OL Oncology Letters 1792-1074 1792-1082 D.A. Spandidos 10.3892/ol.2025.15264 OL-30-5-15264 Articles Meta-analysis of the efficacy and safety of thoracic radiotherapy for extensive-stage small cell lung cancer in the era of immunotherapy JiangMeiqiao 1 ShaoLihua 2 LongYuanzhaoyun 1 SunJinning 1 WeiShihong 1 2 School of Clinical Medicine, Gansu University of Chinese Medicine, Lanzhou, Gansu 730030, P.R. China Department of Radiotherapy, Gansu Provincial Cancer Hospital, Lanzhou, Gansu 730050, P.R. China Correspondence to: Professor Shihong Wei, Department of Radiotherapy, Gansu Provincial Cancer Hospital, 2 East Xiaoxihu Street, Lanzhou, Gansu 730050, P.R. China, E-mail: 18919168488@163.com 112025 09092025 30 5 518 15032025 16072025 Copyright: © 2025 Jiang et al. 2025 This is an open access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.

Synergistic antitumor effects of thoracic radiotherapy (TRT) are still debated due to conflicting clinical evidence. The aim of the present meta-analysis was to evaluate the efficacy and safety of chemo-immunotherapy combined with TRT in extensive-stage small cell lung cancer (ES-SCLC). CNKI, Wanfang, VIP, Pubmed, Embase and the Cochrane library were searched for published literature on chemo-immunotherapy combined with TRT for ES-SCLC between January 1, 2018, and March 4, 2024. After screening the studies and extracting data according to the inclusion criteria, Review Manager 5.4 and Stata 15 were used to assess the risk of bias of the studies and perform a meta-analysis of the data. A total of 19 relevant prospective and retrospective clinical research articles were included, involving 1,557 patients. The results of the meta-analysis demonstrated that, in terms of efficacy, chemo-immunotherapy combined with TRT significantly improves overall survival [OS; hazard ratio (HR)=0.49; 95% confidence interval, (CI), 0.34–0.71; P<0.05] and progression-free survival (PFS; HR=0.62; 95% CI, 0.51–0.76; P<0.05) of patients with ES-SCLC. Sub-group analysis indicated that primary liver metastasis was an independent predictor of poor OS (HR=2.45; 95% CI, 1.84–3.25; P<0.05), and TRT was a favorable predictor of OS (HR=0.44; 95% CI, 0.21–0.96; P<0.05) and PFS (HR=0.59; 95% CI, 0.47–0.76; P<0.05). In terms of safety, the incidence of grade ≥3 adverse reactions in the chemo-immunotherapy/TRT combination group was significantly higher than that in the chemo-immunotherapy group (risk ratio=1.30; 95% CI, 1.02–1.66; P<0.05). The most common adverse reactions in the chemo-immunotherapy/TRT combination group were radiation pneumonitis (27%; 95% CI, 14–41%), radiation esophagitis (17%; 95% CI, 9–25%) and thrombocytopenia (9%; 95% CI, 5–14%). In conclusion, chemo-immunotherapy combined with TRT demonstrated improved survival outcomes in patients with ES-SCLC, with acceptable toxicity profiles. However, further validation through prospective clinical trials is warranted.

 chemotherapy immunotherapy thoracic radiotherapy extensive-stage small-cell lung cancer liver neoplasms meta-analysis Health Industry Research Program of Gansu Province GSWSKY2021-057 Lanzhou City Talent Innovation and Entrepreneurship Project 2021-RC-130 Gansu Provincial Key Talent Program 2024RCXM17 The present study was supported by the Health Industry Research Program of Gansu Province (grant no. GSWSKY2021-057), the Lanzhou City Talent Innovation and Entrepreneurship Project (grant no. 2021-RC-130) and the Gansu Provincial Key Talent Program (grant no. 2024RCXM17). Introduction

Small cell lung cancer (SCLC) accounts for 13–15% of all lung cancers, of which 65–70% are extensive-stage (ES)-SCLC, which has a high degree of malignancy and poor prognosis, with a 5-year survival rate of 5–7% (1). Over the past few decades, platinum-based chemotherapy has been the standard treatment for ES-SCLC, with a median survival of 8.8–10.4 months (2). However, there have been notable breakthroughs in immunotherapy for ES-SCLC. For example, the IMpower133 study reported that the addition of atezolizumab [a programmed death-ligand 1 (PD-L1) inhibitor] to chemotherapy as a first-line treatment improved the overall survival (OS) and progression-free survival (PFS) of patients with ES-SCLC, and enhanced the quality of life of patients (3,4). The Caspian study reported that chemotherapy combined with durvalumab (a PD-L1 inhibitor) for untreated patients could increase OS by 2–3 months (5,6). The Astrum-005 study reported that chemotherapy combined with toripalimab for ES-SCLC could increase OS to 15.4 months (7). However, these studies did not combine chemotherapy with thoracic radiotherapy (TRT). The trial data from the study by Kim et al (8) identified intrathoracic progression as the predominant pattern of treatment failure following first-line chemo-immunotherapy in ES-SCLC. Moreover, the study by Jeremic et al (9) reported that chemo-radiotherapy had a synergistic antitumor effect in the treatment of ES-SCLC. The CREST and RTOG 0937 studies further reported that, as compared with chemotherapy alone, the addition of TRT in the treatment plan improved the survival advantage of patients with ES-SCLC (9–11). Therefore, whether TRT is associated with positive synergistic antitumor effects in the era of chemo-radiotherapy warrants further discussion.

The present study performed a systematic review and meta-analysis evaluating the efficacy and safety profile of chemo-immunotherapy with and without concurrent TRT in patients with ES-SCLC.

 Materials and methods <sec> <title>Data search

A systematic literature search was performed across six databases (PubMed (https://pubmed.ncbi.nlm.nih.gov/), Embase (https://www.embase.com/), Cochrane Library (https://www.cochranelibrary.com/), China National Knowledge Infrastructure (https://www.cnki.net/), Wanfang (https://www.wanfangdata.com.cn/) and Chongqing VIP Information Database (https://www.cqvip.com/) between January 1, 2018, and March 4, 2024. The search strategy incorporated controlled vocabulary and keywords including: ‘PD-L1’, ‘PD-1’, ‘radiotherapy’, ‘chemo-immunotherapy’, ‘ES-SCLC’, ‘immunotherapy’, ‘chemotherapy’ and ‘extensive-stage small cell lung cancer’. This retrieval process was independently performed by two investigators.

 Inclusion and exclusion criteria for studies

The inclusion criteria were as follows: i) Patients diagnosed with ES-SCLC through cytology or histology; ii) patients treated with chemo-immunotherapy combined with TRT; iii) outcome measures including OS, PFS, objective response rate and adverse events (AE); and iv) complete, accurate and reliable data. Moreover, the exclusion criteria were as follows: i) Reviews, protocols, meta-analyses or letters; ii) republished articles without new data; and iii) studies that reported outcomes but withheld raw data or had incomplete information.

 Literature screening and data extraction

A total of two researchers independently performed article screening and data extraction, employing cross-verification protocols to resolve interpretive discrepancies. The extracted information included the following: Article title; first author; publication year; clinical trial phase; study protocol; characteristics of the subjects included in the study and control groups; sample size; primary outcome measures; and secondary outcome measures.

 Quality assessment of literature and sensitivity analysis

Literature types included in the present study consisted of cohort and single-arm studies. For cohort studies, the quality assessment was performed using the Newcastle-Ottawa Scale (12). For single-arm studies, the Methodological Index for Non-Randomized Studies criteria were applied for evaluation (13).

Furthermore, to assess the robustness of the results, a sensitivity analysis was performed by individually excluding each trial to evaluate its impact on the overall outcomes. If the outcome measure included ≥10 articles, a funnel plot was used to assess publication bias.

 Data synthesis and statistical analysis

The proportion of each endpoint with its corresponding 95% confidence interval (CI) was pooled for each single-arm study and visualized using forest plots. For each dual-arm study, the hazard ratio (HR) or risk ratio (RR) with corresponding 95% CIs were calculated. In accordance with recommendation outlines in the Cochrane Handbook for Systematic Reviews of Interventions (14), all meta-analyses were performed using a random-effects model. This approach was employed to explicitly account for the anticipated heterogeneity in intervention effects attributable to variations across distinct study populations and geographical settings. Sequential trial exclusion was used in sensitivity analyses to assess the influence of individual studies on the pooled outcomes. Publication bias was additionally evaluated through funnel plot analysis. The statistical analyses were performed using Stata 15 software (StataCorp LP) with Review Manager 5.4 (The Cochrane Collaboration).

 Results <sec> <title>Literature screening and baseline characteristics

A total of 4,682 studies were initially screened for inclusion. Following the removal of duplicates and the exclusion of studies that were deemed irrelevant based on their titles and abstracts, a total of 4,571 studies were discarded. The remaining 111 studies were subjected to a thorough review. A total of 92 studies were excluded as they did not meet the predefined eligibility criteria. Ultimately, 19 studies were selected for analysis, which included 10 two-arm cohort studies and 9 single-arm studies, involving 1,577 eligible patients. The experimental group in all studies received chemo-immunotherapy combined with TRT, and the control group received either chemotherapy alone or chemo-immunotherapy. The literature screening process is presented in Fig. S1 and the basic characteristics of the included studies are presented in Table I. All included studies were considered to be of moderate-to-high quality (Tables SI and SII).

 Overall outcomes

Chemo-immunotherapy with vs. without TRT was evaluated for efficacy and safety in ES-SCLC in the present meta-analysis. The combined approach was associated with significantly improved survival rates compared with chemo-immunotherapy alone. Specifically, chemo-immunotherapy with TRT was significantly associated with improved PFS (0.62; 95% CI, 0.51–0.76; Fig. 1) and OS (0.49; 95% CI, 0.34–0.71; Fig. 2), compared with chemo-immunotherapy alone. This indicated a significant clinical benefit from chemo-immunotherapy combined with TRT. Moreover, pooled analysis of specific survival data from patients with ES-SCLC receiving chemo-immunotherapy combined with TRT demonstrated significantly improved therapeutic outcomes. The pooled 6-month OS was 0.92 (95% CI, 0.86–0.98), the 1-year OS was 0.72 (95% CI, 0.62–0.81) and the 18-month OS was 0.58 (95% CI, 0.43–0.73). Furthermore, the pooled 6-month PFS was 0.70 (95% CI, 0.54–0.85) and the 1-year was PFS 0.39 (95% CI, 0.27–0.51) (Table II).

 Increased incidence of grade ≥3 AEs with combined therapy

A total of seven included studies provided data on the incidence of grade ≥3 AEs. The results revealed that the incidence of grade ≥3 AEs in the group receiving chemo-immunotherapy combined with TRT was significantly higher than that in the group receiving chemo-immunotherapy alone (RR=1.30; 95% CI, 1.02–1.66; P<0.05), indicating that the combined treatment had no significant impact (Fig. 3). Additionally, the results demonstrated that the AEs with the highest incidence rates in the combined treatment were radiation pneumonitis (27%; 95% CI, 14–41%; Fig. 4), radiation esophagitis (17%; 95% CI, 9–25%; Fig. 5) and thrombocytopenia (9%; 95% CI, 5–14%; Fig. 6).

 Survival disparities in prespecified subgroups

Subgroup analyses were additionally performed to assess the effects of pre-specified variables on OS and PFS. The meta-analysis demonstrated that patients with ES-SCLC with baseline liver metastases had significantly worse OS compared with patients without liver metastases (HR=2.45; 95% CI, 1.84–3.25; P<0.05; Fig. 7). Additionally, patients not receiving TRT had significantly reduced OS (HR=0.44; 95% CI, 0.21–0.96; P<0.05) and PFS (HR=0.59; 95% CI, 0.47–0.76; P<0.05) compared with TRT-treated patients (Fig. 8).

 Bias and sensitivity analyses

Concurrently, a publication bias assessment and sensitivity analysis were performed. Most included studies exhibited a moderate risk-of-bias, primarily attributable to their retrospective observational design (Fig. 9). Furthermore, sensitivity analysis revealed instability in the pooled OS results. The exclusion of the study by Wu et al (15) significantly reduced heterogeneity (P=0.42; I2=0%), whilst the pooled effect size remained statistically significant (P<0.05) with unchanged overall conclusions (Fig. 10). All other outcome measures demonstrated robust consistency.

 Discussion

According to data from the American Cancer Center, lung cancer has a high incidence and mortality rate, ranking at the forefront among all cancers (16). SCLC is an aggressive high-grade neuroendocrine malignancy with a high potential for metastasis and a poor clinical prognosis. A total of ~70% of patients are diagnosed with ES-SCLC at the time of initial diagnosis (17,18).

Immunotherapy has made rapid progress in the field of ES-SCLC, establishing a first-line treatment position (19). However, the application of radiotherapy in ES-SCLC is relatively limited, with controversies surrounding the target population, dose fractionation and timing of its addition. Radiotherapy serves an important role in the comprehensive treatment of SCLC (20). The phase 3 randomized controlled trial by Slotman et al (11) demonstrated that consolidative TRT for patients who respond to systemic therapy has survival benefits. However, in studies such as IMpower133 and CASPIAN, TRT was not included in the treatment regimen (3,6). In the era of immunotherapy, the value of TRT remains controversial. Therefore, the aim of the present study was to further assess the efficacy and safety of adding TRT to ES-SCLC.

The present meta-analysis included 19 relevant studies to evaluate the efficacy and safety of the chemo-immunotherapy combined with TRT regimen for the treatment of ES-SCLC. The study results indicated that, compared with chemo-immunotherapy alone, the combination with TRT significantly prolonged OS and PFS, and was tolerable with controllable safety. In clinical practice, the safety of treatment methods has always been a matter of great concern. The results of the present meta-analysis revealed a statistically significant increase in grade ≥3 treatment-related AEs with chemo-immunotherapy + TRT (RR=1.30; 95% CI, 1.02–1.65; P<0.05). Moreover, whilst the adverse reactions were manageable in most cases, radiotherapy-related complications may occur after TRT, such as radiation-induced lung injury, radiation esophagitis and hematological toxicity. In patients receiving chemo-immunotherapy combined with TRT, clinicians should carefully differentiate between radiation-induced lung injury and immune-related pneumonia, to take appropriate treatment measures in a timely manner (21).

Notably, among the literature included in the present study, three studies (22–24) reported outcomes of local PFS (LPFS) and distant PFS (DPFS). Although the data presentation varied and could not be pooled for analysis, they still indicated a trend that chemo-immunotherapy combined with TRT is beneficial for LPFS and DPFS (Table III). The present meta-analysis combined the multivariate analyses of OS and PFS-related factors from each group of studies. The results revealed that primary liver metastasis is a risk factor affecting patient OS (HR=2.45; 95% CI, 1.84–3.25; P<0.05). This may be because liver metastasis weakens the systemic efficacy of immunotherapy through macrophage-mediated T-cell clearance (25,26). In liver metastases, multiple stromal cells act synergistically to induce the generation of regulatory T cells, promote T cell apoptosis and depletion, inhibit antigen presentation, release immunosuppressive factors and remodel metabolism, thereby creating a profoundly immunosuppressive microenvironment that markedly restricts effector T cell activity, leading to peripheral immune tolerance (27). By contrast, TRT is a favorable factor for improving the prognosis of patients with ES-SCLC. This is likely due to thoracic tumor progression being the main cause of death in ES-SCLC (8). Even after receiving standard systemic treatment, 75–90% of patients still have residual thoracic lesions, and ≤90% of patients experience intrathoracic progression within 1 year from diagnosis (28). However, TRT is still considered an effective treatment strategy for local-regional control (8).

However, the present study had the following limitations: i) The 19 included articles were actually 8 single-arm studies, 10 two-arm studies and 1 three-group study. However, only data on chemo-immunotherapy combined with TRT and chemo-immunotherapy alone was extracted. This may lead to inconsistent comparator groups across studies; ii) the 19 included articles contained a small amount of data; a small sample size reduces statistical power, and small-sample data are susceptible to influence from extreme values or random effects, which could potentially influence the results of the meta-analysis; iii) it is currently unclear what the indications are for TRT in ES-SCLC, and there is uncertainty about whether the most suitable patient population was selected for the study; and iv) the baseline characteristics of the trials included in the present study varied, and the treatment protocols differed, which may have affected the final results.

In summary, TRT, as an effective means of local tumor control, has demonstrated good efficacy for patients with ES-SCLC in the current therapeutic landscape where immunotherapy is integrated into systemic treatment, with controllable safety. The combination of chemo-radiotherapy with TRT can enhance the survival rate of patients with ES-SCLC, demonstrating favorable outcomes, and the treatment is well-tolerated by patients, with manageable AEs. However, more large-scale prospective randomized controlled clinical trials are required to assess the optimal application strategy of TRT in the treatment of ES-SCLC. This includes determining the optimum timing for the introduction of TRT, the radiation dose and the fractionation mode. In addition, research should further explore how to effectively screen the beneficiary population to ensure the maximization of treatment benefits.

 Supplementary Material Supporting Data Supporting Data Acknowledgements

Not applicable.

 Availability of data and materials

The data generated in the present study may be requested from the corresponding author.

 Authors' contributions

MJ performed data collection, statistical analysis and manuscript writing. LS contributed to data collection and manuscript revision. YL and JS were responsible for data acquisition, analysis and interpretation, and confirm the authenticity of all the raw data. SW interpreted data and designed the study. All authors critically reviewed the manuscript. All authors read and approved the final manuscript.

 Ethics approval and consent to participate

Not applicable.

 Patient consent for publication

Not applicable.

 Competing interests

The authors declare that they have no competing interests.

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Median progression-free survival in comparative studies. CI, confidence interval; SE, standard error.

Figure 1. Median progression–free survival in comparative studies. CI, confidence interval; SE, standard error.

Median overall survival in comparative studies. CI, confidence interval; SE, standard error.

Figure 2. Median overall survival in comparative studies. CI, confidence interval; SE, standard error.

Treatment-related advert events of ≥3 grade in comparative studies. CI, confidence interval. M-H, mantel-haenszel.

Figure 3. Treatment–related advert events of ≥3 grade in comparative studies. CI, confidence interval. M–H, mantel–haenszel.

Pooled rate of radiation pneumonitis. CI, confidence interval; ES, effect size.

Figure 4. Pooled rate of radiation pneumonitis. CI, confidence interval; ES, effect size.

Pooled rate of radiation esophagitis. CI, confidence interval; ES, effect size.

Figure 5. Pooled rate of radiation esophagitis. CI, confidence interval; ES, effect size.

Pooled rate of thrombocytopenia. CI, confidence interval; ES, effect size.

Figure 6. Pooled rate of thrombocytopenia. CI, confidence interval; ES, effect size.

Comparative study of overall survival in patients with or without primary liver metastasis. CI, confidence interval; SE, standard error.

Figure 7. Comparative study of overall survival in patients with or without primary liver metastasis. CI, confidence interval; SE, standard error.

Comparative study of OS and PFS in patients with or without TRT. OS, overall survival; PFS, progression-free survival; TRT, thoracic radiotherapy; CI, confidence interval; SE, standard error.

Figure 8. Comparative study of OS and PFS in patients with or without TRT. OS, overall survival; PFS, progression–free survival; TRT, thoracic radiotherapy; CI, confidence interval; SE, standard error...

Funnel plot for overall survival. SE, standard error.

Figure 9. Funnel plot for overall survival. SE, standard error.

Sensitivity analysis. (A) Scatter plot for sensitivity analysis of OS. (B) Forest map of sensitivity analysis of OS. OS, overall survival; CI, confidence interval; SE, standard error.

Figure 10. Sensitivity analysis. (A) Scatter plot for sensitivity analysis of OS. (B) Forest map of sensitivity analysis of OS. OS, overall survival; CI, confidence interval; SE, standard error.

Main characteristics of the studies included in the present meta-analysis.

Median age (low-high) Sex (female/male)
First author/s, year Study type TRT Non-TRT TRT Non-TRT Sample size (systemic therapy/control) Systemic therapy Control Dose of CTRT Outcome index (Refs.)
Kim et al, 2024 Retrospective 7/32 10/62 41 (6/35) Chemo + atezolizumab + CTRT Chemo + atezolizumab 52–66 Gy (5 patients), 24 Gy (1 patient) OS, IPFS (8)
Wu et al, 2022 Retrospective 64 (51–90) 1/10 2/9 22 (11/11) Chemo + atezolizumab/durvalumab + CTRT Chemo + atezolizumab/durvalumab 28–64 Gy PFS, OS (15)
Diamond et al, 2022 Retrospective 66 (58–74) 20 Chemo + atezolizumab + CTRT 30–60 Gy PFS, OS, LPFS, DPFS, AEs (22)
Fang et al, 2023 Retrospective 62 (58–68) 64 (61–70) 3/36 5/68 111 (39/62) Chemo + ICI + CTRT Chemo + ICI 30–60 Gy PFS, OS, (23)
Li et al, 2023 Retrospective 59 (52–65) 63 (56–67) 10/37 6/47 100 (47/53) Chemo + ICI + CTRT 45–54 Gy PFS, OS, LRFS (24)
Perez et al, 2021 Prospective 66 (45–77) 21 Chemo + ipilimumab + nivolumab + CTRT 3 Gy /10 f PFS, OS, irAE (29)
Longo et al, 2024 Retrospective 64 (60–69) 71 (65–75) 26/33 22/37 120 (59/61) Chemo + atezolizumab/ durvalumab + CTRT Chemo + atezolizumab/ durvalumab 30–60 Gy PFS, OS, AEs (30)
Yao et al, 2024 Retrospective 21/78 17/81 197 (99/98) Chemo + ICI + CTRT Chemo + ICI 30–60 Gy PFS, OS, AEs (31)
Li et al, 2023 Retrospective 63 (35–84) 2/31 36 Chemo + atezolizumab/ durvalumab + CTRT 52–113 Gy PFS, OS, AEs (32)
Hoffmann et al, 2023 Retrospective 19/22 41 (23/18) Chemo + atezolizumab/durvalumab + CTRT Chemo + atezolizumab/ durvalumab 3 Gy/10 f OS (33)
Welsh et al, 2020 Prospective 62 (37–80) 13/20 33 Chemo + pembrolizumab + CTRT 45 Gy PFS, OS, AEs (34)
Xie et al, 2023 Retrospective 62 (45–79) 63 (45–90) 10/35 12/61 118 (45/73) Chemo + ICI + CTRT Chemo + ICI 30–60 Gy PFS, OS, AEs (35)
Peng et al, 2023 Retrospective 63 (56–69) 61 (55–66) 14/43 13/44 114 (57/57) Chemo + atezolizumab/durvalumab + CTRT Chemo + atezolizumab/ durvalumab 30–60 Gy PFS, OS, AEs (36)
Liu et al, 2022 Retrospective 62 (52–73) 3/8 11 Chemo + atezolizumab/toripalimab + CTRT 30–60 Gy/10–30 f PFS, OS, AEs (37)
Chen et al, 2022 Prospective 64 (37–75) 6/25 31 Chemo + SHR-1316 + CTRT 3 Gy/10 f or ≥2 Gy PFS, OS, AEs (38)
Gross et al, 2021 Retrospective 65 (40–90) 244 (63/181) Chemo + ICI + CTRT Chemo + ICI OS (39)
Daher et al, 2022 Retrospective 63 66 8/17 30/71 126 (25/101) Chemo + atezolizumab/durvalumab + CTRT Chemo + atezolizumab/durvalumab 24–60 Gy PFS, OS, AEs (40)
Cai et al, 2023 Retrospective 41 (38–79) 12/66 78 Chemo + ICI + CTRT PFS, OS, ORR, DCR, AEs (41)
Meng et al, 2024 Retrospective 66 (50–79) 6/27 33 Chemo + atezolizumab/durvalumab/PD-1 + CTRT 40 (24–60) Gy PFS, OS, AEs (42)

Chemo, chemotherapy; TRT, thoracic radiotherapy; CTRT, consolidative thoracic radiotherapy; PFS, progression-free survival; OS, overall survival; AE, adverse event; irAE, immune-related AE; LPFS, local PFS; DPFS, distant PFS; IPFS, intrathoracic progression-free survival; ICI, immune checkpoint inhibitor; ORR, objective response rate; DCR, disease control rate.

Summary analysis of survival time of patients receiving chemo-immunotherapy combined with thoracic radiotherapy.

Survival HR 95% CI I2, % P-value (Refs.)
OS
  6-month 0.92 0.86–0.98 58.60 0.046 (22,32,34,41,42)
  1-year 0.72 0.62–0.81 85.20 <0.001 (22–24,29–33,35,36,41)
  18-month 0.58 0.43–0.73 71.00 0.032 (23,24,36)
PFS
  6-month 0.70 0.54–0.85 93.20 <0.001 (23,29,32,34–36,41)
  1-year 0.39 0.27–0.51 86.00 <0.001 (23,30–32,35,36,41)

HR, hazard ratio; CI, confidence interval; OS, overall survival; PFS, progression-free survival.

Analysis of LPFS and DPFS in patients treated with chemo-immunotherapy combined with thoracic radiotherapy.

A, LPFS
First author/s, year Median LPFS, HR (95% CI; P-value) (Refs)
Diamond et al, 2022 11.4 months (95% CI, 8.5–14.2; P<0.05) (22)
  6-month 94.70%
  12-month 46.20%
Fang et al, 2023 HR 0.30 (95% CI, 0.16–0.56; P<0.05) (23)
Li et al, 2023 HR 0.27 (95% CI, 0.13–0.53; P<0.05) (24)
B, DPFS
First author/s, year Median DPFS (95% CI; P-value) (Refs)
Diamond et al, 2022 6.7 months (95% CI, 5.8–7.5; P<0.05) (22)
  6-month 73.90%
  12-month 14.10%

HR, hazard ratio; CI, confidence interval; LPFS, local progression free survival; DPFS, distant progression free survival.