Safety and efficacy of thoracic radiotherapy combined with chemo-immunotherapy in patients with extensive-stage small cell lung cancer: a multicenter retrospective analysis.

Background: Immunotherapy has greatly increased the survival time of patients with extensive-stage small cell lung cancer (ES-SCLC), and is now a standard first-line treatment for these patients. Increasing evidence suggests a possible synergistic effect between immunotherapy and radiotherapy, yet there is a paucity of evidence regarding the efficacy and safety of thoracic radiotherapy (TRT) combined with chemo-immunotherapy for ES-SCLC. Methods: The medical records of 78 consecutive patients with ES-SCLC who received TRT in combination with chemo-immunotherapy at Jinling Hospital and Jiangsu Cancer Hospital from January 2019 to January 2023 were retrospectively reviewed. The median overall survival (mOS) time and median progression-free survival (mPFS) time were used to evaluate efficacy, and the incidence of adverse events (AEs) was used to evaluate safety. Results: The median follow-up time was 31.9 months, the objective response rate (ORR) was 59%, and the disease control rate (DCR) was 89.8%. The mOS time was 20.0 months, and the 6-month OS rate was 95%. The mPFS time was 9.2 months, and the 6-month PFS rate was 78%. There were no treatment-related deaths. The incidence of pneumonitis was 23.1%, the incidence of radiation esophagitis was 5.1%, and 2 patients experienced high-grade pneumonitis. Primary liver metastasis was a predictor of poor OS and PFS. Patients who received consolidative TRT after chemo-immunotherapy experienced more benefit than those who received TRT as palliative or salvage treatment for superior vena cava syndrome or disease progression. Conclusions: TRT is a feasible treatment for patients who receive chemo-immunotherapy for the management of ES-SCLC in consideration of its considerable efficacy and tolerable safety risk. This treatment is especially useful for patients without primary liver metastasis and who receive consolidative TRT after chemo-immunotherapy. Large-scale prospective studies are needed to confirm the efficacy and safety of this treatment modality.

The efficacy of thoracic radiotherapy in extensive stage small cell lung cancer with baseline brain metastases: a multi-institutional retrospective cohort study.

Background: Thoracic radiotherapy (TRT) had been shown to improve overall survival (OS) in extensive-stage small cell lung cancer (ES-SCLC) patients. However, approximately one fourth of SCLC harbored baseline brain metastases (BMs) and were excluded from previous TRT trials. Thus, the role of TRT in this sub-cohort of ES-SCLC requires elucidation. In this study, we evaluated the efficacy of TRT in ES-SCLC patients with clinically controlled baseline BMs. Methods: In this retrospective, multi-institutional cohort study, 49 patients fully staged as ES-SCLC with baseline BM, had their disease controlled at all sites with no BM symptoms for three months since treatment initiation were included. The patients were allocated to TRT or no-TRT groups according to whether they received consolidative TRT before progression. Their baseline characteristics were compared using the χ2 test. OS was selected as the primary observational endpoint. Survival and the incidence of cumulative progression between the groups were compared using log-rank analysis, and the interaction between TRT and selected factors was assessed via Cox proportional hazard analysis. Subgroup analysis was performed in oligo-metastasis patients (defined as five or fewer metastatic lesions in two or fewer organs). Results: Seventeen (34.7%) patients received TRT, with a median dose of 54 Gy. The failure pattern analysis revealed initial intrathoracic progression in 31.3% and 66.7% of patients in the TRT no-TRT groups, respectively. Also, the TRT group had a significantly longer OS than the no-TRT group [hazard ratio (HR) 0.426, P=0.011]. Clinical covariates including age, gender, performance status, smoking, metastatic state, response after chemotherapy, and TRT, were included in multivariate regression analysis. TRT remained significantly correlated with better OS (HR 0.430, P=0.029). Twenty-three (46.9%) patients had oligo-metastasis at baseline. Subgroup analyses showed that TRT was significantly correlated with better OS in oligo-metastatic patients but not in non-oligo metastatic patients. Conclusions: TRT improved the prognosis of select ES-SCLC patients with baseline BMs and should be considered in this sub-cohort, which has not been covered by previous randomized trials.

Real-World Efficacy and Safety of Thoracic Radiotherapy after First-Line Chemo-Immunotherapy in Extensive-Stage Small-Cell Lung Cancer.

(1) Background: At present, the efficacy and safety of thoracic radiotherapy (TRT) after chemo-immunotherapy (CT-IT) in patients with extensive-stage small-cell lung cancer (ES-SCLC) still remain unclear. The purpose of this study was to evaluate the role of TRT after CT-IT in patients with ES-SCLC. (2) Methods: From January 2020 to October 2021, patients with ES-SCLC treated with first-line anti-PD-L1 antibody plus platinum-etoposide chemotherapy were enrolled retrospectively. The survival data and adverse events data of patients treated with or without TRT after CT-IT were collected for analysis. (3) Results: A total of 118 patients with ES-SCLC treated with first-line CT-IT were retrospectively enrolled, with 45 patients with TRT and 73 patients without TRT after CT-IT. The median PFS and OS in the CT-IT + TRT group and CT-IT only group were 8.0 months versus 5.9 months (HR = 0.64, p = 0.025) and 22.7 months versus 14.7 months (HR = 0.52, p = 0.015), respectively. The median PFS and OS in all 118 patients treated with first-line CT-IT were 7.2 and 19.8 months with an ORR of 72.0%. In multivariate analyses, liver metastasis and response to CT-IT were shown to be independent prognostic factors of PFS (p < 0.05), while liver metastasis and bone metastasis were independent predictive factors of OS (p < 0.05). Although TRT was significantly associated with better PFS and OS in univariate analysis, the association of TRT and OS failed to reach statistical significance (HR = 0.564, p = 0.052) in multivariate analysis. There was no significant difference in adverse events (AEs) between two treatment groups (p = 0.58). (4) Conclusions: ES-SCLC patients treated with TRT after first-line CT-IT had prolonged PFS and OS with an acceptable safety profile. Further prospective randomized studies are necessary to explore the efficacy and safety of this treatment modality for ES-SCLC in future.

Safety of thoracic radiotherapy after PD-(L)1 inhibitor treatment in patients with lung cancer.

BACKGROUND: The safety of thoracic radiotherapy (TRT) after programmed death 1/programmed death ligand 1 (PD-(L)1) inhibitor treatment in patients with lung cancer was scarcely reported. This retrospective study was conducted to evaluate the incidence, severity, and risk factors of symptomatic treatment-related pneumonitis in patients with lung cancer who received this sequential combination. METHODS: We conducted a retrospective study of a cohort of patients with lung cancer who received TRT after at least two cycles of PD-(L)1 inhibitor treatment between January 2018 and August 2020. Treatment-related pneumonitis was evaluated and analyzed to illustrate the safety profile of this sequential combination. Potential risk factors were explored by univariate and multivariate logistic regression analyses. RESULTS: Among the 828 patients with prior PD-(L)1 inhibitor treatment, 96 patients receiving subsequent TRT were included in the analysis. Of these, 49 patients (51%) received radical TRT while 47 patients (49%) received palliative TRT. The median total dose was 52 Gy (IQR 50-60 Gy). The median time from the initiation of PD-(L)1 inhibitor treatment to TRT was 4.8 months (1.6-14.1 months) with most of the patients (74%) administering no less than four cycles of PD-(L)1 inhibitor. During follow-up, 47 patients (48.96%) developed symptomatic treatment-related pneumonitis (grade 2 n = 28, grade ≥3 n = 19) while six patients (6.25%) suffered from fatal toxicity. The median time of pneumonitis onset after completion of TRT was 35 days (0-177 days) with six patients developing during TRT. Pulmonary emphysema and lung V20 were demonstrated to be independent risk factors of symptomatic pneumonitis (OR: 5.67, 95% CI: 1.66-19.37, p = 0.006; OR: 3.49, 95% CI: 1.41-8.66, p = 0.007, respectively). CONCLUSION: TRT after PD-(L)1 inhibitor treatment resulted in significantly increased incidence and severity of treatment-related pneumonitis in patients with lung cancer. Intensive attention should be emphasized to the safety of this sequential combination in clinical practice.

Role of thoracic radiotherapy in extensive stage small cell lung cancer: a systemic review and meta-analysis.

BACKGROUND: The role of thoracic consolidation radiotherapy in patients with extensive stage small cell lung cancer (ES-SCLC) remains controversial. This study aimed to evaluate the efficacy of thoracic radiotherapy (TRT) in these patients. METHODS: A systematic literature search was performed in PubMed, Embase, and the Cochrane library to identify qualified clinical studies. The hazard ratios (HRs) and 95% confidence intervals (CIs) of overall survival (OS), progression-free survival (PFS) and local recurrence-free survival (LRFS) were extracted, and toxicity of the TRT group versus non-TRT group was analyzed. RESULTS: A total of 12 studies were included in this meta-analysis, including 936 patients in the TRT group and 1,059 patients in the non-TRT group. The combined results showed that TRT significantly improved OS (HR =0.65; 95% CI: 0.55-0.77, P<0.00001), PFS (HR =0.64; 95% CI: 0.56-0.72, P<0.00001) and LRFS (HR =0.38, 95% CI: 0.26-0.53, P<0.00001). Subgroup analysis showed that OS benefits were observed in patients receiving sequential TRT (HR =0.67; 95% CI: 0.54-0.84, P=0.0006). The addition of TRT significantly improved OS in patients over 65 years of age (HR =0.55; 95% CI: 0.40-0.74, P=0.0001). For patients with only one organ metastasis, there was no significant difference in OS between the two groups (HR =0.61; 95% CI: 0.36-1.01, P=0.06). There was no statistical difference in hematologic toxicity (leukopenia, thrombocytopenia, anemia) and non-hematologic toxicity (nausea or vomiting) between the two groups. The incidence of grade ≥3 esophageal toxicity was 4.6% in the TRT group and 0% in the non-TRT group (P=0.0001). Grade ≥3 bronchopulmonary toxicity was 2.9% in the TRT group and 0.8% in the non-TRT group (P=0.02). CONCLUSIONS: TRT improves OS, PFS and LRFS in patients with ES-SCLC, with a low increase in esophageal and bronchopulmonary toxicity. More randomized controlled trials (RCTs) are expected to confirm our conclusions. PROSPERO REGISTRATION NUMBER: CRD42020190575.

A nomogram to predict the overall survival of patients with symptomatic extensive-stage small cell lung cancer treated with thoracic radiotherapy.

BACKGROUND: Small cell lung cancer (SCLC) makes up 13% of lung malignancies. Only one-third of SCLC patients received their diagnosis at the limited stage. Treatment for symptomatic extensive-stage (ES) SCLC with persistent intrathoracic disease is still controversial. The present research aimed to analyze the impact of palliative thoracic radiotherapy (TRT) as a treatment for this patient group and build a prognostic nomogram. METHODS: In this retrospective, multi-center study, we analyzed 120 patients with ES-SCLC and a World Health Organization performance status of 1-2 who were diagnosed between March 2014 and September 2019. A nomogram was formulated to predict the patients' 1- and 2-year overall survival (OS). RESULTS: The study cohort had a median age of 62 years, and males accounted for 85% of enrollees. A significant extension was observed in the median OS in the TRT group compared to the no TRT group (P<0.001). When the patients were stratified by TRT dose, no significant differences in OS were noted (P=0.530). However, higher levels of inflammatory markers prior to TRT were associated with a shorter OS (neutrophil-to-lymphocyte ratio, P=0.002; platelet/lymphocyte ratio, P=0.023). The nomogram's Harrell's concordance (C)-statistic reached 0.70, and the calibration curve analysis revealed goodness of fit. CONCLUSIONS: The neutrophil-to-lymphocyte ratio is an independent factor predicting survival in ES-SCLC patients treated with palliative TRT. Our nomogram, which incorporates immunological markers, has higher accuracy than existing models for the prediction of individuals' chances of survival, and it could be a significant tool for clinicians in the development of tailored therapeutic strategies.

Organizing pneumonia after thoracic radiotherapy followed by anti-PD-1 antibody treatment for patients with lung cancer: Three case reports.

Anti-PD-1 antibodies and thoracic radiation therapy (TRT) generate adverse events, including pneumonitis. However, there is limited information about potential overlapping toxicity of anti-PD-1 antibodies administered after TRT. Herein, we report three cases. The first case was of a man in his 80s with squamous cell lung cancer (cT2aN0M0 stage IB). Twelve months after TRT, tumor regrowth was observed, and the patient was administered nivolumab. Twenty-four months after TRT, computed tomography (CT) showed organizing pneumonia (OP). The second case was of a man in his 70s with squamous cell lung cancer. He underwent surgery for pT3N1M0 stage IIIA; however, mediastinum lymph node metastasis developed. Therefore, he received TRT for the mediastinum lymph node metastasis. One month after the completion of TRT, nivolumab was administered. Two months after TRT, an OP diagnosis was made. The third case was of a man in his 60s with an unknown type of lung cancer. He received TRT for cT4N2M0 stage IIIB. Fourteen months after TRT, tumor regrowth was observed, thus, nivolumab was administered. Twenty-seven months after TRT, an OP diagnosis was made. These case reports draw attention to OP after TRT and anti-PD-1 antibody administration despite low V20. Careful follow-up of such patients is advised considering synergistic adverse events.

Treatment outcomes of patients with small cell lung cancer without prophylactic cranial irradiation.

BACKGROUND: Prophylactic cranial irradiation (PCI) is indicated for limited disease (LD) in small cell lung cancer (SCLC) patients who achieve a complete or near-complete response; however, it is sometimes not administered because of possible adverse reactions or patient refusal. Here we assessed treatment outcomes among patients with SCLC who were not treated with PCI. METHODS: The medical records of 60 patients (45 men, 15 women; mean age, 68 years; age range, 51-82 years) with SCLC were retrospectively reviewed. The tumors were staged by TNM classification. Two, 2, 5, 4, 32, and 15 patients had stage IA, IB, IIA, IIB, IIIA, and IIIB tumors, respectively. The patients were treated with thoracic radiotherapy (TRT) and four courses of chemotherapy. RESULTS: Our subjects had a median survival of 25 months and 2- and 5-year survival rates of 52.6% and 25.3%, respectively. Univariate analysis revealed that the development of brain metastasis, performance status (PS), and T-stage were significant factors correlated with survival rate. Multivariate analysis identified only PS [hazard ratio (HR), 5.845, 95% confidence interval (CI), 2.333-14.63, P=0.002] and brain metastasis as independent prognostic variables (HR, 2.344, 95% CI, 1.071-5.128, P=0.033). CONCLUSIONS: The results of our study demonstrated that the outcomes of treatment without PCI were improved, as compared with those of previously published data. Our findings may be used as reference data when PCI cannot be performed.