Estimating the need for radiotherapy for lung cancer: an evidence-based, epidemiologic approach

Assessment of Lung Cancer YouTube Videos for Patient Education

The internet is essential for obtaining information about lung cancer, which is the leading contributor to global cancer deaths. YouTube is a video-streaming platform that is popular among health consumers; however, the reliability of videos is variable, and few studies have evaluated their role in lung cancer education. This study uses a systematic approach to assess the characteristics, reliability and use of best practices of lung cancer YouTube videos for patient education. Using the search term "lung cancer," the first 50 YouTube videos were identified after applying exclusion criteria and removing duplicates. Two reviewers used a video assessment tool to evaluate 10 videos with minimal discrepancies. The remaining 40 videos were evaluated by one reviewer following a design based research approach. Under half the videos were published within 3 years. Mean video length was 6 min and 12 s. Video publishers were commonly from the USA (70%); were affiliated with a health care facility/ organization (30%), non-profit (26%) or commercial organization (30%); had a physician presenter (46%); were targeted towards patients (68%); and had subtitles (96%). Seventy four percent of videos supported optimal learning by including effective audio and visual channels. Lung cancer epidemiology, risk factors, and definitions (nature of the disease and classification) were among the most common topics covered. Prognostic and diagnostic information was covered less than expected. The reliability of the videos (measured by Modified DISCERN score) varied by presenter type; however, these results should be interpreted cautiously due to the absence of gold standard tools. This study encourages those producing health education videos to continue following best practices for video learning and provides strategies for healthcare providers and patients to support patient education.

DAART: a deep learning platform for deeply accelerated adaptive radiation therapy for lung cancer

Purpose

The study aimed to implement a novel, deeply accelerated adaptive radiation therapy (DAART) approach for lung cancer radiotherapy (RT). Lung cancer is the most common cause of cancer-related death, and RT is the preferred medically inoperable treatment for early stage non-small cell lung cancer (NSCLC). In the current lengthy workflow, it takes a median of four weeks from diagnosis to RT treatment, which can result in complete restaging and loss of local control with delay. We implemented the DAART approach, featuring a novel deepPERFECT system, to address unwanted delays between diagnosis and treatment initiation.

Materials and methods

We developed a deepPERFECT to adapt the initial diagnostic imaging to the treatment setup to allow initial RT planning and verification. We used data from 15 patients with NSCLC treated with RT to train the model and test its performance. We conducted a virtual clinical trial to evaluate the treatment quality of the proposed DAART for lung cancer radiotherapy.

Results

We found that deepPERFECT predicts planning CT with a mean high-intensity fidelity of 83 and 14 HU for the body and lungs, respectively. The shape of the body and lungs on the synthesized CT was highly conformal, with a dice similarity coefficient (DSC) of 0.91, 0.97, and Hausdorff distance (HD) of 7.9 mm, and 4.9 mm, respectively, compared with the planning CT scan. The tumor showed less conformality, which warrants acquisition of treatment Day1 CT and online adaptive RT. An initial plan was designed on synthesized CT and then adapted to treatment Day1 CT using the adapt to position (ATP) and adapt to shape (ATS) method. Non-inferior plan quality was achieved by the ATP scenario, while all ATS-adapted plans showed good plan quality.

Conclusion

DAART reduces the common online ART (ART) treatment course by at least two weeks, resulting in a 50% shorter time to treatment to lower the chance of restaging and loss of local control.

Association of long noncoding RNA MALAT1 with the radiosensitivity of lung adenocarcinoma cells via the miR-140/PD-L1 axis

Objective

To investigate the effect of MALAT1 on the modulating the radiosensitivity of lung adenocarcinoma, through regulation of the expression of the miR-140/PD-L1 axis.

Methods

The online databases UALCAN and dbDEMC were searched for the MALAT1 and miR-140 expressions in patients with lung adenocarcinoma (LUAD), respectively. Then analyze their relationship with overall survival rates separately in the UALCAN and ONCOMIR databases. A functional analysis was performed for A549 cells by transfecting small-interfering RNAs or corresponding plasmids after radiotherapy. Xenograft models of LUAD exposed to radiation were established to further observe the effects of MALAT1 on the radiosensitivity of LUAD. The luciferase assay and reverse transcription-polymerase chain reaction were performed to assess the interaction between miR-140 and MALAT1 or PD-L1.

Results

MALAT1 were overexpressed in human LUAD tumor tissues and cell lines, while miR-140 were inhibited. MALAT1 knockdown or miR-140 increase suppressed cell proliferation and promoted cell apoptosis in LUAD after irradiation. LUAD xenograft tumor growth was also inhibited by MALAT1 knockdown combined with irradiation. miR-140 could directly bind with MALAT1 or PD-L1. Furthermore, MALAT1 knockdown inhibited PD-L1 mRNA and protein expressions by upregulating miR-140 in LUAD cells.

Conclusion

MALAT1 may function as a sponge for miR-140a-3p to enhance the PD-L1 expression and decrease the radiosensitivity of LUAD. Our results suggest that MALAT1 might be a promising therapeutic target for the radiotherapy sensitization of LUAD.

Early Prediction of Radiation-Induced Pulmonary Fibrosis Using Gastrin-Releasing Peptide Receptor-Targeted PET Imaging

Early diagnosis of radiation-induced pulmonary fibrosis (RIPF) in lung cancer patients after radiation therapy is important. A gastrin-releasing peptide receptor (GRPR) mediates the inflammation and fibrosis after irradiation in mice lungs. Previously, our group synthesized a GRPR-targeted positron emission tomography (PET) imaging probe, [⁶⁴Cu]Cu-NODAGA-galacto-bombesin (BBN), an analogue peptide of GRP. In this study, we evaluated the usefulness of [⁶⁴Cu]Cu-NODAGA-galacto-BBN for the early prediction of RIPF. We prepared RIPF mice and acquired PET/CT images of [¹⁸F]F-FDG and [⁶⁴Cu]Cu-NODAGA-galacto-BBN at 0, 2, 5, and 11 weeks after irradiation (n = 3-10). We confirmed that [⁶⁴Cu]Cu-NODAGA-galacto-BBN targets GRPR in irradiated RAW 264.7 cells. In addition, we examined whether [⁶⁴Cu]Cu-NODAGA-galacto-BBN monitors the therapeutic efficacy in RIPF mice (n = 4). As a result, the lung uptake ratio (irradiated-to-normal) of [⁶⁴Cu]Cu-NODAGA-galacto-BBN was the highest at 2 weeks, followed by its decrease at 5 and 11 weeks after irradiation, which matched with the expression of GRPR and was more accurately predicted than [¹⁸F]F-FDG. These uptake results were also confirmed by the cell uptake assay. Furthermore, [⁶⁴Cu]Cu-NODAGA-galacto-BBN could monitor the therapeutic efficacy of pirfenidone in RIPF mice. We conclude that [⁶⁴Cu]Cu-NODAGA-galacto-BBN is a novel PET imaging probe for the early prediction of RIPF-targeting GRPR expressed during the inflammatory response.

The methodology to estimate the demand and supply of national psychiatric services in Taiwan from 2005 to 2030

BACKGROUND

The transformation from institutionalization to community-based mental healthcare may increase the difficulty of psychiatric workforce estimation and change the role of psychiatrists in hospitals and private clinics.

METHODS

This study aimed to estimate the growth and forecast psychiatric services in hospitals and private clinics in Taiwan from 2005 to 2030. We first examined the correlation between the number of psychiatrists and several indicators of psychiatric services. The forecast of the national demand for psychiatrists was based on projected outpatient psychiatrist visits from historical data. We also estimated the supply of psychiatrists by the number of psychiatrists practicing in hospitals or private clinics from Taiwan's Medical Affairs System and examined the supply and demand of the psychiatrist workforce through 2030.

RESULTS

Outpatient visit was the most relevant indicator of psychiatric services to psychiatrist workforce. Growth rates in private clinics were higher than the hospital counterparts within the following decade (172.3 % vs. 37.7 %) and in the following decade (42.3 % vs. 13.3 %). The hospital-clinic disparity in the growth of psychiatric services also reflects the shortage of psychiatrists in private clinics but not in hospitals through 2030. The supply of 1158 psychiatrists in hospitals would nearly equal the clinical-based demand of 1156 psychiatrists in 2030. By contrast, the supply of 514 psychiatrists in private clinics would be lower than the clinical-based demand of 636 psychiatrists in 2030.

CONCLUSION

The hospital-clinic disparity in the growth of psychiatric services reflects the transformation from hospital-based to community-based mental healthcare in Taiwan.

PARP-1 genetic polymorphism associated with radiation sensitivity of non-small cell lung cancer

About 70% of non-small cell lung cancer (NSCLC) patients require radiotherapy. However, due to the difference in radiation sensitivity, the treatment outcome may differ for the same pathology and choice of treatment. Poly (ADP-ribose) polymerase 1 (PARP-1) is a key gene responsible for DNA repair and is involved in base excision repair as well as repair of single strand break induced by ionizing radiation and oxidative damage. In order to investigate the relationship between PARP-1 gene polymorphism and radiation sensitivity in NSCLC, we collected 141 primary NSCLC patients undergoing three-dimensional conformal radiotherapy. For each case, the gross tumor volumes (GTV) before radiation and that after 40 Gy radiation were measured to calculate the tumor regression rate. TaqMan real-time polymerase chain reaction was performed to genotype the single-nucleotide polymorphisms (SNPs). Genotype frequencies for PARP-1 genotypes were 14.2% for C/C, 44.7% for C/G and 41.1% for G/G. The average tumor regression rate after 40 Gy radiation therapy was 35.1% ± 0.192. Tumor regression rate of mid-term RT of C/C genotype was 44.6% ± 0.170, which was higher than that of genotype C/G and G/G (32.4% ± 0.196 and 34.8% ± 0.188, respectively) with statistical significance (F = 3.169 p = 0.045). The higher tumor regression rate in patients with C/C genotype suggested that G allele was a protective factor against radiation therapy. Using the median tumor regression rate of 34%, we divided the entire cohort into two groups, and found that the frequency distribution of PARP-1 gene rs3219073 had significant difference between these two groups (p < 0.05). These results showed that PARP-1 gene polymorphism may affect patient radiation sensitivity and predict the efficacy of radiotherapy. It therefore presents an opportunity for developing new therapeutic targets to improve radiotherapy outcome.

An Overview of the Role of Radiotherapy in the Treatment of Small Cell Lung Cancer - A Mainstay of Treatment or a Modality in Decline?

AIMS

Small cell lung cancer (SCLC) accounts for about 15% of all lung cancers. Chemotherapy, immunotherapy and radiotherapy all play important roles in the management of SCLC. The aim of this study was to provide a comprehensive overview of the role and evidence of radiotherapy in the cure and palliation of SCLC.

MATERIALS AND METHODS

The search strategy included a search of the PubMed database, hand searches, reference lists of relevant review articles and relevant published abstracts.

CLINICALTRIALS

gov was also queried for relevant trials.

RESULTS

Thoracic radiotherapy improves overall survival in limited stage SCLC, but the timing and dose remain controversial. The role of thoracic radiotherapy in extensive stage SCLC with immunotherapy is the subject of several ongoing trials. Current evidence supports the use of prophylactic cranial irradiation (PCI) for limited stage SCLC but the evidence is equivocal in extensive stage SCLC. Whole brain radiotherapy is well established for the treatment of brain metastases but evidence is rapidly accumulating for the use of stereotactic radiosurgery. Further studies will define the role of PCI, whole brain radiotherapy and hippocampal avoidant PCI in the immunotherapy era.

CONCLUSION

Radiotherapy is an essential component in the multimodality management of SCLC. Technological advances have allowed safer delivery of radiotherapy with reduced toxicities. Discussion at multidisciplinary team meetings is important to ensure radiotherapy is considered and offered in appropriate patients.

Bayesian methods provide a practical real-world evidence framework for evaluating the impact of changes in radiotherapy

PURPOSE

Retrospective studies have identified a link between the average set-up error of lung cancer patients treated with image-guided radiotherapy (IGRT) and survival. The IGRT protocol was subsequently changed to reduce the action threshold. In this study, we use a Bayesian approach to evaluate the clinical impact of this change to practice using routine 'real-world' patient data.

METHODS AND MATERIALS

Two cohorts of NSCLC patients treated with IGRT were compared: pre-protocol change (N = 780, 5 mm action threshold) and post-protocol change (N = 411, 2 mm action threshold). Survival models were fitted to each cohort and changes in the hazard ratios (HR) associated with residual set-up errors was assessed. The influence of using an uninformative and a skeptical prior in the model was investigated.

RESULTS

Following the reduction of the action threshold, the HR for residual set-up error towards the heart was reduced by up to 10%. Median patient survival increased for patients with set-up errors towards the heart, and remained similar for patients with set-up errors away from the heart. Depending on the prior used, a residual hazard ratio may remain.

CONCLUSIONS

Our analysis found a reduced hazard of death and increased survival for patients with residual set-up errors towards versus away from the heart post-protocol change. This study demonstrates the value of a Bayesian approach in the assessment of technical changes in radiotherapy practice and supports the consideration of adopting this approach in further prospective evaluations of changes to clinical practice.

The mapping of mRNA alterations elucidates the etiology of radiation-induced pulmonary fibrosis

The etiology of radiation-induced pulmonary fibrosis is not clearly understood yet, and effective interventions are still lacking. This study aimed to identify genes responsive to irradiation and compare the genome expression between the normal lung tissues and irradiated ones, using a radiation-induced pulmonary fibrosis mouse model. We also aimed to map the mRNA alterations as a predictive model and a potential mode of intervention for radiation-induced pulmonary fibrosis. Thirty C57BL/6 mice were exposed to a single dose of 16 Gy or 20 Gy thoracic irradiation, to establish a mouse model of radiation-induced pulmonary fibrosis. Lung tissues were harvested at 3 and 6 months after irradiation, for histological identification. Global gene expression in lung tissues was assessed by RNA sequencing. Differentially expressed genes were identified and subjected to functional and pathway enrichment analysis. Immune cell infiltration was evaluated using the CIBERSORT software. Three months after irradiation, 317 mRNAs were upregulated and 254 mRNAs were downregulated significantly in the low-dose irradiation (16 Gy) group. In total, 203 mRNAs were upregulated and 149 were downregulated significantly in the high-dose irradiation (20 Gy) group. Six months after radiation, 651 mRNAs were upregulated and 131 were downregulated significantly in the low-dose irradiation group. A total of 106 mRNAs were upregulated and 4 downregulated significantly in the high-dose irradiation group. Several functions and pathways, including angiogenesis, epithelial cell proliferation, extracellular matrix, complement and coagulation cascades, cellular senescence, myeloid leukocyte activation, regulation of lymphocyte activation, mononuclear cell proliferation, immunoglobulin binding, and the TNF, NOD-like receptor, and HIF-1 signaling pathways were significantly enriched in the irradiation groups, based on the differentially expressed genes. Irradiation-responsive genes were identified. The differentially expressed genes were mainly associated with cellular metabolism, epithelial cell proliferation, cell injury, and immune cell activation and regulation.

Efficacy and safety of Xuebijing injection for radiation pneumonitis: A meta-analysis

Background

Currently, the treatment of radiation pneumonitis (RP) remains a clinical challenge. Although glucocorticoids are used for RP treatment, they have associated side effects. Xuebijing injection (XBJ) has been widely used for RP treatment in China, but so far no meta-analysis has evaluated its efficacy and safety.

Methods

PubMed, Cochrane Library, EMBASE, China National Knowledge Infrastructure, WANFANG database, SinoMED, and China Science and Technology J Database were searched for randomized controlled trials related to XBJ in RP treatment. Two researchers independently conducted literature screening, data extraction, and risk of bias assessment. The outcomes were synthesized and analyzed using the Cochrane Review Manager (RevMan 5.3) software, and a forest plot generated.

Result

Eight articles met the eligibility criteria for further data extraction and meta-analysis. A total of 578 patients with RP participated in these studies, including 296 in the experimental group (XBJ+BT), and 282 in the control group (BT). The results of the meta-analysis revealed that compared to the BT group, XBJ+BT significantly increased the total effective rate (n = 578; RR = 1.45, 95% CI: 1.30 to 1.61, p<0.0001), and IL-10 expression (n = 296; MD = 17.62, 95% CI:13.95 to 21.29, p<0.00001), decreased interleukin-6 (IL-6) expression (n = 296; MD = -21.56, 95% CI:-27.37 to -15.76, p<0.00001), that of tumor necrosis factor alpha (n = 246; MD = -25.63, 95% CI:-30.77 to -20.50, p<0.00001), and that of C-reactive protein (n = 296; MD = -48.61, 95% CI:-56.49–40.73, p< 0.00001).

Conclusion

Based on our results, we do not recommend XBJ as an adjuvant treatment for RP. Further randomized controlled trials with rigorous design, strict implementation, and standard reporting are needed to further evaluate the efficacy and safety of XBJ for RP treatment.

Systematic review registration

INPLASY registration number: INPLASY2020120037.

Effectiveness of Cytological Diagnosis with Outer Cannula Washing Solution for Computed Tomography-Guided Needle Biopsy

RATIONALE AND OBJECTIVES

We evaluated the availability of cytological diagnosis with outer cannula washing solution (C-OCWS) as a clinical diagnostic tool for computed tomography (CT)-guided needle biopsy.

MATERIALS AND METHODS

We retrospectively assessed 109 consecutive patients (71 males, 38 females; median age 68 years), who underwent CT-guided needle biopsy. In all patients, the specimens sampled by the inner needle were used for histological diagnosis, and those taken from the outer cannula were rinsed with 0.9% saline solution: outer cannula washing solution for cytological diagnosis. The accuracy of C-OCWS in addition to histological diagnosis were compared with that of histological diagnosis alone. We used binary logistic regression analysis to determine the variables associated with diagnostic accuracy for malignancy and lesion characteristics.

RESULTS

The C-OCWS method precisely diagnosed 7 (6.4%) malignant lesions (i.e., effective cases) in the 109 patients characterized as "negative for malignancy" via histological diagnosis alone. The accuracy of the combination of C-OCWS and histological diagnoses was significantly higher than that of histological diagnosis alone (0.95 vs. 0.89, respectively; p = 0.023). Multivariate logistic regression analysis showed that increasing only a marginal ratio (failure rate for proper position of biopsy needle within the tumor) was independently associated with a high rate of effective cases (p = 0.003).

CONCLUSION

C-OCWS may be helpful for improving the quality of CT-guided needle biopsy, and is a simple method that may not necessarily increase the patients' physical burden.

Efficacy and safety of recombinant human endostatin during peri-radiotherapy period in advanced non-small-cell lung cancer

Background: This study aimed to retrospectively investigate the efficacy and safety of recombinant human endostatin (Rh-endostatin) combined with radiotherapy in advanced non-small-cell lung cancer (NSCLC). Methods: Patients with unresectable stage III and IV NSCLC who treated with radiotherapy were enrolled. Patients who received Rh-endostatin infusion throughout the whole peri-radiotherapy period formed the Endostar group, and those who received no Rh-endostatin infusion were the control group. Results: The median progression-free survival was 8.0 and 4.4 months (hazard ratio: 0.53; 95% CI: 0.32-0.90; p = 0.019) and median overall survival was 40.0 and 13.1 months (hazard ratio: 0.53; 95% CI: 0.28-0.98; p = 0.045) for the Endostar and control groups, respectively. The Endostar group exhibited a numerically lower rate of radiation pneumonitis relapse, radiation pneumonitis death and pulmonary fibrosis. Conclusion: Rh-endostatin infusion throughout the peri-radiotherapy period enhanced radiosensitivity and showed better survival outcomes and a tendency toward fewer radiation-related pulmonary events in patients with NSCLC.

Higher Radiation Dose to the Immune Cells Correlates with Worse Tumor Control and Overall Survival in Patients with Stage III NSCLC: A Secondary Analysis of RTOG0617

Background: We hypothesized that the Effective radiation Dose to the Immune Cells (EDIC) in circulating blood is a significant factor for the treatment outcome in patients with locally advanced non-small-cell lung cancer (NSCLC). Methods: This is a secondary study of a phase III trial, NRG/RTOG 0617, in patients with stage III NSCLC treated with radiation-based treatment. The EDIC was computed as equivalent uniform dose to the entire blood based on radiation doses to all blood-containing organs, with consideration of blood flow and fractionation effect. The primary endpoint was overall survival (OS), and the secondary endpoints were progression-free survival (PFS) and local progression-free survival (LPFS). The EDIC-survival relationship was analyzed with consideration of clinical significant factors. Results: A total of 456 patients were eligible. The median EDIC values were 5.6 Gy (range, 2.1-12.2 Gy) and 6.3 Gy (2.1-11.6 Gy) for the low- and high-dose groups, respectively. The EDIC was significantly associated with OS (hazard ratio [HR] = 1.12, p = 0.005) and LPFS (HR = 1.09, p = 0.02) but PFS (HR = 1.05, p = 0.17) after adjustment for tumor dose, gross tumor volume and other factors. OS decreased with an increasing EDIC in a non-linear pattern: the two-year OS decreased first with a slope of 8%/Gy when the EDIC < 6 Gy, remained relatively unchanged when the EDIC was 6-8 Gy, and followed by a further reduction with a slope of 12%/Gy when the EDIC > 8 Gy. Conclusions: The EDIC is a significant independent risk factor for poor OS and LPFS in RTOG 0617 patients with stage III NSCLC, suggesting that radiation dose to circulating immune cells is critical for tumor control. Organ at risk for the immune system should be considered during RT plan.

Characteristics Assessment of Online YouTube Videos on Radiotherapy for Lung Cancer

Introduction

The internet has become a mainstay source of health information for cancer patients. Online patient education videos are common; however, there have been no studies examining the quality of publicly available videos on radiotherapy for lung cancer (one of the most common forms of cancer). To fill this knowledge gap, we aim to systematically map and objectively assess videos discussing radiotherapy for lung cancer on YouTube.

Methods

The terms “radiotherapy for lung cancer,” “radiation for lung cancer,” “radiation therapy for lung cancer,” and “radiation treatment for lung cancer” were searched on YouTube using a clear-cache browser. Results were sorted by relevance and the top 50 English-language results for each search were recorded. After removing duplicates, each video was assessed for length, Video Power Index (VPI, which is the product of a video’s average daily views and like and dislike ratio), source, content, comment moderation, and misinformation. Two raters were used to ensure consistency. Results were evaluated using descriptive and inferential statistics.

Results

A total of 88 unique videos resulted from the search. The median video length was 4 minutes and 5 seconds. The average VPI was 10.9 (95% CI: 1.5-20.4) and the median number of views was 954.5. All videos were published between July 8, 2009 and November 18, 2020. Of the videos, 44% were published within the past two years. A total of 61% of the videos were from the USA, 14% were from the UK, 6% from Australia, 5% each from Canada and India, and other countries make up the remaining 10%. Most of the videos were published by healthcare facilities (39%) and non-profit organizations (31%). Content-wise, 95% of videos contain information specific to lung cancer. A total of 46 videos (52%) were targeted toward patient education. Of which, 37 covered radiotherapy for lung cancer, 12 covered side effects for radiotherapy, and 11 covered both. The other 42 videos (48%) were designed for a professional audience. Stereotactic body radiation therapy (SBRT)/stereotactic ablative radiotherapy (SABR) was the most commonly described radiotherapy modality (42%), and the physician interview was the most common format, being used in 59% of videos. Out of the 38 videos with at least one comment, only two (5%) were moderated by the host channel. None of the videos featured misleading information.

Conclusions

This study comprehensively surveyed YouTube videos pertaining to radiotherapy for lung cancer to provide a high-level overview of the information that patients may find online. Although nearly half of the videos describe lung cancer radiotherapy for patients, only a small proportion comprehensively cover both radiotherapy and its side effects. The results of our study can help guide the development of patient education tools and encourage healthcare providers to recognize the limitations of online health information and proactively address patient questions regarding radiotherapy. Future research could examine videos on other lung cancer treatment options or radiotherapy for other cancers.

Feasibility of function-guided lung treatment planning with parametric response mapping

Purpose

Recent advancements in functional lung imaging have been developed to improve clinicians’ knowledge of patient pulmonary condition prior to treatment. Ultimately, it may be possible to employ these functional imaging modalities to tailor radiation treatment plans to optimize patient outcome and mitigate pulmonary complications. Parametric response mapping (PRM) is a computed tomography (CT)–based functional lung imaging method that utilizes a voxel‐wise image analysis technique to classify lung abnormality phenotypes, and has previously been shown to be effective at assessing lung complication risk in diagnostic applications. The purpose of this work was to demonstrate the implementation of PRM guidance in radiotherapy treatment planning.

Methods and materials

A retrospective study was performed with 18 lung cancer patients to test the incorporation of PRM into a radiotherapy planning workflow. Paired inspiration/expiration pretreatment CT scans were acquired and PRM analysis was utilized to classify each voxel as normal, parenchymal disease, small airway disease, and emphysema. Density maps were generated for each PRM classification to contour high density regions of pulmonary abnormalities. Conventional volumetric‐modulated arc therapy and PRM‐guided treatment plans were designed for each patient.

Results

PRM guidance was successfully implemented into the treatment planning process. The inclusion of PRM priorities resulted in statistically significant (p < 0.05) improvements to the V20Gy within the PRM avoidance contours. On average, reductions of 5.4% in the V20Gy(%) were found. The PRM‐guided treatment plans did not significantly increase the dose to the organs at risk or result in insufficient planning target volume coverage, but did increase plan complexity.

Conclusions

PRM guidance was successfully implemented into a treatment planning workflow and shown to be effective for dose redistribution within the lung. This work has provided a framework for the potential clinical implementation of PRM‐guided treatment planning.

Integrating Multiomics Information in Deep Learning Architectures for Joint Actuarial Outcome Prediction in Non-Small Cell Lung Cancer Patients After Radiation Therapy

PURPOSE

Novel actuarial deep learning neural network (ADNN) architectures are proposed for joint prediction of radiation therapy outcomes-radiation pneumonitis (RP) and local control (LC)-in stage III non-small cell lung cancer (NSCLC) patients. Unlike normal tissue complication probability/tumor control probability models that use dosimetric information solely, our proposed models consider complex interactions among multiomics information including positron emission tomography (PET) radiomics, cytokines, and miRNAs. Additional time-to-event information is also used in the actuarial prediction.

METHODS AND MATERIALS

Three architectures were investigated: ADNN-DVH considered dosimetric information only; ADNN-com integrated multiomics information; and ADNN-com-joint combined RP2 (RP grade ≥2) and LC prediction. In these architectures, differential dose-volume histograms (DVHs) were fed into 1D convolutional neural networks (CNN) for extracting reduced representations. Variational encoders were used to learn representations of imaging and biological data. Reduced representations were fed into Surv-Nets to predict time-to-event probabilities for RP2 and LC independently and jointly by incorporating time information into designated loss functions.

RESULTS

Models were evaluated on 117 retrospective patients and were independently tested on 25 newly accrued patients prospectively. A multi-institutional RTOG0617 data set of 327 patients was used for external validation. ADNN-DVH yielded cross-validated c-indexes (95% confidence intervals) of 0.660 (0.630-0.690) for RP2 prediction and 0.727 (0.700-0.753) for LC prediction, outperforming a generalized Lyman model for RP2 (0.613 [0.583-0.643]) and a generalized log-logistic model for LC (0.569 [0.545-0.594]). The independent internal test and external validation yielded similar results. ADNN-com achieved an even better performance than ADNN-DVH on both cross-validation and independent internal test. Furthermore, ADNN-com-joint, which yielded performance similar to ADNN-com, realized joint prediction with c-indexes of 0.705 (0.676-0.734) for RP2 and 0.740 (0.714-0.765) for LC and achieved an area under a free-response receiving operator characteristic curve (AU-FROC) of 0.729 (0.697-0.773) for the joint prediction of RP2 and LC.

CONCLUSION

Novel deep learning architectures that integrate multiomics information outperformed traditional normal tissue complication probability/tumor control probability models in actuarial prediction of RP2 and LC.

Mapping lung ventilation through stress maps derived from biomechanical models of the lung

PURPOSE

Most existing computed tomography (CT)-ventilation imaging techniques are based on deformable image registration (DIR) of different respiratory phases of a four-dimensonal CT (4DCT) scan of the lung, followed by the quantification of local breathing-induced changes in Hounsfield Units (HU) or volume. To date, only moderate correlations have been reported between these CT-ventilation metrics and standard ventilation imaging modalities for adaptive lung radiation therapy. This study evaluates the use of stress maps derived from biomechanical model-based DIR as an alternative CT-ventilation metric.

MATERIALS AND METHODS

Six patients treated for lung cancer with conventional radiation therapy were retrospectively analyzed. For each patient, a 4DCT scan and Tc-99m SPECT-V image acquired for treatment planning were collected. Biomechanical model-based DIR was applied between the inhale and exhale phase of the 4DCT scans and stress maps were calculated. The voxel-wise correlation between the reference SPECT-V image and map of the maximum principal stress was measured with a Spearman correlation coefficient. The overlap between high (above the 75th percentile) and low (below the 25th percentile) functioning volumes extracted from the reference SPECT-V and the stress maps was measured with Dice similarity coefficients (DSC). The results were compared to those obtained when using two classical CT-ventilation metrics: the change in HU and Jacobian determinant.

RESULTS

The mean Spearman correlation coefficients were: 0.37 ± 18 and 0.39 ± 13 and 0.59 ± 0.13 considering the changes in HU, Jacobian and maximum principal stress, respectively. The corresponding mean DSC coefficients were 0.38 ± 0.09, 0.37 ± 0.07 and 0.52 ± 0.07 for the high ventilation function volumes and 0.48 ± 0.13, 0.44 ± 0.09 and 0.52 ± 0.07 for the low ventilation function volumes.

CONCLUSION

For presenting a significantly stronger and more consistent correlation with standard SPECT-V images than previously proposed CT-ventilation metrics, stress maps derived with the proposed method appear to be a promising tool for incorporation into functional lung avoidance strategies.

Efficacy of erlotinib as first-line maintenance therapy in patients with locally advanced or metastatic nonsmall cell lung cancer who have not experienced disease progression or unacceptable toxicity during chemotherapy

Background:

First-line maintenance with erlotinib in nonsmall cell lung cancer (NSCLC) patients without progression after four cycles of chemotherapy was well tolerated and significantly prolonged progression-free survival (PFS) compared with placebo.

Aim and Design:

This open-label, single arm, Phase IV, interventional study was designed to evaluate erlotinib as first-line maintenance after chemotherapy in Indian NSCLC patients. Primary efficacy objective was to evaluate PFS rate (PFSR) at week 52 and secondary objectives were determination of PFS, overall survival (OS), overall response rate (ORR), disease control rate, and safety.

Subjects and Methods:

Patients were treated with erlotinib until disease progression/death/unacceptable toxicity or end of study. Patients with disease progression underwent scheduled clinical assessments every 12 weeks thereafter. Kaplan–Meier estimates were used to evaluate PFSR, PFS, and OS. The ORR was summarized using number and percentage along with two-sided 95% Clopper–Pearson confidence interval. The incidence of adverse events (AEs) and serious AEs (SAEs) was tabulated according to severity, outcome, and relationship to erlotinib.

Results:

Of the 51 enrolled patients, 47 patients completed the study (2: Continuing treatment, 41: Disease progression, and 4: Death) and four patients discontinued treatment (3: Lost to follow-up; 1: Withdrew consent). PFSR was 22.5% at 12 months, median PFS 99 days (14.14 weeks), and median OS was 671 days (22 months). The probability of OS was 74.5% at 14 months. The ORR was 25.5%, and disease control rate was 55.3%. AEs were reported in 62.7% and SAE in 7.8% of patients. Common AEs were diarrhea and rash.

Conclusions:

Erlotinib was well tolerated by Indian patients in first-line maintenance setting and resulted in median PFS of 14 weeks and median OS of 22 months better than previously reported and with no new safety concerns in this population.

The role of the gut microbiome on radiation therapy efficacy and gastrointestinal complications: A systematic review

Radiation therapy (RT) is an essential component of therapy either curative or palliative armamentarium in oncology, but its efficacy varies considerably among patients through many extrinsic and intrinsic mechanisms of the tumour, which are beginning to be better understood. Recent studies have shown that the gut microbiome represents a key factor in the modulation of the systemic immune response and consequently on patients' outcome. Moreover, the emergence of biomarkers that are derived from the gut microbiota has fuelled the development of adjuvant strategies for patients treated with immunotherapy in combination or not with RT. Despite progress in development of more precise radiotherapy techniques, almost all patients undergoing RT to the abdomen, pelvis, or rectum develop acute adverse events as a consequence of several dose-limiting parameters such as the location of irradiation that may subsequently damage normal tissue including the intestinal epithelium. Several lines of evidence in preclinical models identified that vancomycin improves RT-induced gastrointestinal toxicities such as diarrhea and oral mucositis. In order to gain further insight into this rapidly evolving field, we have systematically reviewed the studies that have described how the gut microbiome may directly or indirectly modulate RT efficacy and its gastro-intestinal toxicities. Lastly, we outline current knowledge gaps and discuss potentially more satisfactory therapeutic options to restore the functionality of the gut microbiome of patients treated with RT.

The radiotherapy utilization rate in pediatric tumors: An analysis of 13,305 patients

PURPOSE

Although the radiotherapy utilization rate (RUR) is determined for most adult cancers, it is seldom reported in childhood tumors, particularly in low- and middle-income countries (LMIC) where the majority of pediatric cancer patients reside. This study aims to investigate the real-life RUR for pediatric tumors in a large LMIC center.

MATERIALS AND METHODS

The electronic files of patients treated at a single institution during 2010-2017 were reviewed and the RUR was defined as the percentage of patients who received at least one radiotherapy (RT) course from the total number of patients.

RESULTS

A total of 4390 out of 13,305 pediatric cancer patients received at least one RT course with a RUR of 33%. The curative, salvage, and palliative RURs were 27.8%, 2%, and 5.7%, respectively. There was a considerable variation in the RUR between various tumors, ranging from 0% in choroid plexus papilloma and other rare tumors to 100% in intracranial germinoma. Moreover, the RUR varied among different stages within each tumor type. Overall, 753 patients received 920 palliative RT courses (range 1-9) at a median dose of 30 Gy. The most commonly irradiated metastatic sites were the bone (34%) and the brain (9.8%).

CONCLUSION

This is the first analysis to provide valuable insights into the RUR for childhood tumors. Together with population-based pediatric cancer registries, this will help decipher pediatric RT needs and deficits. Additionally, the underutilization of palliative RT calls for multidisciplinary palliative care provision for pediatric cancer patients.

Pharmacologic Inhibition of HIF-1α Attenuates Radiation-Induced Pulmonary Fibrosis in a Preclinical Image Guided Radiation Therapy

PURPOSE

Radiation-induced pulmonary fibrosis (RIPF) is a long-term side effect of thoracic radiation therapy. Hypoxia-induced vascular endothelial mesenchymal transition (EndMT) can occur during the development of RIPF. Here, we examined the direct contribution of endothelial HIF-1α (EC-HIF1α) on RIPF.

METHODS AND MATERIALS

An inducible Cre-lox-mediated endothelial Hif1a deletion mouse line was used to evaluate the potential of HIF-1α inhibition to suppress RIPF. To evaluate the effects of a pharmacologic HIF-1α inhibitor on RIPF after image guided radiation therapy (IGRT) for spontaneous lung adenocarcinoma, we generated conditional tdTomato; K-Ras^G12D; and p53 ^flox/flox mice to facilitate tracking of tumor cells expressing tdTomato.

RESULTS

We found that vascular endothelial-specific HIF-1α deletion shortly before radiation therapy inhibited the progression of RIPF along with reduced EndMT, whereas prolonged deletion of endothelial HIF-1α before irradiation did not. Moreover, we revealed that postirradiation treatment with the novel HIF-1α inhibitor, 2-methoxyestradiol (2-ME) could efficiently inhibit RIPF and EndMT. In addition, IGRT using primary mouse models of non-small cell lung cancer showed that combined treatment of 2-ME with ablative high-dose radiation therapy efficiently inhibited RIPF and the growth of both multifocal and single tumors, concomitantly reducing radiation-induced EndMT of normal as well as tumor regions.

CONCLUSION

These results suggest that a negative regulator of HIF-1α-mediated EndMT, such as 2-ME, may serve as a promising inhibitor of RIPF in radiation therapy.

Central Airway Toxicity After High Dose Radiation: A Combined Analysis of Prospective Clinical Trials for Non-Small Cell Lung Cancer

PURPOSE

To study the dosimetric risk factors for radiation-induced proximal bronchial tree (PBT) toxicity in patients treated with radiation therapy for non-small cell lung cancer (NSCLC).

METHODS AND MATERIALS

Patients with medically inoperable or unresectable NSCLC treated with conventionally fractionated 3-dimensional conformal radiation therapy (3DCRT) in prospective clinical trials were eligible for this study. Proximal bronchial tree (PBT) and PBT wall were contoured consistently per RTOG 1106 OAR-Atlas. The dose-volume histograms (DVHs) of physical prescription dose (DVHp) and biological effective dose (α/β = 2.5; DVH2.5) were generated, respectively. The primary endpoint was PBT toxicities, defined by CTCAE 4.0 under the terminology of bronchial stricture/atelectasis.

RESULTS

Of 100 patients enrolled, with a median follow-up of 64 months (95% confidence interval [CI], 50-78), 73% received 70 Gy or greater and 17% developed PBT toxicity (grade 1, 8%; grade 2, 6%; grade 3, 0%; and grade 4, 3%). The median time interval between RT initiation and onset of PBT toxicity was 8.4 months (95% CI, 4.7-44.1). The combined DVHs showed that no patient with a PBT maximum physical dose <65 Gy developed any PBT toxicity. Cox proportional hazards analysis and receiver operating characteristic analysis demonstrated that V75 of PBT was the most significant dosimetric parameter for both grade 1+ (P = .035) and grade 2+ (P = .037) PBT toxicities. The dosimetric thresholds for V75 of PBT were 6.8% and 11.9% for grade 1+ and grade 2+ PBT toxicity, respectively.

CONCLUSIONS

V75 of PBT appeared be the most significant dosimetric parameter for PBT toxicity after conventionally fractionated thoracic 3DCRT. Constraining V75 of PBT can limit clinically significant PBT toxicity.

Metachronous NSCLC in previously irradiated patients: is re-irradiation with SBRT a good option as definitive treatment?

Aim:

Treatment of metachronous second primary non-small cell lung cancer (NSCLC) in patients already treated with definitive radiotherapy is a matter of debate, since most patients are excluded from surgical treatment, which remains a therapeutic standard for patients with isolated lung masses. Salvage chemotherapy or immunotherapy alone offers a low probability of disease control. The option of re-irradiation often remains the only viable, but the risks of severe acute or late toxicities affecting the surrounding normal tissues make this a real clinical challenge.

Materials and methods:

From January 2015 to April 2018, five patients (male/female: 4/1; age 54–81 years, median 68) with previously irradiated NSCLC presented with a second primary lung tumour.

Results:

A partial response was seen in four patients, one complete responses in the fifth. The toxicity was low: two patients experienced a grade 2 asymptomatic radiation pneumonitis after 6 and 12 months from the end of stereotactic body radiation therapy, resolved with cortisone therapy. No acute or late oesophageal or cardiac toxicity was found.

Findings:

In this work, we present our initial experience about the use of stereotactic radiotherapy technique in already irradiated patients. We reported a local disease control in all cases with an acceptable toxicity.

Fluzoparib increases radiation sensitivity of non-small cell lung cancer (NSCLC) cells without BRCA1/2 mutation, a novel PARP1 inhibitor undergoing clinical trials

PROPOSE

Poly (ADP-ribose) polymerase 1 inhibitors were originally investigated as anti-cancer therapeutics with BRCA1/2 genes mutation. Here, we investigate the effectiveness of a novel PARP1 inhibitor fluzoparib, for enhancing the radiation sensitivity of NSCLC cells lacking BRCA1/2 mutation.

METHODS

We used MTS assays, western blotting, colony formation assays, immunofluorescence staining, and flow cytometry to evaluate the radiosensitization of NSCLC cells to fluzoparib and explore the underlying mechanisms in vitro. Through BRCA1 and RAD50 genes knockdown, we established dysfunctional homologous recombination (HR) DNA repair pathway models in NSCLC cells. We next investigated the radiosensitization effect of fluzoparib in vivo using human NSCLC xenograft models in mice. The expression of PARP1 and BRCA1 in human NSCLC tumor samples was measured by immunohistochemistry. Furthermore, we sequenced HR-related gene mutations and analyzed their frequencies in advanced NSCLC.

RESULTS

In vitro experiments in NSCLC cell lines along with in vivo experiments using an NSCLC xenograft mouse model demonstrated the radiosensitization effect of fluzoparib. The underlying mechanisms involved increased apoptosis, cell-cycle arrest, enhanced irradiation-induced DNA damage, and delayed DNA-damage repair. Immunohistochemical staining showed no correlation between the expression of PARP1 and BRCA1. Moreover, our sequencing results revealed high mutation frequencies for the BRCA1/2, CHEK2, ATR, and RAD50 genes.

CONCLUSION

The potential therapeutic value of fluzoparib for increasing the radiation sensitivity of NSCLC is well confirmed. Moreover, our findings of high mutation frequencies among HR genes suggest that PARP1 inhibition may be an effective treatment strategy for advanced non-small cell lung cancer patients.

A Small Compound KJ-28d Enhances the Sensitivity of Non-Small Cell Lung Cancer to Radio- and Chemotherapy

We previously reported on a poly (ADP-ribose) polymerase (PARP) 1/2 inhibitor N-(3-(hydroxycarbamoyl)phenyl)carboxamide (designated KJ-28d), which increased the death of human ovarian cancer BRCA1-deficient SNU-251 cells. In the present study, we further investigated the antitumor activities of KJ-28d in BRCA-proficient non-small cell lung cancer (NSCLC) cells to expand the use of PARP inhibitors. KJ-28d significantly inhibited the growth of NSCLC cells in vitro and in vivo, and induced DNA damage and reactive oxygen species in A549 and H1299 cells. Combined treatment with KJ-28d and ionizing radiation led to increased DNA damage responses in A549 and H1299 cells compared to KJ-28d or ionizing radiation alone, resulting in apoptotic cell death. Moreover, the combination of KJ-28d plus a DNA-damaging therapeutic agent (carboplatin, cisplatin, paclitaxel, or doxorubicin) synergistically inhibited cell proliferation, compared to either drug alone. Taken together, the findings demonstrate the potential of KJ-28d as an effective anti-cancer therapeutic agent for BRCA-deficient and -proficient cancer cells. KJ-28d might have potential as an adjuvant when used in combination with radiotherapy or DNA-damaging agents, pending further investigations.

What is the optimal radiotherapy utilization rate for lung cancer?-a systematic review

Lung cancer is a major cause of morbidity and mortality globally. Although radiotherapy (RT) may be beneficial in the radical and/or palliative management of many lung cancer patients, it is underutilized worldwide. Population-level development of RT resources requires estimates of optimal radiotherapy utilization rates (ORUR) and actual radiotherapy utilization rate (ARUR). A systematic review of PubMed database for English-language articles from January 2009 to January 2019 was performed. Keywords included utilization, underutilization, demand, epidemiologic, benchmark, RT and cancer. Data abstracted included: study population, diagnosis, stage, year of diagnosis, timing of RT, intent of RT, ARUR, and ORUR. Eligible studies provided ARUR or ORUR for lung cancer, small cell lung cancer (SCLC), or non-small cell lung cancer (NSCLC). Included ARUR were based on at least 1,000 patients who were diagnosed or treated in 2009 or later. Included ORUR were based on evidence review or ARUR in 2009 or later. The initial search strategy yielded 1,627 unique abstracts. After review, 105 articles were determined appropriate for full-text review. From these, a final set of 21 articles met all inclusion criteria. In eight papers, ORUR was estimated. Estimated lifetime ORUR ranged from 61% to 82%. Methods for estimation included the evidence-based guideline model, Malthus model, and criterion-based benchmarking (CBB) model. The majority of estimates (6/8) used the evidence-based guideline model. Fifteen papers provided ARUR on lung cancer, inclusive of SCLC and NSCLC. ARUR within 9 months to 1 year of diagnosis ranged from 39% to 46%. Lifetime ARUR was an estimated 52% in Ontario, Canada. Palliative intent ARUR ranged from 12% in Central Poland to 46% in Ontario, Canada. RT is underutilized for lung cancer globally, and there is wide geographical variation in the level of underutilization.

Comparison of predictive powers of functional and anatomic dosimetric parameters for radiation-induced lung toxicity in locally advanced non-small cell lung cancer

PURPOSE

To investigate the predictive value of the perfusion (Q) single-photon emission computed tomography (SPECT)-weighted dose-function histogram (DFH) obtained mid-treatment (mid-Tx) with radiotherapy (RT) for radiation-induced lung toxicity (RILT) in patients with non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

The study population consisted of NSCLC patients who were undergoing RT treatment and enrolled in prospective imaging studies. Q-SPECT was performed prior to and during RT (at ∼40-45 Gy). A baseline dose-volume histogram (DVH) and mid-Tx DVH based on simulation CT as well as a baseline DFH and mid-Tx DFH based on Q-SPECT were calculated. Only patients with stage III NSCLC and visible functional lung (FL) changes on the mid-Tx scan were eligible for this enriched analysis. RILT was graded according to a reported scale.

RESULTS

Forty-two stage III NSCLC patients met the criteria for inclusion. The accumulative incidence of grade ≥2 RILT was 31% in this high-risk population. Significant differences in functional metrics such as functional lung volume FV5-FV20 at increments of 5 Gy and functional MLD (FMLD) were observed between patients with and without grade ≥2 RILT (p < 0.05). Similar results were also obtained for anatomical metrics from V5-V20 and MLD (p < 0.05). The areas under the receiver operating characteristic curves (AUCs) ranged from 0.724to 0.812 for baseline DVH parameters, from 0.745 to 0.830 for mid-Tx DVH parameters, from 0.764 to 0.878 for baseline DFH parameters, and from 0.767 to 0.891 for mid-Tx DFH parameters. Further principal components analysis showed that the AUCs were 0.814/0.817 and 0.790/0.857 for baseline/mid-Tx DVH and baseline/mid-Tx DFH, respectively.

CONCLUSIONS

Mid-Tx DFH parameters based on Q-SPECT were significantly elevated in patients with grade ≥2 RILT in this study population. Among the metrics compared, mid-Tx DFH seemed to have better predictive accuracy, but this difference did not reach statistical difference.

Real-world data: towards achieving the achievable in cancer care

The use of data from the real world to address clinical and policy-relevant questions that cannot be answered using data from clinical trials is garnering increased interest. Indeed, data from cancer registries and linked treatment records can provide unique insights into patients, treatments and outcomes in routine oncology practice. In this Review, we explore the quality of real-world data (RWD), provide a framework for the use of RWD and draw attention to the methodological pitfalls inherent to using RWD in studies of comparative effectiveness. Randomized controlled trials and RWD remain complementary forms of medical evidence; studies using RWD should not be used as substitutes for clinical trials. The comparison of outcomes between nonrandomized groups of patients who have received different treatments in routine practice remains problematic. Accordingly, comparative effectiveness studies need to be designed and interpreted very carefully. With due diligence, RWD can be used to identify and close gaps in health care, offering the potential for short-term improvement in health-care systems by enabling them to achieve the achievable.

Comparison of Methods for Measuring Radiotherapy Utilisation

AIMS

Evidence-based estimates of appropriate rates of radiotherapy utilisation are usually stated as the proportion of cancer patients who should receive radiotherapy at least once in their lifetime. However, the prolonged follow-up required to measure the lifetime radiotherapy rate limits its value in monitoring access to radiotherapy in routine practice. The objectives of this study were to evaluate shorter-term methods for measuring radiotherapy utilisation and to determine how well they predict the lifetime radiotherapy rate.

MATERIALS AND METHODS

The Ontario Cancer Registry provided records of all cases of cancer diagnosed in Ontario between 1984 and 2015. Records of all radiotherapy delivered by Ontario cancer centres were linked to individual cases in the Ontario Cancer Registry. Patients were followed forward for 20 years to determine the relationship between short-term and long-term rates of use of radiotherapy. Radiotherapy utilisation was also estimated by comparing total radiotherapy workload with cancer incidence; these measures were compared with observed long-term radiotherapy rates.

RESULTS

The rate of use of radiotherapy within 1 year of diagnosis (RT_1y) was strongly predictive of the rate of use of radiotherapy after 20 years (RT_20y); for each annual cohort of cases between 1984 and 1995, RT_20y was approximately equal to 1.3 × RT_1y. The number of cases treated for the first time with radiotherapy in a specified period, divided by the number of new cases diagnosed in the same period, was about equal to the proportion of cases treated with radiotherapy within 20 years of diagnosis (RT_20y).

CONCLUSIONS

The lifetime rate of use of radiotherapy may be predicted quite accurately from the rate observed within 1 year of diagnosis, or from the ratio of new cases treated to cancer incidence in a specified period. Either of these measures may therefore be used to audit radiotherapy utilisation against the existing evidence-based targets.

Genetic variants of SP-D confer susceptibility to radiation pneumonitis in lung cancer patients undergoing thoracic radiation therapy

Background

Surfactant protein D (SP‐D) is an innate immunity molecule in the alveoli. However, the associations between genetic variants of SP‐D and radiation pneumonitis (RP) have never been investigated.

Methods

The Linkage disequilibrium of SP‐D and tagSNPs were analyzed by using Haploview 4.1. Eight tagSNPs were genotyped among 396 lung cancer patients who received thoracic radiation therapy with follow–up time (median [P25, P75]: 11[6, 18]) using improved multiplex ligation detection reaction (iMLDR). The associations between clinical characteristics, tagSNP alleles, genotypes, haplotypes and onset time of grade ≥2 or ≥3 RP were evaluated by using univariate and multivariate Cox proportional hazard regression model.

Results

Three tagSNPs of SP‐D (rs1998374, rs911887 and rs2255326) were significantly associated with grade ≥2 RP in multivariate analysis with multiple testing (Q test). The rs199874 had a protective effect for grade ≥2 RP in the dominant model (Hazard ratio (HR), 0.575; 95% confidence interval (CI), 0.378‐0.875). The homozygous mutant genotype for rs911887 had risk effect for grade ≥2 RP (HR, 2.209; 95% CI, 1.251‐3.902). The A mutant allele of rs2255326 also showed an elevated risk for grade ≥2 RP (HR, 1.777; 95% CI, 1.283‐2.461) and this risk effect was still significant in the recessive genetic model (HR, 3.320; 95% CI, 1.659‐6.644) and dominant genetic model (HR, 1.773; 95% CI, 1.166‐2.696). Compared to the lung cancer patients bearing the most common haplotype C‐G‐T, the patients bearing the haplotype T‐A‐C (rs1998374‐rs2255326‐rs911887) showed a significant risk of both grade ≥2 RP (HR, 1.885; 95% CI, 1.284‐2.765) and grade ≥3 RP (HR, 2.256; 95% CI, 1.248‐4.080).

Conclusions

Genetic variants of SP‐D were associated with risk of RP development in lung cancer patients receiving thoracic radiotherapy.

Modern Radiation Further Improves Survival in Non-Small Cell Lung Cancer: An Analysis of 288,670 Patients

Background: Radiation therapy plays an increasingly important role in the treatment of patients with non-small-cell lung cancer (NSCLC). The purpose of the present study is to assess the survival outcomes of radiotherapy treatment compared to other treatment modalities and to determine the potential role of advanced technologies in radiotherapy on improving survival. Methods: We used cancer incidence and survival data from the Surveillance, Epidemiology, and End Results database linked to U.S. Census data to compare survival outcomes of 288,670 patients with stage I-IV NSCLC treated between 1999 and 2008. The primary endpoint was overall survival. Results: Among the 288,670 patients diagnosed with stage I-IV NSCLC, 92,374 (32%) patients received radiotherapy-almost double the number receiving surgery (51,961, 18%). Compared to other treatment groups and across all stages of NSCLC, patients treated with radiotherapy showed greater median and overall survival than patients without radiation treatment (p < 0.0001). Radiotherapy had effectively improved overall survival regardless of age, gender, and histological categorization. Radiotherapy treatment received during the recent time period 2004 - 2008 is correlated with enhanced survival compared to the earlier time period 1999 - 2003. Conclusion: Radiation therapy was correlated with increased overall survival for all patients with primary NSCLC across stages. Combined surgery and radiotherapy treatment also correlates with improved survival, signaling the value of bimodal or multimodal treatments. Population-based increases in overall survival were seen in the recent time period, suggesting the potential role of advanced radiotherapeutic technologies in enhancing survival outcomes for lung cancer patients.

Advances in Molecular Mechanisms and Treatment of Radiation-Induced Pulmonary Fibrosis

Radiation-induced pulmonary fibrosis (RIPF) is a common complication in patients with lung cancer and breast cancer after receiving thoracic radiotherapy. The average incidence of RIPF is 16%-28% after radiotherapy. RIPF includes a heterogeneous group of lung disorders characterized by progressive and irreversible destruction of lung architecture and disruption of gas exchange. The clinical signs of RIPF include increasing dyspnea, deteriorating lung function, and accumulation of interstitial fluid, eventually leading to respiratory failure. No medical therapy for RIPF has been approved for routine clinical use despite the apparent need for an effective treatment. Numerous signaling pathways are involved in the initiation and progression of RIPF. Also, various approaches for RIPF treatments have focused on several aspects of the current understanding of the molecular pathology of RIPF. This review used the mechanistic categories of associated cell signaling pathways, epithelial cell dysfunction and senescence, abnormal lung remodeling, and aberrant innate and adaptive immunity to review the published literature on RIPF to date and then to identify potential areas for the effective treatment of RIPF.

α-PD-L1 mAb enhances the abscopal effect of hypo-fractionated radiation by attenuating PD-L1 expression and inducing CD8+ T-cell infiltration

AIM

We investigated a promising cooperative combination of radiotherapy (RT) and programmed death ligand 1 (PD-L1) monoclonal antibodies (mAb) in both local and abscopal tumors.

MATERIALS & METHODS

C57BL/6 mice were randomly grouped and received RT, α-PD-L1 mAb or combination therapy 13 days after implantation of Lewis lung carcinoma cells. Flow cytometry and immunohistochemistry analyses demonstrated CD8⁺ T-cell infiltration and PD-L1 expression in tumor issue. Cytometric bead arrays were used to examine cytokine levels.

RESULTS

Our studies revealed that administration of 8 Gy × 3 F with α-PD-L1 mAb promoted both local and distant control. Only local hypofractionated RT enhanced CD8⁺ T-cell infiltration with increased PD-L1 expression at distant foci, which might occur via serum IFN-γ modulation. Addition of α-PD-L1 mAb reduced PD-L1 expression and further increased CD8⁺ T-cell infiltration.

CONCLUSION

We identified a novel mechanism through which combination therapy enhanced the abscopal effect.

Radiation-induced lung injury: impact on macrophage dysregulation and lipid alteration - a review

Lung cancer continues to be the leading cause of cancer deaths and more than one million lung cancer patients will die every year worldwide. Radiotherapy (RT) plays an important role in lung cancer treatment, but the side effects of RT are pneumonitis and pulmonary fibrosis. RT-induced lung injury causes damage to alveolar-epithelial cells and vascular endothelial cells. Macrophages play an important role in the development of pulmonary fibrosis despite its role in immune response. These injury activated macrophages develop into classically activated M1 macrophage or alternative activated M2 macrophage. It secretes cytokines, interleukins, interferons, and nitric oxide. Several pro-inflammatory lipids and pro-apoptotic proteins cause lipotoxicity such as LDL, FC, DAG, and FFA. The overall findings in this review conclude the importance of macrophages in inducing toxic/inflammatory effects during RT of lung cancer, which is clinically vital to treat the radiation-induced fibrosis.

Doses of radiation to the pericardium, instead of heart, are significant for survival in patients with non-small cell lung cancer

BACKGROUND AND PURPOSE

Higher cardiac dose was associated with worse overall survival in the RTOG0617 study. Pericardial effusion (PCE) is a common cardiac complication of thoracic radiation therapy (RT). We investigated whether doses of radiation to the heart and pericardium are associated with PCE and overall survival in patients treated with thoracic radiation for non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

A total of 94 patients with medically inoperable/unresectable NSCLC treated with definitive RT in prospective studies were reviewed for this secondary analysis. Heart and pericardium were contoured consistently according to the RTOG1106 Atlas, with the great vessels and thymus of the upper mediastinal structures included in the upper part of pericardium, only heart chambers included in the heart structure. Clinical factors and dose-volume parameters associated with PCE or survival were identified via Cox proportional hazards modeling. The risk of PCE and death were mapped using DVH atlases.

RESULTS

Median follow-up for surviving patients was 58 months. The overall rate of PCE was 40.4%. On multivariable analysis, dosimetric factors of heart and pericardium were significantly associated with the risk of PCE. Pericardial V30 and V55 were significantly correlated with overall survival, but presence of PCE and heart dosimetric factors were not.

CONCLUSION

PCE was associated with both heart and pericardial doses. The significance of pericardial dosimetric parameters, but not heart chamber parameters, on survival suggests the potential significance of radiation damage to the cranial region of pericardium.

Anticancer therapy and lung injury: molecular mechanisms

INTRODUCTION

Chemotherapy and radiation therapy are two mainstream strategies applied in the treatment of cancer that is not operable. Patients with hematological or solid tumor malignancies substantially benefit from chemotherapeutic drugs and/or ionizing radiation delivered to the site of malignancy. However, considerable adverse effects, including lung inflammation and fibrosis, are associated with the use of these treatment modalities. Areas covered: As we move toward the era of precision health, we are compelled to understand the molecular basis of chemoradiation-induced pathological lung remodeling and to develop effective treatment strategies that mitigate the development of chronic lung disease (i.e. fibrosis) in cancer patients. The review discusses chemotherapeutic agents that are reported to induce or associate with acute and/or chronic lung injury. Expert commentary: There is a need to molecularly understand how chemotherapeutic drugs induce or associate with respiratory toxicities and whether such characteristics are inherently related to their antitumor effect or are collateral. Once such mechanisms have been identified and/or fully characterized, they may be able to guide disease-management decisions including effective intervention strategies for the adverse effects. In the meantime, radiation oncologists should be judicious on the dose of radiation delivered to the lungs, the volume of lung irradiated, and concurrent use of chemotherapeutic drugs.

Oridonin Enhances Radiation-Induced Cell Death by Promoting DNA Damage in Non-Small Cell Lung Cancer Cells

Although many attempts have been made to improve the efficacy of radiotherapy to treat cancer, radiation resistance is still an obstacle in lung cancer treatment. Oridonin is a natural compound with promising antitumor efficacy that can trigger cancer cell death; however, its direct cellular targets, efficacy as a radiosensitizer, and underlying mechanisms of activity remain unclear. Herein, we report that oridonin exhibits additive cytotoxic and antitumor activity with radiation using the H460 non-small cell lung cancer cell lines. We assessed the effect of oridonin by proliferation, clonogenic, reactive oxygen species (ROS) production, DNA damage, and apoptosis assays. In vitro, oridonin enhanced the radiation-induced inhibition of cell growth and clonogenic survival. Oridonin also facilitated radiation-induced ROS production and DNA damage and enhanced apoptotic cell death. In vivo, the combination of oridonin and radiation effectively inhibited H460 xenograft tumor growth, with higher caspase-3 activation and H2A histone family member X (H2AX) phosphorylation compared with that of radiation alone. Our findings suggest that oridonin possesses a novel mechanism to enhance radiation therapeutic responses by increasing DNA damage and apoptosis. In conclusion, oridonin may be a novel small molecule to improve radiotherapy in non-small cell lung cancer.

Moving targets in 4D-CTs versus MIP and AIP: comparison of patients data to phantom data

Purpose

Maximum (MIP) and average intensity projection (AIP) CTs allow rapid definition of internal target volumes in a 4D-CT. The purpose of this study was to assess the accuracy of these techniques in a large patient cohort in combination with simulations on a lung phantom.

Methods

4DCT data from a self-developed 3D lung phantom and from 50 patients with lung tumors were analyzed. ITVs were contoured in maximum (ITV_MIP) and average intensity projection (ITV_AIP) and subsequently compared to ITVs contoured in 10 phases of a 4D-CT (ITV₁₀). In the phantom study additionally a theoretical target volume was calculated for each motion and compared to the contoured volumes.

Results

ITV₁₀ overestimated the actual target volume by 9.5% whereas ITV_MIP and ITV_AIP lead to an underestimation of − 1.8% and − 11.4% in the phantom study. The ITV_MIP (ITV_AIP) was in average − 10.0% (− 18.7%) smaller compared to the ITV₁₀. In the patient CTs deviations between ITV₁₀ and MIP/AIP were significantly larger (MIP: – 20.2% AIP: -33.7%) compared to this. Tumors adjacent to the chestwall, the mediastinum or the diaphragm showed lower conformity between ITV₁₀ and ITV_MIP (ITV_AIP) compared to tumors solely surrounded by lung tissue. Large tumor diameters (> 3.5 cm) and large motion amplitudes (> 1 cm) were associated with lower conformity between intensity projection CTs and ITV₁₀₋.

Conclusion

The application of MIP and AIP in the clinical practice should not be a standard procedure for every patient, since relevant underestimation of tumor volumes may occur. This is especially true if the tumor borders the mediastinum, the chest wall or the diaphragm and if tumors show a large motion amplitude.

Estimating the need for palliative radiotherapy for non-small cell lung cancer: A criterion-based benchmarking approach

BACKGROUND AND PURPOSE

Estimates of appropriate treatment rates are required for monitoring and improving access to cancer care. Optimal utilization rates for palliative radiotherapy (PRT) for patients with non-small cell lung cancer (NSCLC) remain undefined. We aim to estimate the appropriate PRT rate for the general NSCLC population.

MATERIALS AND METHODS

Ontario's population-based cancer registry identified patients with NSCLC who died of their disease between 2006 and 2010. Multivariate analysis identified factors affecting PRT use, enabling us to define a benchmark population with unimpeded access to PRT. Proportion of cases treated in the last 2 years of life (PRT_2y) was standardized to overall population characteristics. Benchmarks were compared to province-wide PRT_2y rates.

RESULTS

Availability of RT at the diagnosing hospital was the dominant determinant of increased PRT utilization. Patients diagnosed at hospitals with on site RT were therefore designated the benchmark population. The standardized benchmark for PRT_2y was 56%, compared to the province-wide rate of 49%. The gap between actual and optimal rates varied across patient ages, treatment indications, and geographic regions.

CONCLUSIONS

Approximately 56% of patients who die of NSCLC in Ontario need PRT, but many are never treated.

Radiotherapy utilization in developing countries: An IAEA study

BACKGROUND

The planning of national radiotherapy (RT) services requires a thorough knowledge of the country's cancer epidemiology profile, the radiotherapy utilization (RTU) rates and a future projection of these data. Previous studies have established RTU rates in high-income countries.

METHODS

Optimal RTU (oRTU) rates were determined for nine middle-income countries, following the epidemiological evidence-based method. The actual RTU (aRTU) rates were calculated dividing the total number of new notifiable cancer patients treated with radiotherapy in 2012 by the total number of cancer patients diagnosed in the same year in each country. An analysis of the characteristics of patients and treatments in a series of 300 consecutive radiotherapy patients shed light on the particular patient and treatments profile in the participating countries.

RESULTS

The median oRTU rate for the group of nine countries was 52% (47-56%). The median aRTU rate for the nine countries was 28% (9-46%). These results show that the real proportion of cancer patients receiving RT is lower than the optimal RTU with a rate difference between 10-42.7%. The median percent-unmet need was 47% (18-82.3%).

CONCLUSIONS

The optimal RTU rate in middle-income countries did not differ significantly from that previously found in high-income countries. The actual RTU rates were consistently lower than the optimal, in particular in countries with limited resources and a large population.

Impact of Interstitial Lung Disease Classification on the Development of Acute Exacerbation of Interstitial Lung Disease and Prognosis in Patients with Stage III Non-Small-Cell Lung Cancer and Interstitial Lung Disease Treated With Chemoradiotherapy

Introduction: Data on the efficacy and risk of curative-intent chemoradiotherapy in patients with inoperable stage III non-small-cell lung cancer (NSCLC) and interstitial lung disease (ILD) are limited. The aim of this study was to explore the impact of ILD classification on acute exacerbation (AE) of ILD and prognosis in patients with stage III NSCLC and ILD treated with chemoradiotherapy.

Materials and methods: We retrospectively reviewed the medical records of patients with stage III NSCLC and ILD treated with curative-intent chemoradiotherapy as the first-line treatment at the Shizuoka Cancer Center between June 2009 and May 2014.

Results: Of 37 patients, 17 (46%) developed AE of ILD worse than grade 3 within 1 year after the last irradiation. In univariate analysis, the incidence rate of AE of ILD was lower in patients with a non-usual interstitial pneumonia (UIP) pattern than in those with a UIP pattern. Multivariate analysis showed that ILD classification was significantly associated with the incidence of AE of ILD. The median overall survival (OS) durations in patients with a non-UIP pattern and a UIP pattern were 16.5 and 9.3 months, respectively. In univariate analysis, patients with a non-UIP pattern showed better survival. Multivariate analysis showed that ILD classification was a significant independent prognostic factor.

Conclusion: The incidence of AE of ILD was high in patients with stage III NSCLC and ILD treated with chemoradiotherapy as the first-line treatment. However, diagnosis of a non-UIP pattern could predict lower risk of AE of ILD and longer OS durations.

Proton therapy for thoracic reirradiation of non-small cell lung cancer

Lung cancer is a leading cause of cancer death with frequent local failures after initial curative-intent treatment. Locally recurrent non-small cell lung cancer represents a challenging clinical scenario as patients have often received prior radiation as part of a definitive treatment regimen. Proton beam therapy, through its characteristic Bragg peak and lack of exit dose is a potential means of minimizing the toxicity to previously irradiated organs and improving the therapeutic ratio. This article aims to review the rationale for the use of proton beam therapy for treatment of locally recurrent non-small cell lung cancer, highlight the current published experience on the feasibility, efficacy, and limitations of proton beam reirradiation, and discuss future avenues for improved patient selection and treatment delivery.

Mathematical Modelling for Patient Selection in Proton Therapy

Proton beam therapy (PBT) is still relatively new in cancer treatment and the clinical evidence base is relatively sparse. Mathematical modelling offers assistance when selecting patients for PBT and predicting the demand for service. Discrete event simulation, normal tissue complication probability, quality-adjusted life-years and Markov Chain models are all mathematical and statistical modelling techniques currently used but none is dominant. As new evidence and outcome data become available from PBT, comprehensive models will emerge that are less dependent on the specific technologies of radiotherapy planning and delivery.

Radiotherapy in Italy for Non-Small Cell Lung Cancer: Patterns of Care Survey

Aims and Background

Surveys in clinical practice are useful to find how current clinical approaches follow recommendations from evidence-based medicine, to stimulate discussion in a multidisciplinary team, and to hypothesize collaborative multi-centric trials. To assess management strategies for the use of radiotherapy in the treatment of lung cancer in Italy, in 2009, the Italian Society of Radiation Oncology Lung Cancer Study Group proposed the survey to all Italian radiation oncology institutions. Results were compared with literature data and international reports.

Study Design

Questionnaires on patterns of care of non-small cell lung cancer were sent to radiation oncology centers active at June 2009 and evaluated data recorded in 2008.

Results

A total of 65 of 143 Italian centers responded to the questionnaire. The responding centers reflect the distribution of radiotherapy centers throughout the country. Of the treated patients, 55.2% were stage III, and most cases had a good performance status. FDG-PET was routinely used by 51% of centers for diagnostic and contouring phases. Postoperative radiotherapy was prescribed to pN1 and pN2 patients in 42.2% and 98.5%, respectively. The possible use of neo-adjuvant concomitant chemoradiation was declared by 70% of responders. A sequential chemoradiation approach was actually used in 43.6% of cases, induction chemotherapy followed by concomitant radiochemotherapy in 42.4%, and upfront concomitant radiochemotherapy in only 14%. In 53% of the institutions, patients have a clinical examination by a radiation oncologist only after the beginning of chemotherapy and in 82.4% of cases they have already received 2–4 cycles of chemotherapy. Most of the institutions exclude elective nodal irradiation from routine application. Total dose and fractionation in adjuvant, neoadjuvant, curative and palliative settings confirm literature data. There were significant differences in treatment planning constraints applied for lung, esophageal and cardiac tissues. Of the responding centers, 41% had stereotactic therapy for primary inoperable lung cancer and for metastatic lesions.

Conclusions

In Italy, daily practice differs in some ways from the evidence supported by the results of meta-analyses/clinical trials as regards concurrent chemoradiation approaches. It could be postulated that there is an urgent need for groups that collaborate with the other societies involved in the treatment of non-small cell lung cancer in order to offer the best therapy to our patients.

EGFR tyrosine kinase inhibitor HS-10182 increases radiation sensitivity in non-small cell lung cancers with EGFR T790M mutation

Objective:

To investigate the potential of HS-10182, a second-generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), as a radiosensitizer in non-small cell lung cancer (NSCLC).

Methods:

Two cell lines of NSCLCs, A549 that possesses wild-type (WT) EGFRs and H1975 that possesses EGFR L858R/T790M double mutations, were treated with HS-10182 at various concentrations, and cell viabilities were determined using the MTS assay. The cells were tested by clonogenic survival assays to identify the radiosensitivity of both groups. Western blot was performed to analyze the expression of phosphorylated EGFR, AKT, DNA-dependent protein kinase, and catalytic subunit (DNA-PKcs) proteins. Immunofluorescence analyses were performed to examine the formation and changes in nuclear γ-H2AX foci. Cell apoptosis was examined by flow cytometry and Western blots for cleaved caspase-3, -8, -9, and cleaved poly ADP-ribose polymerase (PARP). Furthermore, we established xenograft models in mice and the effects of different treatments on tumor growth were then assessed.

Results:

Clonogenic survival assays revealed that HS-10182 significantly enhanced the radiosensitivity of H1975 cells but not A549 cells [dose enhancement ratios (DERs)=2.36 (P < 0.05) vs. 1.43 (P > 0.05)]. Western blot results showed that HS-10182 increased the levels of cleaved caspase-3, -8, -9, and cleaved PARP in H1975 cells but not in A549 cells. In addition, flow cytometry analysis showed that HS-10182 enhanced irradiation-induced apoptosis in H1975. Immunofluorescence results found that HS-10182 increased the average number of γ-H2AX foci after irradiation in H1975 cells, but not in A549 cells. Combined radiation and HS-10182 treatment increased the expression of DNA-PKcs but this increase was more significant in H1975 cells than in A549 cells. Moreover, HS-10182 suppressed the increased expression of Rad50 in H1975 cells in response to irradiation. In vivo experiments found that the combined therapy significantly inhibited tumor growth.

Conclusions:

HS-10182 enhances the radiosensitivity of H1975 cells which is possibly because that HS-10182 could enhance irradiation-induced apoptosis, increase irradiation-induced DNA damage, and cause a delay in DNA damage repair. Our findings suggest that radiotherapy combined HS-10182 is a novel treatment for lung cancer cells which have acquired the T790M mutation. HS-10182 could be brought to the clinic as a radiosensitizer in NSCLCs with the EGFR T790M mutation.

Implantation of computed tomography-guided Iodine-125 seeds in combination with chemotherapy for the treatment of stage III non-small cell lung cancer

Purpose

We investigated the role of computed tomography (CT)-guided Iodine-125 (¹²⁵I) seed implantation in combination with chemotherapy for the treatment of stage III non-small cell lung carcinoma (NSCLC).

Material and methods

The data from 182 patients with stage III NSCLC who were treated with radioactive ¹²⁵I seed implantation between June 2002 and June 2009, and who received sequential platinum-based combination chemotherapy using the most common combination of platinum and gemcitabine, were retrospectively reviewed. The 182 patients received a prescribed dose of 110.0 Gy, with a median radioactivity of 0.70 mCi (range, 0.64-0.78 mCi, 2.37-3.26 × 107 Bq). The median number of ¹²⁵I seeds was 38 pellets (range, 6-105 pellets). The median post-operation dose covering 100% of the target volume (D₁₀₀) was 94.5 Gy (range, 54.6-125.5 Gy). The median D₉₀ was 143.0 Gy (range, 121.6-184.0).

Results

The 1-, 3-, and 5-year overall survival rates were 83.35%, 25.57%, and 11.34%, respectively; the median survival time was 24.76 months. At 1, 3, and 5 years, the local control rates were 92.01%, 86.51%, and 76.45%, respectively; the median local control time was 25.28 months. For patients with stage IIIA and IIIB NSCLC, the median survival times were 26.67 and 24.59 months, respectively (p = 0.2). Pre-treatment hemoglobin level, tumor volume, and postoperative D₁₀₀ were significantly associated with survival. A total of 24 patients experienced pneumothorax (incidence rate, 13.20%), and 17 patients experienced hemothorax (incidence rate, 5.0%).

Conclusions

CT-guided ¹²⁵I seed implantation combined with chemotherapy is an effective, minimally invasive method for the treatment of stage III NSCLC. Furthermore, hemoglobin levels before treatment, D₁₀₀, and the maximum diameter of the tumor may be prognostic factors in patients with NSCLC treated sequentially with radiotherapy and chemotherapy.