A meta-analysis of thoracic radiotherapy for small-cell lung cancer

Effect of FDG PET-CT for Staging and Radiotherapy Planning - A Comparison of Cohorts From Two Randomized Trials of Thoracic Radiotherapy in Limited-Stage SCLC

Introduction

18F-fluorodeoxyglucose positron emission tomography-computed tomography (PET-CT) is recommended for staging and defining target volume in limited-stage SCLC, though the impact on outcomes compared with CT staging and elective nodal irradiation (ENI) is not well documented. We analyzed patients receiving 45 Gy/30 fractions in two randomized trials of thoracic radiotherapy (TRT) in limited-stage SCLC (HAST and THORA trials) to evaluate whether PET-CT for staging and radiotherapy planning reduces radiotoxicity and improves survival.

Methods

Patients in HAST were staged with CT of the thorax and upper abdomen and brain magnetic resonance imaging of the brain. Patients in THORA were staged with PET-CT in addition. All patients were to receive four courses of platinum/etoposide chemotherapy and concurrent TRT starting three to four weeks after the first chemotherapy course. In HAST, target volumes included pathological lesions on CT plus ENI of lymph node stations 4-7 (bilateral). In THORA, target volumes were limited to PET-CT-positive lesions (selective nodal irradiation [SNI]).

Results

A total of 149 patients were included (PET-CT/SNI: n = 76, CT/ENI: n=73); the median age was 64 years, 56% were women, 85% had PS 0 to 1, and 81% had stage III disease. The PET-CT/SNI group experienced less grade 3-4 esophagitis (18% versus 33%, p = 0.043), less grade >=1 pneumonitis (5% versus 16%, p = 0.028), and less dysphagia after TRT (mean scores on European Organisation for Research and Treatment of Cancer 13-item lung cancer module: 45 versus 72). There was no difference in median overall survival (24 versus 25 mo, p = 0.59) or progression-free survival (11 versus 11 mo, p = 0.23).

Conclusions

Using PET-CT for staging and target volume definition of TRT reduces acute radiotoxicity but does not improve overall or progression-free survival in limited-stage SCLC.

Small cell lung cancer: emerging subtypes, signaling pathways, and therapeutic vulnerabilities

Small cell lung cancer (SCLC) is a recalcitrant cancer characterized by early metastasis, rapid tumor growth and poor prognosis. In recent decades, the epidemiology, initiation and mutation characteristics of SCLC, as well as abnormal signaling pathways contributing to its progression, have been widely studied. Despite extensive investigation, fewer drugs have been approved for SCLC. Recent advancements in multi-omics studies have revealed diverse classifications of SCLC that are featured by distinct characteristics and therapeutic vulnerabilities. With the accumulation of SCLC samples, different subtypes of SCLC and specific treatments for these subtypes were further explored. The identification of different molecular subtypes has opened up novel avenues for the treatment of SCLC; however, the inconsistent and uncertain classification of SCLC has hindered the translation from basic research to clinical applications. Therefore, a comprehensives review is essential to conclude these emerging subtypes and related drugs targeting specific therapeutic vulnerabilities within abnormal signaling pathways. In this current review, we summarized the epidemiology, risk factors, mutation characteristics of and classification, related molecular pathways and treatments for SCLC. We hope that this review will facilitate the translation of molecular subtyping of SCLC from theory to clinical application.

A retrospective study on the impact of radiotherapy on the survival outcomes of small cell lung cancer patients based on the SEER database

Small cell lung cancer (SCLC) patients exhibit significant heterogeneity in tumor burden, physical condition, and responses to initial treatment. This diversity in treatment responses can result in varying treatment outcomes. The primary objective of this study was to explore the patient demographics associated with improved survival outcomes through radiotherapy. Based on the SEER database, we identified 42,824 SCLC patients enrolled between 2004 and 2015. These patients were stratified into radiotherapy (n = 20,360) and non-radiotherapy groups (n = 22,464). We controlled for confounding factors using propensity score matching (PSM) analysis. Subsequently, Kaplan-Meier (KM) analysis was employed to evaluate the impact of radiotherapy on patients' overall survival (OS) and cancer-specific survival (CSS). Cancer-specific mortality was further analyzed using competitive risk models. Cox analysis was also conducted to examine additional variables potentially affecting the survival of SCLC patients. We identified a total of 42,824 eligible patients, and following PSM, 13,329 patients were successfully matched in both the radiotherapy and non-radiotherapy groups. The KM analysis showed that the median OS was 9 months in the radiotherapy group and 6 months in the non-radiotherapy group. The median CSS was 10 months in the radiotherapy group and 7 months in the non-radiotherapy group. The 5-year OS and 10-year OS rates were 6.2% versus 1.6% in the radiotherapy group and 2.6% versus 0.8% in the non-radiotherapy group (P < 0.001). Competitive risk analysis showed that cancer-specific mortality was significantly higher in the non-radiotherapy group than in the radiotherapy group (P < 0.001). Multivariate Cox analysis showed that the radiotherapy group (relative non-radiotherapy group) showed a significant positive effect on survival outcomes (OS: HR 0.658 95% CI [0.642, 0.675] P < 0.001; CSS: HR 0.662 95% CI [0.645, 0.679], P < 0.001). In addition, age, gender, race, primary tumor site, T stage, N stage, M stage, chemotherapy, and surgery were also considered as important predictors of SCLC outcome. The results of the subgroup analysis showed that the radiotherapy group showed a significant survival advantage regardless of age, sex, race, primary tumor site, M stage, chemotherapy, and surgery (P < 0.001). Radiotherapy may improve both OS and CSS in SCLC patients. Patients with SCLC may benefit from radiotherapy regardless of age, sex, race, primary tumor site, M stage, chemotherapy, and surgery.

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.

Effect of Matrix Stiffness and Hepatocyte Growth Factor on Small Cell Lung Cancer Cells in Decellularized Extracellular Matrix-Based Hydrogels

Small cell lung cancer (SCLC) is one of lethal cancers resulting in very low 5-year-survival rate. Although its clinical treatment largely relies on chemotherapy, SCLC cell physiology in three-dimenstional (3D) matrix has been less explored. In this work, the tumor microenvironment is reconstructed with decellularized porcine pulmonary extracellular matrix (dECM) with hyaluronic acid. To modulate matrix stiffness, the methacrylate groups are introduced into both dECM and hyaluronic acid, followed by photocrosslinking with photoinitiator. The stiffness of the resulting dECM-based hydrogel covers the stiffness of normal or cancerous tissue with varying dECM content. The proliferation and cancer stem cell marker expression of encapsulated SCLC cells are promoted in a compliant hydrogel matrix, which has a low shear modulus similar to that of the normal tissue. The hepatocyte growth factor (HGF) that induces SCLC cell invasion and chemoresistance markedly increases invasiveness and gene expression levels of CD44 and Sox2 in the hydrogel matrix. In addition, HGF treatment causes higher resistance against anticancer drugs (cisplatin and paclitaxel) in the 3D microenvironment. These findings indicate that malignant SCLC can be recapitulated in a pulmonary dECM-based matrix.

Radiotherapy in the management of synchronous metastatic lung cancer

Metastatic lung cancer classically portends a poor prognosis. The management of metastatic lung cancer has dramatically changed with the emergence of immune checkpoint inhibitors, targeted therapy and due to a better understanding of the oligometastatic process. In metastatic lung cancers, radiation therapy which was only used with palliative intent for decades, represents today a promising way to treat primary and oligometastatic sites with a curative intent. Herein we present through a literature review the role of radiotherapy in the management of synchronous metastatic lung cancers.

Potential role of pre-treatment bone marrow SUVmean to liver SUVmean ratio (BM/L) and comparison of primary tumour FDG uptake with brain FDG uptake in predicting survival in limited-stage lung cancers

INTRODUCTION

The survival rates of patients with limited-stage small-cell lung cancer are low despite curative treatment. Accordingly, we investigated the disease prognosis by comparing the pre-treatment bone marrow mean standardised uptake values (SUVmean) / liver SUVmean ratio (BM/L) and primary tumour FDG uptake and brain FDG uptake to prognosis.

MATERIALS AND METHODS

This was an observational, retrospective, single-centre study of patients with limited-stage small-cell lung cancer. Maximum standardised uptake values before treatment SUVmax, mean SUV (SUVmean), metabolic tumor volume (MTV), total lesion glycolysis (TLG), liver (KC) SUVmean, bone marrow SUVmean, BM/L ratio (grouped as BM/L <1 and BM/L<1), FDG uptake level of the primary tumour are higher than brain FDG uptake. The association of low prevalence with overall survival (OS) and progression-free survival (PFS) was evaluated.

DISCUSSION

A total of 125 patients were included in the study. The risk of death was found to be two times higher in patients with primary tumour FDG uptake higher than brain FDG uptake compared to those with less brain involvement. The risk of death in patients with BM/L>1 was found to be 1.6 times higher than in patients with BM/L<1.

CONCLUSION

Comparison of BM/L, FDG uptake of the primary tumour and brain FDG uptake as new prognostic parameters can be guiding in the classification of patients with LD-SCLC with a higher risk of death or progression and in planning new treatment strategies.

Pulmonary function and toxicities of proton versus photon for limited-stage small cell lung cancer

PURPOSE

We aimed to compare the oncological outcomes and toxicities of definitive proton beam therapy (PBT) and photon beam therapy in patients with limited-stage small cell lung cancer (LS-SCLC).

MATERIALS AND METHODS

We retrospectively reviewed 262 patients with newly diagnosed LS-SCLC who underwent definitive PBT (n = 20; proton group) or photon beam therapy (n = 242; photon group) with concurrent chemotherapy between January 2016 and February 2021 and compared overall survival (OS), progression-free survival (PFS), dose-volume parameters, and toxicities between the groups.

RESULTS

The median follow-up duration was 24.5 months (range, 3.7 to 78.7). Baseline lung function was significantly worse and clinical target volume (CTV) was larger in the proton group (CTV: 296.6 vs. 215.3 mL; p = 0.080). The mean lung V10 was 37.7% ± 16.8% and 51.6% ± 24.5% in the proton and photon groups, respectively (p = 0.002). Two-year OS and PFS rates were 57.2% and 35.7% in the proton group and 65.3% and 40.8% in the photon group, respectively (p = 0.542 and 0.748, respectively). Grade ≥2 radiation pneumonitis and esophagitis occurred in 5 (25.0%) and 7 (35.0%) PBT-treated patients and 66 (27.3%) and 40 (16.5%) photon beam therapy-treated patients, respectively (p = 0.826 and 0.062, respectively).

CONCLUSION

Although the proton group had poorer lung function and a larger CTV than that in the photon group, both groups exhibited comparable treatment outcomes and radiation-related toxicities in LS-SCLC. PBT may be a valuable therapeutic modality in patients with poor pulmonary function or extensive disease burden owing to its lung-sparing ability.

Survival outcomes and prognostic nutritional index in very elderly small-cell lung cancer patients: importance of active treatment and nutritional support

BACKGROUND

Small-cell lung cancer (SCLC) is a highly aggressive tumor with a high metastatic potential, particularly affecting current or former heavy smokers. Treatment typically involves chemotherapy, often combined with radiotherapy, and immunotherapy for extensive disease. Prophylactic cranial irradiation is recommended to reduce brain metastases. Elderly SCLC patients face unique challenges due to frailty and comorbidities, leading to increased risks of treatment-related toxicity and malnutrition. The prognostic nutritional index (PNI), a composite marker of nutritional and immune status, has shown promise in predicting outcomes in various malignancies. However, the optimal treatment approach for very elderly SCLC patients remains unclear, as they are often excluded from clinical trials.

AIMS

This study aimed to evaluate the survival outcomes of SCLC patients aged 75 years or older and their correlation with PNI.

STUDY DESIGN

Retrospective cohort study.

METHODS

The study retrospectively analyzed data from 71 SCLC patients aged ≥75 years, focusing on age, gender, smoking status, chronic diseases, performance status, clinical stage, treatment modality, and pretreatment PNI. Survival estimates were calculated using the Kaplan-Meier method, and multivariate Cox regression analysis was performed to identify independent predictors of overall survival (OS).

RESULTS

The results demonstrated that 26.8% of very elderly SCLC patients received no active treatment, resulting in a significantly shorter median survival time of 1.3 months. In contrast, patients who underwent aggressive treatment, such as palliative chemotherapy or chemotherapy plus radiotherapy, had significantly longer median survival times. Multivariate analysis revealed that receiving chemotherapy plus radiotherapy was associated with a significant survival benefit compared to no treatment. Furthermore, low PNI (≤40) was independently associated with decreased OS.

CONCLUSION

This study highlights the importance of active treatment and nutritional support in improving survival outcomes for very elderly SCLC patients. The findings suggest that low PNI and lack of oncological treatment are associated with worse survival outcomes. Therefore, integrating nutritional assessment, interventions, and appropriate treatment strategies are crucial in managing lung cancer patients. Larger, multicenter studies are needed to validate these findings and explore potential interventions to optimize nutritional status and improve outcomes for elderly patients with SCLC.

Role of radiotherapy in the management of rare gynaecological cancers

There are a large number of gynaecological cancers with rare histologies, for which the available data are limited and usually retrospective. Because of their rarity and poor prognosis, the management of these cancers must be centralized in expert centres, for both histological diagnosis and treatment. With the exception of sarcomas, most endometrial or cervical cancers with rare histologies respond to the same radiation treatment modalities than cancers with more common histologies, although there are some specificities regarding treatments such as neuroendocrine carcinomas (chemotherapy with platinum and etoposide, major role of surgery). For localized or locally advanced ovarian cancer, external beam radiotherapy has a role in the management of hypercalcaemic small cell carcinoma of the ovary. This article summarizes the current role of external beam radiotherapy and brachytherapy in the management of cancers of the uterine cervix, uterine corpus and ovaries, with rare or very rare histologies, and with localized or locally advanced stages.

Advancing immunotherapy in small cell lung cancer

Small cell lung cancer (SCLC) is a rapidly progressive neuroendocrine carcinoma that, until recently, had a very small armamentarium of effective treatments. Advances in DNA sequencing and whole transcriptomics have delineated key subtypes; therefore, SCLC is no longer viewed as a homogeneous cancer. Chemoimmunotherapy with PD1 blockade is now the standard of care for advanced disease, and ongoing research efforts are moving this strategy into the limited stage setting. Combination strategies of immunotherapy with radiation are also under active clinical trial in both limited and extensive stage disease. PLAIN LANGUAGE SUMMARY: Small cell lung cancer (SCLC) is a rapidly progressive neuroendocrine carcinoma that, until recently, had a very small armamentarium of effective treatments. Chemoimmunotherapy with immune check point inhibitors is now the standard of care for advanced disease. This comprehensive review provides an overview of current treatment strategies for SCLC, unmet needs in this patient population, and emerging treatment strategies incorporating immunotherapy that will hopefully further improve outcomes for patients.

Real-world utilization of immune checkpoint inhibitors in extensive stage small-cell lung cancer in community settings

Aim: This study examined real-world treatment patterns for extensive-stage small-cell lung cancer (ES-SCLC) after immune checkpoint inhibitors (ICIs) became available for frontline use. Methods: Adult patients with ES-SCLC initiating 1L systemic treatment were identified from electronic health records. Results: Among patients with recurrent/progressive ES-SCLC, the most common treatment classes were platinum-based chemotherapy (81.1% of 228) and ICI monotherapy (35.1% of 191) in 1L and 2L, respectively. Among patients with de novo ES-SCLC, the most common treatment classes were ICI + platinum-based chemotherapy (64.4% of 1268) and other chemotherapy (44.9% of 512) in 1L and 2L, respectively. Among patients who received no ICI in 1L, 62.6%-70.3% received it in 2L and 62.6-68.5% in 3L. Some who received 1L ICI were re-treated with ICI in subsequent lines (14.5-18.8% in 2L, 18.2-50.0% in 3L). Conclusion: Real-world ICI utilization in ES-SCLC, particularly ICI re-challenge, demonstrates high unmet needs in this patient population.

Reduction of tumor volume during radiotherapy in patients with small-cell lung cancer and its prognostic significance

BACKGROUND

Several studies have reported the potential prognostic significance of tumor volume reduction ratio (VRR) induced by radiotherapy (RT) in patients with non-small-cell lung cancer. However, there are no data yet on the prognostic significance of volumetric shrinkage in patients with small-cell lung cancer (SCLC). This study aimed to demonstrate the correlation between tumor volume reduction ratio and treatment outcomes.

MATERIALS AND METHODS

The study included 61 patients with SCLC treated with fractionated RT of the primary tumor at our institution between 2013 and 2020. The relationship between volumetric changes in gross tumor volume (GTV) during radiotherapy and outcomes were analyzed and reported.

RESULTS

The median radiation dose was 59.4 Gy (median fraction dose was 1.8 Gy). The median GTV before radiotherapy was 74 cm3, with a median GTV reduction of 48%. There was a higher VRR in patients receiving concurrent radiochemotherapy (p = 0.05). No volumetric parameters were identified as relevant predictors of outcome in the entire cohort. In multivariate analysis, only age had an impact on survival, while prophylactic whole-brain radiation influenced the progression-free survival significantly.

CONCLUSION

Concurrent chemotherapy was associated with a higher VRR than sequential chemotherapy. No significant impact of VRR on patients' outcome or survival was detected.

[Prevention, Diagnosis, Therapy, and Follow-up of Lung Cancer - Interdisciplinary Guideline of the German Respiratory Society and the German Cancer Society - Abridged Version]

The current S3 Lung Cancer Guidelines are edited with fundamental changes to the previous edition based on the dynamic influx of information to this field:The recommendations include de novo a mandatory case presentation for all patients with lung cancer in a multidisciplinary tumor board before initiation of treatment, furthermore CT-Screening for asymptomatic patients at risk (after federal approval), recommendations for incidental lung nodule management , molecular testing of all NSCLC independent of subtypes, EGFR-mutations in resectable early stage lung cancer in relapsed or recurrent disease, adjuvant TKI-therapy in the presence of common EGFR-mutations, adjuvant consolidation treatment with checkpoint inhibitors in resected lung cancer with PD-L1 ≥ 50%, obligatory evaluation of PD-L1-status, consolidation treatment with checkpoint inhibition after radiochemotherapy in patients with PD-L1-pos. tumor, adjuvant consolidation treatment with checkpoint inhibition in patients withPD-L1 ≥ 50% stage IIIA and treatment options in PD-L1 ≥ 50% tumors independent of PD-L1status and targeted therapy and treatment option immune chemotherapy in first line SCLC patients.Based on the current dynamic status of information in this field and the turnaround time required to implement new options, a transformation to a "living guideline" was proposed.

Investigation of the efficacy and feasibility of combined therapy of PD-L1-enhanced exogenous peripatetic adoptive natural killer (NK) cells in combination with antiangiogenic targeted therapy in the treatment of extensive-stage small cell lung cancer

A 67-year-old male patient presented with extensive-stage small cell lung cancer with the primary lesion located in the right upper lung, accompanied by multiple metastases to the pleura and abdominal cavity with enlarged mediastinal lymph nodes. A combination therapy approach was used to target the patient's multiple systemic metastases after localized radiotherapy. The approach involved adoptive transfer of programmed death ligand 1 (PD-L1) enhanced exogenous natural killer (NK) cells, along with antiangiogenic treatment. Allogeneic cord blood NK cells were infused back into the patient over two consecutive days. On the first day, the treatment was followed by a dose of 1200 mg of atezolizumab. Subsequently, the patient received a daily dose of 10 mg of anlotinib administered orally for 14 days. This was followed by a 7-day break, and each cycle lasted 21 days. After delivering localized radiation to the primary lesion in the right lung and metastatic mediastinal lymph nodes, complete remission was achieved in the local lesion, effectively avoiding the risk of superior vena cava syndrome. Following six cycles of combined therapy, most of the metastatic lesions had disappeared, and the remaining metastatic lesions had significantly reduced in size. The recent therapeutic effect resulted in partial remission. The combination therapy of immune checkpoint inhibitor PD-L1-enhanced exogenous adoptive transfer NK cells, along with antiangiogenic targeted treatment, demonstrated a satisfactory short-term effect, with disappearance of most of the metastases and noticeable shrinkage in the remaining metastatic lesions.

Current Evidence and Future Perspectives about the Role of PARP Inhibitors in the Treatment of Thoracic Cancers

In recent years, poly (ADP-ribose) polymerase (PARP) inhibition has become a promising therapeutic option for several tumors, especially for those harboring a BRCA 1-2 mutation or a deficit in the homologous recombination repair (HRR) pathway. Nevertheless, to date, PARP inhibitors are still not largely used for thoracic malignancies neither as a single agent nor in combination with other treatments. Recently, a deeper understanding of HRR mechanisms, alongside the development of new targeted and immunotherapy agents, particularly against HRR-deficient tumors, traced the path to new treatment strategies for many tumor types including lung cancer and malignant pleural mesothelioma. The aim of this review is to sum up the current knowledge about cancer-DNA damage response pathways inhibition and to update the status of recent clinical trials investigating the use of PARP inhibitors, either as monotherapy or in combination with other agents for the treatment of thoracic malignancies. We will also briefly discuss available evidence on Poly(ADP-Ribose) Glycohydrolase (PARG) inhibitors, a novel promising therapeutic option in oncology.

Small-Cell Lung Cancer-An Update on Targeted and Immunotherapies

Small-cell lung cancer (SCLC) is an aggressive disease with distinct biological and clinical features. The clinical course of SCLC is generally characterised by initial sensitivity to DNA-damaging therapies, followed by early relapse and broad cross resistance to second line agents. Whilst there has been an enormous expansion of effective targeted and immune-based therapeutic options for non-small cell lung cancer (NSCLC) in the last decade, little improvement has been achieved in SCLC treatment and survival due, at least in part, to underappreciated inter- and intra-tumoral heterogeneity. Here we review the current treatment paradigm of SCLC including recent advances made in utilizing immunotherapy and the challenges of identifying a predictive biomarker for immunotherapy response. We examine emerging new targeted therapies, combination immunotherapy and future directions of SCLC treatment research.

Waiting for Big Changes in Limited-Stage Small-Cell Lung Cancer: For Now, More of the Same

The Oncology Grand Rounds series is designed to place original reports published in the Journal into clinical context. A case presentation is followed by a description of diagnostic and management challenges, a review of the relevant literature, and a summary of the authors' suggested management approaches. The goal of this series is to help readers better understand how to apply the results of key studies, including those published in Journal of Clinical Oncology, to patients seen in their own clinical practice.Concurrent chemoradiotherapy remains central to the treatment of limited-stage small-cell lung cancer (SCLC). SCLC is one of the few tumors treated with twice-daily radiotherapy (RT) in the primary definitive setting, a regimen that was established when Intergroup 0096 demonstrated its superiority over once-daily RT. However, questions remained about the optimal chemoradiotherapy regimen given the low RT dose used in the once-daily RT arm of Intergroup 0096. CALGB 30610/RTOG 0538 and CONVERT attempted to establish whether dose-escalated once-daily RT was superior to twice-daily RT in limited-stage SCLC. Although both studies showed similar survival between treatment regimens, once-daily RT was not found to be superior to twice-daily RT, and trial design limited the ability to conclude dose-escalated once-daily RT as noninferior to twice-daily RT. Thus, twice-daily RT with concurrent chemotherapy remains a standard of care in limited-stage SCLC.

Combining radiation therapy with immune checkpoint blockade for the treatment of small cell lung cancer

The addition of immune checkpoint blockade (ICB) therapy to standard chemotherapy has been shown to improve survival in patients with metastatic small cell lung cancer. However, the benefit is modest and there remains an unmet need for novel therapeutic approaches to enhance the effectiveness of immunotherapy in this disease, both in the early and late stages. Ionizing radiation, which is a standard treatment for small cell lung cancer, is known to trigger immunogenic cell death in tumor cells, making it an attractive partner for ICB therapies in multiple solid tumor types. However, the optimal radiation dosage and fractionation scheme, target sites for radiation, and sequencing of radiation in relation to ICB treatment are still unclear. In this review we discuss the molecular biology underlying radiation-induced tumor immunity as well as pre-clinical and clinical studies combining radiation with ICB treatments, with a focus on translational and clinical trials in small cell lung cancer.

Rare thoracic cancers: a comprehensive overview of diagnosis and management of small cell lung cancer, malignant pleural mesothelioma and thymic epithelial tumours

Despite the progress in outcomes seen with immunotherapy in various malignancies, including nonsmall cell lung cancer, the benefits are less in small cell lung cancer, malignant pleural mesothelioma and thymic epithelial tumours. New effective treatment options are needed, guided via more in-depth insights into the pathophysiology of these rare malignancies. This review comprehensively presents an overview of the clinical presentation, diagnostic tools, staging systems, pathophysiology and treatment options for these rare thoracic cancers. In addition, opportunities for further improvement of therapies are discussed.

Thoracic Radiation in Limited Stage Small Cell Lung Cancer: Trends in Radiation Fractionation

INTRODUCTION

Thoracic radiotherapy (TRT) is standard of care for limited-stage small cell lung cancer (LS-SCLC). Although initial data supported the use of twice-daily (BID) radiation to a dose of 45 Gy, recent trials have suggested similar efficacy with daily fractionation (QD) to a dose of 60 to 70 Gy. This study evaluates trends in treatment regimen in patients treated with TRT for LS-SCLC.

MATERIALS AND METHODS

The National Cancer Database (NCDB) was queried for patients with LS-SCLC treated with TRT between 2004 to 2017 grouped by RT fractionation QD vs. BID. Exclusion criteria were unknown stage, and unknown RT dose. Multivariable (MVA) analyses using logistic regression were performed to investigate factors associated with receipt of a specific fractionation schedule.

RESULTS

A total of 17,453 patients met inclusion criteria, with 4,996 receiving BID treatment and 12,457 receiving QD treatment. The most common QD dose was 60 Gy (48.9%). Overall, QD fractionation has increased (1.3%/year). In 2004, 45 Gy BID treatment (41.4%) was the dominant fractionation. By 2017, 60 Gy QD (45.2%) increased (1.9%/y) to be the dominant fractionation, while 45 Gy BID (24.8%) decreased (-1.4%/y) to be the second most common fractionation. On MVA, factors that affect 1 treatment over the other were further stratified.

CONCLUSION

Since 2004, QD fractionation has been the preferred TRT regimen for patients with LS-SCLC compared to BID fractionation, with the proportion of patients getting QD treatment continuing to increase. The choice of treatment regimen appears to be influenced by both patient and facility characteristics.

Radiotherapy Fraction in Limited-Stage Small Cell Lung Cancer in the Modern Era: A Systematic Review and Meta-Analysis of 8006 Reconstructed Individual Patient Data

The optimal thoracic radiotherapy (TRT) dose and fractionation for limited-stage small cell lung cancer (LS-SCLC) using modern techniques remain unclear. We conducted systematic review and meta-analyses of the efficacy and safety differences between definitive hypofractionated TRT (HypoTRT), conventional TRT (ConvTRT) and hyperfractionated TRT (HyperTRT), especially in the modern era. Eligible randomized controlled trials (RCTs), real-world cohorts, and single-arm trials published between 1990 and 2021 were identified. Two meta-analyses of overall survival (OS) were conducted: (i) a random-effects meta-analysis based on reconstructed individual-patient data (IPD) of all studies; and (ii) a Bayesian network meta-analysis based on study-level aggregated data (AD) of RCTs. The incidences of severe radiation-related toxicities were compared using the random-effects meta-regression model. Overall, 53 of the 30,031 publications met the inclusion criteria, and a total of 8006 IPD were reconstructed. After adjusting for key treatment variables and stratification by study type, there were no significant differences in the OS rates between the altered fractionation regimens (HypoTRT vs. HyperTRT, aHR [adjusted HR] = 1.05, 95% CI 0.93-1.19; ConvTRT vs. HyperTRT, aHR = 1.00, 95% CI 0·90-1.11; HypoTRT vs. ConvTRT, aHR = 1.05, 95% CI 0.91-1.20). In the modern era, the survival outcomes of all three schedules, while remaining comparable, have improved significantly. Results of the AD-based network meta-analysis were consistent with those of IPD analysis, and HypoTRT was ranked as the best regimen (SUCRA = 81%). There were no significant differences in toxicities between groups when using modern radiation techniques. In the modern era, no significant differences in OS or severe radiation-related toxicities were observed between altered schedules in LS-SCLC. HypoTRT may be associated with moderate and non-significant OS improvements, which should be further confirmed in prospective randomized phase III trials.

Lobectomy versus sublobar resection for stage I (T1-T2aN0M0) small cell lung cancer: A SEER population-based propensity score matching analysis

OBJECTIVE

This study evaluated whether sublobar resection (sub-L) is non-inferior to lobectomy (L) for stage I (T1-T2aN0M0) small cell lung cancer (SCLC) regarding long-term overall survival (OS).

METHODS

Clinicopathological and prognostic data of patients with stage I (pT1-T2aN0M0) SCLC were retrieved. Kaplan-Meier curves and Breslow tests were performed for the assessment of OS. Propensity score matching (PSM) analysis was used to mediate the inherent bias of retrospective researches.

RESULTS

A total of 188 patients with stage I SCLC were included in this study after PSM. For resected stage I SCLC, surgery plus adjuvant therapy was related to a better OS compared with surgery only (p = 0.016). For resected stage I SCLC, no matter adjuvant therapy was performed or not, no significant difference was observed in long-term OS between the L and sub-L groups (p = 0.181). Further subgroup analysis demonstrated that the OS disadvantage of sub-L over L was not statistically significant for stage I SCLC patients underwent surgery only (p = 0.653), but also for the patients underwent surgery plus adjuvant therapy (p = 0.069). Moreover, in the subgroup analyses according to TNM stage (IA and IB), sex (male and female), and age (≥70 and <70 years), OS did not differ between the L and sub-L groups except in female patients (p = 0.008). Multivariate Cox regression analysis indicated that adjuvant therapy was positively associated with OS.

CONCLUSIONS

Surgery plus adjuvant therapy confers a better survival benefit than surgery only for stage I SCLC patients. However, as far as the range of surgical resection is concerned, sublobar resection may be non-inferior to lobectomy regarding OS. Our study could conduce to the development of optimal therapeutic strategies for stage I SCLC patients. Further validation is warranted in larger retrospective and prospective cohort studies.

Incidence of Pneumonitis Among Limited Stage Small Cell Lung Cancer Patients Exposed to Concurrent Chemoradiation: A Systematic Literature Review and Meta-Analysis

Severe pneumonitis (≥ grade 3 by Common Terminology Criteria for Adverse Events [CTCAE]) is a toxicity associated with concurrent chemoradiation therapy (CCRT), which is the standard first-line treatment for patients with limited-stage small cell lung cancer (LS-SCLC). We summarize and quantify the risk of pneumonitis in LS-SCLC patients receiving first-line CCRT. A systematic literature review (SLR) and meta-analysis were performed in accordance with Cochrane and PRISMA guidelines. Electronic databases were searched to identify relevant randomized controlled trials (RCTs), observational studies, and non-randomized trials between 2014 to July 16, 2020. The primary outcome was incidence of pneumonitis. Thirteen studies were included in the SLR and 1539 pooled patients from 10 studies were included in the base-case meta-analysis. The pooled incidence of ≥ grade 3 pneumonitis was 3.28% (95% confidence interval [CI]: 1.52%-5.04%) in RCTs, and 6.34% (95% CI: 3.64%-9.04%) in non-RCTs. The pooled incidence risk of grade 5 (fatal) pneumonitis was 0.29% (95% CI: 0.00%-0.62%) in RCTs and 0.88% (95% CI: 0.02%-1.74%) in non-RCT. Results from sensitivity analyses were consistent with the base-case analysis. The results from this analysis show that the incidence of ≥ grade 3 pneumonitis in patients with LS-SCLC was 3.28% to 6.34%. The incidence of pneumonitis was higher in studies conducted in non-RCTs compared to RCTs. These results can be used to understand the safety, with regard to pneumonitis, of novel therapeutic agents when administered with CCRT to treat patients with LS-SCLC. To summarize and quantify the risk of pneumonitis in LS-SCLC patients receiving first-line CCRT, a systematic literature review (SLR) and meta-analysis were performed in accordance with Cochrane and PRISMA guidelines.

Recent advances in small cell lung cancer: the future is now?

Small cell lung cancer is a relevant clinical issue as it is a highly malignant cancer, often diagnosed in advanced stage. Similarly to non-small cell lung cancer, tobacco smoking is currently the main risk factor. Its incidence, at least in males, has declined over the past decades, due to the worldwide decreased percentage of active smokers. The typical small cells of this tumor type are characterized by a high Proliferation Index, chromosomal deletions such as 3p(14-23) involving the tumor-suppressor gene FHIT, alterations of the MYC or Notch family proteins and the frequent expression of neuroendocrine markers. The combination of thoracic radiotherapy and chemotherapy is the standard treatment for limited stage disease, while platinum-based chemotherapy is the most effective choice for extensive stage disease. Unfortunately, whatever chemotherapy is used, the results are disappointing. No regimen has proved to be effective in the long run, indeed small cell lung cancer rapidly progresses after a frequent initial strong response, and the mortality rate remains still high. The advent of immunotherapy is actually changing the landscape in oncology. As well as in other cancers, recent trials have demonstrated the efficacy of the combination of immune checkpoint inhibitors and chemotherapy, opening new perspectives for the future of our patients.

Molecular Characterization and Therapeutic Approaches to Small Cell Lung Cancer: Imaging Implications

Small cell lung cancer (SCLC) is a highly aggressive malignancy with exceptionally poor prognosis, comprising approximately 15% of lung cancers. Emerging knowledge of the molecular and genomic landscape of SCLC and recent successful clinical applications of new systemic agents have allowed for precision oncology treatment approaches. Imaging is essential for the diagnosis, staging, and treatment monitoring of patients with SCLC. The role of imaging is increasing with the approval of new treatment agents, including immune checkpoint inhibitors, which lead to novel imaging manifestations of response and toxicities. The purpose of this state-of-the-art review is to provide the reader with the latest information about SCLC, focusing on the subtyping of this malignancy (molecular characterization) and the emerging systemic therapeutic approaches and their implications for imaging. The review will also discuss the future directions of SCLC imaging, radiomics and machine learning.

Head and neck small-cell carcinoma: A multicenter study of 39 cases from 10 institutions

Objective

Basal information of head and neck small-cell carcinoma (HNSmCC) including epidemiology, primary site, treatment, and prognosis remains sparse due to its rarity. We report here a multicenter retrospective study on the diagnosis, treatment, and outcomes of patients with HNSmCC.

Materials and methods

This study involved 47 patients with HNSmCC from 10 participating institutions. Eight patients were excluded for whom no pathological specimens were available (n = 2) and for discrepant central pathological judgements (n = 6). The remaining 39 patients were processed for data analysis.

Results

As pretreatment examinations, computed tomography (CT) was performed for the brain (n = 8), neck (n = 39), and chest (n = 32), magnetic resonance imaging (MRI) for the brain (n = 4) and neck (n = 23), positron emission tomography-CT (PET-CT) in 23 patients, bone scintigraphy in 4, neck ultrasonography in 9, and tumor markers in 25. Primary sites were oral cavity (n = 1), nasal cavity/paranasal sinuses (n = 16), nasopharynx (n = 2), oropharynx (n = 4), hypopharynx (n = 2), larynx (n = 6), salivary gland (n = 3), thyroid (n = 2), and others (n = 3). Stages were II/III/IV-A/IV-B/IV-C/Not determined = 3/5/16/6/5/4; stage IV comprised 69%. No patient had brain metastases. First-line treatments were divided into 3 groups: the chemoradiotherapy (CRT) group (n = 27), non-CRT group (n = 8), and best supportive care group (n = 4). The CRT group included concurrent CRT (CCRT) (n = 17), chemotherapy (Chemo) followed by radiotherapy (RT) (n = 5), and surgery (Surg) followed by CCRT (n = 5). The non-CRT group included Surg followed by RT (n = 2), Surg followed by Chemo (n = 1), RT alone (n = 2), and Chemo alone (n = 3). The 1-year/2-year overall survival (OS) of all 39 patients was 65.3/53.3%. The 1-year OS of the CRT group (77.6%) was significantly better compared with the non-CRT group (31.3%). There were no significant differences in adverse events between the CCRT group (n = 22) and the Chemo without concurrent RT group (n = 9).

Conclusion

Neck and chest CT, neck MRI, and PET-CT would be necessary and sufficient examinations in the diagnostic set up for HNSmCC. CCRT may be recommended as the first-line treatment. The 1-year/2-year OS was 65.3%/53.3%. This study would provide basal data for a proposing the diagnostic and treatment algorithms for HNSmCC.

Research landscape and trends of lung cancer radiotherapy: A bibliometric analysis

Background

radiotherapy is one of the major treatments for lung cancer and has been a hot research area for years. This bibliometric analysis aims to present the research trends on lung cancer radiotherapy.

Method

On August 31, 2022, the authors identified 9868 articles on lung cancer radiotherapy by the Web of Science (Science Citation Indexing Expanded database) and extracted their general information and the total number of citations. A bibliometric analysis was carried out to present the research landscape, demonstrate the research trends, and determine the most cited papers (top-papers) as well as top-journals on lung cancer radiotherapy. After that, the authors analyzed the recent research hotspots based on the latest publications in top-journals.

Results

These 9868 papers were cited a total of 268,068 times. “Durvalumab after chemoradiotherapy in stage III non–small-cell lung cancer” published in 2017 by Antonia et al.was the most cited article (2110 citations). Among the journals, New England Journal of Medicine was most influential. Moreover, J. Clin. Oncol. and Int. J. Radiat. Oncol. Biol. Phys. was both influential and productive. Corresponding authors represented the USA (2610 articles) and China mainland (2060 articles) took part in most publications and articles with corresponding authors from Netherlands were most cited (46.12 citations per paper). Chemoradiotherapy was the hottest research area, and stereotactic body radiotherapy has become a research hotspot since 2006. Radiotherapy plus immunotherapy has been highly focused since 2019.

Conclusions

This bibliometric analysis comprehensively and quantitatively presents the research trends and hotspots based on 9868 relevant articles, and further suggests future research directions. The researchers can benefit in selecting journals and in finding potential collaborators. This study can help researchers gain a comprehensive picture of the research landscape, historical development, and recent hotspots in lung cancer radiotherapy and can provide inspiration for future research.

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

AIMS

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

MATERIALS AND METHODS

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

CLINICALTRIALS

gov was also queried for relevant trials.

RESULTS

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

CONCLUSION

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

Adaptive radiation therapy (art) for patients with limited-stage small cell lung cancer (LS-SCLC): A dosimetric evaluation

Background

Adaptive radiation therapy (ART) refers to redesigning of radiation therapy (RT) treatment plans with respect to dynamic changes in tumor size and location throughout the treatment course. In this study, we performed a comparative volumetric and dosimetric analysis to investigate the impact of ART for patients with limited-stage small cell lung cancer (LS-SCLC).

Methods

Twenty-four patients with LS-SCLC receiving ART and concomitant chemotherapy were included in the study. ART was performed by replanning of patients based on a mid-treatment computed tomography (CT)-simulation which was routinely scheduled for all patients 20-25 days after the initial CT-simulation. While the first 15 RT fractions were planned using the initial CT-simulation images, the latter 15 RT fractions were planned using the mid-treatment CT-simulation images acquired 20-25 days after the initial CT-simulation. In order to document the impact of ART, target and critical organ dose-volume parameters acquired from this adaptive radiation treatment planning (RTP) were compared with the RTP based solely on the initial CT-simulation to deliver the whole RT dose of 60 Gy.

Results

Statistically significant reduction was detected in gross tumor volume (GTV) and planning target volume (PTV) during the conventionally fractionated RT course along with statistically significant reduction in critical organ doses with incorporation of ART.

Conclusion

One-third of the patients in our study who were otherwise ineligible for curative intent RT due to violation of critical organ dose constraints could be treated with full dose irradiation by use of ART. Our results suggest significant benefit of ART for patients with LS-SCLC.

Comparison of Carboplatin With Cisplatin in Small Cell Lung Cancer in US Veterans

IMPORTANCE

The current standard of care for the treatment of small cell lung cancer (SCLC) is concurrent chemoradiation for patients with limited-stage SCLC (LS-SCLC) and chemoimmunotherapy for extensive-stage SCLC (ES-SCLC). The backbone of chemotherapy regimens in both is a platinum-etoposide doublet: cisplatin is traditionally the preferred platinum agent in the curative intent setting, whereas carboplatin is preferred in ES-SCLC because of its favorable toxicity profile.

OBJECTIVE

To determine whether cisplatin is associated with better survival outcomes than carboplatin in treating LS-SCLC and ES-SCLC.

DESIGN, SETTING, AND PARTICIPANTS

In this cohort study, data were compiled from the National Veterans Affairs Central Cancer Registry for patients with SCLC who received platinum-based multiagent chemotherapy between 2000 and 2020 for ES-SCLC and 2000 and 2021 for LS-SCLC. Only patients with pathologically confirmed cases of LS-SCLC who received concurrent chemoradiation and ES-SCLC who received chemotherapy were included.

MAIN OUTCOMES AND MEASURES

The primary end point was overall survival (OS). The secondary end points included OS by Eastern Cooperative Oncology Group performance status, age, and laterality. Interval-censored Weibull and Cox proportional hazard regression models were used to estimate median OS and hazard ratios (HRs), respectively. Survival curves were compared by a Wald test.

RESULTS

A total of 4408 SCLC cases were studied. Most patients were White (3589 patients [81.4%]), male (4252 [96.5%]), and non-Hispanic (4142 [94.0%]); 2262 patients (51.3%) were 60 to 69 years old, followed by 1476 patients (33.5%) aged 70 years or older, 631 patients (14.3%) aged 50 to 59 years, and 39 patients (0.9%) aged 30 to 49 years. Among 2652 patients with ES-SCLC, 2032 were treated with carboplatin-based therapy and 660 received cisplatin; the median OS was 8.45 months (95% CI, 7.75-9.20 months) for cisplatin and 8.51 months (95% CI, 8.07-8.97 months) for carboplatin (HR, 1.01; 95% CI, 0.91-1.12; P = .90). Subset analysis showed no survival difference between the 2 agents in different age or performance status groups except for patients aged 70 years and older, for whom the median OS was 6.36 months (95% CI, 5.31-7.56 months) for cisplatin and 8.47 months (95% CI, 7.79-9.19 months) for carboplatin (HR, 0.77; 95% CI, 0.61-0.96; P = .02). Multivariable analysis of performance status and age did not show a significant difference in survival between the 2 groups (HR, 0.96; 95% CI, 0.83-1.10; P = .54). Of 1756 patients with LS-SCLC, 801 received carboplatin, and 1018 received cisplatin. The median OS was 26.92 months (95% CI, 25.03-28.81 months) for cisplatin and 25.58 months (95% CI, 23.64-27.72 months) for carboplatin (HR, 1.04; 95% CI, 0.94-1.16; P = .46). The median OS was not significantly different between 2 agents according to cancer stage (I-III), performance status, and age groups. A multivariable analysis of factors associated with OS accounting for stage (I-III), performance status, and age did not demonstrate a significant difference in survival between carboplatin and cisplatin in patients with LS-SCLC (HR, 0.995; 95% CI, 0.86-1.15; P = .95).

CONCLUSIONS AND RELEVANCE

Cisplatin is not associated with a survival advantage over carboplatin among patients with either ES-SCLC or LS-SCLC, irrespective of performance status and age. The favorable toxicity profile of carboplatin and comparable OS support its use in both LS-SCLC and ES-SCLC in clinical practice and may allow more room for combination with novel treatment strategies in clinical trials.

The role of surgery in older patients with T1-2N0M0 small cell lung cancer: A propensity score matching analysis

Background

Surgical resection could improve the survival of patients with early-stage small cell lung cancer (SCLC). However, there is a lack of dedicated studies concentrating on surgical treatment in older patients with T1-2N0M0 SCLC. Thus, we performed this population-based study to investigate whether older patients with T1-2N0M0 SCLC could benefit from surgery.

Methods

We collected the data of patients with SCLC between 2000 and 2015 from the Surveillance, Epidemiology, and End Results Program database. Older patients (≥ 65 years) with T1-2N0M0 SCLC were included, and we converted the staging information into those of the eighth edition. The propensity score matching (PSM) was used to balance the distribution of clinical characteristics between surgery and no-surgery groups.

Results

Before PSM, the distribution proportions of clinical characteristics in 1,229 patients were unbalanced. The Kaplan–Meier curves of overall survival (OS) and cancer-specific survival (CSS) showed that the patients in the surgery group were better than those in the non-surgery group (all P &lt; 0.001). After 1:2 PSM, the distribution proportions of clinical characteristics in 683 patients were balanced (all P &gt; 0.05). The OS and CSS of patients in the surgery group were still better than that of patients in the no-surgery group (all P &lt; 0.001), and subgroup analysis showed that the surgery was a protective factor for OS and CSS in all clinical characteristics subgroups (almost P &lt; 0.001). The multivariate Cox analysis further confirmed this result (OS: HR, 0.33; 95% CI, 0.27–0.39; P &lt; 0.001; CSS: HR, 0.29; 95% CI, 0.23–0.36; P &lt; 0.001). The result of subgroup analysis based on age, T stage, and adjuvant therapy showed that surgery was related to better OS and CSS compared with non-surgery group (almost P &lt; 0.001) and that lobectomy exhibited the longer survival than sublobectomy. Age, sex, and race were the independent prognostic factors for OS in patients undergoing surgery, whereas only the factor of age affects the CSS in patients with surgery.

Conclusions

Older patients with T1-2N0M0 SCLC can benefit significantly from surgical treatment, and lobectomy provides better prognosis than sublobectomy.

Primary site as a novel prognostic factor for cardiovascular mortality post-radiotherapy in limited-stage small cell lung cancer: A large population-based study

Background

The effect of primary site on cardiovascular mortality (CVM) post-radiotherapy (RT) in patients with limited-stage small cell lung cancer (LS-SCLC) remains unclear.

Methods

We screened the Surveillance, Epidemiology, and End Results (SEER) database between 1988 and 2013. We used cumulative incidence function (CIF) curves to compare CVM incidences, and performed Cox proportional hazards and Fine-Gray competing risk analyses to identify independent risk factors of CVM. Propensity score matching (PSM) analysis was conducted.

Results

Among enrolled 4,824 patients (median age 57 years old, 49.2% were male), CVM accounts for 10.0% of all deaths after 5 years since cancer diagnosis. Hazard ratios (HRs) for CVM were 1.97 (95% CI: 1.23–3.16, P = 0.005) for main bronchus (MB) patients, 1.65 (95% CI: 1.04–2.63, P = 0.034) for lower lobe (LL) patients and 1.01 (95% CI: 0.40–2.59, P = 0.977) for middle lobe (ML) patients compared to upper lobe (UL) patients. CIF curves showed that the cumulative CVM incidence was greater in the re-categorized MB/LL group compared to UL/ML group both before PSM (P = 0.005) and after PSM (P = 0.012). Multivariate regression models indicated that MB/LL was independently associated with an increased CVM risk, before PSM (HR_Cox: 1.79, 95% CI: 1.23–2.61, P = 0.002; HR_Fine−Gray: 1.71, 95% CI: 1.18–2.48, P = 0.005) and after PSM (HR_Cox: 1.88, 95% CI: 1.20–2.95, P = 0.006; HR_Fine−Gray: 1.79, 95% CI: 1.15–2.79, P = 0.010).

Conclusions

MB/LL as the primary site is independently associated with an increased CVM risk post-RT in patients with LS-SCLC.

Once daily (OD) versus twice-daily (BID) chemoradiation for limited stage small cell lung cancer (LS-SCLC): A meta-analysis of randomized clinical trials

OBJECTIVES

Assess Once daily (OD) chemoradiation effectiveness for LS-SCLC compared with twice daily (BID) chemoradiation.

METHODS AND MATERIALS

Following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline, eligible randomized clinical trials (RCT) comparing OD and BID were identified on electronic databases. A meta-analysis was performed to compare overall survival (OS), progression-free survival (PFS), and toxicity. A metaregression analysis was conducted to explore the influence of fractionation, biological effective dose (BED), the proportion of patients treated with prophylactic cranial irradiation (PCI), elective nodal irradiation (ENI), and the start of radiotherapy (week 1 or week 4).

RESULTS

Five RCTs with a total of 1941 patients (OD vs. BID) were included. The relative risk (RR) for OS and PFS was 0.97 (CI95% 0.8-1.1, p = 0.731) and 0.90 (CI95% 0.7-1.1, p = 0.20) at 3-years. In the metaregression analysis, hypofractionated radiotherapy schedules were associated with an improvement in overall survival (p = 0.03). The start of radiotherapy (W1 or W4), BED, and ENI had no significant effect on OS and PFS. The complete response rate partial response and overall response rate for BID vs OD were 40% vs. 33% (p = 0.97), 50% vs. 57% (p = 0.94), and 89% vs. 93% (p = 0.99). The rate of completed planned RT 96% vs. 94% (p = 0.66), and the % of ≥4 chemotherapy cycles received 74% vs. 74% (p = 0.99), did not differ between OD and BID. The local and distant failure rates were not significantly different between OD and BID 40% vs. 33% (p = 0.88) and 36% vs. 36% (p = 0.99). No difference in grade 2 or grade 3 pneumonitis and esophagitis was observed among the groups (p = NS).

CONCLUSION

For LS-SCLC, OD conventional chemoradiation results in similar outcomes to BID chemoradiation. In contrast, hypofractionated radiotherapy was associated with a better OS and PFS than BID. Additional randomized phase III trials exploring hypofractionation with systemic therapy are warranted to validate our findings.

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.

Novel therapeutic combinations with PARP inhibitors for small cell lung cancer: A bench-to-bedside review

Small cell lung cancer (SCLC) is treated as a monolithic disease despite the evident intra- and intertumoral heterogeneity. Non-specific DNA-damaging agents have remained the first-line treatment for decades. Recently, emerging transcriptomic and genomic profiling of SCLC tumors identified distinct SCLC subtypes and vulnerabilities towards targeted therapeutics, including inhibitors of the nuclear enzyme poly (ADP-ribose) polymerase (PARPi). SCLC cell lines and tumors exhibited an elevated level of PARP1 protein and mRNA compared to healthy lung tissues and other subtypes of lung tumors. Notable responses to PARPi were also observed in preclinical SCLC models. Clinically, PARPi monotherapy exerted variable benefits for SCLC patients. To date, research is being vigorously conducted to examine predictive biomarkers of PARPi response and various PARPi combination strategies to maximize the clinical utility of PARPi. This narrative review summarizes existing preclinical evidence supporting PARPi monotherapy, combination therapy, and respective translation to the clinic. Specifically, we covered the combination of PARPi with DNA-damaging chemotherapy (cisplatin, etoposide, temozolomide), thoracic radiotherapy, immunotherapy (immune checkpoint inhibitors), and many other novel therapeutic agents that target DNA damage response, tumor microenvironment, epigenetic modulation, angiogenesis, the ubiquitin-proteasome system, or autophagy. Putative biomarkers, such as SLFN11 expression, MGMT methylation, E2F1 expression, and platinum sensitivity, which may be predictive of response to distinct therapeutic combinations, were also discussed. The future of SCLC treatment is undergoing rapid change with a focus on tailored and personalized treatment strategies. Further development of cancer therapy with PARPi will immensely benefit at least a subset of biomarker-defined SCLC patients.

The Construction and Validation of Nomogram to Predict the Prognosis with Small-Cell Lung Cancer Followed Surgery

This study constructed and validated a prognostic model to evaluate the survival of small-cell lung cancer (SCLC) patients following surgery, and shed light on the strategy of postoperative radiotherapy. A total of 882 patients from Shanghai Pulmonary Hospital and the Surveillance, Epidemiology and End Results database after lung resection were selected. Multivariable Cox analysis was used to identify the indicators affecting long-term survival in patients. A nomogram was constructed to predict the prognosis of eligible patients. Indices of concordance (C-index) was used to access the predictive ability of cancer-specific survival (CSS) for the prognostic model. CSS discrimination in the prognostic model was comparable in the training and validation cohorts (C-index = 0.637[NORAD-T], 0.660[NORAD-V], 0.656[RAD] and 0.627[our hospital], respectively. Stratification based on the cutoff value of the nomogram yielded low- and high-risk subgroups in four cohorts. For patients in the high-risk group, postoperative radiotherapy was considered a survival-promoting strategy (unadjusted HR 0.641, 95% CI 0.469-0.876, p = 0.0046). In the low-risk group, however, the implementation of radiotherapy barely had an influence on CSS. In conclusion, the nomogram we constructed and validated could predict the prognosis of SCLC patients followed surgery and identify high-risk patients who were likely to benefit from postoperative radiotherapy.

New perspectives in the management of small cell lung cancer

The treatment of small cell lung cancer (SCLC) is a challenge for all specialists involved. New treatments have been added to the therapeutic armamentarium in recent months, but efforts must continue to improve both survival and quality of life. Advances in surgery and radiotherapy have resulted in prolonged survival times and fewer complications, while more careful patient selection has led to increased staging accuracy. Developments in the field of systemic therapy have resulted in changes to clinical guidelines and the management of patients with advanced disease, mainly with the introduction of immunotherapy. In this article, we describe recent improvements in the management of patients with SCLC, review current treatments, and discuss future lines of research.

Society for Immunotherapy of Cancer (SITC) clinical practice guideline on immunotherapy for the treatment of lung cancer and mesothelioma

Immunotherapy has transformed lung cancer care in recent years. In addition to providing durable responses and prolonged survival outcomes for a subset of patients with heavily pretreated non-small cell lung cancer (NSCLC), immune checkpoint inhibitors (ICIs)— either as monotherapy or in combination with other ICIs or chemotherapy—have demonstrated benefits in first-line therapy for advanced disease, the neoadjuvant and adjuvant settings, as well as in additional thoracic malignancies such as small-cell lung cancer (SCLC) and mesothelioma. Challenging questions remain, however, on topics including therapy selection, appropriate biomarker-based identification of patients who may derive benefit, the use of immunotherapy in special populations such as people with autoimmune disorders, and toxicity management. Patient and caregiver education and support for quality of life (QOL) is also important to attain maximal benefit with immunotherapy. To provide guidance to the oncology community on these and other important concerns, the Society for Immunotherapy of Cancer (SITC) convened a multidisciplinary panel of experts to develop a clinical practice guideline (CPG). This CPG represents an update to SITC’s 2018 publication on immunotherapy for the treatment of NSCLC, and is expanded to include recommendations on SCLC and mesothelioma. The Expert Panel drew on the published literature as well as their clinical experience to develop recommendations for healthcare professionals on these important aspects of immunotherapeutic treatment for lung cancer and mesothelioma, including diagnostic testing, treatment planning, immune-related adverse events, and patient QOL considerations. The evidence- and consensus-based recommendations in this CPG are intended to give guidance to cancer care providers using immunotherapy to treat patients with lung cancer or mesothelioma.

Optimal timing of thoracic irradiation for limited stage small cell lung cancer: Current evidence and future prospects

Lung cancer is a global health concern as the leading cause of cancer related mortality worldwide. Small cell lung cancer (SCLC) poses a formidable challenge to the treating physicians with the worst prognosis among all lung cancers. However, limited stage SCLC (LS-SCLC) has a relatively better outcome with multimodality management. Efforts have been focused on optimal integration of treatment modalities to achieve an improved therapeutic ratio for patients with LS-SCLC. While chemotherapy and thoracic radiation therapy (TRT) are primary components of initial management for LS-SCLC, there is no consensus on optimal timing of TRT. Within this context, we herein provide a concise overview of current evidence and future prospects regarding the optimal timing of thoracic irradiation for LS-SCLC in light of the literature.

Radiation and Systemic Therapy for Limited-Stage Small-Cell Lung Cancer

Progress in the overall treatment of small-cell lung cancer (SCLC) has moved at a slower pace than non-small-cell lung cancer. In fact, the standard treatment regimen for limited stage SCLC has not appreciably shifted in more than 20 years, consisting of four to six cycles of cisplatin and etoposide chemotherapy concurrent with thoracic radiotherapy (TRT) followed by prophylactic cranial irradiation (PCI) for responsive disease. Nevertheless, long-term outcomes have improved with median survival approaching 25-30 months, and approximately one third of patients now survive 5 years. This is likely attributable in part to improvements in staging, including use of brain magnetic resonance imaging and fluorodeoxyglucose-positron emission tomography imaging, advances in radiation treatment planning, and supportive care. The CONVERT and CALGB 30610 phase III trials failed to demonstrate a survival advantage for high-dose, once-daily TRT compared with standard 45 Gy twice-daily TRT, although high-dose, once-daily TRT remains common in practice. A phase III comparison of high-dose 60 Gy twice-daily TRT versus 45 Gy twice-daily TRT aims to confirm the provocative outcomes reported with 60 Gy twice daily in the phase II setting. Efforts over time have shifted from intensifying PCI, to attempting to reduce treatment-related neurotoxicity, to more recently questioning whether careful magnetic resonance imaging surveillance may obviate the routine need for PCI. The addition of immunotherapy has resulted in mixed success in extensive-stage SCLC with modest benefit observed with programmed death-ligand 1 inhibitors, and several ongoing trials assess programmed death-ligand 1 inhibition concurrent or adjuvant to chemoradiotherapy in limited-stage SCLC. Major advances in future treatment will likely depend on a better understanding and exploiting of molecular characteristics of SCLC with increasing personalization of therapy.

Limited-Stage Small-Cell Lung Cancer: Current Progress and the Next Frontier

Limited-stage (LS) small-cell lung cancer (SCLC) is defined as disease confined to a tolerable radiation portal without extrathoracic metastases. Despite clinical research over two decades, the prognosis of LS-SCLC patients remains poor. The current standard of care for LS-SCLC patients is concurrent platinum-based chemotherapy with thoracic radiotherapy (RT). Widespread heterogeneity on the optimal radiation dose and fractionation regimen among physicians highlights the logistical challenges of administering BID regimens. Prophylactic cranial irradiation (PCI) is recommended to patients following a good initial response to chemoradiation due to improved overall survival from historical trials and the propensity for LS-SCLC to recur with brain metastases. However, PCI utilization is being debated due to the greater availability of magnetic resonance imaging (MRI) and data in extensive-stage SCLC regarding close MRI surveillance in lieu of PCI while spurring novel RT techniques, such as hippocampal-avoidance PCI. Additionally, novel treatment combinations incorporating targeted small molecule therapies and immunotherapies with or following radiation for LS-SCLC have seen recent interest and some concepts are being investigated in clinical trials. Here, we review the landscape of progress, limitations, and challenges for LS-SCLC including current standard of care, novel radiation techniques, and the integration of novel therapeutic strategies for LS-SCLC.

Radiotherapy for primary lung cancer

Herein are presented the recommendations from the Société française de radiothérapie oncologique regarding indications and modalities of lung cancer radiotherapy. The recommendations for delineation of the target volumes and organs at risk are detailed.

Preliminary Safety and Efficacy of Proton Plus Carbon-Ion Radiotherapy With Concurrent Chemotherapy in Limited-Stage Small Cell Lung Cancer

Objectives

This study aimed to investigate the tolerance and effect of proton plus carbon-ion radiotherapy with concurrent chemotherapy in limited-stage small cell lung cancer using the pencil beam scanning technique.

Materials and Methods

From March 2017 to April 2020, 25 patients with limited-stage small cell lung cancer treated with combined proton and carbon-ion radiotherapy were analyzed. The primary lesions and involved lymph nodes were irradiated using 2-4 portals. Proton and sequential carbon-ion beams were delivered with a median dose of 67.1 (range, 63-74.8) GyE as fraction doses of 2.0-2.2 GyE with proton beams in 20-23 fractions and 3.0-3.8 GyE with carbon ions in 5-8 fractions. Chemotherapy was delivered concurrently with radiotherapy in all patients.

Results

At the last follow-up, the 2-year overall and locoregional progression-free survival rates were 81.7% and 66.7%, respectively. Radiochemotherapy was well tolerated, with grade 1, 2, and 3 acute toxicities occurring in 12.0%, 68.0%, and 20.0% of patients, respectively. All grade 3 acute toxicities were hematologically related changes. One patient experienced grade 3 acute non-hematological toxicity in the esophagus, and one other patient had grade 3 bronchial obstruction accompanied by obstructive atelectasis as a late side effect.

Conclusion

Proton plus carbon-ion radiotherapy using pencil beam scanning yielded promising survival rates and tolerability in patients with limited-stage small cell lung cancer. A prospective clinical study is warranted to validate the therapeutic efficacy of particle radiotherapy in combination with chemotherapy in limited-stage small cell lung cancer.

Thoracic Radiotherapy in Limited-Stage Small-Cell Lung Cancer – a Population-Based Study of Patterns of Care in Norway from 2000 until 2018

Introduction

Twice-daily (BID) thoracic radiotherapy (TRT) of 45 Gy per 30 fractions is recommended for limited-stage (LS) SCLC, but most patients are treated with once-daily (OD) schedules owing to toxicity concerns and logistic challenges. An alternative is hypofractionated OD TRT of 40 to 42 Gy per 15 fractions. A randomized trial by our group indicated that TRT of 45 Gy per 30 fractions is more effective than TRT of 42 Gy per 15 fractions, and because it was not more toxic, 45 BID replaced 42 OD as the recommended schedule in Norway. The aims of this study were to evaluate to what extent BID TRT has been implemented in Norway and whether this practice change has led to improved survival.

Methods

Data on all patients diagnosed with LS SCLC from 2000 until 2018 were collected from the Cancer Registry of Norway, containing nearly complete data on cancer diagnosis, radiotherapy, and survival.

Results

A total of 2222 patients were identified; median age was 69 years, 51.8% were women, and 87.1% had stage II to III disease. Overall, 64.6% received TRT. The use of BID TRT increased from 1.8% (2000–2004) to 83.2% (2015–2018). Median overall survival among patients receiving curative TRT improved significantly during the study period (2000–2004: 17.9 mo, 2015–2018: 25.0 mo, p = 0.0023), and patients receiving 45 BID had significantly longer median overall survival than patients receiving 42 OD (BID: 26.2 mo, OD: 19.6 mo, p = 0.0015).

Conclusions

BID TRT has replaced hypofractionated OD TRT as the standard treatment of LS SCLC in Norway which has led to a significant (p = 0.0023) and clinically relevant survival improvement.