetry for LADR-GIST and can acquire higher therapeutic gain without sacrifice of healthy tissues. It appears that the scheme of delivering 20% of the prescribed escalation-dose gradient to the target volume can provide satisfactory dose irradiation for LADR-GIST, and it should be evaluated in future clinical study.

The critical components for effective adaptive radiotherapy in patients with unresectable non-small-cell lung cancer: who, when and how

Adaptive radiotherapy (ART) is a new radiotherapy technology based on image-guided radiation therapy technology, used to avoid radiation overexposure to residual tumors and the surrounding normal tissues. Tumors undergoing the same radiation doses and modes can occur unequal shrinkage due to the variation of response times to radiation doses in different patients. To perform ART effectively, eligible patients with a high probability of benefits from ART need to be identified. Confirming the precise timetable for ART in every patient is another urgent problem to be resolved. Moreover, the outcomes of ART are different depending on the various image guidance used. This review discusses 'who, when and how' as the three key factors involved in the most effective implementation for the management of ART.

Efficacy and Safety of Simultaneous Integrated Boost Intensity-Modulation Radiation Therapy Combined with Systematic and Standardized Management for Esophageal Cancer

Objective

To analyze and compare the efficacy and safety of simultaneous integrated boost intensity-modulation radiation therapy (SIB-IMRT) combined with systematic and standardized management for esophageal cancer.

Methods

From January 2012 to January 2019, 200 patients with esophageal cancer who received radical chemoradiotherapy in our hospital were treated with lymphatic drainage area radiation prevention combined with systematic and standardized management. According to difference in radiotherapy methods, the patients were divided into local lesion 92 patients treated with simultaneous integrated boost intensity-modulation radiation therapy (SIB-IMRT) combined with systematic standardized management (SIB-IMRT group), and late course boost intensity-modulation radiation therapy (LCB-IMRT) combined with systematic standardized management 108 patients (LCB-IMRT group). The short-term eficacy of the two groups were compared. The dose volume parameters of the organ in danger are evaluated based on the dose volume histogram. The related adverse reactions during chemoradiotherapy were compared between two groups. The local control rate and survival rate were compared between the two groups.

Results

The recent total effective rates of rats in the SIB-IMRT group and LCB-IMRT group were 95.65% and 90.74%, respectively, and there was no significant difference between the two groups (p > 0.05). The mean doses to left and right lung, heart and spinal cord in the SIB-IMRT group were significantly lower than that in the LCB-IMRT group (p < 0.05). There was no significant difference in the incidence of adverse reactions such as radiation esophagitis, radiation pneumonitis, radiation tracheitis, gastrointestinal reaction and bone marrow suppression between the SIB-IMRT group and LCB-IMRT groups (p > 0.05). The one-year and three-year overall survival rates in the SIB-IMRT group and LCB-IMRT groups were 82.61%, 42.39% and 77.78%, 34.26%, respectively, and the median survival times were 38 and 29 months, respectively. The local control rates in the SIB-IMRT group and LCB-IMRT group in one and three years were 84.78%, 56.52% and 75.93%, 41.67%, respectively. The 3-year local control rate in the SIB-IMRT group was higher than that in the LCB-IMRT group (p < 0.05), but there was no significant difference in the 1-and 3-year overall survival rates between the two groups (p > 0.05).

Conclusion

SIB-IMRT combined with systematic and standardized management in the treatment of esophageal cancer can reduce the amount of some organs at risk and improve the local control rate of the lesion.

The time-series behavior of systemic inflammation-immune status in predicting survival of locally advanced non-small cell lung cancer treated with chemoradiotherapy

Background

Systematic inflammation is believed to play a crucial role in tumorigenesis and metastasis. This study aims at evaluating the prognostic value of time-series behavior of systematic inflammation-immune status before and after definitive chemoradiotherapy (dCRT) in patients with locally advanced non-small cell lung cancer (LA-NSCLC).

Methods

The relationship between systematic inflammation-immune score (SIS, defined as pretreatment peripheral platelet count × neutrophil count/lymphocyte count) and the prognosis was tested in a retrospective study of 386 consecutive LA-NSCLC patients (Group A) with pretreatment SIS and 161 patients (Group B) with SIS before and one month after the dCRT.

Results

SIS of 1400 × 109 was found to be an optimal cutoff point to stratify the patients into high (>1400 × 109) and low (≤1400 × 109) SIS groups. Univariate and multivariate analyses revealed that the SIS, whether before or after dCRT, was an independent predictor for overall survival (OS), progress-free survival (PFS), and distant metastasis-free survival (DMFS). High SIS (>1400 × 109) was shown to predict poor 3-year OS (P=0.006, hazard ratio [HR]=2.427), PFS (P=0.001, HR=2.442) and DMFS (P=0.015, HR=2.119). However, SIS was not related to local regional recurrence-free survival in either Group A (P=0.346) or Group B (P=0.486). Further, the area under the receiver operating characteristic curve of the SIS for OS was higher than the neutrophil count/lymphocyte count ratio, platelet count/lymphocyte count ratio, and other conventional clinic-pathological indices.

Conclusions

The SIS is a stable and more sensitive survival predictor than other inflammation-based factors and conventional clinical indices, which may aid in more accurately stratifying patients for risk assessment and treatment decisions.

Hypofractionated radiation therapy for unresectable or metastatic sarcoma lesions

Purpose

Given the relative radioresistance of sarcomas and their often large size, conventional palliative radiation therapy (RT) often offers limited tumor control and symptom relief. We report on our use of hypofractionated RT (HFRT) as a strategy to promote durable local disease control and optimize palliation.

Methods and Materials

We retrospectively reviewed 73 consecutive patients with sarcoma who received >10 fractions of HFRT from 2017 to 2020. Clinical scenarios included: (1) palliative or symptomatic intent (34%), (2) an unresectable primary (27%), (3) oligometastatic disease (16%), and (4) oligoprogressive disease (23%).

Results

The HFRT target was a primary tumor in 64% of patients with a median dose of 45 Gy in 15 fractions (59% ≥45 Gy). The 1-year disease-specific survival was 59%, which was more favorable for patients receiving HFRT for oligometastatic (1-year 100%) or oligoprogressive (1-year 73%) disease (P = .001). The 1-year local control (LC) of targeted lesions was 73%. A metastatic target (1-year 95% vs 60% primary; P = .02; hazard ratio, 0.27; P = .04) and soft tissue origin (1-year 78% vs 61% bone; P = .01; hazard ratio, 0.33; P = .02) were associated with better LC. The rate of distant failure was high with a 6-month distant metastasis-free survival of only 43%. For patients not planned for adjuvant systemic therapy (n = 53), the median systemic therapy break was 9 months and notably longer in oligometastatic (13 months), oligoprogressive (12 months) or unresectable (13 months) disease. HFRT provided palliative relief in 95% of cases with symptoms. Overall, 49% of patients developed acute grade 1 to 2 RT toxicities (no grade 3-5). No late grade 2 to 5 toxicities were observed.

Conclusions

HFRT is an effective treatment strategy for patients with unresectable or metastatic sarcoma to provide durable LC, symptom relief, and systemic therapy breaks with limited toxic effects.

Effect of Intensity Modulated Radiotherapy (IMRT) on the immunity, physical status and clinical effect of locally advanced NSCLC patients

Objectives:

To evaluate the clinical value of radiotherapy combined with Camrelizumab in treating locally advanced non-small cell lung cancer (NSCLC) patients.

Methods:

80 locally advanced NSCLC patients were randomly divided into two groups (n=40). The control group was administered with intensity modulated radiation therapy (IMRT), whereas the experimental group with Camrelizumab in addition to IMRT. All the patients underwent clinical efficacy evaluation in terms of adverse drug reaction (ADR), physical status improvement after the treatment, and changes in T lymphocyte subpopulations (incl. CD3⁺, CD4⁺, CD8⁺, CD4⁺/CD8⁺).

Results:

The efficacy was found to be 70% and 47.5 in experimental group and control group, respectively, with the former being significantly better than the latter (p=0.03). The ADR rates were 50% and 37.5% in the experimental group and control group, respectively; but the difference remained insignificant (p=0.26). As for physical status improvement, experimental group evidently excelled the control group (p=0.04). The post-treatment indicators such as CD3⁺, CD4⁺, CD8⁺, CD4⁺/CD8⁺ were significantly more improved in the experimental group than the control group (CD3⁺, p=0.02; CD4⁺, p=0.00; and CD4⁺/CD8⁺, p=0.01). However, the changes in CD8+ were not significant at all (p=0.46).

Conclusions:

The combined therapy of IMRT with Camrelizumab appeared effective in dealing with the locally advanced NSCLC patients, as such patients presented significantly better immune state and physical status improvement but not increased ADR. The therapy is both safe and effective.

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.

Adaptive intensity-modulated radiotherapy with simultaneous integrated boost for stage III non-small cell lung cancer: Is a routine adaptation beneficial?

PURPOSE

Tumor and anatomical changes during radiotherapy have been observed in stage III non-small cell lung cancer (NSCLC) from many previous studies. We hypothesized that a routinely scheduled adaptive radiotherapy would have clinical important dose benefits to lower the risk of toxicities, without increasing the tumor recurrences.

METHODS

We retrospectively reviewed 92 consecutive patients with inoperable stage III NSCLC between November 2017 and March 2019. All eligible patients should received simultaneously integrated boost (SIB) using intensity-modulated radiation therapy (IMRT). A mid-treatment CT simulation and a new adapted plan were routinely given after the first 20 fractions. The organs at risk (OARs) were delineated per RTOG 1106 atlas. Dose-volume histograms were quantitatively compared between the initial and composite adaptive plans. Logistic regression was applied to analyze the dose-response relationship. Clinical endpoints included acute symptomatic radiation pneumonitis (RP2) and esophagitis (RE2), local and regional tumor control, and progression-free survival (PFS).

RESULTS

Sixty-four eligible patients received adaptive SIB-IMRT were consecutively included. The GTVs reduced by a median of -38.2% after 42 to 44 Gy in 20 fractions of radiotherapy. By adapting to tumor and anatomical changes, dosimetric parameters of OARs decreased significantly. The mean lung dose decreased by an average of -74.8 cGy, and mean esophagus dose was lower by 183.1 cGy. We found grade 2 or higher acute RP in 11 patients (17.2%), and RE2 in 28 patients (43.8%). Commonly used lung and esophagus dose metrics were significantly associated with RP2 and RE2. The adaptation could reduce RP2 probability by 3%, and RE2 risk by 5%. Subgroups with higher OARs dose or larger tumor shrinkage may get more dose and toxicities benefits. The estimated median PFS was 12.5 months from the start of radiotherapy.

CONCLUSIONS

We demonstrated that the routinely adaptive SIB-IMRT strategy could significantly reduce the dose to surrounding normal tissues, potentially lower the associated acute RP and RE, without increasing the risk of tumor recurrences.

A Special Report on 2019 International Planning Competition and a Comprehensive Analysis of Its Results

Purpose

The aim of this work is to introduce the 2019 International Planning Competition and to analyze its results.

Methods and materials

A locally advanced non-small cell lung cancer (LA-NSCLC) case using the simultaneous integrated boost approach was selected. The plan quality was evaluated by using a ranking system in accordance with practice guidelines. Planners used their clinical Treatment Planning System (TPS) to generate the best possible plan along with a survey, designed to obtain medical physics aspects information. We investigated the quality of the large population of plans designed by worldwide planners using different planning and delivery systems. The correlations of plan quality with relevant planner characteristics (work experience, department scale, and competition experience) and with technological parameters (TPS and modality) were examined.

Results

The number of the qualified plans was 287 with a wide range of scores (38.61–97.99). The scores showed statistically significant differences by the following factors: 1) department scale: the mean score (89.76 ± 8.36) for planners from the departments treating >2,000 patients annually was the highest of all; 2) competition experience: the mean score for the 107 planners with previous competition experience was 88.92 ± 9.59, statistically significantly from first-time participants (p = .001); 3) techniques: the mean scores for planners using VMAT (89.18 ± 6.43) and TOMO (90.62 ± 7.60) were higher than those using IMRT (82.28 ± 12.47), with statistical differences (p <.001). The plan scores were negligibly correlated with the planner’s years of work experience or the type of TPS used. Regression analysis demonstrated that plan score was associated with dosimetric objectives that were difficult to achieve, which is generally consistent with a clinical practice evaluation. However, 51.2% of the planners abandoned the difficult component of total lung receiving a dose of 5 Gy in their plan design to achieve the optimal plan.

Conclusion

The 2019 international planning competition was carried out successfully, and its results were analyzed. Plan quality was not correlated with work experiences or the TPS used, but it was correlated with department scale, modality, and competition experience. These findings differed from those reported in previous studies.

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.

GOECP/SEOR clinical recommendations for lung cancer radiotherapy during the COVID-19 pandemic

The coronavirus disease 2019 crisis has had a major and highly complex impact on the clinical practice of radiation oncology worldwide. Spain is one of the countries hardest hit by the virus, with devastating consequences. There is an urgent need to share experiences and offer guidance on decision-making with regard to the indications and standards for radiation therapy in the treatment of lung cancer. In the present article, the Oncological Group for the Study of Lung Cancer of the Spanish Society of Radiation Oncology reviews the literature and establishes a series of consensus-based recommendations for the treatment of patients with lung cancer in different clinical scenarios during the present pandemic.

Targeting human epidermal growth factor receptor 2 enhances radiosensitivity and reduces the metastatic potential of Lewis lung carcinoma cells

BACKGROUND

Sublethal radiation induces matrix metalloproteinase 9 (MMP-9)-mediated radioresistance in Lewis lung carcinoma (LLC) cells and their metastatic dissemination. We aim to determine if EGFR/HER2 activation associates with MMP-9-mediated radioresistance and invasiveness in irradiated LLC cells.

METHODS

LLC cells were treated with erlotinib or afatinib followed by sublethal radiation. After irradiation, we examined the phosphorylation of EGFR/HER2 and MMP-9 expression. Colony formation assay determined if the kinase inhibitors sensitize LLC cells to radiation. Matrigel-coated Boyden chamber assay assessed cellular invasiveness. Resulting tumors of wild-type LLC cells or HER2 knock-down mutant cells were irradiated to induce pulmonary metastases.

RESULTS

Afatinib more effectively sensitized LLC cells to radiation and decreased invasiveness by inhibiting phosphorylation of EGFR, HER2, Akt, ERK, and p38, and down-regulating MMP-9 when compared to erlotinib. Afatinib abolished radiation-induced lung metastases in vivo. Furthermore, LLC HER2 knock-down cells treated with radiation had growth inhibition.

CONCLUSION

Dual inhibition of radiation-activated EGFR and HER2 signaling by afatinib suppressed the proliferation and invasion of irradiated LLC cells. Increased radiosensitivity and decreased metastatic dissemination were observed by pharmacological or genetic HER2 inhibition in vivo. These findings indicate that HER2 plays a pivotal role in enhancing radioresistance and reducing metastatic potential of LLC cells.

[Application of Simultaneous Integrated Boost Intensity Modulated Radiotherapy in Locally Advanced Non-small Cell Lung Cancer]

背景与目的

局部晚期非小细胞肺癌（non-small cell lung cancer, NSCLC）的标准治疗方案为放疗联合化疗，但其生存仍不令人满意。随着调强放疗技术的发展，同步推量（simultaneous integrated boost, SIB）技术成为局部晚期NSCLC的研究方向。本研究拟探讨局部晚期NSCLC采用SIB调强放疗技术的有效性和安全性。

方法

回顾性分析北京大学肿瘤医院2015年6月-2018年12月采用SIB技术进行放疗的局部晚期NSCLC患者资料，采用Kaplan-Meier方法进行统计分析，分析其疗效、生存及治疗相关毒性。

结果

研究纳入93例患者，中位随访时间34.23个月，3年生存率、无进展生存率、无局部区域复发生存率和无远处转移生存率分别为53.0%、37.0%、50.5%和50.5%。3级放射性食管炎发生率为5.4%，≥3级放射性肺炎发生率为2.2%。

结论

局部晚期NSCLC采用SIB调强放疗技术安全有效。