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

Correlation of Ktrans derived from dynamic contrast-enhanced MRI with treatment response and survival in locally advanced NSCLC patients undergoing induction immunochemotherapy and concurrent chemoradiotherapy

PURPOSE

This study aimed to investigate the prognostic significance of pretreatment dynamic contrast-enhanced (DCE)-MRI parameters concerning tumor response following induction immunochemotherapy and survival outcomes in patients with locally advanced non-small cell lung cancer (NSCLC) who underwent immunotherapy-based multimodal treatments.

MATERIAL AND METHODS

Unresectable stage III NSCLC patients treated by induction immunochemotherapy, concurrent chemoradiotherapy (CCRT) with or without consolidative immunotherapy from two prospective clinical trials were screened. Using the two-compartment Extend Tofts model, the parameters including Ktrans, Kep, Ve, and Vp were calculated from DCE-MRI data. The apparent diffusion coefficient was calculated from diffusion-weighted-MRI data. The receiver operating characteristic (ROC) curve and the area under the curve (AUC) were used to assess the predictive performance of MRI parameters. The Cox regression model was used for univariate and multivariate analysis.

RESULTS

111 unresectable stage III NSCLC patients were enrolled. Patients received two cycles of induction immunochemotherapy and CCRT, with or without consolidative immunotherapy. With the median follow-up of 22.3 months, the median progression-free survival (PFS) and overall survival (OS) were 16.3 and 23.8 months. The multivariate analysis suggested that Eastern Cooperative Oncology Group score, TNM stage and the response to induction immunochemotherapy were significantly related to both PFS and OS. After induction immunochemotherapy, 67 patients (59.8%) achieved complete response or partial response and 44 patients (40.2%) had stable disease or progressive disease. The Ktrans of primary lung tumor before induction immunochemotherapy yielded the best performance in predicting the treatment response, with an AUC of 0.800. Patients were categorized into two groups: high-Ktrans group (n=67, Ktrans＞164.3×10-3/min) and low-Ktrans group (n=44, Ktrans≤164.3×10-3/min) based on the ROC analysis. The high-Ktrans group had a significantly higher objective response rate than the low-Ktrans group (85.1% (57/67) vs 22.7% (10/44), p<0.001). The high-Ktrans group also presented better PFS (median: 21.1 vs 11.3 months, p=0.002) and OS (median: 34.3 vs 15.6 months, p=0.035) than the low-Ktrans group.

CONCLUSIONS

Pretreatment Ktrans value emerged as a significant predictor of the early response to induction immunochemotherapy and survival outcomes in unresectable stage III NSCLC patients who underwent immunotherapy-based multimodal treatments. Elevated Ktrans values correlated positively with enhanced treatment response, leading to extended PFS and OS durations.

Optimizing lung cancer radiation therapy: A systematic review of multifactorial risk assessment for radiation-induced lung toxicity

BACKGROUND

Radiation therapy (RT) is essential in treating advanced lung cancer, but may lead to radiation pneumonitis (RP). This systematic review investigates the use of pulmonary function tests (PFT) and other parameters to predict and mitigate RP, thereby improving RT planning.

METHODS

A systematic review sifted through PubMed and on BioMed Central, targeting articles from September 2005 to December 2022 containing the keywords: Lung Cancer, Radiotherapy, and pulmonary function test.

RESULTS

From 1153 articles, 80 were included. RP was assessed using CTCAEv.4 in 30 % of these. Six studies evaluated post-RT quality of life in lung cancer patients, reporting no decline. Patients with RP and chronic obstructive pulmonary disease (COPD) generally exhibited poorer overall survival. Notably, forced expiratory volume in one second (FEV1) and diffusing capacity of the lung for carbon monoxide (DLCO) declined 24 months post-RT, while forced vital capacity (FVC) stayed stable. In the majority of studies, age over 60, tumors located in the lower part of the lung, and low FEV1 before RT were associated with a higher risk of RP. Dosimetric factors (V5, V20, MLD) and metabolic imaging emerged as significant predictors of RP risk. A clinical checklist blending patient and tumor characteristics, PFT results, and dosimetric criteria was proposed for assessing RP risk before RT.

CONCLUSION

The review reveals the multifactorial nature of RP development following RT in lung cancer. This approach should guide individualized management and calls for a prospective study to validate these findings and enhance RP prevention strategies.

Hypofractionated Radiotherapy followed by Hypofractionated Boost with weekly concurrent chemotherapy for Unresectable Stage III Non-Small Cell Lung Cancer: Results of A Prospective Phase II Study (GASTO-1049)

PURPOSE

We launched a prospective phase 2 clinical trial to explore the safety and efficacy of hypofractionated radiation therapy (hypo-RT) followed by hypofractionated boost (hypo-boost) combined with concurrent weekly chemotherapy in patients with unresectable locally advanced non-small cell lung cancer (LA-NSCLC).

METHODS AND MATERIALS

Patients with newly diagnosed LA-NSCLC with unresectable stage III disease were recruited between June 2018 and June 2020. Patients were treated with hypo-RT (40 Gy in 10 fractions) followed by hypo-boost (24-28 Gy in 6-7 fractions) combined with concurrent weekly chemotherapy (docetaxel 25 mg/m2 and nedaplatin 25 mg/m2). The primary endpoint of the study was progression-free survival (PFS), and the secondary endpoints included overall survival (OS), locoregional failure-free survival (LRFS), distant metastasis-free survival (DMFS), objective response rate (ORR), and toxicities.

RESULTS

From June 2018 to June 2020, 75 patients were enrolled with a median follow-up duration of 28.0 months. The ORR of the whole cohort was 94.7%. Disease progression or death was recorded in 44 (58.7%) patients, with a median PFS of 21.6 months (95% confidence interval [CI], 15.6-27.6 months). The 1- and 2-year PFS rates were 81.3% (95% CI, 72.5%-90.1%) and 43.3% (95% CI, 31.5%-55.1%), respectively. The median OS, DMFS, and LRFS had not been reached at the time of the last follow-up. The 1- and 2-year OS rates were 94.7% (95% CI, 89.6%-99.8%) and 72.4% (95% CI, 62.0%-82.8%), respectively. The most frequent acute nonhematologic toxicity was radiation esophagitis. Grade (G) 2 and G3 acute radiation esophagitis were observed in 20 (26.7%) and 4 (5.3%) patients, respectively. Thirteen patients (13/75, 17.3%) had G2 pneumonitis and no G3-G5 acute pneumonitis occurred during follow-up.

CONCLUSIONS

Hypo-RT followed by hypo-boost combined with concurrent weekly chemotherapy could yield satisfactory local control and survival outcomes with moderate radiation-induced toxicity in patients with LA-NSCLC. The new potent hypo-CCRT regimen significantly shortened treatment time and provided the potential opportunity for the combination of consolidative immunotherapy.

Efficacy and safety of particle therapy for inoperable stage II-III non-small cell lung cancer: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

Particle therapy, mainly including carbon-ion radiotherapy (CIRT) and proton beam therapy (PBT), has dose distribution advantages compared to photon radiotherapy. It has been widely reported as a promising treatment method for early non-small cell lung cancer (NSCLC). However, its application in locally advanced non-small cell lung cancer (LA-NSCLC) is relatively rare, and its efficacy and safety are inconclusive. This study aimed to provide systematic evidence for evaluating the efficacy and safety of particle therapy for inoperable LA-NSCLC.

METHODS

To retrieve published literature, a systematic search was conducted in PubMed, Web of Science, Embase, and Cochrane Library until September 4, 2022. The primary endpoints were local control (LC) rate, overall survival (OS) rate, and progression-free survival (PFS) rate at 2 and 5 years. The secondary endpoint was treatment-related toxicity. The pooled clinical outcomes and 95% confidence intervals (CIs) were calculated by using STATA 15.1.

RESULTS

Nineteen eligible studies with a total sample size of 851 patients were included. The pooled data demonstrated that the OS, PFS, and LC rates at 2 years of LA-NSCLC treated by particle therapy were 61.3% (95% CI = 54.7-68.7%), 37.9% (95% CI = 33.8-42.6%) and 82.2% (95% CI = 78.7-85.9%), respectively. The pooled 5-year OS, PFS, and LC rates were 41.3% (95% CI = 27.1-63.1%), 25.3% (95% CI = 16.3-39.4%), and 61.5% (95% CI = 50.7-74.6%), respectively. Subgroup analysis stratified by treatment type showed that the concurrent chemoradiotherapy (CCRT, PBT combined with concurrent chemotherapy) group had better survival benefits than the PBT and CIRT groups. The incidence rates of grade 3/4 esophagitis, dermatitis, and pneumonia in LA-NSCLC patients after particle therapy were 2.6% (95% CI = 0.4-6.0%), 2.6% (95% CI = 0.5-5.7%) and 3.4% (95% CI = 1.4-6.0%), respectively.

CONCLUSIONS

Particle therapy demonstrated promising efficacy and acceptable toxicity in LA-NSCLC patients.

Gut Microbiome Is Associated With the Response to Chemoradiotherapy in Patients With Non-small Cell Lung Cancer

PURPOSE

To explore the dynamic change of gut microbiota and its predictive role in progression-free survival (PFS) in non-small cell lung cancer (NSCLC) after concurrent chemoradiotherapy (CCRT).

METHODS AND MATERIALS

Forty-one patients with NSCLC in 2 phase 2 trials (NCT02573506 and NCT03006575) were analyzed. A total of 102 fecal samples were collected at 3 time points (T0, before CCRT; T1, 2 weeks after the initiation of CCRT; and T2, the end of CCRT). Gut microbiota composition and functionality were analyzed by 16S rRNA gene sequencing and shotgun metagenomics, respectively. Alpha diversity, taxonomic composition, and KEGG functional pathways were compared between patients in the long-PFS group (PFS ≥11.0 months) and short-PFS group (PFS <11.0 months). A random forest classifier was constructed to identify microbial signature related to PFS. Clinical and microbial factors potentially predictive of PFS were assessed in the univariate and multivariate Cox regression analysis.

RESULTS

The abundance of Bacteroidota and Proteobacteria increased, while the abundance of Firmicutes decreased after CCRT. Shannon index (P = .006) and PD index (P = .022) were significantly higher in the long-PFS group than for those in the short-PFS group at T1. The PFS-prediction microbial signature at T1 included unclassified members of the Lanchospiraceae spp., such as NK4A136 and UCG-003 groups, Dorea sp., various strains from within the Eubacterium hallii and E. siraeum groups, and an unclassified member of the Muribaculaceae, which yielded an area under the ROC curve of 0.87. These discriminatory genera mostly belong to phylum Firmicutes/family Clostridia. Multivariate analysis indicated PD index (HR = 8.036, P = .016) and the abundance of Dorea sp. at T1 (HR = 4.186, P = .043) were independent predictors of PFS. The KEGG pathways at T1 overrepresented in the long-PFS group included fatty acid metabolism, fatty acid biosynthesis, and arginine biosynthesis. Those overrepresented in the short-PFS group included lipopolysaccharide biosynthesis, ascorbate and aldarate metabolism, and biosynthesis of vancomycin group antibiotics.

CONCLUSIONS

Gut microbiota composition and functionality at 2 weeks after the initiation of CCRT were associated with PFS in NSCLC. Further research is needed to confirm these results.

Hypofractionated concurrent chemoradiotherapy related lymphopenia and its association with survival in locally advanced non-small cell lung cancer patients

Background

To evaluate longitudinal changes of concurrent chemoradiotherapy (CCRT) related lymphopenia and its association with survival in locally advanced non-small cell lung cancer (LA-NSCLC) patients.

Methods

Total lymphocyte count (TLC) at baseline, weekly intervals during CCRT and monthly intervals up to 12 months after CCRT were documented. The Common Terminology Criteria for Adverse Events version 5.0 was used to grade the severity of lymphopenia. Cox regression analysis was performed to evaluate the association between overall survival (OS) and CCRT related lymphopenia at different timepoints. Logistic regression model was used to determine the clinical factors associated with TLC level.

Results

381 LA-NSCLC patients treated with definitive CCRT without consolidation therapy (NCT02573506/NCT02577341) between 2011 to 2020 were analyzed. With a median follow-up of 45.8 months, the median OS was 41.0 months for all patients. Univariable analysis demonstrated that the 3 weeks during CCRT Grade (G) 4 lymphopenia (P=0.018), 2 months after CCRT G1-4 lymphopenia (P=0.004), 6 months after CCRT (6m-post-CCRT) G1-4 lymphopenia (P=0.001), and TLC nadir (P=0.020) were significantly associated with poorer OS. Multivariable analysis suggested that 6m-post-CCRT G1-4 lymphopenia (HR 2.614; P=0.041) were one of the independent predictors of OS. Further analysis inferred that radiation dose (OR: 1.328; P=0.005), GTV volume (OR: 1.004; P=0.036), and baseline TLC (OR: 0.288; P=0.001) were associated with 6m-post-CCRT lymphopenia.

Conclusion

The persistent lymphopenia at 6 months after CCRT was an independent prognostic factor of OS in LA-NSCLC patients. Higher radiation dose, larger gross tumor volume and lower baseline TLC were significantly related to 6m-post-CCRT lymphopenia.

CT radiomics-based long-term survival prediction for locally advanced non-small cell lung cancer patients treated with concurrent chemoradiotherapy using features from tumor and tumor organismal environment

Background

Definitive concurrent chemoradiotherapy (CCRT) is the standard treatment for locally advanced non-small cell lung cancer (LANSCLC) patients, but the treatment response and survival outcomes varied among these patients. We aimed to identify pretreatment computed tomography-based radiomics features extracted from tumor and tumor organismal environment (TOE) for long-term survival prediction in these patients treated with CCRT.

Methods

A total of 298 eligible patients were randomly assigned into the training cohort and validation cohort with a ratio 2:1. An integrated feature selection and model training approach using support vector machine combined with genetic algorithm was performed to predict 3-year overall survival (OS). Patients were stratified into the high-risk and low-risk group based on the predicted survival status. Pulmonary function test and blood gas analysis indicators were associated with radiomic features. Dynamic changes of peripheral blood lymphocytes counts before and after CCRT had been documented.

Results

Nine features including 5 tumor-related features and 4 pulmonary features were selected in the predictive model. The areas under the receiver operating characteristic curve for the training and validation cohort were 0.965 and 0.869, and were reduced by 0.179 and 0.223 when all pulmonary features were excluded. Based on radiomics-derived stratification, the low-risk group yielded better 3-year OS (68.4% vs. 3.3%, p < 0.001) than the high-risk group. Patients in the low-risk group had better baseline FEV1/FVC% (96.3% vs. 85.9%, p = 0.046), less Grade ≥ 3 lymphopenia during CCRT (63.2% vs. 83.3%, p = 0.031), better recovery of lymphopenia from CCRT (71.4% vs. 27.8%, p < 0.001), lower incidence of Grade ≥ 2 radiation-induced pneumonitis (31.6% vs. 53.3%, p = 0.040), superior tumor remission (84.2% vs. 66.7%, p = 0.003).

Conclusion

Pretreatment radiomics features from tumor and TOE could boost the long-term survival forecast accuracy in LANSCLC patients, and the predictive results could be utilized as an effective indicator for survival risk stratification. Low-risk patients might benefit more from radical CCRT and further adjuvant immunotherapy.

Trial registration:

retrospectively registered.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13014-022-02136-w.

Evaluation of the efficacy and feasibility of concurrent weekly docetaxel-nedaplatin and hypo-fractionated radiotherapy in atypical histologic subtypes of primary and metastatic mediastinal malignancies

Background

We aimed to evaluate the efficacy and feasibility of concurrent weekly docetaxel-nedaplatin and hypo-fractionated radiotherapy (hypo-RT) in atypical histologic subtypes of primary and metastatic mediastinal malignancies.

Methods

Fifty-four patients diagnosed with atypical primary or metastatic mediastinal malignancies were retrospectively reviewed. 30 patients received concurrent weekly docetaxel and nedaplatin and hypo-RT (CChRT group) and 24 patients had hypo-RT alone (hRT group). Overall response rate (ORR), in-field locoregional progression-free survival (LPFS) and toxicities were analyzed. The radiobiological effect was evaluated by the LQRGC/TCP model, incorporating four “R”s of radiobiology, Gompertzian tumor growth and radio-sensitizing effect of chemotherapeutic agent. The biologically effective doses (BEDs) were calculated.

Results

The median follow-up time was 29.2 months for all patients. The ORR was 86.7% in CChRT group, compared with 62.5% in hRT group (p=0.033). The 2-year in-field LPFS of CChRT and hRT group was 73.4% and 47.3%, respectively (p=0.003). There was no significant difference of any >=Grade 3 toxicities between the two groups (p=0.754). The mean total dose and mean BED by the LQRGC/TCP model in CChRT group were 58.2Gy and 72.34Gy, versus 52.6Gy and 67.25Gy in hRT group.

Conclusions

Concurrent weekly docetaxel-nedaplatin and hypo-RT achieved promising in-field LPFS and tolerable toxicities compared with hypo-RT alone in different histologic subtypes of primary and metastatic mediastinal malignancies.

Hypofractionated Radiation Therapy Combined With Weekly Chemotherapy in Patients With Unresectable or Recurrent Thymic Epithelial Tumor: A Prospective, Single-Arm Phase 2 Study (GASTO-1042)

PURPOSE

This prospective phase 2 study aimed to evaluate the efficacy and safety of hypofractionated radiation therapy (HRT) combined with concurrent weekly chemotherapy in patients with unresectable or recurrent thymic epithelial tumors (TETs).

METHODS AND MATERIALS

Patients with unresectable or recurrent intrathoracic TETs that could be encompassed within the radiation fields were enrolled. HRT using intensity modulated radiation therapy (IMRT) technique was administered with 3 different levels of radiation doses (51 Gy/17 fractions (fx), 48 Gy/12 fx, and 45 Gy/9 fx; biologically effective dose of 66.3-67.5Gy), combined with weekly docetaxel (25 mg/m²) and nedaplatin (25 mg/m²). Weekly thymosin α1 (1.6 mg) was administered from the start to 2 months after radiation therapy. The objective response rate (ORR), progression-free survival (PFS), overall survival (OS), health-related quality of life (QOL), and toxicity were recorded.

RESULTS

Fifty eligible patients enrolled from August 1, 2018, to July 1, 2020, were analyzed. Most patients (82.0%) had stage IVB tumors. Patients had IMRT-HRT (36-51 Gy in 9-17 fx, median biologically effective dose of 67.2 Gy) and concurrent weekly docetaxel/nedaplatin (2-4 cycles). During a median follow-up of 25.0 months (14.0-40.0), the ORR was 83.7%, the 2-year PFS was 59.1%, and the 2-year OS was 90.0%. There was 1 (2.0%) in-field recurrence while 19 (38.0%) patients developed out-of-field recurrence. Grade 3 pneumonitis was observed in 1 patient (2.0%). The ORR, 2-year PFS, 2-year OS, and toxicity were similar among 3 dose levels. Fourteen (28.0%) patients had 2 to 4 courses of radiation therapy because of recurrent diseases. Only 1 suffered from grade 1 pulmonary fibrosis during follow-up. Most patients (88%) maintained a stable QOL within 1 year after radiation therapy.

CONCLUSIONS

IMRT-HRT and concurrent weekly docetaxel/nedaplatin was effective and well tolerated in unresectable or recurrent TETs. Considering the common out-of-field recurrence, this combined regimen could be an option for repeated radiation therapy. Thymosin α1 might help lower the incidence of pneumonitis and maintain the QOL.

Four-Phase, Definitive Chemoradiation for a Real-World (Poor Risk and/or Elderly) Patient Population With Locally Advanced Non-small Cell Lung Cancer

Introduction With the incorporation of modernized radiotherapy, chemotherapy, and immunotherapy, treatment outcomes have improved for patients with locally advanced, unresectable diseases. Elderly or poor performance status patients comprise more than half of non-small cell lung cancer (NSCLC) patients, but they are often underrepresented or excluded in clinical trials. Split-course concurrent chemoradiotherapy can be an effective treatment, showing good adherence and a favorable toxicity profile for unresectable, locally advanced NSCLC. Method We identified locally advanced NSCLC cancer patients via a single institution retrospective study. Patients were treated using a four-phase, split-course external beam radiotherapy approach with concurrent chemotherapy. The primary endpoints analyzed were completion rate, incidence, and severity of treatment-related toxicities, progression-free survival (PFS), and median overall survival (OS). Results Thirty-nine locally advanced lung cancer patients were treated with split-course chemoradiation (CRT). The median age at diagnosis was 73 years old. Seventeen patients had an Eastern Cooperative Oncology Group (ECOG) performance score of 2. Twenty-three patients had a clinical diagnosis of chronic obstructive pulmonary disease (COPD), and 10 patients were on home oxygen at the time of diagnosis. All patients completed 6000 centigrays (cGy) of radiation, and 95% of the patients completed at least three cycles of concurrent chemotherapy. No patients experienced grade 3 to 5 acute thoracic toxicities. Overall median survival was 12.7 months, and PFS was 7.5 months. Conclusion Our retrospective analysis of 39 poor risk and/or elderly patients with locoregional NSCLC treated with concurrent CRT via a split-course regimen suggests favorable oncologic outcomes and superb treatment completion rates and toleration.

Sequential Hypofractionated versus Concurrent Twice-Daily Radiotherapy for Limited-Stage Small-Cell Lung Cancer: A Propensity Score-Matched Analysis

Background: As there are no randomized trials comparing twice-daily with sequential hypofractionated (sequential hypo) radiotherapy regimens for limited-stage small-cell lung cancer (LS-SCLC). This study aimed to compare these two regimens for LS-SCLC by propensity score-matched analysis (PSM). Methods: We retrospectively analyzed 108 LS-SCLC patients between January 2015 and July 2019. All patients received concurrent twice-daily or sequential hypo radiotherapy. The survival, failure patterns, and toxicities were evaluated before and after PSM. Results: Before PSM, multivariate analysis showed that patients treated with sequential hypo had a significantly better overall survival (OS) and distant metastasis-free survival (DMFS) (HR = 0.353, p = 0.009; HR = 0.483, p = 0.039, respectively). Total radiotherapy time ≥ 24 days and stage III (HR = 2.454, p = 0.004; HR = 2.310, p = 0.004, respectively) were poor prognostic indicators for OS. Patients with a total radiotherapy time ≥ 24 days and N2−3 were more likely to recur than others (HR = 1.774, p = 0.048; HR = 2.369, p = 0.047, respectively). N2−3 (HR = 3.032, p = 0.011) was a poor prognostic indicator for DMFS. After PSM, being aged ≥65 years was associated with poorer OS, relapse-free survival (RFS) and DMFS (p < 0.05). A total radiotherapy time of ≥24 days was a poor prognostic indicator for OS and RFS (HR = 2.671, p = 0.046; HR = 2.370, p = 0.054, respectively). Although there was no significant difference, the patients in the sequential hypo group had a trend towards a better OS. The failure pattern between the two groups showed no difference. More patients had grade 1−2 esophagitis in the twice-daily group (p = 0.001). Conclusions: After propensity matching, no difference was shown in survival and failure. The sequential hypo schedule was associated with comparable survival and less toxicity and may be used as an alternative to concurrent twice-daily regimens.

Efficacy of thymosin α1 in management of radiation pneumonitis in patients with locally advanced non-small cell lung cancer treated with concurrent chemoradiotherapy: A Phase 2 Clinical Trial (GASTO-1043)

PURPOSE

To evaluate the efficacy of thymosin α1 in management of radiation pneumonitis (RP) in patients with locally advanced non-small cell lung cancer (LANSCLC) treated with concurrent chemoradiotherapy (CCRT).

METHODS AND MATERIALS

This phase II, single-arm trial enrolled patients with unresectable LANSCLC of 18 to 75 years' old and an Eastern Cooperative Oncology Group performance status of 0 to 1. Eligible patients received definitive CCRT and weekly thymosin α1 from the start of CCRT till 2 months after CCRT. Patients were administered 51 Gy in 17 daily fractions or 40 Gy in 10 daily fractions in the first course followed by a re-evaluation and those patients without disease progression had an adaptive plan of 15 Gy in 5 daily fractions or 24 Gy in 6 daily fractions as a boost. Concurrent chemotherapy consisted of weekly docetaxel (25 mg/m²) and nedaplatin (25 mg/m²) during radiation therapy. The primary endpoint was the incidence of Grade (G) ≥2 RP. Secondary endpoints included the incidence of late pulmonary fibrosis, total lymphocyte count (TLC), serum C-reactive protein (CRP) levels, and the composition of gut microbiota. TLC and CRP data were collected at baseline, 2-3 weeks during CCRT, the end of CCRT, 2 and 6 months after CCRT. Fecal samples were collected at baseline and the end of CCRT. Patients treated with CCRT but without thymosin α1 intervention during the same period were selected as the control group by the propensity score matching method.

RESULTS

Sixty-nine patients were enrolled in the study, and another 69 patients were selected as the control group. The incidence of G≥2 RP was lower in the study group compared with control cases (36.2% vs 53.6%, P=0.040). G1 late pulmonary fibrosis occurred in 2 (3.7%) patients of the control group compared with no event in the study group (P=0.243). Compared with the control group, the incidence of G3-4 lymphopenia (19.1% vs. 62.1%, P<0.001) was lower, and the median TLC nadir (0.51 k/µL vs. 0.30 k/µL, P<0.001) was higher in the study group. The proportion of patients with maximum CRP≥100 mg/L was lower in the study group (13.8% vs. 29.7% P=0.029). The diversity and community composition of the gut microbiota were not significantly different between the two groups.

CONCLUSIONS

Administration of thymosin α1 during and after CCRT was associated with significant reductions in G≥2 RP and G3-4 lymphopenia in patients with LANSCLC compared to historic controls.

Analysis of Gut Microbiota Signature and Microbe-Disease Progression Associations in Locally Advanced Non-Small Cell Lung Cancer Patients Treated With Concurrent Chemoradiotherapy

Purpose

To evaluate the association of gut microbiome signature and disease progression in locally advanced non-small cell lung cancer (LA-NSCLC) patients treated with concurrent chemoradiotherapy (CCRT) by fecal metagenome analysis.

Methods

Metagenome-wide association studies on baseline fecal samples from 18 LA-NSCLC patients before CCRT and 13 controls from healthy first-degree relatives were performed. Among the 18 LA-NSCLC patients, six patients were defined as the long progression-free survival (long-PFS) group (PFS≥11 months) while another 12 were in the short-PFS group (PFS<11 months). Alpha diversity, taxonomic composition, and Kyoto Encyclopedia of Genes and Genomes (KEGG) functional pathways were compared between groups.

Results

The Firmicutes/Bacteroidetes value of long-PFS group was higher than those of short-PFS (p=0.073) and healthy individual groups (p=0.009). Meanwhile, long-PFS group had significantly higher diversities in Fungi, Archaea, and Viruses than short-PFS group. The KEGG pathways overrepresented in short-PFS group included fructose and mannose metabolism (p=0.028), streptomycin biosynthesis (p=0.028), acarbose and validamycin biosynthesis (p=0.013), ribosome biogenesis in eukaryotes (p=0.035), biosynthesis of vancomycin group antibiotics (p=0.004), apoptosis-fly (p=0.044), and tetracycline biosynthesis (p=0.044), while those overrepresented in long-PFS group included fatty acid biosynthesis (p=0.035), fatty acid metabolism (p=0.008), vancomycin resistance (p=0.008), longevity regulating pathway-worm (p=0.028), type II diabetes mellitus (p=0.004), and viral carcinogenesis (p=0.003). Further analysis of antibiotic resistome demonstrated that the short-PFS group had a trend with more antibiotic resistance genes than healthy control (p=0.070) and long-PFS groups (p=0.218). The vancomycin resistance sequences were significantly enriched in the long-PFS group compared to the short-PFS group (p=0.006).

Conclusions

The baseline gut microbiome composition and functionality might be associated with PFS in LA-NSCLC treated with CCRT. The outcome of CCRT might be modulated through bacterial metabolic pathways. The antibiotic resistance genes might play a role in disease progression and provide potential information on the relationship between the use of antibiotics and treatment efficacy of CCRT in LA-NSCLC.

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

INTRODUCTION

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

METHODS & MATERIALS

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

RESULTS

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

CONCLUSION

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