Effects of brain radiotherapy strategies on survival in the era of MRI for patients with limited stage small cell lung cancer.

BACKGROUND AND PURPOSE: In the context of the widespread availability of magnetic resonance imaging (MRI) and aggressive salvage irradiation techniques, there has been controversy surrounding the use of prophylactic cranial irradiation (PCI) for small-cell lung cancer (SCLC) patients. This study aimed to explore whether regular brain MRI plus salvage brain irradiation (SBI) is not inferior to PCI in patients with limited-stage SCLC (LS-SCLC). METHODS: This real-world multicenter study, which was conducted between January 2014 and September 2020 at three general hospitals, involved patients with LS-SCLC who had a good response to initial chemoradiotherapy and no brain metastasis confirmed by MRI. Overall survival (OS) was compared between patients who did not receive PCI for various reasons but chose regular MRI surveillance and followed salvage brain irradiation (SBI) when brain metastasis was detected and patients who received PCI. RESULTS: 120 patients met the inclusion criteria. 55 patients received regular brain MRI plus SBI (SBI group) and 65 patients received PCI (PCI group). There was no statistically significant difference in median OS between the two groups (27.14 versus 33.00 months; P = 0.18). In the SBI group, 32 patients underwent whole brain radiotherapy and 23 patients underwent whole brain radiotherapy + simultaneous integrated boost. On multivariate analysis, only extracranial metastasis was independently associated with poor OS in the SBI group. CONCLUSION: The results of this real-world study showed that MRI surveillance plus SBI is not inferior to PCI in OS for LS-SCLC patients who had a good response to initial chemoradiotherapy.

Establishment of a prognostic nomogram for elderly patients with limited-stage small cell lung cancer receiving radiotherapy.

The present study explored the risk factors associated with radiotherapy in seniors diagnosed with limited-stage small cell lung cancer (LS-SCLC) to construct and validate a prognostic nomogram. The study retrospectively included 137 elderly patients with LS-SCLC who previously received radiotherapy. Univariate and multivariate COX analyses were conducted to identify independent risk factors and determine optimal cut-off values. Kaplan-Meier survival curves and nomograms were constructed to predict survival. Calibration and receiver operating characteristic (ROC) curves were used to evaluate the accuracy and consistency of the nomogram. Illness rating scale-geriatric (CIRS-G) score, treatment strategy, lymphocyte-to-monocyte ratio (LMR), white blood cell-to-monocyte ratio (WMR), and prognostic nutritional index (PNI) were discovered to be independent prognostic factors. Based on the findings of our multivariate analysis, a risk nomogram was developed to assess patient prognosis. Internal bootstrap resampling was utilized to validate the model, and while the accuracy of the AUC curve at 1 year was modest at 0.657 (95% CI 0.458-0.856), good results were achieved in predicting 3- and 5 year survival with AUCs of 0.757 (95% CI 0.670-0.843) and 0.768 (95% CI 0.643-0.893), respectively. Calibration curves for 1-, 3-, and 5 year overall survival probabilities demonstrated good cocsistency between expected and actual outcomes. Patients with concurrent chemoradiotherapy, CIRS-G score > 5 points and low PNI, WMR and LMR correlated with poor prognosis. The nomogram model developed based on these factors demonstrated good predictive performance and provides a simple, accessible, and practical tool for clinicians to guide clinical decision-making and study design.

Efficacy and safety of first-line PD-L1/PD-1 inhibitors in limited-stage small cell lung cancer: a multicenter propensity score matched retrospective study.

Background: The prognosis of small cell lung cancer (SCLC) patients is poor, and the standard first-line treatment for limited-stage small cell lung cancer (LS-SCLC) is still chemotherapy and thoracic radiotherapy. The primary objectives of our study were to confirm the superior efficacy of first-line immune checkpoint inhibitors (ICIs) plus etoposide and platinum (EP) for LS-SCLC and find crucial biomarkers. Methods: We analyzed LS-SCLC patients from three medical centers, employing propensity score matching for group comparability. Survival outcomes were estimated by Kaplan-Meier and Cox regression analyses. Additionally, we conducted univariate and multivariate analyses to investigate potential predictive factors. Results: Among 150 patients in our study, we successfully matched 41 pairs. The median overall survival (OS) was 29.5 months in the EP + ICIs group and 20.0 months in the EP group {hazard ratio (HR) =0.64 [95% confidence interval (CI): 0.41-1.02], P=0.059}. The median progression-free survival (PFS) was significantly extended in the EP + ICIs group (14.6 months), compared to the EP group (8.6 months) [HR =0.42 (95% CI: 0.28-0.63), P<0.001]. After matching, patients receiving chemo-immunotherapy had a median OS of 36.1 months, significantly surpassing those receiving chemotherapy alone (19.0 months) [HR =0.51 (95% CI: 0.28-0.93), P=0.02]. And the patients in the EP + ICIs group also had longer PFS after matching [HR =0.42 (95% CI: 0.25-0.71), P=0.001]. No significant difference in the objective response rate (ORR) and treatment-related adverse events (trAEs) between the two groups was found (ORR: EP: 81.0%, EP + ICIs: 90.0%, P=0.14; trAEs: EP: grade 1-2, 49.3%; grade 3-4, 42.5%; EP + ICIs: grade 1-2, 40.0%; grade 3-4, 49.1%, P=0.62). The multivariate analysis presented that the history of immunotherapy [EP + PD-1 inhibitors: HR =0.33 (95% CI: 0.17-0.62), P=0.001; EP + PD-L1 inhibitors: HR =0.18 (95% CI: 0.06-0.60), P=0.005] and baseline lung immune prognostic index (LIPI) [intermediate: HR =2.22 (95% CI: 1.20-4.13), P=0.01; poor: HR =2.03 (95% CI: 0.71-5.77), P=0.18] were independent prognostic factors for PFS among all LS-SCLC cases. However, no independent prognostic factor was identified for OS. Conclusions: Our real-world data showed promising clinical efficacy and tolerable safety of first-line programmed cell death protein 1 (PD-1) inhibitors or programmed cell death ligand 1 (PD-L1) inhibitors in cases with LS-SCLC. Additionally, LIPI may serve as a valuable prognostic factor.

Conditional Survival of Patients with Limited-Stage Small Cell Lung Cancer After Surgery: A National Real-World Cohort Study.

BACKGROUND: The prognosis of limited-stage small cell lung cancer (LS-SCLC) after surgery usually is estimated at diagnosis, but how the prognosis actually evolves over time for patients who survived for a predefined time is unknown. METHODS: Data on patients with a diagnosis of LS-SCLC after surgery between 2004 and 2015 were retrieved from the Surveillance, Epidemiology, and End Results (SEER) database. The 5-year conditional cancer-specific survival (CCSS) and conditional overall survival (COS) were calculated. RESULTS: This study analyzed 997 patients (555 women, 55.7%) with a median age, of 67 years (interquartile range [IQR], 60-73 years). The 5-year CCSS and COS increased from 44.7% and 38.3%, respectively, at diagnosis to 83.7% and 67.9% at 5 years after diagnosis. Although there were large differences with different stages (stages I, II, and III) at diagnosis (respectively 59.5%, 28.4%; 28.1% for CCSS and 50.6%, 24.8%, and 23.6% for COS), the gap decreased with time, and the rates were similar after 5 years (respectively 85.0%, 80.3%, and 79.4% for CCSS; 65.6%, 56.9%, and 61.3% for COS). The 5-year conditional survival for the patients who received lobectomy was better than for those who received sublobectomy or pneumonectomy. Multivariable analyses showed that only age and resection type were independent predictors for CCSS and COS, respectively, throughout the period. CONCLUSION: Conditional survival estimates for LS-SCLC generally increased over time, with the most significant improvement in patients with advanced stage of disease. Resection type and old age represented extremely important determinants of prognosis after a lengthy event-free follow-up period.

Application of postoperative adjuvant radiotherapy in limited-stage small cell lung cancer: A systematic review and meta-analysis.

BACKGROUND AND PURPOSE: One of the most important treatments for small cell lung cancer (SCLC) is radiation therapy. Currently, the criteria for administering postoperative adjuvant radiotherapy (PORT) in SCLC remain uncertain. Therefore, we conducted a meta-analysis to investigate the influence of PORT on the prognosis of limited-stage SCLC (LS-SCLC). METHODS: We conducted a comprehensive search across three databases, PubMed, Embase, and the Cochrane Library. Data analysis involved utilizing both random-effects and fixed-effects models for pooling the results. A comparative analysis was performed to assess the prognostic outcomes of patients with LS-SCLC who did and did not undergo PORT. The primary outcome assessed was overall survival (OS), while the secondary outcome was disease-free survival (DFS). RESULTS: This analysis included 11 retrospective studies comprising 7694 eligible participants. Among the entire population of LS-SCLC patients, the OS was superior in those receiving PORT than in those not receiving it (hazard ratio [HR]: 0.79, 95 % confidence interval [CI]: 0.71-0.87; P < 0.0001). In pN0 stage LS-SCLC patients, PORT was associated with a detrimental effect on OS (HR: 1.22, 95 % CI: 1.04-1.43; P = 0.01). In pN1 stage LS-SCLC patients, additionally administering PORT did not provide a significant OS advantage as compared to not administering it (HR: 0.82, 95 % CI: 0.60-1.12; P = 0.21). In pN2 stage LS-SCLC patients, those receiving PORT demonstrated a significant improvement in OS (HR: 0.59; 95 % CI: 0.50-0.70; P < 0.0001) as compared to those not receiving it. Regarding DFS in LS-SCLC patients, the difference in the protective effect with and without the administration of PORT was less pronounced (HR: 0.76, 95 % CI: 0.58-1.00; P = 0.053). CONCLUSIONS: With respect to OS, PORT is not advisable in patients with pN0 or pN1 stage LS-SCLC but is highly recommended in pN2 stage LS-SCLC. Further research is warranted to confirm these findings.

[Impact of the depth of remission by induction chemotherapy on the prognosis of limited stage small cell lung cancer].

Objective: To evaluate the effect of depth of remission of induction chemotherapy on the overall prognosis of limited stage small cell lung cancer (L-SCLC). Methods: The study was a retrospective, L-SCLC patients who contained complete imaging data and underwent consecutive standardized treatments at the Department of Thoracic Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University between January 2013 and June 2021 were included. To delineate the volume of tumor before and after induction chemotherapy and to calculate the depth of remission caused by the induced chemotherapy. The time receiver operating characteristic (timeROC) method was used to determine the optimal predictors for prognosis, multi-factor analysis using Cox risk proportional model. Results: A total of 104 patients were included in this study. The median PFS and OS of this cohort were 13.7 months and 20.9 months, respectively. It was observed by timeROC analysis that residual tumor volume after induction chemotherapy had the optimal predictive value of PFS at 1 year (AUC=0.86, 95% CI: 0.78~0.94) and OS at 2 years (AUC=0.76, 95% CI: 0.65~0.87). Multivariate analysis showed residual tumor volume after induction chemotherapy was the independent prognostic factor to PFS (HR=1.006, 95% CI: 1.003~1.009, P<0.01) and OS (HR=1.009, 95% CI: 1.005~1.012, P<0.001). For those whose residual tumor volume remitted to less than 10 cm(3) after induction chemotherapy, the favorable long-term outcomes could be achieved, regardless of their initial tumor load. Conclusion: The depth of remission of induction chemotherapy could be a promising prognostic predictor to the L-SCLC and provide the individualized treatment guidance.

Neutrophil-to-lymphocyte and platelet-to-lymphocyte ratios as prognostic biomarkers in limited-stage small-cell lung cancer: a meta-analysis.

Background: The role of neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) as prognostic markers in limited-stage small-cell lung cancer (LS-SCLC) remains controversial. Methods: Using pooled hazard ratios (HR) with 95% CIs, we assessed the correlation of pre-treatment NLR and PLR with overall survival (OS) and progression-free survival (PFS) in LS-SCLC. Publication bias was assessed by Begg's and Egger's tests. Results: Ten studies were enrolled in our meta-analysis. Pooled analyses showed that pre-treatment high NLR was significantly associated with poor OS (HR: 1.80) and PFS (HR: 1.69) in LS-SCLC patients. High pre-treatment PLR was also associated with shorter OS (HR: 1.52) and PFS (HR: 1.39) in LS-SCLC patients. Conclusion: Our meta-analysis suggests that high pre-treatment NLR or PLR may be negatively related to OS and PFS in LS-SCLC.

Prophylactic cranial irradiation-related lymphopenia affects survival in patients with limited-stage small cell lung cancer.

Background: The study aimed to identify the relations of the absolute lymphocyte count (ALC) nadir during prophylactic cranial irradiation (PCI) and patient outcomes in limited-stage small cell lung cancer (LS-SCLC). Methods: We analyzed 268 L S-SCLC patients who underwent PCI from 2012 to 2019. ALC values were collected prior, during, and 3 months post PCI. Kaplan-Meier and Cox regression analyses were performed to assess the relation of ALC to patient prognosis. Two nomograms were developed on the basis of clinical variables for survival prediction. Results: Compared with the ALC before PCI (1.13 × 109 cells/L), the ALC nadir during PCI was significantly reduced by 0.68 × 109 cells/L (P < 0.001) and raised to 1.02 × 109 cells/L 3 months post PCI. Patients with a low ALC nadir during PCI (<0.68 × 109 cells/L) had inferior progression free survival (PFS) (median PFS: 17.2 m vs. 43.7 m, P = 0.019) and overall survival (OS) (median OS: 29.0 m vs 39.1 m, P = 0.012). Multivariate Cox analysis revealed that age, smoking history, clinical stage, and ALC nadir were independent OS (P = 0.006, P = 0.005, P < 0.001 and P = 0.027, respectively), as well as independent PFS predictors (P = 0.032, P = 0.012, P = 0.012 and P = 0.018, respectively). After internal cross-validation, the corrected concordance indices of the predictive nomograms for PFS and OS were 0.637 and 0.663, respectively. Conclusion: LS-SCLC patients with a low ALC nadir during PCI likely have worse survival outcomes. Dynamic evaluation of the ALC during PCI is recommended for LS-SCLC patients.

Retrospective Clinical Study on Integrated Chinese and Western Medicine in Treatment of Limited-Stage Small Cell Lung Cancer.

OBJECTIVE: To investigate the efficacy of integrated Chinese and Western medicine extending the progression-free survival (PFS) and overall survival (OS) of limited-stage small cell lung cancer (LS-SCLC) patients after the first-line chemoradiotherapy. METHODS: The data of 67 LS-SCLC patients who received combined treatment of CM and Western medicine (WM) between January 2013 and May 2020 at the outpatient clinic of Guang'anmen Hospital were retrospectively analyzed. Thirty-six LS-SCLC patients who received only WM treatment was used as the WM control group. The medical data of the two groups were statistically analyzed. Survival analysis was performed using the product-limit method (Kaplan-Meier analysis). The median OS and PFS were calculated, and survival curves were compared by the Log rank test. The cumulative survival rates at 1, 2, and 5 years were estimated by the life table analysis. Stratified survival analysis was performed between patients with different CM administration time. RESULTS: The median PFS in the CM and WM combination treatment group and the WM group were 19 months (95% CI: 12.357-25.643) vs. 9 months (95% CI: 5.957-12.043), HR=0.43 (95% CI: 0.27-0.69, P<0.001), respectively. The median OS in the CM and WM combination group and the WM group were 34 months (95% CI could not be calculated) vs. 18.63 months (95% CI: 16.425-20.835), HR=0.40 (95% CI: 0.24-0.66, P<0.001), respectively. Similar results were obtained in the further stratified analysis of whether the duration of CM administration exceeded 18 and 24 months (P<0.001). CONCLUSION: The combination treatment of CM and WM with continuing oral administration of CM treatment after the first-line chemoradiotherapy for LS-SCLC patients produced better prognosis, lower risks of progression, and longer survival than the WM treatment alone. (Registration No. ChiCTR2200056616).

Anti-programmed death ligand 1 immunotherapy in patients with limited-stage small cell lung cancer: a real-world exploratory study.

The aim of this study was to investigate the safety and efficacy of anti-programmed death ligand 1 (PD-L1) immunotherapy plus chemoradiotherapy for patients with limited-stage small cell lung cancer (LS-SCLC) in clinical practice. Patients with LS-SCLC treated with anti-PD-L1 (atezolizumab/durvalumab) plus chemoradiotherapy (CRT) as the initial treatment at three general hospitals between March 2020 and December 2021 were retrospectively analysed. 1:2 propensity score matching for controls that receive CRT only was performed. Clinical data (age, sex, history of cancer treatment, adverse events, etc.) were collected to evaluate toxicity, progression-free survival (PFS) and objective response rate (ORR). Researchers used univariate Chi-squared analyses to determine if anti-PD-L1 immunotherapy had a significant association with toxicity or ORR. Kaplan-Meier survival analysis, and the log-rank test were used to compare survival curves between the two groups. In the anti-PD-L1 plus CRT and CRT groups, 15 and 30 patients were analyzed; median follow-up was 16.39 months and 16.64 months, respectively. Incidence of toxicity between the two groups was similar and there were no new safety signals. Anti-PD-L1 immunotherapy significantly improved PFS (P = 0.02). The median PFS was not reached in the anti-PD-L1 plus CRT group versus 8.18 months [95% confidence interval (CI), 6.14-10.22 months] in the CRT group. The ORR were 93.33% and 76.67%, respectively (P = 0.34). This study supports adding anti-PD-L1 immunotherapy (atezolizumab/durvalumab) to CRT as an initial treatment option in patients with LS-SCLC for its favorable safety profile and efficacy.

Clinical Efficiency and Safety of Hypofractionated Thoracic Radiotherapy Combined with EP Chemotherapy on Patients with Limited-stage Small-cell Lung Cancer / 肿瘤防治研究

Objective To investigate the efficacy and safety of hypofractionated thoracic radiotherapy combined with EP chemotherapy in the treatment of limited-stage small-cell lung cancer (LS-SCLC). Methods A total of 117 patients with LS-SCLC were enrolled and randomly divided into test group (n=59) and control group (n=58). Patients in the experiment group were given hypofractionated thoracic radiotherapy combined with EP chemotherapy, while patients in the control group were given hyperfractionation radiotherapy combined with EP chemotherapy. Objective response rate (ORR), 2-year overall survival (OS), 2-year progression free survival (PFS), and immune cell level were used to evaluate clinical efficacy. We compared the incidence of side effects between the two groups. Results After the treatment, the ORR of patients in the test group was higher than that in the control group (P > 0.05). The mean OS and PFS of patients in the test group were significantly longer than those in the control group (P < 0.05). The levels of CD3+, CD4+, CD4+/CD8+, and NK cells in the test group were significantly higher, whereas the levels of CD8+ were significantly lower than those in the control group (P < 0.05). The incidence of radiation pneumonitis, radiation esophagitis, and severe dermatitis in the test group was significantly lower than that in the control group (P < 0.05). Conclusion Hypofractionated radiotherapy combined with EP chemotherapy for treatment of LS-SCLC can effectively improve the anticancer efficacy and patient survival, reduce the damage to the body's immune function, and alleviate adverse reaction of radiotherapy.

Impact of the depth of remission by induction chemotherapy on the prognosis of limited stage small cell lung cancer / 中华肿瘤杂志

Objective: To evaluate the effect of depth of remission of induction chemotherapy on the overall prognosis of limited stage small cell lung cancer (L-SCLC). Methods: The study was a retrospective, L-SCLC patients who contained complete imaging data and underwent consecutive standardized treatments at the Department of Thoracic Radiation and Medical Oncology, Zhongnan Hospital of Wuhan University between January 2013 and June 2021 were included. To delineate the volume of tumor before and after induction chemotherapy and to calculate the depth of remission caused by the induced chemotherapy. The time receiver operating characteristic (timeROC) method was used to determine the optimal predictors for prognosis, multi-factor analysis using Cox risk proportional model. Results: A total of 104 patients were included in this study. The median PFS and OS of this cohort were 13.7 months and 20.9 months, respectively. It was observed by timeROC analysis that residual tumor volume after induction chemotherapy had the optimal predictive value of PFS at 1 year (AUC=0.86, 95% CI: 0.78~0.94) and OS at 2 years (AUC=0.76, 95% CI: 0.65~0.87). Multivariate analysis showed residual tumor volume after induction chemotherapy was the independent prognostic factor to PFS (HR=1.006, 95% CI: 1.003~1.009, P<0.01) and OS (HR=1.009, 95% CI: 1.005~1.012, P<0.001). For those whose residual tumor volume remitted to less than 10 cm(3) after induction chemotherapy, the favorable long-term outcomes could be achieved, regardless of their initial tumor load. Conclusion: The depth of remission of induction chemotherapy could be a promising prognostic predictor to the L-SCLC and provide the individualized treatment guidance.

Retrospective Clinical Study on Integrated Chinese and Western Medicine in Treatment of Limited-Stage Small Cell Lung Cancer / 中国结合医学杂志

OBJECTIVE@#To investigate the efficacy of integrated Chinese and Western medicine extending the progression-free survival (PFS) and overall survival (OS) of limited-stage small cell lung cancer (LS-SCLC) patients after the first-line chemoradiotherapy.@*METHODS@#The data of 67 LS-SCLC patients who received combined treatment of CM and Western medicine (WM) between January 2013 and May 2020 at the outpatient clinic of Guang'anmen Hospital were retrospectively analyzed. Thirty-six LS-SCLC patients who received only WM treatment was used as the WM control group. The medical data of the two groups were statistically analyzed. Survival analysis was performed using the product-limit method (Kaplan-Meier analysis). The median OS and PFS were calculated, and survival curves were compared by the Log rank test. The cumulative survival rates at 1, 2, and 5 years were estimated by the life table analysis. Stratified survival analysis was performed between patients with different CM administration time.@*RESULTS@#The median PFS in the CM and WM combination treatment group and the WM group were 19 months (95% CI: 12.357-25.643) vs. 9 months (95% CI: 5.957-12.043), HR=0.43 (95% CI: 0.27-0.69, P<0.001), respectively. The median OS in the CM and WM combination group and the WM group were 34 months (95% CI could not be calculated) vs. 18.63 months (95% CI: 16.425-20.835), HR=0.40 (95% CI: 0.24-0.66, P<0.001), respectively. Similar results were obtained in the further stratified analysis of whether the duration of CM administration exceeded 18 and 24 months (P<0.001).@*CONCLUSION@#The combination treatment of CM and WM with continuing oral administration of CM treatment after the first-line chemoradiotherapy for LS-SCLC patients produced better prognosis, lower risks of progression, and longer survival than the WM treatment alone. (Registration No. ChiCTR2200056616).

Prognostic ability of lung immune prognostic index in limited-stage small cell lung cancer.

BACKGROUND: Lung immune prognostic index (LIPI) is a prognostic marker of extensive-stage small cell lung cancer (ES-SCLC) patients received immunotherapy or chemotherapy. However, its ability in limited-stage SCLC (LS-SCLC) should be evaluated extensively. METHODS: We retrospectively enrolled 497 patients diagnosed as LS-SCLC between 2015 and 2018, and clinical data included pretreatment lactate dehydrogenase (LDH), white blood cell count, and absolute neutrophil count levels were collected. According to the LIPI scores, the patients were stratified into low-risk (0 points) and high-risk (1-2 points). The correlations between LIPI and overall survival (OS) or progression-free survival (PFS) were analyzed by the Cox regression. Additionally, the propensity score matching (PSM) and inverse probability of treatment weight (IPTW) methods were used to reduce the selection and confounding bias. A nomogram was constructed using on multivariable Cox model. RESULTS: Two hundred fifty and 247 patients were in the LIPI high-risk group and low-risk group, and their median OS was 14.67 months (95% CI: 12.30-16.85) and 20.53 months (95% CI: 17.67-23.39), respectively. In the statistical analysis, High-risk LIPI was significantly against worse OS (HR = 1.377, 95%CI:1.114-1.702) and poor PFS (HR = 1.338, 95%CI:1.1-1.626), and the result was similar after matching and compensating with the PSM or IPTW method. A novel nomogram based on LIPI has a decent level of predictive power. CONCLUSION: LIPI stratification was a significant factor against OS or PFS of LS-SCLC patients.

Prophylactic cranial irradiation (PCI) versus active surveillance in patients with limited-stage small cell lung cancer: a retrospective, multicentre study.

BACKGROUND: The recommendation of PCI for limited-stage small cell lung cancer (LS-SCLC) is primarily based on evidence from the pre-magnetic resonance imaging (MRI) era. However, as MRI accuracy improves and stereotactic radiosurgery advances, the role of PCI for LS-SCLC has become uncertain. This study aims to compare the contemporary survival outcomes of patients with LS-SCLC treated with PCI versus active surveillance. METHODS: We conducted a retrospective cohort study in which 1068 patients with LS-SCLC who achieved a good response to first-line chemoradiotherapy were consecutively enrolled from 5 tertiary medical centres between June 2009 and June 2019. Of these patients, 440 received PCI, while 628 received surveillance without PCI. Propensity score matching with a 1:1 ratio was performed to balance the baseline characteristics of the two cohorts. The endpoints were overall survival (OS) and the incidence of brain metastasis (BM). RESULTS: In total, 648 patients were matched. The baseline characteristics were generally well balanced. At a median follow-up of 64.5 months (range 2-190), patients who underwent PCI had a significantly lower risk for BM than those who underwent surveillance. The 3-year cumulative incidence rate of BM was 28.2% (95% CI 22.5-33.8%) in the PCI cohort and 38.5% (32.6-44.5%) in the surveillance cohort (Gray's p = 0.002). However, the lower incidence of BM in the PCI cohort did not translate into a significant extension of OS. The median OS was 35.8 months (95% CI 27.6-44.0 months) in the PCI cohort versus 32 months (26.4-37.6 months) in the surveillance cohort (HR 0.90, 95% CI 0.74-1.10, p = 0.29). Multivariable analysis showed that disease stage, chemoradiotherapy sequence, and response to chemoradiotherapy were independent prognostic factors for BM or OS. CONCLUSIONS: Overall, PCI reduces the risk for BM but does not substantially prolong OS compared with active surveillance. A phase 3, prospective clinical trial (NCT04829708) we initiated is currently underway, which is expected to corroborate our results.

Pathologic responses to neoadjuvant chemoimmunotherapy in primary limited-stage small-cell lung cancer.

BACKGROUND: Immunotherapy has been proved to have a large effect on extensive-stage small cell lung cancer, but the role of immunotherapy in limited-stage small-cell lung cancer (LS-SCLC) is still unknown. METHODS: A retrospective study of six patients with LS-SCLC who were treated with neoadjuvant chemoimmunotherapy (durvalumab plus etoposide combined with cisplatin) was performed. Patients were evaluated by the safety, feasibility and pathologic responses of neoadjuvant chemoimmunotherapy. RESULTS: Neoadjuvant durvalumab combined chemotherapy was associated with few immediate adverse events and did not delay planned surgery. All patients achieved partial pathologic response (pPR) instead of major pathologic response, or pathologic complete response. No association was observed between programmed death-ligand 1 expression in tumor specimens and the pathologic response. However, tumors with high expression of immune cells such as CD4+ T cells, CD8+ T cells and FoxP3+ Tregs tended to have better pathologic responses than tumors with low expression of immune cells. CONCLUSIONS: Neoadjuvant durvalumab combined chemotherapy could induce pPR with few side effects in resectable LS-SCLC. The immune cells in the tumor microenvironment might play an important role in neoadjuvant chemoimmunotherapy in resectable LS-SCLC.

Effectivity of involved-field radiotherapy for recurrent brain metastasis in patients with small-cell lung cancer.

Objectives: To investigate the outcome difference of whole brain radiotherapy (WBRT) and involved-field radiotherapy (IFRT) in limited-stage small-cell lung cancer (LS-SCLC) patients with recurrent brain metastases (BMs) after prophylactic cranial irradiation (PCI). Methods: A retrospective analysis was carried out in 68 LS-SCLC patients who underwent WBRT or IFRT owing to the occurrence of recurrent BMs after PCI from 2009 to 2020. Results: The median overall survival (OS) of all patients was 11.43 months [95% confidence interval (CI) 9.39-13.48 months]. In the paired comparison of OS, the IFRT group had a significantly longer survival time than the WBRT group in all patients [17.80 months vs. 8.47 months; hazard ratio (HR), 0.393, 95% CI, 0.213-0.728; P = 0.002] and 46 matched patients (18.23 months vs. 8.73 months; HR, 0.411, 95% CI, 0.195-0.865; P = 0.019). In terms of the intra-cranial progression-free survival (iPFS), there was no significant difference between the WBRT group and IFRT group before matching (5.93 months vs. 7.30 months; HR, 0.644, 95% CI, 0.373-1.112; P = 0.111); similarly, no statistical difference was detected between the WBRT group and IFRT group after matching (5.33 months vs. 8.10 months; HR, 0.623, 95% CI, 0.323-1.199; P = 0.152). Meanwhile, of the 41 patients with symptoms, 27 cases (65.9%) had symptom relief, showing tolerable toxicity without unexpected toxicity during the observation. Conclusions: Compared with WBRT, IFRT exhibits better survival benefits for LS-SCLC patients with recurrent BMs after PCI. Re-irradiation for BMs exhibits advantages of symptom relief and tolerable side effects.

Corrigendum: Progression-free survival and time to progression as potential surrogate endpoints for overall survival in chemoradiotherapy trials in limited-stage small-cell lung cancer: A systematic review and meta-analysis.

[This corrects the article DOI: 10.3389/fonc.2022.810580.].

Usefulness of pro-gastrin-releasing peptide as a predictor of the incidence of brain metastasis and effect of prophylactic cranial irradiation in patients with limited-stage small-cell lung cancer.

Prophylactic cranial irradiation (PCI) is recommended for patients with limited-stage small-cell lung cancer (LS-SCLC) who respond well to initial treatment. However, PCI is often omitted because of its potential neurotoxicity in the era of modern diagnostic imaging devices. In the present study, we aimed to investigate the risk factors for brain metastasis (BM) in patients eligible for PCI and who may benefit more from it. Patients with LS-SCLC who responded well to definitive thoracic chemoradiotherapy were included in the present study. Competing risk regression was used to identify factors associated with BM, and the Kaplan-Meier method was used to assess overall survival (OS). Between 2004 and 2017, 62 patients were eligible for PCI and were analyzed. Of these, 38 (61.3%) underwent PCI. Overall, 17 patients (27.4%) developed BM, with a 2-year cumulative incidence of 22.8%. Multivariate analysis (MVA) revealed that pretreatment elevated pro-gastrin-releasing peptide (ProGRP) levels were associated with an increased risk for BM (HR, 7.96, P = 0.0091). PCI tended to reduce the risk of BM (HR, 0.33; P = 0.051). The use of PCI was associated with improved OS in patients with ProGRP levels > 410 pg/mL (P = 0.008), but not in those with ProGRP ≤ 410 pg/mL (P = 0.9). Pretreatment ProGRP levels may be useful in predicting the development of BM in patients with LS-SCLC who achieved a good response to initial therapy and to determine which patients should undergo PCI.

Immune Checkpoint Inhibitors and Chemoradiation for Limited-Stage Small Cell Lung Cancer.

OPINION STATEMENT: Limited-stage small cell lung cancer (LS-SCLC) is a potentially curable disease. However, most patients develop disease relapse shortly after definitive treatment. The landmark trials IMpower133 and CASPIAN demonstrated a survival benefit with the addition of immunotherapy to first-line platinum/etoposide for extensive-stage small cell lung cancer. Therefore, it is critical to determine whether advancements in overall survival with immunotherapy can be translated earlier into the treatment paradigm for LS-SCLC. Decades of robust preclinical research into the synergism of radiation therapy and immunotherapy set the stage for the combination of these treatment modalities. Recently published data suggests tolerability of single agent immunotherapy concurrent with chemoradiation in LS-SCLC, along with promising efficacy. However, combination immunotherapy in the consolidation setting appears too toxic, although this may be reflective of the dosing schedule rather than inherent to any combination immune checkpoint blockade. Here, we review underlying mechanisms of synergy with the combination of radiation and immunotherapy, the safety and efficacy of respective treatment modalities, and the ongoing trials that are exploring novel therapeutic approaches for LS-SCLC. Pivotal trials in LS-SCLC are ongoing and anticipated to aid in understanding efficacy and safety of immunotherapy with concurrent platinum-based chemoradiotherapy.