Role of Adjuvant Therapy in a Population-Based Cohort of Patients With Early-Stage Small-Cell Lung Cancer

Prophylactic cranial irradiation improved the prognosis in pT1-2N0M0 small cell lung cancers after complete resection: a retrospective real-world study

BACKGROUND

The efficacy of prophylactic cranial irradiation (PCI) is still controversial in small cell lung cancer (SCLC) patients with pT1-2N0M0 disease after complete resection. The majority of previous studies haven't discerned the potential benefit of PCI in this subgroup of patients, probably due to the paucity of these patients and distinct treating modalities. The aim of this study is to demonstrate the potential medical benefit of PCI in these patients.

METHODS

A retrospective study was conducted to evaluate the potential benefit of PCI in pT1-2N0M0 SCLC patients after complete resection. We retrospectively reviewed 112 pT1-2N0M0 SCLCs after complete resection and adjuvant chemotherapy between January 2013 and January 2022. Survival and Cox regression analysis were conducted to elucidate the potential medical benefit of PCI in these patients.

RESULTS

The median overall survival (OS) has not been reached. The 2-year, 5-year, 8-year OS rate was 93.7%, 73.2%, and 65.7%, respectively. Brain metastasis (BM) was observed in 17.0% (19/112) patients during the process of follow-up. PCI significantly decreased the BM actuarial risk from 23.9 to 4.9% (log-rank p = 0.0097, HR = 0.180, 95% CI: 0.041-0.778). The brain metastasis free survival (BMFS, log-rank p = 0.02) and OS (log-rank p = 0.05) in PCI cohort were also significantly longer than that of non_PCI group. Cox analysis demonstrated that PCI was an independent prognostic factor in both BM actuarial risk (HR = 0.198, 95% CI: 0.046-0.859, p = 0.031) and BMFS (HR = 0.387, 95% CI: 0.169-0.890, p = 0.025). Moreover, T2 patients showed a significant superior prognosis in terms of BM actuarial risk with comparison to those with T1 disease in non_PCI cohort (log-rank p = 0.016, HR = 3.345, 95% CI: 1.177-9.511), whereas the difference could not be observed in PCI cohort.

CONCLUSIONS

PCI was significantly associated with a better clinical outcome in pT1-2N0M0 SCLC patients who received complete resection and adjuvant chemotherapy, especially in T2 patients.

Survival outcomes of surgery and adjuvant chemotherapy in early-stage small cell and large cell lung cancer: a novel focus on tumors less than 1 cm

BACKGROUND

The role of adjuvant chemotherapy in early-stage small cell lung cancer (SCLC) and large cell neuroendocrine carcinoma (LCNEC) remains unclear, particularly for small tumors. This study assesses the survival benefits of adjuvant chemotherapy after surgical resection with a novel focus on tumors less than 1 cm.

MATERIALS AND METHODS

Data from the National Cancer Database (NCDB) was extracted for patients with SCLC (n = 11,962) and LCNEC (n = 6821) who underwent surgical resection between 2004 and 2020. Exclusion criteria were limited survival (< 30 days), positive lymph nodes, distant metastases, large tumors (> 5 cm), residual microscopic disease, and neoadjuvant therapy. The primary outcome was overall survival (OS) from diagnosis, which was evaluated using Kaplan-Meier methods and multivariate Cox regression analyses. A propensity score matching (PSM) analysis was performed to compare outcomes in patients with SCLC and tumors ≤ 1 cm who received adjuvant chemotherapy versus surgery alone.

RESULTS

The study involved 4114 SCLC and 3954 LCNEC patients. Adjuvant chemotherapy was associated with a significant increase median OS in both SCLC (6.26 vs. 4.18 years; p < 0.001) and LCNEC (7.02 years vs. 4.89 years; p < 0.001), while also being an independent predictor of better OS in SCLC (HR: 0.74) and LCNEC (HR: 0.75) (p < 0.001). The benefit was more noticeable in tumors ≤ 1 cm, showing a significant OS increase after PSM (median OS 7.34 vs. 5.02 years; p = 0.0048).

CONCLUSION

Adjuvant chemotherapy after surgery is associated with improved overall survival in stage I SCLC and LCNEC, particularly in SCLC tumors of 1 cm or less.

Prophylactic cranial irradiation for small cell lung cancer in the era of immunotherapy and molecular subtypes

PURPOSE OF REVIEW

Small cell lung cancer (SCLC) is an aggressive disease with a poor prognosis, whereas its metastatic capacity carries a predilection for the brain. Although prophylactic cranial irradiation (PCI) has been used to address this problem, upcoming alternatives might necessitate reflection of its application in SCLC treatment.

RECENT FINDINGS

The addition of immunotherapy to treatment guidelines has provided a new strategy for the management of brain metastases. Complementation of immunotherapy with active MRI surveillance could potentially replace PCI and avoid irradiation-related cognitive side effects. SCLC's molecular profile is heterogeneous, with differential response to treatment modalities between subgroups. Investigation of these variances might be essential to improve therapeutic outcomes in SCLC patients.

SUMMARY

The role of PCI in SCLC treatment must be examined in light of immunotherapy. We summarize recent results, bearing SCLC subtypes and therapeutic vulnerabilities in mind, to derive tailored treatment strategies for SCLC patients in future settings.

Proteomic profiling reveals the significance of lipid metabolism in small cell lung cancer recurrence and metastasis

BACKGROUND

Small cell lung cancer (SCLC) is a lethal and recalcitrant malignancy with early metastases. However, the molecular and cellular mechanisms underlying its aggressive characteristics remain relatively elusive.

METHODS

In this study, we conducted a comprehensive proteomic analysis of 90 primary tumors, 15 patient-matched lymph node metastatic tumors, and 15 brain metastatic tumors derived from a cohort of 105 SCLC patients. The potential mechanism for SCLC metastasis was investigated based on the variety of protein expression profiles.

RESULTS

Primary tumors were divided into two categories according to the their different protein expression profiles, using metastatic tumors as reference. Proteomic comparisons across different groups revealed that lipid metabolism, especially phospholipid metabolism, and immune response had a critical role in SCLC metastasis. Additionally, it was shown that high- and low-density lipoprotein cholesterol were both independent prognostic factors for disease free survival of SCLC patients. To identify critical regulators of metastasis in SCLC, support vector machine was adopted to generate a biomarker combination of ten proteins, all of which significantly correlated with the infiltration of immune cells. Furthermore, it was demonstrated that high expression of phospholipase A2 group IIA in stroma was associated with delayed disease recurrence in limited stage SCLC.

CONCLUSIONS

This study highlighted the critical significance of lipid metabolism, especially phospholipid metabolism in the disease recurrence and metastasis of SCLC.

Berberine and Lung Cancer: From Pure Form to Its Nanoformulations

Lung cancer is the most fatal cancer worldwide. The etiology of lung cancer has yet to be fully characterized. Smoking and air pollution are several risk factors for lung cancer. Berberine, an isoquinoline alkaloid, is an antihyperglycemic, antidepressant, antioxidative, anti-inflammatory, and anticancer compound. Evidence substantiates that berberine has antitumor effects, exerting its effects by targeting a variety of cellular and molecular processes, such as apoptosis, autophagy, cell cycle arrest, migration, and metastasis. Although the beneficial effects of berberine have been reported, some limitations including low bioavailability and absorption as well as poor aqueous solubility have hindered its clinical application. Nanotechnology and nanodelivery bioformulation approaches may bypass these limitations. In addition, the combination of berberine with other therapies has been shown to result in greater treatment efficacy for lung cancer. Herein, we summarize cellular and molecular pathways that are affected by berberine, its clinical efficacy upon various combinations, and the potential for nanotechnology in lung cancer therapy.

Prophylactic cranial irradiation in patients with resected small-cell lung cancer: A systematic review and meta-analysis

Prophylactic cranial irradiation (PCI) was recommended for limited-stage small-cell lung cancer (SCLC) patients with complete or partial response to primary chemoradiotherapy. But it is still controversial regarding its role in SCLC patients who have had radical resection. This meta-analysis aims to evaluate the efficacy of PCI in resected SCLC patients. We searched PubMed, EMBASE, Web of Science, CENTRAl, and ClinicalTrials for controlled trials and cohort studies regarding PCI in postoperative SCLC patients. The correlation between PCI and post-operative outcomes in SCLC patients, including survival and brain metastasis rate (BMR), was examined using hazard ratios (HRs) and risk ratios with corresponding 95% confidence intervals. Quality of studies was assessed by the Newcastle-Ottawa Scale (NOS), and publication bias was assessed by Begg's test. Meta-analysis of eight studies with 2688 patients in total showed PCI was associated with improved overall survival (OS) for resected SCLC (HR: 0.65, 95% CI: 0.57-0.75, p < 0.01). In addition, subgroup analysis on three studies including 923 patients confirmed the protective role of postoperative PCI in N0 SCLC patients (HR: 0.79, 95% CI: 0.61-0.97, p < 0.05). There was also a significant reduction in BMR in the PCI group pooled from six studies (HR: 0.58, 95% CI: 0.40-0.85, p < 0.01). The use of PCI delayed brain recurrence and improved OS in patients with resected, stage I-III SCLC. Importantly, patients with N0 SCLC can also benefit from postoperative PCI. In future studies, PCI's role in patients with resected N0 SCLC at different T stage may need to be explored.

Role of Surgery in Potentially Resectable Small-Cell Lung Cancer Based on the Eighth Edition of the TNM Classification: A Population Study of the US SEER Database

BACKGROUND

This study aimed to identify a specific SCLC population that would benefit from surgery.

METHODS

This study utilized patient data retrieved from the Surveillance, Epidemiology, and End Results (SEER) database spanning 2010 to 2017. To mitigate clinical biases, the propensity score matching (PSM) technique was employed. Separate cohorts were aligned using PSM according to the AJCC 8th edition TNM classification. The Kaplan-Meier method and a competing risk model were applied to evaluate overall survival (OS) and lung cancer-specific survival (LCSS), respectively.

OUTCOMES

Among the 3394 patients with potentially resectable SCLC included in the study, 3062 underwent chemoradiotherapy and 332 underwent surgical treatment with adjuvant chemotherapy. Surgery was associated with better OS (median OS: 49 months; 95% CI: 35-63 months vs. 27 months; 95% CI: 21-33 months, p < 0.001) and LCSS (SHR, 0.578; 95% CI: 0.411-0.815, p < 0.001) in stage I patients after PSM. However, there was no significant difference in OS and LCSS between the surgery and nonsurgery groups in stage II and III patients after PSM. In the entire cohort, lobectomy was associated with improved OS (median OS: 48.6 vs. 28.7 months, p < 0.0001), but not LCSS (SHR, 0.696; 95% CI: 0.466-1.040, p = 0.078) compared with sublobar resection after PSM.

CONCLUSION

Surgery with adjuvant chemotherapy significantly improved the survival prognosis of patients with early-stage SCLC. However, surgical treatment should be carefully considered in patients with stage II/III disease. Lobectomy is oncologically equal to sublobar resection.

Prognostic impact of interstitial lung disease on pulmonary high-grade neuroendocrine carcinoma

Pulmonary high-grade neuroendocrine carcinomas (HGNECs) have poor prognoses and require multimodal treatment, and interstitial lung disease (ILD) restricts sufficient treatment of patients with lung cancer. We aimed to clarify ILD's prognostic impact on pulmonary HGNEC, which has previously gone unreported. We retrospectively analyzed 53 patients with HGNEC who underwent resections at our department between 2006 and 2021 and evaluated the clinicopathological prognostic features, including ILD. The patients' mean age was 70 years; 46 (87%) were male, and all were smokers. Large-cell neuroendocrine and small-cell lung carcinomas were diagnosed in 36 (68%) and 17 (32%) patients, respectively. The pathological stages were stage I, II, and III in 31 (58%), 11 (21%), and 11 (21%) patients, respectively. Nine patients (17%) had ILD, which was a significant overall survival prognostic factor in a multivariate Cox proportional hazards regression analysis (p = 0.048), along with lymph node metastasis (p = 0.004) and non-administration of platinum-based adjuvant chemotherapy (p = 0.003). The 5 year survival rate of the ILD patients was 0%, significantly worse than that of patients without ILD (58.7%; p = 0.003). Patients with HGNEC and ILD had a poor prognosis owing to adjuvant therapy's limited availability for recurrence and the development of acute exacerbations associated with ILD.

Incidence rate of occult lymph node metastasis in clinical T1-2N0M0 small cell lung cancer patients and radiomic prediction based on contrast-enhanced CT imaging: a multicenter study : Original research

BACKGROUND

This study aimed to explore the incidence of occult lymph node metastasis (OLM) in clinical T1 - 2N0M0 (cT1 - 2N0M0) small cell lung cancer (SCLC) patients and develop machine learning prediction models using preoperative intratumoral and peritumoral contrast-enhanced CT-based radiomic data.

METHODS

By conducting a retrospective analysis involving 242 eligible patients from 4 centeres, we determined the incidence of OLM in cT1 - 2N0M0 SCLC patients. For each lesion, two ROIs were defined using the gross tumour volume (GTV) and peritumoral volume 15 mm around the tumour (PTV). By extracting a comprehensive set of 1595 enhanced CT-based radiomic features individually from the GTV and PTV, five models were constucted and we rigorously evaluated the model performance using various metrics, including the area under the curve (AUC), accuracy, sensitivity, specificity, calibration curve, and decision curve analysis (DCA). For enhanced clinical applicability, we formulated a nomogram that integrates clinical parameters and the rad_score (GTV and PTV).

RESULTS

The initial investigation revealed a 33.9% OLM positivity rate in cT1 - 2N0M0 SCLC patients. Our combined model, which incorporates three radiomic features from the GTV and PTV, along with two clinical parameters (smoking status and shape), exhibited robust predictive capabilities. With a peak AUC value of 0.772 in the external validation cohort, the model outperformed the alternative models. The nomogram significantly enhanced diagnostic precision for radiologists and added substantial value to the clinical decision-making process for cT1 - 2N0M0 SCLC patients.

CONCLUSIONS

The incidence of OLM in SCLC patients surpassed that in non-small cell lung cancer patients. The combined model demonstrated a notable generalization effect, effectively distinguishing between positive and negative OLMs in a noninvasive manner, thereby guiding individualized clinical decisions for patients with cT1 - 2N0M0 SCLC.

The Dose/Fractionation Debate in Limited-Stage Small Cell Lung Cancer

To explore the most suitable dosage regimen for limited-stage small cell lung cancer (LS-SCLC) and provide references for clinical selection, strict inclusion criteria were applied, and studies were screened from Pubmed, Embase, and Web of Science. Subsequently, data on two-year overall survival rates and dosage regimens were collected, and scatter plots were constructed to provide a comprehensive perspective. The survival benefits of various dosage regimens were evaluated, and a linear quadratic equation was utilized to fit the relationship between the biologically effective dose (BED10) and the two-year overall survival rate. Among the five randomized controlled trials, the two-year overall survival rate of ConvTRT regimens with BED10 > 60 Gy (rough value) was only at or below the median of all ConvTRT regimens or all included study regimens, indicating that increasing the number and total dose of ConvTRT does not necessarily lead to better prognosis. In the exploration of HypoTRT regimens, there was a linear positive correlation between BED10 and the two-year overall survival rate (p < 0.0001), while the exploration of HyperTRT regimens was relatively limited, with the majority focused on the 45 Gy/30 F regimen. However, the current 45 Gy/30 F regimen is not sufficient to control LS-SCLC, resulting in a high local recurrence rate. High-dose ConvTRT regimens have long treatment durations and may induce tumor regrowth which may cause reduced efficacy. Under reasonable toxicity reactions, HyperTRT or HypoTRT with higher radiotherapy doses is recommended for treating LS-SCLC.

CD3, CD8, IFN-γ, tumor and stroma inflammatory cells as prognostic indicators for surgically resected SCLC: evidences from a 10-year retrospective study and immunohistochemical analysis

Current clinical guidelines limit surgical intervention to patients with cT1-2N0M0 small cell lung cancer (SCLC). Our objective was to reassess the role of surgery in SCLC management, and explore novel prognostic indicators for surgically resected SCLC. We reviewed all patients diagnosed with SCLC from January 2011 to April 2021 in our institution. Survival analysis was conducted using the Kaplan-Meier method, and independent prognostic factors were assessed through the Cox proportional hazard model. In addition, immunohistochemistry (IHC) staining was performed to evaluate the predictive value of selected indicators in the prognosis of surgically resected SCLC patients. In the study, 177 SCLC patients undergoing surgical resection were ultimately included. Both univariate and multivariate Cox analysis revealed that incomplete postoperative adjuvant therapy emerged as an independent risk factor for adverse prognosis (p < 0.001, HR 2.96). Survival analysis revealed significantly superior survival among pN0-1 patients compared to pN2 patients (p < 0.0001). No significant difference in postoperative survival was observed between pN1 and pN0 patients (p = 0.062). Patients with postoperative stable disease (SD) exhibited lower levels of tumor inflammatory cells (TIC) (p = 0.0047) and IFN-γ expression in both area and intensity (p < 0.0001 and 0.0091, respectively) compared to those with postoperative progressive disease (PD). Conversely, patients with postoperative SD showed elevated levels of stromal inflammatory cells (SIC) (p = 0.0453) and increased counts of CD3+ and CD8+ cells (p = 0.0262 and 0.0330, respectively). Survival analysis indicated that high levels of SIC, along with low levels of IFN-γ+ cell area within tumor tissue, may correlate positively with improved prognosis in surgically resected SCLC (p = 0.017 and 0.012, respectively). In conclusion, the present study revealed that the patients with pT1-2N1M0 staging were a potential subgroup of SCLC patients who may benefit from surgery. Complete postoperative adjuvant therapy remains an independent factor promoting a better prognosis for SCLC patients undergoing surgical resection. Moreover, CD3, CD8, IFN-γ, TIC, and SIC may serve as potential indicators for predicting the prognosis of surgically resected SCLC.

Nomograms Predict PFS and OS for SCLC Patients After Standardized Treatment: A Real-World Study

Purpose

This study aims to investigate the process of small cell lung cancer (SCLC) patients from achieving optimal efficacy to experiencing disease progression until death. It examines the predictive value of the treatment response on progression free survival (PFS) and overall survival (OS) of SCLC patients.

Patients and Methods

We conducted a retrospective analysis on 136 SCLC patients diagnosed from 1992 to 2018. Important prognostic factors were identified to construct nomogram models. The predictive performance of the models was evaluated using the receiver operating characteristic curves and calibration curves. Survival differences between groups were compared using Kaplan-Meier survival curves. Subsequently, an independent cohort consisting of 106 SCLC patients diagnosed from 2014 to 2021 was used for validation.

Results

We constructed two nomograms to predict first-line PFS (PFS1) and OS of SCLC. The area under the receiver operating characteristic curves for the PFS1 nomogram predicting PFS at 3-, 6-, and 12-months were 0.919 (95% CI: 0.867-0.970), 0.908 (95% CI: 0.860-0.956) and 0.878 (95% CI: 0.798-0.958), and for the OS nomogram predicting OS at 6-, 12-, and 24-months were 0.814 (95% CI: 0.736-0.892), 0.819 (95% CI: 0.749-0.889) and 0.809 (95% CI: 0.678-0.941), indicating those two models with a high discriminative ability. The calibration curves demonstrated the models had a high degree of consistency between predicted and observed values. According to the risk scores, patients were divided into high-risk and low-risk groups, showing a significant difference in survival rate. And these findings were validated in another independent validation cohort.

Conclusion

Based on the patients' treatment response after standardized treatment, we developed and validated two nomogram models to predict PFS1 and OS of SCLC. The models demonstrated good accuracy, reliability and clinical applicability by validating in an independent cohort.

Acquired Cross-Resistance in Small Cell Lung Cancer due to Extrachromosomal DNA Amplification of MYC Paralogs

Small cell lung cancer (SCLC) presents as a highly chemosensitive malignancy but acquires cross-resistance after relapse. This transformation is nearly inevitable in patients but has been difficult to capture in laboratory models. Here, we present a preclinical system that recapitulates acquired cross-resistance, developed from 51 patient-derived xenograft (PDX) models. Each model was tested in vivo against three clinical regimens: cisplatin plus etoposide, olaparib plus temozolomide, and topotecan. These drug-response profiles captured hallmark clinical features of SCLC, such as the emergence of treatment-refractory disease after early relapse. For one patient, serial PDX models revealed that cross-resistance was acquired through MYC amplification on extrachromosomal DNA (ecDNA). Genomic and transcriptional profiles of the full PDX panel revealed that MYC paralog amplifications on ecDNAs were recurrent in relapsed cross-resistant SCLC, and this was corroborated in tumor biopsies from relapsed patients. We conclude that ecDNAs with MYC paralogs are recurrent drivers of cross-resistance in SCLC.

SIGNIFICANCE

SCLC is initially chemosensitive, but acquired cross-resistance renders this disease refractory to further treatment and ultimately fatal. The genomic drivers of this transformation are unknown. We use a population of PDX models to discover that amplifications of MYC paralogs on ecDNA are recurrent drivers of acquired cross-resistance in SCLC. This article is featured in Selected Articles from This Issue, p. 695.

C-Myc protein expression indicates unfavorable clinical outcome in surgically resected small cell lung cancer

BACKGROUND

By being highly involved in the tumor evolution and disease progression of small cell lung cancer (SCLC), Myc family members (C-Myc, L-Myc, and N-Myc) might represent promising targetable molecules. Our aim was to investigate the expression pattern and prognostic relevance of these oncogenic proteins in an international cohort of surgically resected SCLC tumors.

METHODS

Clinicopathological data and surgically resected tissue specimens from 104 SCLC patients were collected from two collaborating European institutes. Tissue sections were stained by immunohistochemistry (IHC) for all three Myc family members and the recently introduced SCLC molecular subtype-markers (ASCL1, NEUROD1, POU2F3, and YAP1).

RESULTS

IHC analysis showed C-Myc, L-Myc, and N-Myc positivity in 48%, 63%, and 9% of the specimens, respectively. N-Myc positivity significantly correlated with the POU2F3-defined molecular subtype (r = 0.6913, p = 0.0056). SCLC patients with C-Myc positive tumors exhibited significantly worse overall survival (OS) (20 vs. 44 months compared to those with C-Myc negative tumors, p = 0.0176). Ultimately, in a multivariate risk model adjusted for clinicopathological and treatment confounders, positive C-Myc expression was confirmed as an independent prognosticator of impaired OS (HR 1.811, CI 95% 1.054-3.113, p = 0.032).

CONCLUSIONS

Our study provides insights into the clinical aspects of Myc family members in surgically resected SCLC tumors. Notably, besides showing that positivity of Myc family members varies across the patients, we also reveal that C-Myc protein expression independently correlates with worse survival outcomes. Further studies are warranted to investigate the role of Myc family members as potential prognostic and predictive markers in this hard-to-treat disease.

Systemic Therapy for Small-Cell Lung Cancer: ASCO-Ontario Health (Cancer Care Ontario) Guideline

PURPOSE

To provide evidence-based recommendations to practicing clinicians on the management of patients with small-cell lung cancer.

METHODS

An Expert Panel of medical oncology, thoracic surgery, radiation oncology, pulmonary, community oncology, research methodology, and advocacy experts were convened to conduct a literature search, which included systematic reviews, meta-analyses, and randomized controlled trials published from 1990 through 2022. Outcomes of interest included response rates, overall survival, disease-free survival or recurrence-free survival, and quality of life. Expert Panel members used available evidence and informal consensus to develop evidence-based guideline recommendations.

RESULTS

The literature search identified 95 relevant studies to inform the evidence base for this guideline.

RECOMMENDATIONS

Evidence-based recommendations were developed to address systemic therapy options, timing of therapy, treatment in patients who are older or with poor performance status, role of biomarkers, and use of myeloid-supporting agents in patients with small-cell lung cancer.Additional information is available at www.asco.org/thoracic-cancer-guidelines.

Time to treatment patterns of head and neck cancer patients before and during the Covid-19 pandemic

OBJECTIVES

The delivery of healthcare has changed significantly over the past decades. This study analyzes the clinicodemographic factors and treatment patterns of head and neck squamous cell carcinoma (HNSCC) patients between 2004 and 2020.

MATERIALS AND METHODS

Retrospective cohort analysis of HNSCC patients from the National Cancer Data Base from 2004 to 2020.

RESULTS

A total of 164,290 patients were included. Increased times from diagnosis to definitive surgery (TTS) were seen across all facility types (academic centers, AC; non-academic centers, NAC) between 2004 and 2019, with NAC affected more. TTS < 15 days (RR = 1.05, 95%CI:1.05-1.09) and > 75 days (1.07, 95%CI:1.05-1.09) were associated with increased mortality risk. This association was more prominent among HPV + HNSCC (RR = 1.45; 95%CI:1.18-1.78). Treatment in AC was associated with a decreased mortality risk (RR = 0.94, 95%CI:0.93-0.95). Despite the universal increase in wait times from 2004 to 2019, short-term mortality was significantly decreased from 2016 to 2019, relative to 2004-2007 (3-month mortality: RR = 0.77, 95%CI:0.70-0.85; 12-month mortality: RR = 0.80, 95%CI:0.77-0.84). Wait times decreased in 2020.

CONCLUSIONS

TTS increased between 2004 and 2019, with NAC affected more. However, despite longer wait times, short-term survival increased significantly. Very short (<15 days) and very long (>75 days) TTS were associated with increased mortality risk. Patients with HPV + HNSCC have the highest increase among those treated > 75 days from diagnosis. Treatment at AC was associated with improved survival, which could be explained by the presence of multidisciplinary teams and subspecialists that may be less available at NAC. The 2021 NCDB data are required for a comprehensive analysis of wait times in 2020.

Clinical insights into small cell lung cancer: Tumor heterogeneity, diagnosis, therapy, and future directions

Small cell lung cancer (SCLC) is characterized by rapid growth and high metastatic capacity. It has strong epidemiologic and biologic links to tobacco carcinogens. Although the majority of SCLCs exhibit neuroendocrine features, an important subset of tumors lacks these properties. Genomic profiling of SCLC reveals genetic instability, almost universal inactivation of the tumor suppressor genes TP53 and RB1, and a high mutation burden. Because of early metastasis, only a small fraction of patients are amenable to curative-intent lung resection, and these individuals require adjuvant platinum-etoposide chemotherapy. Therefore, the vast majority of patients are currently being treated with chemoradiation with or without immunotherapy. In patients with disease confined to the chest, standard therapy includes thoracic radiotherapy and concurrent platinum-etoposide chemotherapy. Patients with metastatic (extensive-stage) disease are treated with a combination of platinum-etoposide chemotherapy plus immunotherapy with an anti-programmed death-ligand 1 monoclonal antibody. Although SCLC is initially very responsive to platinum-based chemotherapy, these responses are transient because of the development of drug resistance. In recent years, the authors have witnessed an accelerating pace of biologic insights into the disease, leading to the redefinition of the SCLC classification scheme. This emerging knowledge of SCLC molecular subtypes has the potential to define unique therapeutic vulnerabilities. Synthesizing these new discoveries with the current knowledge of SCLC biology and clinical management may lead to unprecedented advances in SCLC patient care. Here, the authors present an overview of multimodal clinical approaches in SCLC, with a special focus on illuminating how recent advancements in SCLC research could accelerate clinical development.

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.

Observational Study of the Natural Growth History of Peripheral Small-Cell Lung Cancer on CT Imaging

BACKGROUND

This study aimed to investigate the natural growth history of peripheral small-cell lung cancer (SCLC) using CT imaging.

METHODS

A retrospective study was conducted on 27 patients with peripheral SCLC who underwent at least two CT scans. Two methods were used: Method 1 involved direct measurement of nodule dimensions using a calliper, while Method 2 involved tumour lesion segmentation and voxel volume calculation using the "py-radiomics" package in Python. Agreement between the two methods was assessed using the intraclass correlation coefficient (ICC). Volume doubling time (VDT) and growth rate (GR) were used as evaluation indices for SCLC growth, and growth distribution based on GR and volume measurements were depicted. We collected potential factors related to imaging VDT and performed a differential analysis. Patients were classified into slow-growing and fast-growing groups based on a VDT cut-off point of 60 days, and univariate analysis was used to identify factors influencing VDT.

RESULTS

Median VDT calculated by the two methods were 61 days and 71 days, respectively, with strong agreement. All patients had continuously growing tumours, and none had tumours that decreased in size or remained unchanged. Eight patients showed possible growth patterns, with six possibly exhibiting exponential growth and two possibly showing Gompertzian growth. Tumours deeper in the lung grew faster than those adjacent to the pleura.

CONCLUSIONS

Peripheral SCLC tumours grow rapidly and continuously without periods of nongrowth or regression. Tumours located deeper in the lung tend to grow faster, but further research is needed to confirm this finding.

Acquired Cross-resistance in Small Cell Lung Cancer due to Extrachromosomal DNA Amplification of MYC paralogs

Small cell lung cancer (SCLC) presents as a highly chemosensitive malignancy but acquires cross-resistance after relapse. This transformation is nearly inevitable in patients but has been difficult to capture in laboratory models. Here we present a pre-clinical system that recapitulates acquired cross-resistance in SCLC, developed from 51 patient-derived xenografts (PDXs). Each model was tested for in vivo sensitivity to three clinical regimens: cisplatin plus etoposide, olaparib plus temozolomide, and topotecan. These functional profiles captured hallmark clinical features, such as the emergence of treatment-refractory disease after early relapse. Serially derived PDX models from the same patient revealed that cross-resistance was acquired through a MYC amplification on extrachromosomal DNA (ecDNA). Genomic and transcriptional profiles of the full PDX panel revealed that this was not unique to one patient, as MYC paralog amplifications on ecDNAs were recurrent among cross-resistant models derived from patients after relapse. We conclude that ecDNAs with MYC paralogs are recurrent drivers of cross-resistance in SCLC.

SIGNIFICANCE

SCLC is initially chemosensitive, but acquired cross-resistance renders this disease refractory to further treatment and ultimately fatal. The genomic drivers of this transformation are unknown. We use a population of PDX models to discover that amplifications of MYC paralogs on ecDNA are recurrent drivers of acquired cross-resistance in SCLC.

High risk lung nodule: A multidisciplinary approach to diagnosis and management

Pulmonary nodules are often discovered incidentally during CT scans performed for other reasons. While the vast majority of nodules are benign, a small percentage may represent early-stage lung cancer with the potential for curative treatments. With the growing use of CT for both clinical purposes and lung cancer screening, the number of pulmonary nodules detected is expected to increase substantially. Despite well-established guidelines, many nodules do not receive proper evaluation due to a variety of factors, including inadequate coordination of care and financial and social barriers. To address this quality gap, novel approaches such as multidisciplinary nodule clinics and multidisciplinary boards may be necessary. As pulmonary nodules may indicate early-stage lung cancer, it is crucial to adopt a risk-stratified approach to identify potential lung cancers at an early stage, while minimizing the risk of harm and expense associated with over investigation of low-risk nodules. This article, authored by multiple specialists involved in nodule management, delves into the diagnostic approach to lung nodules. It covers the process of determining whether a patient requires tissue sampling or continued surveillance. Additionally, the article provides an in-depth examination of the various biopsy and therapeutic options available for malignant lung nodules. The article also emphasizes the significance of early detection in reducing lung cancer mortality, especially among high-risk populations. Furthermore, it addresses the creation of a comprehensive lung nodule program, which involves smoking cessation, lung cancer screening, and systematic evaluation and follow-up of both incidental and screen-detected nodules.

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.

Resected cytokeratin-negative small cell lung carcinoma

Small cell lung carcinoma (SCLC), a malignancy of neuroendocrine origin, can show varied morphologies and patterns but is typically positive for at least one neuroendocrine marker and almost always for cytokeratins. It is essential to distinguish this tumour due to its characteristic genetic features, aggressive behaviour, propensity for metastasis and responsiveness to chemotherapy. We hereby present a rare case of a pulmonary mass that showed morphological features of an SCLC but lacked cytokeratin expression on biopsy as well as resection specimens. Various cytokeratins were tested on multiple blocks and at different laboratories. A broad differential diagnosis was considered and ruled out including small round blue cell tumours, non-SCLC and metastasis. After performing an extensive work-up to identify the origin of this tumour, it was finally diagnosed as SCLC with expression of neuroendocrine markers synaptophysin and CD56, and intracytoplasmic electron dense neurosecretory granules (250-350 nm) however lacked cytokeratin expression.

The Surgical Management of Lung Neuroendocrine Neoplasms

This review summarizes key recent developments relevant to the surgical management of lung neuroendocrine neoplasms (L-NENs), including typical and atypical carcinoids, large cell neuroendocrine carcinoma, and small cell lung carcinoma. This review includes recent insights into the classification, clinical presentation, diagnostic workup, treatment options, and follow-up. Highlighted topics include general principles of surgery in localized or locally advanced or metastatic L-NENs, lung-sparing surgery for small, peripheral typical carcinoids, adjuvant and systemic therapies for typical and atypical carcinoids, and surgery and adjuvant therapies for large cell neuroendocrine carcinoma and small cell lung carcinoma.

The Role of Adjuvant Therapy Following Surgical Resection of Small Cell Lung Cancer: A Multi-Center Study

PURPOSE

This multi-center, retrospective study was conducted to evaluate the long-term survival in patients who underwent surgical resection for small cell lung cancer (SCLC) and to identify the benefit of adjuvant therapy following surgery.

MATERIALS AND METHODS

The data of 213 patients who underwent surgical resection for SCLC at four institutions were retrospectively reviewed. Patients who received neoadjuvant therapy or an incomplete resection were excluded.

RESULTS

The mean patient age was 65.29±8.93 years, and 184 patients (86.4%) were male. Lobectomies and pneumonectomies were performed in 173 patients (81.2%), and 198 (93%) underwent systematic mediastinal lymph node dissections. Overall, 170 patients (79.8%) underwent adjuvant chemotherapy, 42 (19.7%) underwent radiotherapy to the mediastinum, and 23 (10.8%) underwent prophylactic cranial irradiation. The median follow-up period was 31.08 months (interquartile range, 13.79 to 64.52 months). The 5-year overall survival (OS) and disease-free survival were 53.4% and 46.9%, respectively. The 5-year OS significantly improved after adjuvant chemotherapy in all patients (57.4% vs. 40.3%, p=0.007), and the survival benefit of adjuvant chemotherapy was significant in patients with negative node pathology (70.8% vs. 39.7%, p=0.004). Adjuvant radiotherapy did not affect the 5-year OS (54.6% vs. 48.5%, p=0.458). Age (hazard ratio [HR], 1.032; p=0.017), node metastasis (HR, 2.190; p < 0.001), and adjuvant chemotherapy (HR, 0.558; p=0.019) were associated with OS.

CONCLUSION

Adjuvant chemotherapy after surgical resection in patients with SCLC improved the OS, though adjuvant radiotherapy to the mediastinum did not improve the survival or decrease the locoregional recurrence rate.

Pathological Stage N1 Limited-Stage Small-Cell Lung Cancer Patients Can Benefit From Surgical Resection

PURPOSE

Surgery is controversial in limited-stage small-cell lung cancer (LS-SCLC) (except for T1-2, N0M0). This study aimed to analyze the survival of LS-SCLC patients with proximal lobe (N1) lymph node metastases after surgery and appropriate postoperative adjuvant treatment.

PATIENTS AND METHODS

We reviewed and followed up medical history and survival data of LS-SCLC patients from June 2007 to June 2016, and a total of 68 pathological stage N1 (p-N1) patients who underwent surgical resection and 71 clinical-stage N1 (c-N1) patients who received chemoradiotherapy were included in the final analysis.

RESULTS

The median follow-up of all the patients was 99.30 months. The median disease-free survival (DFS) of the surgery group was 13.567 months, and the median overall survival (OS) of the surgery and chemoradiotherapy groups were 29.600 months and 21.133 months (P-value < .001), respectively. The 2- and 5-year survival rates of the surgery group were 55.9% and 33.7%, and the 2- and 5-year survival rates of the chemoradiotherapy group were 39.8% and 9.4%, respectively. Meanwhile, postoperative thoracic radiotherapy appeared to be associated with a good prognosis (median OS 36.400 vs. 21.333 months, P-value .048), as did prophylactic cranial irradiation (median OS 50.867 vs. 22.600 months, P-value .007) in the surgery group.

CONCLUSIONS

Surgery may benefit patients with p-N1 SCLC, and in combination with appropriate postoperative adjuvant treatment, surgery may be a new therapeutic modality for SCLC.

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.

Long-term results of postoperative unsuspected small cell lung cancer on real-world data

BACKGROUND

In traditional opinion, solid pulmonary nodule suspected lung cancer should be confirmed by pathology before the operation to exclude small cell lung cancer (SCLC), considering SCLC tends to be aggressive and surgical effect in the management of SCLC remains controversial. The aim of this study was to evaluate the survival result and risk factors of postoperative unsuspected SCLC.

METHODS

A total of 120 patients with postoperative unsuspected SCLC who were confirmed by pathology and referred to Chinese PLA General Hospital between 2000 and 2021 were retrospectively analyzed (surgery group). Additionally, 120 patients with limited-stage SCLC who underwent chemotherapy and radiotherapy in the same period were enrolled in the chemoradiotherapy group.. Kaplan-Meier method was used to estimate survival; the Log-Rank test was used to compare survival rates between different groups; a COX stepwise regression model was used for multivariate analysis.

RESULTS

Among 120 patients in the surgery group, 28 were with central type and other 92 with peripheral type. The median survival (OS) was 44.85 months, and the 5-year survival rate was 46%. The 5-year survival rates for stage I, II, and III were 52.1%, 45.4%, and 27.8%, respectively. The mean disease-free survival time (DFS) was 30.63 ± 4.38 months, and the 5-year DFS rate was 31.5%. In the chemoradiotherapy group, the mean OS was 21.4 ± 4.26 months, and the 5-year survival rate was 28.3%. The 5-year survival rates for clinical stage I, II, and III were 42.5%, 39.8%, and 20.5%, respectively. The mean progression-free survival (PFS) was 10.63 ± 3.6 months. In the surgery group, one-way ANOVA revealed that the gender, symptoms, smoking history, tumor location, and postoperative radiotherapy were not associated with OS (P ≥ 0.05), while age, surgical approach, surgical method, N stage, TNM stage, and vascular tumor thrombus were related to OS (P < 0.05). Multivariate analysis indicated that the N stage was associated with OS (HR = 1.86 P = 0.042).

CONCLUSION

Surgery and adjuvant therapy were found to have encouraging outcomes in postoperative unsuspected SCLC. Patients with stage I, stage II and part of stage IIIA SCLC could benefit from surgery and the standard lobectomy, and systematic lymph node dissection, is also recommended for these patients.

Clinical and prognostic implications of CD47 and PD-L1 expression in surgically resected small-cell lung cancer

BACKGROUND

Pharmacological inhibition of the immune-checkpoint molecule CD47 has shown promising results in preclinical small-cell lung cancer (SCLC) models, whereas anti-programmed death-ligand 1 (PD-L1) inhibitors have been recently implemented in the standard of care of advanced-stage SCLC patients. Nevertheless, the expression pattern, clinical relevance and prognostic implication of both CD47 and PD-L1 are rather controversial in surgically treated SCLC patients.

MATERIALS AND METHODS

In total, 104 Caucasian SCLC patients from two Central European thoracic centers were included in this study. CD47 and PD-L1 expression as well as the expression of the four major SCLC molecular subtype markers (ASCL1, NEUROD1, YAP1 and POU2F3) were measured by immunohistochemistry. Expression levels were independently evaluated and statistically correlated with clinicopathological data and survival.

RESULTS

Positive CD47 and PD-L1 expressions were seen in 84.6% and 9.6% of the samples, respectively. Meanwhile, the tumor-associated stroma was positive for PD-L1 in 59.6% of the cases. Stromal PD-L1 expression correlated with longer overall survival (OS) (versus PD-L1-negative stroma; median OS was 42 versus 14 months, respectively, P = 0.003) and was confirmed as an independent predictor of favorable outcome upon multivariate analysis (hazard ratio 0.530, 95% confidence interval 0.298-0.943, P = 0.031). Notably, neither CD47 nor PD-L1 presence was related to a distinct molecular SCLC subtype.

CONCLUSION

CD47 shows a remarkably high expression while tumoral PD-L1 expression is generally low in surgically treated SCLC. Importantly, stromal PD-L1 expression may indicate a favorable clinical outcome and serve as a novel prognostic factor in these patients. Additional studies are warranted to further investigate the clinical impact of CD47 and PD-L1 expression in SCLC.

Efficacy evaluation of surgery combined with chemotherapy for stage IIIA small cell lung cancer patients: a retrospective analysis

Background

The efficacy of surgery in combination of chemotherapy for stage IIIA small cell lung cancer (IIIA-SCLC) is controversial. The aim of the present study was to analyze the efficacy of surgery combined with chemotherapy, especially in the setting of neoadjuvant chemotherapy (NAC) followed by surgery for IIIA-SCLC.

Methods

Between 2004 and 2015, we reviewed 2,199 chemotherapy-treated stage IIIA (N1/2) SCLC cases in the Surveillance, Epidemiology, and End Results (SEER) database, and 32 NAC + intentional radical resection-treated, centrally-located IIIA-SCLC cases at Shanghai Pulmonary Hospital (SPH). Outcomes were compared between surgically and non-surgically treated patients from the SEER database after propensity score matching (PSM), and comparing lobectomy/bi-lobectomy and pneumonectomy patients from SPH. Prognostic factors were evaluated by Kaplan-Meier method and the Cox proportional hazards regression model.

Results

There was significantly higher overall survival (OS) in surgically treated IIIA-SCLC patients (OS, 44.8 vs. 21.2 months, P=0.048), and similar efficacy was observed between sub-lobectomy and lobectomy/bi-lobectomy patients (OS: 55.6 vs. 30.3 months, P=0.167) in SEER database. At SPH, significantly higher OS was associated with T1 stage (before NAC: T1 vs. T2-4, 48.7 vs. 32.2 months, P=0.025; after NAC: T1 vs. T2-4, 42.7 vs. 21.3 months, P=0.048). Female sex [hazard ratio (HR): 0.078, P=0.009], T1 stage (HR: 13.048, P=0.026), and pneumonectomy (HR: 0.095, P=0.009) were independent prognostic factors for IIIA-SCLC patients who received NAC + intentional radical resection.

Conclusions

For stage IIIA SCLC patients, complete resection combined with chemotherapy might improve the prognosis than patients without surgery. Post-NAC lobectomy was not found to be superior to sub-lobectomy, while pneumonectomy was considered suitable for central-type IIIA-SCLC patients after NAC treatment.

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.

Impact of Lymph Node Dissection on Survival and Tumor Recurrence for Patients with Resected cT1-2N0 Small Cell Lung Cancer

BACKGROUND

The role of lymph node (LN) dissection for early-stage small cell lung cancer (SCLC) remains unclear. Therefore, this study aimed to investigate the impact of LN dissection on patient survival and tumor recurrence for patients with cT1-2N0M0 SCLC.

METHODS

Patients with cT1-2N0M0 SCLC who underwent intent-to-cure surgery at our institution between 2011 and 2019 were retrospectively reviewed. The survival outcomes of patients with systematic LN dissection (n = 112) and LN sampling (n = 35) were compared before and after propensity score-matching (PSM), as were the outcomes for patients with (pN+) and without (pN0) pathologic nodal metastasis. The prognostic impact of LN dissection was evaluated through multivariable analysis.

RESULTS

The dissection group displayed significantly better overall survival (66.4% vs. 48.4%; P = 0.009) and recurrence-free survival (RFS) (63.5% vs. 37.6%;, P = 0.003) than the sampling group at 5 years. The rate of local recurrence was significantly lower in the dissection group than in the sampling group (11.6% vs. 42.9%; P < 0.001). After adjustment by multivariable analysis and PSM, LN dissection retained its independent favorable effects. The overall nodal upstaging rate was 37.6%, and the dissection group had a tendency of better RFS in both the pN0 (P = 0.05) and pN+ (P = 0.036) patients.

CONCLUSION

Systematic LN dissection is associated with improved survival of patients who undergo surgery for cT1-2N0 SCLC. Further studies are warranted to verify the necessity of LN dissection in the surgery for SCLC.

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.

The Role of Surgery in High-Grade Neuroendocrine Cancer: Indications for Clinical Practice

Pulmonary neuroendocrine tumors (pNET) represent a particular type of malignant lung cancers and can be divided into well-differentiated low-grade NET and poorly-differentiated high-grade NET. Typical and atypical carcinoids belong to the first group while large cell neuroendocrine carcinomas (LCNEC) and small-cell lung cancers (SCLC) belong to the second one. The aim of this mini-review is to focus on the role of surgical therapy for high grade neuroendocrine tumors. SCLC has the worst prognosis among all lung cancer neoplasms: in fact, the two-year survival rate is about 5% and median survival usually ranges between 15 and 20 months. The surgical treatment of SCLC has thus infrequently been judged as a valuable aspect of the therapeutic approach, the gold standard treatment being a combination of platinum-based chemotherapy and radiotherapy. As LCNEC are rare, there is a lack of extensive literature and randomized clinical trials, therefore the curative approach is still controversial. Current treatment guidelines suggest treating LCNEC by surgical resection in non-metastatic stages and recommend adjuvant chemotherapy according to SCLC protocol. Upfront surgery is suggested in early stages (from I to IIB), a multimodality approach is recommended in locally advanced stages (III) while surgery is not recommended in stage IV LCNEC. The rate of surgical resection is quite low, particularly for SCLC, ranging from 1 to 6% in limited diseases; lobectomy with radical lymphadenectomy is considered the gold standard surgical procedure in the case of limited disease SCLC and resectable LCNEC; pneumonectomy, although reported as an effective tool, should be avoided in the light of local and distant recurrence rates.

Large Cell Neuroendocrine Carcinoma of the Lung: Current Understanding and Challenges

Large cell neuroendocrine carcinoma of the lung (LCNEC) is a rare and highly aggressive type of lung cancer, with a complex biology that shares similarities with both small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC). The prognosis of LCNEC is poor, with a median overall survival of 8-12 months. The diagnosis of LCNEC requires the identification of neuroendocrine morphology and the expression of at least one of the neuroendocrine markers (chromogranin A, synaptophysin or CD56). In the last few years, the introduction of next-generation sequencing allowed the identification of molecular subtypes of LCNEC, with prognostic and potential therapeutic implications: one subtype is similar to SCLC (SCLC-like), while the other is similar to NSCLC (NSCLC-like). Because of LCNEC rarity, most evidence comes from small retrospective studies and treatment strategies that are extrapolated from those adopted in patients with SCLC and NSCLC. Nevertheless, limited but promising data about targeted therapies and immune checkpoint inhibitors in patients with LCNEC are emerging. LCNEC clinical management is still controversial and standardized treatment strategies are currently lacking. The aim of this manuscript is to review clinical and molecular data about LCNEC to better understand the optimal management and the potential prognostic and therapeutic implications of molecular subtypes.

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.

The overall survival impact of prophylactic cranial irradiation in limited-stage small-cell lung cancer: a systematic review and meta-analysis

•

PCI for LS-SCLC patients has become more controversial.

•

Literature search on PCI impact on overall survival in LS-SCLC yielded 28 studies.

•

Meta-analysis of adjusted HRs revealed pooled HR of 0.62 (95% CI: 0.57–0.69).

•

Findings support PCI in current practice while awaiting prospective trial results.

Background

Prophylactic cranial irradiation (PCI) for limited-stage small-cell lung cancer (LS-SCLC) patients has become more controversial. Since the publication of the systematic review by Aupérin et al. in 1999, no randomized controlled trials regarding PCI in LS-SCLC have been completed. The aim of this study was to systematically review and meta-analyze the effect of PCI on overall survival (OS) in patients with LS-SCLC.

Methods

A systematic search was conducted in the databases of MEDLINE (PubMed), Embase and the Cochrane library. Only studies that reported an adjusted hazard ratio (aHR), indicating the effect of PCI versus no PCI on OS (adjusted for confounders) in patients with LS-SCLC were included for critical appraisal and meta-analysis. A pooled aHR estimate was calculated using a random-effects model.

Results

Pooling of 28 retrospective studies including a total of 18,575 patients demonstrated a significant beneficial effect of PCI versus no PCI on OS with a pooled aHR of 0.62 (95% CI: 0.57–0.69). Substantial heterogeneity of reported aHRs among studies was observed (I² = 65.9%). Subgroup analyses revealed that this heterogeneity could partly be explained by study sample size. The pooled aHR among 7 versus 21 studies with a sample size of > 300 versus ≤ 300 patients was 0.79 (95% CI: 0.64–0.97) versus 0.56 (95% CI: 0.46–0.69; p < 0.001), respectively.

Conclusions

This meta-analysis demonstrates a significant beneficial effect of PCI on OS in patients with LS-SCLC. Larger studies reported a milder beneficial effect, possibly due to a decreased risk of model overfitting. Serious risk of selection and confounding bias were of concern due to the lack of prospective trials. These results support the role of PCI in standard clinical practice in patients with LS-SCLC while awaiting results of prospective trials on alternative strategies.

Downregulation of REV-ERBα is associated with the progression of lung adenocarcinoma

Background

The nuclear receptor REV-ERBα (nuclear receptor subfamily 1, Group D member 1, NR1D1) is one of the essential components of the circadian clock which modulates cell proliferation, glucose metabolism, inflammation, and many other biological processes. Modulation of these processes are also relevant to cancer development. Previous studies have suggested that activation of REV-ERBα correlates with cancer cell senescence and death, but how REV-ERBα play roles in tumor progression require further elucidation.

Methods

We investigated the expression of REV-ERBα in clinical samples by immunohistochemistry (IHC). REV-ERBα is downregulated by shorth hairpin RNA (shRNA). The gene expression level of each group was detected by Western blot analysis. The effects of REV-ERBα downregulation on apoptosis and cell cycles was assessed by flow cytometry assay. A549 cell growth curve under different treatments measured by MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] assay. Cell invasion ability under different treatments was measured by Transwell assay. Immunostaining analysis was also used for evaluating the effects of downregulation of REV-ERBα on nuclear factor-κB (NF-κB).

Results

Compared to 81.8% (54/66) of samples exhibiting a lower expression level of REV-ERBα in cancer tissue than in paired normal tissue, only 18.2% (12/66) were higher or equally expressed in lung cancer tissue. Furthermore, downregulation of REV-ERBα by RNA interference can significantly enhance the transcription of nuclear factor-κB (NF-κB), while the expression of p53 remained the same. Downregulation of REV-ERBα was also shown to stimulate the invasion and promote the proliferation of lung adenocarcinoma cell line A549.

Conclusions

Our findings suggest that tumorigenesis and progression of lung carcinoma is relevant to downregulation or inhibition of REV-ERBα. This pathophysiological process also correlates with regulation of the NF-κB signaling pathway, indicating that REV-ERBα is a potential target of lung cancer therapy.

Surgical Principles in the Management of Lung Neuroendocrine Tumors: Open Questions and Controversial Technical Issues

OPINION STATEMENT

Primary neuroendocrine tumors (NETs) of the lung represent a heterogeneous group of malignancies arising from the endocrine cells, involving different entities, from well differentiated to highly undifferentiated neoplasms. Because of the predominance of poorly differentiated tumors, advanced disease is observed at diagnosis in more than one third of patients making chemo- or chemoradiotherapy the only possible treatment. Complete surgical resection, as defined as anatomical resection plus systematic lymphadenectomy, becomes a reliable curative option only for that little percentage of patients presenting with stage I (N0) high-grade NETs. On the other hand, complete surgical resection is considered the mainstay treatment for localized low- and intermediate-grade NETs. Therefore, in the era of the mini-invasive surgery, their indolent behavior has suggested that parenchyma-sparing resections could be as adequate as the anatomical ones in terms of oncological outcomes, leading to discuss about the correct extent of resection and about the role of lymphadenectomy when dealing with highly differentiated NETs.

Prophylactic cranial irradiation (PCI), hippocampal avoidance (HA) whole brain radiotherapy (WBRT) and stereotactic radiosurgery (SRS) in small cell lung cancer (SCLC): Where do we stand?

Small cell lung cancer (SCLC) is an aggressive form of lung cancer associated with an increased risk of develping brain metastases (BM), which are a significant cause of morbidity and mortality. Prophylactic cranial irradiation (PCI) was first introduced in the 1970s with the aim of reducing BM incidence and improving survival and quality of life (QoL). Prospective clinical trials and meta-analyses have demonstrated its effectiveness in reducing BM incidence and improving survival, across all stages of the disease following response to induction chemotherapy. Despite its long history, "unknowns" surrounding PCI use still exist and there are particular subgroups of patients for which its use remains controversial. PCI is known to cause neurocognitive toxicity which can have a significant impact on a patient's QoL. Strategies to minimise this, including the use of hippocampal avoidance radiotherapy techniques, neuroprotective drugs and stereotactic radiosurgery in place of whole brain radiotherapy for the treatment of BM, are under evaluation. This review offers a summary of the key PCI trials published to date and the current treatment recommendations based on available evidence. It also discusses the key questions being addressed in ongoing clinical trials and highlights others where there is currently a knowledge gap and therefore where further data are urgently required.

Impact of Adjuvant Therapy on Survival in Surgically Resected Limited-Stage Small Cell Lung Cancer

Background

Data on efficacy of adjuvant therapy for surgically resected small cell lung cancer are scant. This study was determined to reveal the survival benefits of different adjuvant treatment modalities for limited-stage small cell lung cancer patients following surgical resection.

Methods

Data of patients with histologically confirmed small cell lung cancer after surgical resection were collected from November 2006 to June 2019. Survival analyses were calculated by Kaplan–Meier method, with log-rank test to evaluate statistical significance. Prognostic factors were identified by multivariate analysis using cox proportional hazards model. Further survival analysis and cox regression analysis stratified by clinicopathologic features were conducted to evaluate the survival benefits of different adjuvant treatment modalities.

Results

In total, 153 out of 157 patients were analyzed. Multivariate analysis showed male sex, lymph node metastasis, residual tumor, VPI and non-adjuvant therapy were independently associated with poor prognosis. Subgroup analyses revealed both adjuvant chemotherapy and adjuvant chemoradiotherapy were significantly associated with superior survival for stage pT2-4 (HR=0.176, 95%CI:0.053-0.578, p=0.004; and HR=0.115, 95%CI:0.033-0.405, p=0.001) and pure SCLC patients (HR=0.182, 95%CI:0.067-0.494, p=0.001; and HR=0.181, 95%CI:0.071-0.465, p<0.001). For pN0 patients, adjuvant chemotherapy was associated with better survival (HR=0.219, 95%CI:0.054-0.891, p=0.034), while adjuvant chemoradiotherapy was associated with improved survival for pN+ patients (HR=0.324, 95%CI:0.138-0.760, p=0.010).

Conclusions

For patients without pathologic lymph node metastasis, there is a survival benefit with adjuvant chemotherapy. However, for patients with pathologic lymph node metastasis, adjuvant chemoradiotherapy might achieve a significant survival benefit. Further prospective studies are needed to validate the results.

Octogenarians may benefit from stage-specific small cell lung cancer treatment

BACKGROUND

Our study investigates treatment profiles in octogenarian patients with small cell lung cancer (SCLC) and assesses each treatment's role in a stage-specific manner.

METHODS

Patient data from individuals with SCLC aged 80 years and older between 1988 and 2015 in the Surveillance, Epidemiology, and End Results Program (SEER) database were extracted. Cancer-specific survival (CSS) between patients with no treatment and different treatment groups were compared by the Kaplan-Meier method, with stratifications by stage. Cox Proportional Hazard model further identified independent prognostic factors.

RESULTS

A total of 7,290 patients were included in this study. Notably, 3,358 (46.1%) patients did not receive active treatment. Compared with the no active treatment group, the CSS of patients who received treatment was significantly improved (median 6 vs. 0 months, P<0.001) and further validated in stage subgroups. Chemotherapy combined with local therapy was associated with the best CSS in regional and distant disease stages, with the hazard ratios (HR) and 95% confidence intervals (CI) being 0.30 (0.26-0.34) and 0.27 (0.25-0.30), respectively. Local therapy only appeared to confer better oncological outcomes (HR =0.33; 95% CI: 0.25-0.42) than chemotherapy only (HR =0.37; 95% CI: 0.29-0.47) in the localized disease stage.

CONCLUSIONS

Although nearly half of octogenarians with SCLC did not receive active treatment in the real clinical setting, these patients may benefit from treatment. Chemotherapy combined with local therapy may provide the best treatment choice in octogenarians with advanced SCLC, while local therapy appears to play a more critical role in treating those with early-stage disease.

Effectiveness and safety of bevacizumab in extensive-disease small cell lung cancer: a systemic review and meta-analysis

Background

Small cell lung cancer (SCLC) is highly invasive and poorly prognostic. The effects of chemotherapy with bevacizumab are promising on other tumors but unclear in extensive-disease SCLC (ED-SCLC). A systemic review and meta-analysis were performed to investigate the efficacy and toxicity in ED-SCLC patients.

Methods

A review of current studies was performed on electronic databases and other sources to identify publications of ED-SCLC patients who received bevacizumab. Endpoints included overall survival (OS), progression-free survival (PFS), objective response rate (ORR), disease control rate (DCR), and complications.

Results

Nine relevant articles with six single-arm and three two-arm studies were identified. Four hundred seventy-six patients were included, of which 368 and 108 were untreated and relapse patients. Most patients were performance status 0–1 (71.6%) and male (58.1%). The comparisons showed CT/bevacizumab slightly prolonged OS (HR =0.84) but significantly improved PFS (HR =0.74). The ORRs of untreated and relapse patients were 71% and 19%, though no significant difference was observed than CT/placebo. The most grade 3–4 complication and bevacizumab-associated complications were neutropenia and hypertension, whose rates were 33% and 6%. Patients who received CT/bevacizumab had a higher hypertension rate than CT/placebo (6% vs. 2%). No different complication rate was observed between high and lose dose groups.

Discussion

The present study suggests that bevacizumab in the combination of standard chemotherapy provides better PFS than chemotherapy alone. Although the combined regimen is well-tolerated, no superiority in OS or response rate is observed.

Effect of surgery on survival in patients with stage III N2 small cell lung cancer: propensity score matching analysis and nomogram development and validation

Background

The standard treatment of stage III N2 small cell lung cancer (SCLC) is concurrent chemoradiation, and surgery is not recommended. This study was aimed to evaluate whether surgery has survival benefits in patients with stage III N2 SCLC and investigate the factors influencing survival of surgery.

Methods

Patients diagnosed with stage T1-4N2M0 SCLC from 2004 to 2015 were selected from the Surveillance Epidemiology End Results database. Propensity score matching (PSM) was used to balance confounders between patients who underwent surgery and those treated with radiation and/or chemotherapy. We compared overall survival (OS) of the two groups using Kaplan-Meier curves and a Cox proportional hazard model. We also identified prognostic factors in patients with surgical resection, and a nomogram was developed and validated for predicting postoperative OS.

Results

−A total of 5576 patients were included in the analysis; of these, 211 patients underwent surgery. PSM balanced the differences between the two groups. The median OS was longer in the surgery group than in the non-surgery group (20 vs. 15 months; p = 0.0024). Surgery was an independent prognostic factor for longer OS in the multivariate Cox regression analysis, and subgroup analysis revealed a higher survival rate in T1 stage patients treated with surgery (hazard ratio = 0.565, 95% confidence interval: 0.401–0.798; p = 0.001). In patients who underwent surgery, four prognostic factors, including age, T stage, number of positive lymph nodes, and radiation, were selected into nomogram development for predicting postoperative OS. C-index, decision curve analyses, integrated discrimination improvement, and time-dependent receiver operating characteristics showed better performance in nomogram than in the tumor-node-metastasis staging system. Calibration plots demonstrated good consistency between nomogram predicted survival and actual observed survival. The patients were stratified into three different risk groups by prognostic scores and Kaplan-Meier curves showed significant difference between these groups.

Conclusions

These results indicate that surgery can prolong survival in patients with operable stage III N2 SCLC, particularly those with T1 disease. A nomogram that includes age, T stage, number of positive lymph nodes, and radiation can be used to predict their long-term postoperative survival.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02364-6.

Prognostic factors of patients with small cell lung cancer after surgical treatment

Background

The current National Comprehensive Cancer Network guidelines recommend surgical treatment for patients with stages I–IIA small cell lung cancer (SCLC), but it still cannot deny the effect of surgical treatment on other limited-stage SCLC. Although more advanced diagnostic methods are now used for the diagnosis and classification of SCLC, the selection of surgical candidates is still arbitrary.

Methods

Data were collected from patients with SCLC who underwent surgery at the First Affiliated Hospital of Zhengzhou University from January 2011 to January 2021. Kaplan-Meier method was used to calculate cumulative survival curves, and log-rank test was used to evaluate differences among different subgroups. The Cox proportional hazard regression model was used to assess the predictive power of the variables for prognosis and survival.

Results

Smoking index, surgical resection method, TNM stage of postoperative pathology, and postoperative chemotherapy were significantly correlated with postoperative survival (P<0.05), which were independent predictors for postoperative survival. Patients with a smoking index >800 had a higher risk of death after surgery [hazard ratio (HR): 7.050, 95% confidence interval (CI): 3.079–16.143, P<0.001]. Compared with patients who underwent pulmonary lobectomy, those who underwent other pneumoresections (e.g., wedge resection, segmental resection, sleeve resection) had an increased risk of death (HR: 2.822, 95% CI: 1.030–7.734, P=0.044). Compared with stage I patients, stage II and stage III patients had an increased risk of death, with HRs of 6.039 and 3.145, respectively. Compared with those who received ≤4 courses of postoperative chemotherapy, those who received >4 courses of postoperative chemotherapy had reduced postoperative mortality risk (HR: 0.211, 95% CI: 0.097–0.459, P<0.001).

Conclusions

A high smoking index suggests worse prognosis; therefore, patients who smoke should be advised to quit smoking. Compared with stage II and stage III patients, surgical treatment is recommended for stage I SCLC patients. TNM staging, especially N staging, should be evaluated prior to surgery. Pulmonary lobectomy with mediastinal lymph node dissection should be the preferred surgical treatment for patients with SCLC. Patients should receive at least 5 courses of adjuvant chemotherapy after surgery.

Adjuvant therapy for lung neuroendocrine neoplasms

Pulmonary neuroendocrine neoplasms (NENs) represent a minority of lung cancers and vary from slower growing pulmonary carcinoid (PC) tumors to aggressive small cell lung cancer (SCLC). While SCLC can account for up to 15% of lung cancer, PCs are uncommon and represent about 2% of lung cancers. Surgical resection is the standard of care for early-stage PCs and should also be considered in early stage large cell neuroendocrine carcinoma (LCNEC) and SCLC. Adjuvant treatment is generally accepted for aggressive LCNEC and SCLC, however, less well established for PCs. Guidelines admit a lack of trials to support a high-level recommendation for adjuvant therapy. This manuscript will discuss the role for adjuvant therapy in NENs and review the available literature.

[Surgery for small-cell lung cancer]

Small-cell lung cancer (SCLC) is a high-grade neuroendocrine carcinoma, metastatic at the time of initial diagnosis in 70% of cases. Within the 30% of localised tumours only 5% of patients are eligible for surgical treatment according to the recommendations of learned societies. These recommendations are mainly based on old phase II and III randomised prospective trials and more recent registry studies. Surgical care is only possible within a multimodal treatment and essentially concerns small-sized tumours without involvement of hilar or mediastinal lymph nodes. As with non-small cell lung cancer (NSCLC), lobectomy with radical lymph node removal is the recommended procedure to achieve complete tumour resection. Patient selection for surgery includes age, performance status and comorbidity factors. Adjuvant chemotherapy combining Platinum salts and Etoposide for resected stage I tumours is recommended by ASCO, ACCP and NCCN. The precise sequence of neo-adjuvant or adjuvant treatments remains controversial because of the large heterogeneity in clinical practice reported in the studies and the context at the time of SCLC discovery. The 5-year survival rate of patients with early stage disease (pT1-2N0M0) treated by lobectomy and adjuvant chemotherapy is between 30% and 58%, which validates the primary place that surgery must have in these early forms. There is certainly little or even no place for such a therapeutic sequence in locally advanced stages (T3-T4 or N2). However, the stage heterogeneity, as in NSCLC, makes final conclusions difficult. In fact, some registry studies with pairing scores reported a median survival of more than 20 months in N2 SCLC. So, all files of SCLC must be evaluated in a multidisciplinary meeting in order to find the optimal solution for patients with rare and heterogeneous tumours.

Surgery Plus Chemotherapy Versus Surgery Alone for Limited-Stage Small-Cell Lung Cancer: A Population-Based Survival Outcome Analysis

Introduction

For patients with limited-stage small-cell lung cancer (LS-SCLC), effective treatment methods still remain a clinical challenge. The aim of this study is to evaluate the survival outcome of surgery plus chemotherapy vs. surgery alone in patients with LS-SCLC.

Methods

LS-SCLC patients selected from the Surveillance, Epidemiology and End Results (SEER) database diagnosed between January 1, 2004, and December 31, 2015. Comparison of overall survival (OS) and cancer-specific survival (CSS) between two groups performed propensity score matching (PSM), inverse probability of treatment weight (IPTW), and overlap weighting analysis.

Results

Of the 477 LS-SCLC patients identified from the SEER database between 2004 and 2015, 262 (54.9%) received surgery-plus-chemotherapy treatment and the others received surgery-alone treatment. Univariate and multivariate analyses showed that treatment option (P< 0.001), tumor location (P= 0.02) and AJCC stage (P< 0.001) were independent prognostic predictors of OS in LS-SCLC patients. Median OS was 35 months in surgery-plus-chemotherapy group vs. 23 months in surgery-alone group. Survival analysis showed that surgery plus chemotherapy offered significantly improved OS as compared with surgery-alone treatment before and after IPTW, PSM and overlap weighting method (all P< 0.05). According to AJCC stage stratification, OS of the unmatched patients with stage I (P= 0.049) and II (P= 0.001) SCLC who received surgery-plus-chemotherapy treatment was significantly better than that of surgery-alone patients.

Conclusions

This cohort study showed that surgery plus chemotherapy was associated with longer survival time than surgery alone in LS-SCLC patients, especially in those with stage I and II SCLC. Further prospective studies are required to confirm our conclusions.