Small cell lung cancer: where do we go from here?

Durable response to durvalumab-based immunochemotherapy in small-cell lung carcinoma transformation from EGFR-mutant non-small cell lung cancer: A case report

Combined small‐cell lung carcinoma (C‐SCLC) is small‐cell lung carcinoma (SCLC) with added non–small‐cell morphology. We report a case of epidermal growth factor receptor (EGFR) mutation‐positive C‐SCLC in an 84‐year‐old patient with metastatic brain lesions who developed intrinsic resistance to osimertinib, a tyrosine kinase inhibitor (TKI). The patient was diagnosed with small‐cell transformation of non–small‐cell lung carcinoma (NSCLC) and received 6 cycles of dose‐adjusted durvalumab with etoposide and carboplatin. In December 2021, the patient received the seventeenth cycle of maintenance durvalumab 19 months after diagnosis and showed continued treatment response and disease control. Comprehensive molecular profiling and repeated biopsies are recommended in NSCLC patients who progress on first‐line EGFR‐TKIs. Durvalumab in combination with chemotherapy appears to be beneficial for EGFR mutation‐positive C‐SCLC patients that are resistant to TKIs.

First-Line Treatments for Extensive-Stage Small-Cell Lung Cancer With Immune Checkpoint Inhibitors Plus Chemotherapy: A Network Meta-Analysis and Cost-Effectiveness Analysis

Background

Immune checkpoint inhibitors (ICIs) plus chemotherapy were unlikely to be considered cost-effective compared with chemotherapy as the first-line treatment of patients with extensive-stage small-cell lung cancer (ES-SCLC) in China due to its high costs. However, the cost-effectiveness of the comparison between the regimens of ICIs plus chemotherapy were remained unclear yet. The aim of this study was to evaluate the efficacy and cost-effectiveness of ICIs plus chemotherapy as the first-line treatment for ES-SCLC from the perspective of the Chinese healthcare system.

Methods

A network meta-analysis (NMA) was conducted to indirect compare the clinical benefits between the ICIs plus chemotherapy regimens. A decision-analytic model was established to evaluate the cost-effectiveness from the Chinese healthcare system, the clinical efficacy and safety data were obtained from the clinical trials and the results of NMA. Cost and utility values were gathered from the local charges and previously studies. Key outputs of the NMA were overall survival (OS) and progression-free survival (PFS). Incremental cost-effectiveness ratios (ICERs) were estimated. One-way and probabilistic sensitivity analyses were performed to explore the robustness of the model outcomes.

Results

Five clinical trials (IMpower133, CASPIAN, KEYNOTE-604, CA184-156, and EA5161) of 1,255 patients received first-line ICIs plus chemotherapy strategies were analyzed in the NMA. NMA showed that nivolumab plus chemotherapy was ranked higher than other strategies. The cost-effectiveness analysis showed that atezolizumab plus chemotherapy achieved relatively higher health benefits and lower costs. One-way sensitivity analyses revealed that the cost of ICIs had the substantial impact on model outcomes. The probabilistic sensitivity analyses suggested that the probability of atezolizumab plus chemotherapy could be considered cost-effective was more than 50% at the willingness-to-pay (WTP) threshold of $31,313/QALY in China. In scenario analyses, when the price of nivolumab reduced 80%, the probability of nivolumab plus chemotherapy being cost-effective was more than 50%.

Conclusions

The NMA and cost-effectiveness revealed that atezolizumab plus chemotherapy is the most favorable first-line treatment for previously untreated ES-SCLC patients compared other ICIs plus chemotherapy regimens in China. The price reduction of nivolumab would make nivolumab plus chemotherapy be the most cost-effective option in future possible context.

In vivo and in vitro inhibition of SCLC by combining dual cancer-specific recombinant adenovirus with Etoposide

PURPOSE

Oncolytic virotherapy is emerging as an important modality in cancer treatment. In a previous study, we designed and constructed Ad-Apoptin-hTERTp-E1a (Ad-VT), a dual cancer-selective anti-tumor recombinant adenovirus.

METHODS

To explore the therapeutic effect of recombinant adenovirus Ad-VT together with Etoposide on small cell lung cancer, the ability of Ad-VT alone, Etoposide alone, and a combination of Ad-VT + Etoposide to inhibit proliferation of NCI-H446 and BEAS-2B cells was investigated using the WST-1 method. According to the inhibitory action of different combinations, a combination index (CI) was estimated by CalcuSyn software to select the best combination. The inhibitory effect of Ad-VT combined with Etoposide on NCI-H446 and BEAS-2B cells was detected by crystal violet staining and the CFST method. Hoechst, Annexin V and JC-1 staining were used to explore the inhibitory pathway of Ad-VT combined with Etoposide on NCI-H446 cells. The migratory and invasive abilities of treated NCI-H446 cells were assessed by Transwell and BioCat methods. Tumor volume, body weight and survival rate were measured to analyze the anti-tumor and toxic effects of different treatments in tumor-bearing mice.

RESULTS

Ad-VT (20 MOI) combined with Etoposide (400 nM) significantly inhibited NCI-H446 cell proliferation with reduced toxicity of Etoposide to normal cells. Ad-VT induced apoptosis of NCI-H446 cells mainly through the mitochondrial apoptosis pathway, an effect significantly increased by the combined treatment. Ad-VT together with Etoposide significantly inhibited migration and invasion of NCI-H446 cells, inhibited tumor growth in vivo and prolonged the survival of tumor-bearing mice.

CONCLUSIONS

The above results indicate that when combined with Etoposide, Ad-VT may have an important role in synergistically inhibiting tumors.

Efficacy and safety of amrubicin monotherapy after atezolizumab plus carboplatin and etoposide in patients with relapsed small-cell lung cancer

This study examined the activity and safety of amrubicin monotherapy among relapsed small-cell lung cancer (SCLC) patients who had previously been treated with atezolizumab plus carboplatin and etoposide (AteCE). This retrospective study evaluated patients with relapsed SCLC who were treated with previously AteCE combination therapy followed by amrubicin monotherapy between August 2019 and May 2021. Clinical efficacy and toxicity were analyzed. Overall, 40 patients were included: 12 and 28 patients had sensitive and refractory relapse, respectively. The response rate was 32.5% (25.0% in the sensitive group and 35.7% in the refractory group). The median progression-free survival (PFS) and overall survival (OS) from the first amrubicin treatment was 3.4 months (95% CI: 1.9-4.9 months) and 9.9 months (95% CI: 4.5-11.5 months), respectively. There was no significant between-group difference in median PFS (3.6 months vs. 3.2 months, p = 0.42) or median OS (11.2 months vs. 7.3 months, p = 0.78). Grade ≥ 3 hematological adverse events occurred as follows: decreased white blood cells in 52.5% of patients; decreased neutrophil count in 57.5%; and febrile neutropenia in 10.0%. Grade 3 pneumonitis was observed in one patient. There were no treatment-related deaths. Amrubicin is feasible and effective for relapsed SCLC patients previously treated with AteCE therapy. Although immune checkpoint inhibitor treatment (ICI) does not improve the effect of amrubicin, the toxicity is not increased, suggesting that amrubicin remains effective even after ICI administration. Thus, amrubicin after AteCE could be the preferred standard chemotherapeutic choice in patients with relapsed SCLC.

Treatment of small cell lung cancer: recent advances

PURPOSE OF REVIEW

In this article, we aimed to summarize the recent progress being made in treatment of small cell lung cancer (SCLC).

RECENT FINDINGS

SCLC is characterized by strong invasiveness, easy recurrence and early metastasis. In recent years, the emergence of immune checkpoint inhibitors (ICIs) therapy has broken the deadlock in the treatment field of SCLC. Combination strategies, such as the addition of ICIs to chemotherapy and radiotherapy, are actively underway. Some of these strategies have yielded significant survival benefits and tolerable adverse events, whereas several of them have failed with no significant improvement. In addition, the new classification of SCLC based on genomic analysis has deepened the understanding of SCLC and suggested new therapeutic directions. Similarly, the discovery of some new therapeutic targets, such as DDL3, CDK7 and PARP, also brings new hope for improving the survival of patients with SCLC.

SUMMARY

In this article, we will review the recent advances of therapeutic regimen for patients with SCLC. Following the revolutionary success of adding ICIs to chemotherapy, more varieties of combination strategies have been explored in recent trials. In addition, therapeutic drug research and efficacy evaluation against for new targets are under investigation. Altogether, progress on genomic analysis, investigation of biological pathways and treatment regimen combination are providing renewed hope for patients with SCLC.

Survival of Black and White Patients With Stage IV Small Cell Lung Cancer

Background

Small cell lung cancer (SCLC) is associated with aggressive biology and limited treatment options, making this disease a historical challenge. The influence of race and socioeconomic status on the survival of stage IV SCLC remains mostly unknown. Our study is designed to investigate the clinical survival outcomes in Black and White patients with stage IV SCLC and study the demographic, socioeconomic, clinical features, and treatment patterns of the disease and their impact on survival in Blacks and Whites.

Methods and Results

Stage IV SCLC cases from the National Cancer Database (NCDB) diagnosed between 2004 and 2014 were obtained. The follow-up endpoint is defined as death or the date of the last contact. Patients were divided into two groups by white and black. Features including demographic, socioeconomic, clinical, treatments and survival outcomes in Blacks and Whites were collected. Mortality hazard ratios of Blacks and Whites stage IV SCLC patients were analyzed. Survival of stage IV SCLC Black and White patients was also analyzed. Adjusted hazard ratios were analyzed by Cox proportional hazards regression models. Patients’ median follow-up time was 8.18 (2.37-15.84) months. Overall survival at 6, 12, 18 and 24 months were 52.4%, 25.7%, 13.2% and 7.9% in Blacks in compared to 51.0%, 23.6%, 11.5% and 6.9% in Whites. White patients had significantly higher socioeconomic status than Black patients. By contrast, Blacks were found associated with younger age at diagnosis, a significantly higher chance of receiving radiation therapy and treatments at an academic/research program. Compared to Whites, Blacks had a 9% decreased risk of death.

Conclusion

Our study demonstrated that Blacks have significant socioeconomic disadvantages compared to Whites. However, despite these unfavorable factors, survival for Blacks was significantly improved compared to Whites after covariable adjustment. This may be due to Blacks with Stage IV SCLC having a higher chance of receiving radiation therapy and treatments at an academic/research program. Identifying and removing the barriers to obtaining treatments at academic/research programs or improving the management in non-academic centers could improve the overall survival of stage IV SCLC.

Progression and metastasis of small cell lung carcinoma: the role of the PI3K/Akt/mTOR pathway and metabolic alterations

Small cell lung carcinoma (SCLC) is characterized by high metastatic rate and poor prognosis. The platinum-based chemotherapy still represents the backbone of the therapy; however, acquired resistance develops almost in all patients. Although SCLC has been formerly considered a homogeneous disease, recent advances in SCLC research have highlighted the importance of inter- and intratumoral heterogeneity and have resulted in the subclassification of SCLC. The newly described SCLC subtypes are characterized by distinct biological behavior and vulnerabilities that can be therapeutically exploited. The PI3K/Akt/mTOR pathway is frequently affected in SCLC, and its activation represents a promising therapeutic target. Since the mTOR pathway is a master regulator of cellular metabolism, its alterations may also influence the bioenergetic processes of SCLC cells. Despite the encouraging preclinical results, both mTOR and metabolic inhibitors have met limited clinical success so far. Patient selection for personalized therapy, the development of rational drug combinations, and a better understanding of heterogeneity and spatiotemporal evolution of the tumor cells may improve efficacy and can help to overcome acquired resistance. Here we provide a summary of current investigations regarding the role of the mTOR pathway and metabolic alterations in the progression and metastasis formation of SCLC.

Immune Checkpoints OX40 and OX40L in Small-Cell Lung Cancer: Predict Prognosis and Modulate Immune Microenvironment

Background

OX40 and OX40 ligand (OX40L), as essential immune checkpoint (IC) modulators, are highly correlated with cancer immunity regulation as well as tumor microenvironment (TME). Immunotherapy showed outstanding advantages in small-cell lung cancer (SCLC) therapy. However, functions and clinical significance of OX40 and OX40L in SCLC were not clear yet.

Materials and Methods

SCLC samples of 143 patients were collected for immunohistochemistry (IHC) or whole-exome sequencing (WES). We comprehensively explored the expression and mutation of OX40/OX40L in SCLC, and systematically linked OX40/OX40L with TME.

Results

The expression of OX40/OX40L on tumor cells and tumor-infiltrating lymphocytes (TILs) was found in the IHC cohort and verified in other cohorts with SCLC tissues and cell lines. The results showed co-expression patterns among OX40/OX40L, other ICs, and T-cell markers. The WES data suggested that OX40/OX40L mutation is rare in SCLC (<5%). Patients with positive OX40 protein expression on TILs showed substantially higher recurrence-free survival than those with negative expression (p=0.009). The external dataset also indicated that high OX40/OX40L expression was correlated with better prognosis [overall survival: OX40, p<0.001; OX40L, p=0.019]. Importantly, activation of immunity and high infiltration of CD4(+) and CD8(+) T cells were observed in the high OX40/OX40L expression group.

Conclusions

Collectively, this work highlighted the significance of OX40 and OX40L in prognosis and TME cell infiltration characterization of SCLC. Evaluating the OX40/OX40L-expression levels of individual patients with SCLC might contribute to guiding more precise therapy.

FK228 potentiates topotecan activity against small cell lung cancer cells via induction of SLFN11

The response rate of topotecan, as a second-line chemotherapeutic drug for small cell lung cancer, is ~20%. DNA/RNA helicase SLFN11 (schlafen family member 11), a member of the Schlafen (SLFN) family, is a crucial determinant of response to many DNA damaging agents, expression of SLFN11 tends to augment the antitumor effects of the commonly used DNA-targeting agents. In the present study we investigated how SLFN11 expression regulated the sensitivity of small cell lung cancer to topotecan. We showed that SLFN11 expression levels were positively associated with the sensitivity to topotecan in a panel of seven SCLC cell lines. Topotecan treatment induced different patterns of the DNA response network in SCLC cells: DNA damage response (DDR) was more prominently activated in SLFN11-deficient SCLC cell line H82 than in SLFN11-plentiful SCLC cell line DMS273, whereas topotecan induced significant accumulation of p-Chk1, p-RPA2 and Rad51 in H82 cells, but not in DMS273 cells. We unraveled that SLFN11 expression was highly negatively correlated to the methylation of the SLFN11 promoter. HDAC inhibitors FK228 and SAHA dose-dependently increased SLFN11 expression through suppressing DNA methylation at the SLFN11 promoter, thereby sensitizing SCLC cells to topotecan. Finally, we assessed the methylation status of the SLFN11 promoter in 27 SCLC clinical specimens, and found that most of the clinical samples (24/27) showed DNA methylation at the SLFN11 promoter. In conclusion, it is feasible to combine topotecan with FK228 to improve the response rate of topotecan in SCLC patients.

Potential of Stem Cells and CART as a Potential Polytherapy for Small Cell Lung Cancer

Despite the increasing urgency of the problem of treating small cell lung cancer (SCLC), information on the causes of its development is fragmentary. There is no complete understanding of the features of antitumor immunity and the role of the microenvironment in the development of SCLC resistance. This impedes the development of new methods for the diagnosis and treatment of SCLC. Lung cancer and chronic obstructive pulmonary disease (COPD) have common pathogenetic factors. COPD is a risk factor for lung cancer including SCLC. Therefore, the search for effective approaches to prevention, diagnosis, and treatment of SCLC in patients with COPD is an urgent task. This review provides information on the etiology and pathogenesis of SCLC, analyses the effectiveness of current treatment options, and critically evaluates the potential of chimeric antigen receptor T cells therapy (CART therapy) in SCLC. Moreover, we discuss potential links between lung cancer and COPD and the role of endothelium in the development of COPD. Finally, we propose a new approach for increasing the efficacy of CART therapy in SCLC.

Sox2 Is an Oncogenic Driver of Small-Cell Lung Cancer and Promotes the Classic Neuroendocrine Subtype

Although many cancer prognoses have improved in the past 50 years due to advancements in treatments, there has been little improvement in therapies for small-cell lung cancer (SCLC). One promising avenue to improve treatment for SCLC is to understand its underlying genetic alterations that drive its formation, growth, and cellular heterogeneity. RB1 loss is one key driver of SCLC, and RB1 loss has been associated with an increase in pluripotency factors such as SOX2. SOX2 is highly expressed and amplified in SCLC and has been associated with SCLC growth. Using a genetically engineered mouse model, we have shown that Sox2 is required for efficient SCLC formation. Furthermore, genome-scale binding assays have indicated that SOX2 can regulate key SCLC pathways such as NEUROD1 and MYC. These data suggest that SOX2 can be associated with the switch of SCLC from an ASCL1 subtype to a NEUROD1 subtype. Understanding this genetic switch is key to understanding such processes as SCLC progression, cellular heterogeneity, and treatment resistance. IMPLICATIONS: Understanding the molecular mechanisms of SCLC initiation and development are key to opening new potential therapeutic options for this devastating disease.

MAPK pathway activation selectively inhibits ASCL1-driven small cell lung cancer

Activation of mitogenic signaling pathways is a common oncogenic driver of many solid tumors including lung cancer. Although activating mutations in the mitogen-activated protein kinase (MAPK) pathway are prevalent in non-small cell lung cancers, MAPK pathway activity, counterintuitively, is relatively suppressed in the more aggressively proliferative small cell lung cancer (SCLC). Here, we elucidate the role of the MAPK pathway and how it interacts with other signaling pathways in SCLC. We find that the most common SCLC subtype, SCLC-A associated with high expression of ASCL1, is selectively sensitive to MAPK activation in vitro and in vivo through induction of cell-cycle arrest and senescence. We show strong upregulation of ERK negative feedback regulators and STAT signaling upon MAPK activation in SCLC-A lines. These findings provide insight into the complexity of signaling networks in SCLC and suggest subtype-specific mitogenic vulnerabilities.

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MAPK activation causes cell-cycle arrest and senescence selectively in SCLC-A subtype

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MAPK-induced growth inhibition is independent of NOTCH signaling

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MAPK activation increases ERK negative feedback and activates STAT3 signaling

Tumor Necrosis Factor Family Member Profile Predicts Prognosis and Adjuvant Chemotherapy Benefit for Patients With Small-Cell Lung Cancer

Tumor necrosis factor (TNF) family members participate in the body's antitumor immunity response and influence tumor prognosis and treatment response. However, little is known about the roles of TNF family members in small cell lung cancer (SCLC). Therefore, we conducted the first comprehensive investigation of TNF family members in patients with SCLC, with the goal of using them to predict prognosis and chemotherapy benefit. Abnormal genetic alterations and expression of TNF family members were found to be widespread in SCLC patients. Using LASSO Cox regression analysis, we constructed a TNF family-based signature that separated SCLC patients in the training set (n=77) into high- and low-risk groups with distinct survival and chemotherapy benefit, and the signature was well-validated in the validation set (n=137) by RT-qPCR. Importantly, the signature exhibited superior predictive performance and was identified as a novel independent prognostic factor. Additionally, different immune phenotypes were found between the low-risk and high-risk groups, and high-risk patients had higher CMTM6 expression, suggesting that these patients could benefit from therapeutic methods targeting CMTM6. We constructed the first clinically applicable TNF family-based signature for predicting prognosis and chemotherapy benefit for patients with SCLC. The findings reported here provide a new method for predicting the prognosis of SCLC patients and optimizing clinical management.

Signatures of plasticity, metastasis, and immunosuppression in an atlas of human small cell lung cancer

Small cell lung cancer (SCLC) is an aggressive malignancy that includes subtypes defined by differential expression of ASCL1, NEUROD1, and POU2F3 (SCLC-A, -N, and -P, respectively). To define the heterogeneity of tumors and their associated microenvironments across subtypes, we sequenced 155,098 transcriptomes from 21 human biospecimens, including 54,523 SCLC transcriptomes. We observe greater tumor diversity in SCLC than lung adenocarcinoma, driven by canonical, intermediate, and admixed subtypes. We discover a PLCG2-high SCLC phenotype with stem-like, pro-metastatic features that recurs across subtypes and predicts worse overall survival. SCLC exhibits greater immune sequestration and less immune infiltration than lung adenocarcinoma, and SCLC-N shows less immune infiltrate and greater T cell dysfunction than SCLC-A. We identify a profibrotic, immunosuppressive monocyte/macrophage population in SCLC tumors that is particularly associated with the recurrent, PLCG2-high subpopulation.

Effect of prior thoracic radiotherapy on prognosis in relapsed small cell lung cancer patients treated with anlotinib: a subgroup analysis of the ALTER 1202 trial

Background

In ALTER 1202, anlotinib prolonged the progression-free survival (PFS) and overall survival (OS) of patients with relapsed small cell lung cancer (SCLC). The aim of this study was to explore the effect of front-line thoracic radiotherapy (RT) on the benefits of anlotinib as a third-line-or-beyond treatment.

Methods

This was a subgroup analysis of a multicenter, randomized, double-blind, placebo-controlled phase 2 trial (ALTER 1202). The participants were divided into RT (previous thoracic RT) and non-RT subgroups. The outcomes included PFS, OS, objective response rate (ORR), disease control rate (DCR), and safety.

Results

In the ALTER 1202 trial, 68 participants (anlotinib, n=46; placebo, n=22) received RT and 51 participants (anlotinib, n=35; placebo, n=16) did not. PFS was longer for anlotinib versus placebo in both the RT (5.49 vs. 0.69 months; P<0.001) and non-RT (2.83 vs. 0.76 months; P<0.001) subgroups. In the RT subgroup, the OS was longer for anlotinib vs. placebo (9.49 vs. 4.90 months; P=0.039). No differences were found in the ORR, but the DCR was higher in the anlotinib arm of the RT subgroup compared with the placebo arm (73.9% vs. 9.1%, P<0.001) and the non-RT subgroup (68.6% vs. 18.8%; P=0.002).

Conclusions

In relapsed SCLC patients with previous thoracic RT, anlotinib might have DCR, PFS, and OS benefits compared with placebo. In those without previous thoracic RT patients, anlotinib might have DCR and PFS benefits compared with placebo. The safety was similar between anlotinib and placebo groups.

The diagnostic value of the combination of carcinoembryonic antigen, squamous cell carcinoma-related antigen, CYFRA 21-1, neuron-specific enolase, tissue polypeptide antigen, and progastrin-releasing peptide in small cell lung cancer discrimination

BACKGROUND

The diagnostic value of six tumor markers was investigated and the appropriate combinations of those tumor markers to discriminate small cell lung cancer was explored.

METHODS

Patients suspected with lung cancer (1938) were retrospectively analyzed. Candidate tumor markers from carcinoembryonic antigen (CEA), squamous cell carcinoma-related antigen (SCC), cytokeratin 19 fragment 21-1 (CYFRA 21-1), neuron-specific enolase (NSE), tissue polypeptide antigen (TPA), and progastrin releasing peptide (ProGRP) were selected to construct a logistic regression model. The receiver operating characteristic curve was used for evaluating the diagnostic value of the tumor markers and the predictive model.

RESULTS

ProGRP had the highest positive rate (72.3%) in diagnosed small cell lung cancer, followed by neuron-specific enolase (68.3%), CYFRA21-1 (50.5%), carcinoembryonic antigen (45.5%), tissue polypeptide antigen (30.7%), and squamous cell carcinoma-related antigen (5.9%). The predictive model for small cell lung cancer discrimination was established, which yielded the highest area under the curve (0.888; 95% confidence interval: 0.846-0.929), with a sensitivity of 71.3%, a specificity of 95.0%, a positive predictive value of 49.0%, and a negative predictive value of 98.0%.

CONCLUSIONS

Combining tumor markers can improve the efficacy for small cell lung cancer discrimination. A predictive model has been established in small cell lung cancer differential diagnosis with preferable efficacy.

What Are the Biomarkers for Immunotherapy in SCLC?

Small-cell lung cancer (SCLC) is an aggressive malignancy that exhibits a rapid doubling time, a high growth fraction, and the early development of widespread metastases. The addition of immune checkpoint inhibitors to first-line chemotherapy represents the first significant improvement of systemic therapy in several decades. However, in contrast to its effects on non-SCLC, the advantageous effects of immunotherapy addition are modest in SCLC. In particular, only a small number of SCLC patients benefit from immune checkpoint inhibitors. Additionally, biomarkers selection is lacking for SCLC, with clinical trials largely focusing on unselected populations. Here, we review the data concerning the major biomarkers for immunotherapy, namely, programmed death ligand 1 expression and tumour mutational burden. Furthermore, we explore other potential biomarkers, including the role of the immune microenvironment in SCLC, the role of genetic alterations, and the potential links between neurological paraneoplastic syndromes, serum anti-neuronal nuclear antibodies, and outcomes in SCLC patients treated with immunotherapy.

Salivary Biomarkers in Lung Cancer

A very low percentage of lung cancer (LC) cases are discovered at an early and treatable stage of the disease, leading to an abysmally low 5-year survival rate. This underscores the immediate necessity for improved diagnostic, prognostic, and predictive biomarkers for LC. Biopsied lung tissue, blood, and plasma are common sources used for LC diagnosis and monitoring of the disease. A growing number of studies have reported saliva to be a useful biological sample for early and noninvasive detection of oral and systemic diseases. Nevertheless, salivary biomarker discovery remains underresearched. Here, we have compiled the available literature to provide an overview of the current understanding of salivary markers for LC detection and provided perspectives for future clinical significance. Valuable markers with diagnostic and prognostic potentials in LC have been discovered in saliva, including metabolic (catalase activity, triene conjugates, and Schiff bases), inflammatory (interleukin 10, C-X-C motif chemokine ligand 10), proteomic (haptoglobin, zinc-α-2-glycoprotein, and calprotectin), genomic (epidermal growth factor receptor), and microbial candidates (Veillonella and Streptococcus). In combination, with each other and with other established screening methods, these salivary markers could be useful for improving early detection of the disease and ultimately improve the survival odds of LC patients. The existing literature suggests that saliva is a promising biological sample for identification and validation of biomarkers in LC, but how saliva can be utilized most effectively in a clinical setting for LC management is still under investigation.

The Feasibility of Using Biomarkers Derived from Circulating Tumor DNA Sequencing as Predictive Classifiers in Patients with Small-Cell Lung Cancer

Purpose

To investigate the feasibility of biomarkers based on dynamic circulating tumor DNA (ctDNA) to classify small cell lung cancer (SCLC) into different subtypes.

Materials and Methods

Tumor and longitudinal plasma ctDNA samples were analyzed by next-generation sequencing of 1,021 genes. PyClone was used to infer the molecular tumor burden index (mTBI). Pre-treatment tumor tissues [T1] and serial plasma samples were collected (pre-treatment [B1], after two [B2], six [B3] cycles of chemotherapy and at progression [B4]).

Results

Overall concordance between T1 and B1 sequencing (n=30) was 66.5%, and 89.5% in the gene of RB1. A classification method was designed according to the changes of RB1 mutation, named as subtype Ⅰ (both positive at B1 and B2), subtype Ⅱ (positive at B1 but negative at B2), and subtype Ⅲ (both negative at B1 and B2). The median progressive-free survival for subtype Ⅰ patients (4.5 months [95%CI: 2.6-5.8]) was inferior to subtype Ⅱ (not reached, p<0.0001) and subtype Ⅲ (10.8 months [95%CI: 6.0-14.4], p=0.002). The median overall survival for subtype Ⅰ patients (16.3 months [95%CI: 5.3-22.9]) was inferior to subtype Ⅱ (not reached, p=0.01) and subtype Ⅲ (not reached, p=0.02). Patients with a mTBI dropped to zero at B2 had longer median overall survival (not reached vs. 19.5 months, p=0.01). The changes of mTBI from B4 to B1 were sensitive to predict new metastases, with a sensitivity of 100% and a specificity of 85.7%.

Conclusion

Monitoring ctDNA based RB1 mutation and mTBI provided a feasible tool to predict the prognosis of SCLC.

Discovery of a novel CDK7 inhibitor YPN-005 in small cell lung cancer

In contrast to non-small cell lung cancer, there has been no significant progress in the development of therapies for the small cell lung cancer (SCLC) in recent decades. Although various targeted agents, including immunotherapies, have recently been developed for testing in clinical trials, novel therapeutic agents are still needed for SCLC. We developed a potent inhibitor of cyclin-dependent kinase 7 (CDK7), designated YPN-005, and sought to determine whether it showed any anticancer effects in SCLC cells, cisplatin or etoposide-resistant cells, or organoids derived from SCLC patients. In a panel of kinases assay, YPN-005 was highly selective for CDK7 and showed antiproliferative effects in SCLC and cells with acquired resistance to conventional anticancer drugs. Similar to other CDK7 inhibitors, YPN-005 treatment significantly decreased the phosphorylation of the carboxyl-terminal domain of RNA polymerase II. Consistent with the in vitro results, YPN-005 treatment showed a significant inhibition of tumor growth through the suppression of RNA polymerase II phosphorylation. Finally, YPN-005 showed potent anticancer effects in organoids derived from SCLC patients compared to another CDK7 inhibitor, THZ1. Therapeutic targeting of CDK7 in SCLC might be suitable for clinical investigation, and YPN-005 may be a promising therapeutic option for primary SCLC and SCLC with acquired resistance to conventional therapy.

Absence of Biomarker-Driven Treatment Options in Small Cell Lung Cancer, and Selected Preclinical Candidates for Next Generation Combination Therapies

Lung cancer is the second most common cancer in the United States, and small cell lung cancer (SCLC) accounts for about 15% of all lung cancers. In SCLC, more than other malignancies, the standard of care is based on clinical demonstration of efficacy, and less on a mechanistic understanding of why certain treatments work better than others. This is in large part due to the virulence of the disease, and lack of clinically or biologically relevant biomarkers beyond routine histopathology. While first line therapies work in the majority of patients with extensive stage disease, development of resistance is nearly universal. Although neuroendocrine features, Rb and p53 mutations are common, the current lack of actionable biomarkers has made it difficult to develop more effective treatments. Some progress has been made with the application of immune checkpoint inhibitors. There are new agents, such as lurbinectedin, that have completed late-phase clinical testing while other agents are still in the pre-clinical phase. ONC201/TIC10 is an imipridone with strong in vivo and in vitro antitumor properties and activity against neuroendocrine tumors in phase 1 clinical testing. ONC201 activates the cellular integrated stress response and induces the TRAIL pro-apoptotic pathway. Combination treatment of lurbinectedin with ONC201 are currently being investigated in preclinical studies that may facilitate translation into clinical trials for SCLC patients.

Prognostic indicators of survival in patients with small-cell lung cancer at a tertiary care center in Lebanon

Objective:

Small-cell lung cancer is a very aggressive tumor associated with high invasiveness and ease of metastasis and therefore poor prognosis. In the literature, several demographical, clinical as well as pathological factors including age, stage, gender and smoking were cited as independent prognosticators of survival.

Material and Methods:

This is a retrospective cohort study that includes 222 patients diagnosed with small-cell lung cancer between 2010 and 2019. Clinical and demographic data were extracted from their medical records. The Kaplan–Meier and logistic regression models of statistical analysis were used to evaluate the association of these variables with survival.

Results:

Forty-five percent of patients were found to be alive at the time of data collection. The median survival of patients with small-cell lung cancer was found to be 14 months. On univariate analysis, increasing age as well as stage (extensive disease) were found to be significantly associated with decreased survival at 3 years. On the contrary, both gender and smoking status at diagnosis were not shown to significantly influence survival. On multivariate analysis, both age as well as stage remained significantly associated with survival.

Conclusion:

Limited data exist in the literature regarding the prognostic indicators of survival in small-cell lung cancer, especially from the Middle East area. In our study, both age and stage at the time of diagnosis were found to significantly influence survival. Further studies are needed to assess the association of other factors with survival.

Cost-Effectiveness Analysis of Durvalumab Plus Chemotherapy in the First-Line Treatment of Extensive-Stage Small Cell Lung Cancer

BACKGROUND

In the CASPIAN trial, durvalumab + chemotherapy demonstrated significant improvements in overall survival compared with chemotherapy alone in patients with extensive-stage small cell lung cancer (SCLC). We aimed to assess the cost-effectiveness of durvalumab in patients with extensive-stage SCLC from the US healthcare system perspective.

PATIENTS AND METHODS

A comprehensive Markov model was adapted to evaluate cost and effectiveness of durvalumab combination versus platinum/etoposide alone in the first-line therapy of extensive-stage SCLC based on data from the CASPIAN study. The main endpoints included total costs, life years (LYs), quality-adjusted life-years (QALYs), and incremental cost-e-ectiveness ratios (ICERs). Model robustness was assessed with sensitivity analysis, and additional subgroup analyses were also performed.

RESULTS

Durvalumab + chemotherapy therapy resulted in an additional 0.27 LYs and 0.20 QALYs, resulting in an ICER of $464,711.90 per QALY versus the chemotherapy treatment. The cost of durvalumab has the greatest influence on this model. Subgroup analyses showed that the ICER remained higher than $150,000/QALY (the willingness-to-pay threshold in the United States) across all patient subgroups.

CONCLUSIONS

Durvalumab in combination with platinum/etoposide is not a cost-effective option in the first-line treatment of patients with extensive-stage SCLC.

Combinations of proteasome inhibitors with obatoclax are effective for small cell lung cancer

Proteasome inhibitors, bortezomib (BTZ), and carfilzomib (CFZ) are approved drugs for hematological malignancies, but lack anticancer activities against most solid tumors. Small cell lung cancer (SCLC) is a very aggressive neuroendocrine carcinoma of the lungs demanding effective therapy. In this study we investigated whether BTZ or CFZ combined with obatoclax (OBX), an antagonist for MCL-1 and a pan-BCL family inhibitor, could cause synergistic growth inhibition of SCLC cells. We showed that combined application of BTZ or CFZ with OBX caused synergistic growth inhibition of human SCLC cell lines (H82, H526, DMS79, H196, H1963, and H69) than single agent alone. Both BTZ-OBX and CFZ-OBX combinations displayed marked synergism on inducing apoptosis (~50% increase vs BTZ or CFZ alone). A comprehensive proteomics analysis revealed that BTZ preferentially induced the expression of MCL-1, an antiapoptotic protein, in SCLC cells. Thus, proteasome inhibitor-OBX combinations could specifically induce massive growth inhibition and apoptosis in SCLC cells. Subsequent proteome-wide profiling analysis of activated transcription factors suggested that BTZ- or CFZ-induced MCL-1 upregulation was transcriptionally driven by FOXM1. In nude mice bearing in SCLC H82 xenografts, both BTZ-OBX, and CFZ-OBX combinations exhibited remarkable antitumor activities against SCLC tumors evidenced by significant reduction of tumor size and the proliferation marker Ki-67 signals in tumor tissues as compared with single agent alone. Thus, proteasome inhibitor-OBX combinations are worth immediate assessments for SCLC in clinical settings.

Antitumor effects of 3-bromoascochlorin on small cell lung cancer via inhibiting MAPK pathway

Small cell lung cancer (SCLC) was defined as a recalcitrant cancer, and novel therapies are urgently needed. Marine natural products (MNPs) may bring continuing hope for treatment of SCLC. In this study, 3-bromoascochlorin (BAS), an MNP isolated from the coral-derived fungus Acremonium sclerotigenum GXIMD 02501, was primarily screened out with antiproliferative activity towards SCLC cell lines. Then western blot analysis (WB) and flow cytometry were conducted, and we found BAS could induce the apoptosis of H446 and H69AR cells. Besides, BAS could suppress the invasion and migration of H446. In an SCLC xenograft mice model, BAS inhibited the growth of tumor without affecting the body weight of mice. Finally, the underlying mechanisms were preliminarily explored. According to the results of RNA-seq, reverse transcription-quantitative polymerase chain reaction, and WB, our results revealed that BAS exerted antitumor activity via inhibiting mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinases (ERK) pathway. Collectively, these results indicated that BAS can be used as a promising compound for the treatment of human SCLC.

YAP1 protein expression has variant prognostic significance in small cell lung cancer (SCLC) stratified by histological subtypes

BACKGROUND

Recently, expression of YAP1, a nuclear effector of an inactivated HIPPO pathway, has been identified as one of four molecular subtypes of SCLC. However, the clinicopathological relevance and prognostic significance of YAP1 expression in SCLC stratified by histological subtypes has not been systematically reported to date.

METHODS

Tumor sections and corresponding formalin-fixed paraffin-embedded (FFPE) samples of 297 SCLC patients were retrieved from the pathological specimen repository and were subsequently reviewed by pathologists. Forty-six C-SCLCs (combined SCLCs) (15.5%) and 251P-SCLCs (pure SCLCs) (84.5%) were identified respectively. YAP1 expression was examined by immunohistochemistry (IHC) and assessed semi-quantitatively on tumor tissue array (TMA). Propensity score was used to match C-SCLCs and P-SCLCs in a ratio of 1 to 2 to balance age, gender, tumor stage and treatment methods. Finally, 46C-SCLCs and 92P-SCLCs were included for prognostic analysis.

RESULTS

The positive rate of YAP1 expression was significantly higher in C-SCLCs than P-SCLCs before matching (52.2% vs 29.1%, P = 0.004). After matching by propensity score, the prescribed clinical parameters were well balanced between P-SCLCs and C-SCLCs. Expression of YAP1 was associated worse overall survival (OS) (5- year OS%, 39.0% vs. 74.9%, P = 0.013) and was an independent risk factor for OS (HR = 2.93, 95% CI: 1.01-8.51; P = 0.048) exclusively in C-SCLC. Univariate survival analysis in subgroups of different clinical variables also confirmed the prognostic impact of YAP1 was most significant in C-SCLC. But for P-SCLCs, expression of YAP1 showed no prognostic impact.

CONCLUSIONS

Expression of YAP1 in small cell components of C-SCLC was significantly higher than that in P-SCLC. Besides, it served as an unfavorable predictor for OS in C-SCLC but not in P-SCLC, which suggested different entities of small cell components with variant YAP1 expression and potential different targetable oncogenic pathway between C-SCLC and P-SCLC.

Circulating progastrin-releasing peptide in the diagnosis of Small Cell Lung Cancer (SCLC) and in therapeutic monitoring

Introduction:

Progastrin-releasing peptide (proGRP), a precursor of GRP, has been recently reported as a putative circulating biomarker for differential diagnosis between non–small cell lung cancer (NSCLC) and SCLC. We evaluated the diagnostic effectiveness of proGRP to differentiate patients with NSCLC and SCLC and the usefulness of combined measurement of proGRP and neuron-specific enolase (NSE) for diagnosing SCLC.

Methods:

Serum proGRP, NSE, cytokeratin 19 fragment 21-1 (CYFRA 21.1), squamous cell carcinoma antigen (SCC Ag) and carcinoembryonic antigen (CEA) were prospectively collected and measured in patients with a new diagnosis of lung cancer. Serum proGRP was also measured in healthy subjects. The serum proGRP, NSE, CYFRA 21.1 and CEA concentrations were determined by an electrochemiluminescence immunoassay and the serum SCC Ag concentration was determined by an automated immunofluorescence assay. Differences between proGRP and NSE in patients with SCLC and NSCLC were evaluated and compared using Mann-Whitney test.

Results:

A total of 77 patients affected by SCLC (n = 17) and NSCLC (n = 60) were enrolled in the present study. Moreover, 50 cases of healthy subjects were analyzed for proGRP. SCLC patients showed a significantly higher proGRP (1,484 pg/mL; range 168-3,777) levels compared to NSCLC patients (45 pg/mL; range 31.7-60.6), p<0.0001. In healthy subjects the median proGRP level was 36.1 (28.8-43.5) pg/mL, significantly lower than SCLC patients. ProGRP showed a higher specificity when compared to NSE, with a difference in proportion of 47.5% (95% confidence interval 32.5% to 62.5%, p<0.001). Serial measurements of proGRP in SCLC patients showed a decrease in responsive chemotherapy patients.

Conclusions:

ProGRP is an accurate biomarker for diagnosis of SCLC and for discrimination of SCLC from NSCLC.

Durvalumab Plus Tremelimumab in Solid Tumors: A Systematic Review

INTRODUCTION

Cancer immunotherapy represents one of the most important innovations in modern medicine. Durvalumab is an anti-programmed cell death ligand 1 (PDL-1) agent which is currently under investigation in several studies in combination with the anti-cytotoxic T lymphocyte-associated protein 4 (CTLA-4) drug tremelimumab. The aim of this review was to systematically identify and revise the current scientific literature investigating the combination of these two drugs in solid tumors.

METHODS

A digital search on the Medline (PubMed interface) and Scopus databases for articles published from inception to 26 February 2021 was performed. The terms used for the search were durvalumab AND tremelimumab. Trials reported in English involving adult patients with solid cancers treated with the combination durvalumab plus tremelimumab were retrieved; the references of the articles were cross-checked to identify missing papers.

RESULTS

The electronic search produced 267 results; after exclusion of duplicates, irrelevant articles, reviews, and papers not in English or missing data, 19 articles were included for revision. The total number of patients treated with the combination of durvalumab and tremelimumab in the studies retrieved was 2052.

CONCLUSION

The combination of durvalumab plus tremelimumab showed some oncological advantages in comparison with traditional chemotherapies in some subsets of tumors, but generally has not shown consistent advantages in comparison with the employment of durvalumab monotherapy. A number of the studies examined had intrinsic methodological limitations; therefore, future well-designed studies involving larger cohorts are warranted.

How to Better Understand the Influence of Host Genetics on Developing an Effective Immune Response to Thoracic Cancers

Thoracic cancers pose a significant global health burden. Immune checkpoint blockade therapies have improved treatment outcomes, but durable responses remain limited. Understanding how the host immune system interacts with a developing tumor is essential for the rational development of improved treatments for thoracic malignancies. Recent technical advances have improved our understanding of the mutational burden of cancer cells and changes in cancer-specific gene expression, providing a detailed understanding of the complex biology underpinning tumor-host interactions. While there has been much focus on the genetic alterations associated with cancer cells and how they may impact treatment outcomes, how host genetics affects cancer development is also critical and will greatly determine treatment response. Genome-wide association studies (GWAS) have identified genetic variants associated with cancer predisposition. This approach has successfully identified host genetic risk factors associated with common thoracic cancers like lung cancer, but is less effective for rare cancers like malignant mesothelioma. To assess how host genetics impacts rare thoracic cancers, we used the Collaborative Cross (CC); a powerful murine genetic resource designed to maximize genetic diversity and rapidly identify genes associated with any biological trait. We are using the CC in conjunction with our asbestos-induced MexTAg mouse model, to identify host genes associated with mesothelioma development. Once genes that moderate tumor development and progression are known, human homologues can be identified and human datasets interrogated to validate their association with disease outcome. Furthermore, our CC-MexTAg animal model enables in-depth study of the tumor microenvironment, allowing the correlation of immune cell infiltration and gene expression signatures with disease development. This strategy provides a detailed picture of the underlying biological pathways associated with mesothelioma susceptibility and progression; knowledge that is crucial for the rational development of new diagnostic and therapeutic strategies. Here we discuss the influence of host genetics on developing an effective immune response to thoracic cancers. We highlight current knowledge gaps, and with a focus on mesothelioma, describe the development and application of the CC-MexTAg to overcome limitations and illustrate how the knowledge gained from this unique study will inform the rational design of future treatments of mesothelioma.

Prognostic role of pretreatment lung immune prognostic index in extensive-stage small-cell lung cancer treated with platinum plus etoposide chemotherapy

BACKGROUND

To investigate the prognostic role of lung immune prognostic index (LIPI) in extensive-stage small-cell lung cancer (ES-SCLC) patients treated with platinum plus etoposide chemotherapy.

METHODS

Data were obtained from two randomized controlled trials (NCT00119613 and NCT00363415). Overall survival (OS) and progression-free survival (PFS) was assessed according to LIPI score through Kaplan-Meier analysis. Univariate and multivariate Cox-regression analysis were performed to investigate predictors for OS and PFS.

RESULTS

A total of 911 patients with ES-SCLC treated with platinum plus etoposide chemotherapy (CT) were included for analysis. The median age at diagnosis was 62 years, and 760 (83.4%) had performance status of 1 or less. 1-year OS for ES-SCLC with poor, intermediate, and good LIPI was 20%, 30% and 31%, respectively, and 1-year PFS was 7%, 15% and 21%, respectively. Cox-regression analysis showed that the PFS and OS of ES-SCLC with a poor LIPI score was significantly worse than those with good LIPI scores (HR 1.81, 95% CI: 1.38-2.36; p< 0.001 and HR 1.35, 95% CI: 1.07-1.72, p= 0.012), while no significant difference was observed between intermediate and poor LIPI groups in terms of OS (HR 1.01, 95% CI: 0.82-1.23, p= 0.82), but not for PFS (HR 1.27, 95% CI: 1.00-1.61, p= 0.048). In addition, LIPI score was significantly associated with disease control rate and objective response rate (both p< 0.0001).

CONCLUSION

Prognosis of patients with pretreatment LIPI score of 2 is poorer than those with LIPI score of 0-1 among ES-SCLC who received first-line platinum plus etoposide chemotherapy; Further studies are still recommended to confirm our findings in prospective studies.

Epidemiology, treatment, and survival in small cell lung cancer in Spain: Data from the Thoracic Tumor Registry

BACKGROUND

Small-cell lung cancer (SCLC) is an aggressive disease with high metastatic potential and poor prognosis. Due to its low prevalence, epidemiological and clinical information of SCLC patients retrieved from lung cancer registries is scarce.

PATIENTS AND METHODS

This was an observational multicenter study that enrolled patients with lung cancer and thoracic tumors, recruited from August 2016 to January 2020 at 50 Spanish hospitals. Demographic and clinical data, treatment patterns and survival of SCLC patients included in the Thoracic Tumor Registry (TTR) were analyzed.

RESULTS

With a total of 956 cases, the age of 64.7 ± 9.1 years, 78.6% were men, 60.6% smokers, and ECOG PS 0, 1 or ≥ 2 in 23.1%, 53.0% and 23.8% of cases, respectively. Twenty percent of patients had brain metastases at the diagnosis. First-line chemotherapy (CT), mainly carboplatin or cisplatin plus etoposide was administered to >90% of patients. In total, 36.0% and 13.8% of patients received a second and third line of CT, respectively. Median overall survival was 9.5 months (95% CI 8.8-10.2 months), with an estimated rate of 70.3% (95% CI 67.2-73.4%), 38.9% (95% CI 35.4-42.4%), and 14.8% (95% CI 11.8-17.8%) at 6, 12 and 24 months respectively. Median progression-free survival was 6.3 months. Higher mortality and progression rates were significantly associated with male sex, older age, smoking habit, and ECOG PS 1-2. Long-term survival (> 2 years) was confirmed in 6.6% of patients, showing a positive correlation with better ECOG PS, poor smoking and absence of certain metastases at diagnosis.

CONCLUSION

This study provides an updated overview of the clinical situation and treatment landscape of ES-SCLC in Spain. Our results might assist oncologists to improve current clinical practice towards a better prognosis for these patients.

The multiple roles and therapeutic potential of clusterin in non-small-cell lung cancer: a narrative review

Worldwide, lung cancer is the most common form of cancer, with an estimated 2.09 million new cases and 1.76 million of death cause in 2018. It is categorized into two subtypes, small-cell lung cancer (SCLC) and non-small-cell lung cancer (NSCLC). Although platinum-based chemotherapy or molecular targeted drugs is recommended for advanced stages of NSCLC patients, however, resistance to drug and chemotherapy are hindrances for patients to fully beneficial from these treatments. Clusterin (CLU), also known as apolipoprotein J, is a versatile chaperone molecule which produced by a wide array of tissues and found in most biologic fluids. There are studies reported high expression of CLU confers resistance to chemotherapy and radiotherapy in different lung cancer cell lines. By silencing CLU using Custirsen (OGX-011), a second-generation antisense oligonucleotide (ASO) that inhibits CLU production, not only could sensitized cells to chemo- and radiotherapy, also could decreased their metastatic potential. We will review here the extensive literature linking CLU to NSCLC, update the current state of research on CLU for better understanding of this unique protein and the development of more effective anti- CLU treatment.

Toxicities of Immunotherapy for Small Cell Lung Cancer

Small cell lung cancer (SCLC), composing 15–20% of lung cancer, is a fatal disease with extremely poor prognosis. In the past two decades, etoposide platinum doublet chemotherapy remained the only choice of therapy, with disappointing overall survival ≤1 year for the metastatic disease. Novel treatments including immunotherapy are urgently needed and extensively explored. Recently, in two phase III trials, atezolizumab and durvalumab were shown to bring survival benefit to patients. While immunotherapy brings better outcome, it is accompanied by adverse events different from traditional treatments. Although these immune-related adverse events (irAEs) are generally mild and can be managed, some irAEs (myocarditis, pneumonitis) may be severe and even life-threatening. Accompanying with the increasing application of immunotherapy in clinical practice, the irAEs should not be overlooked. In this review, the irAEs profile in clinical trials of immunotherapy for SCLC will be summarized, also its unique features compared with irAEs in other malignancies will be explored. This review may be helpful for the appropriate clinical use of immunotherapy for SCLC.

Evaluation of the Small-molecule BRD4 Degrader CFT-2718 in Small-cell Lung Cancer and Pancreatic Cancer Models

Targeted, catalytic degradation of oncoproteins using heterobifunctional small molecules is an attractive modality, particularly for hematologic malignancies, which are often initiated by aberrant transcription factors and are challenging to drug with inhibitors. BRD4, a member of the bromodomain and extraterminal family, is a core transcriptional and epigenetic regulator that recruits the P-TEFb complex, which includes Cdk9 and cyclin T, to RNA polymerase II (pol II). Together, BRD4 and CDK9 phosphorylate serine 2 (pSer2) of heptad repeats in the C-terminal domain of RPB1, the large subunit of pol II, promote transcriptional elongation. Small-molecule degraders of BRD4 have shown encouraging efficacy in preclinical models for several tumor types but less efficacy in other cancers including small-cell lung cancer (SCLC) and pancreatic cancer. Here, we evaluated CFT-2718, a new BRD4-targeting degrader with enhanced catalytic activity and in vivo properties. In vivo, CFT-2718 has significantly greater efficacy than the CDK9 inhibitor dinaciclib in reducing growth of the LX-36 SCLC patient-derived xenograft (PDX) model and performed comparably to dinaciclib in limiting growth of the PNX-001 pancreatic PDX model. In vitro, CFT-2718 reduced cell viability in four SCLC and two pancreatic cancer models. In SCLC models, this activity significantly exceeded that of dinaciclib; furthermore, CFT-2718 selectively increased the expression of cleaved PARP, an indicator of apoptosis. CFT-2718 caused rapid BRD4 degradation and reduced levels of total and pSer2 RPB1 protein. These and other findings suggest that BRD-mediated transcriptional suppression merits further exploration in the setting of SCLC.

A comparative study of multiple instance learning methods for cancer detection using T-cell receptor sequences

As a branch of machine learning, multiple instance learning (MIL) learns from a collection of labeled bags, each containing a set of instances. The learning process is weakly supervised due to ambiguous instance labels. Since its emergence, MIL has been applied to solve various problems including content-based image retrieval, object tracking/detection, and computer-aided diagnosis. In biomedical research, the use of MIL has been focused on medical image analysis and molecule activity prediction. We review and apply 16 methods to investigate the applicability of MIL to a novel biomedical application, cancer detection using T-cell receptor (TCR) sequences. This important application can be a viable approach for large-scale cancer screening, as TCRs can be easily profiled from a subject's peripheral blood. We consider two feasible data-generating mechanisms, and for the purpose of performance evaluation, we simulate data under each mechanism, where we vary potentially important factors to mimic realistic situations. We also apply the methods to sequencing data of ten cancer types from The Cancer Genome Atlas, as an early proof of concept for distinguishing tumor patients from healthy individuals via TCR sequencing of peripheral blood. We find that given an appropriate MIL method is used, satisfactory performance with Area Under the Receiver Operating Characteristic Curve above 80% can be achieved for five in the ten cancers. Based on our numerical results, we make suggestions about selection of a proper method and avoidance of any method with poor performance. We further point out directions of future research as well as identify a pressing need of new MIL methodologies for improved performance (for some cancer types) and more explainable outcomes.

Cancer Testis Antigen, NOL4, Is an Immunogenic Antigen Specifically Expressed in Small-Cell Lung Cancer

To identify cancer/testis (CT) antigens and immunogenic proteins, immunoscreening of testicular and small-cell lung cancer cell line NCI-H889 cDNA libraries was performed using serum obtained from a small-cell lung cancer (SCLC) patient. We obtained 113 positive cDNA clones comprised of 74 different genes, designated KP-SCLC-1 through KP-SCLC-74. Of these genes, 59 genes were found to be related to cancers by EMBASE analysis. Three of these antigens, including KP-SCLC-29 (NOL4), KP-SCLC-59 (CCDC83), and KP-SCLC-69 (KIF20B), were CT antigens. RT-PCR and western blot analysis showed that NOL4 was frequently present in small-cell lung cancer cell lines (8/9, 8/9). In addition, NOL4 mRNA was weakly, or at a low frequency, or not detected in various cancer cell lines. Our results reveal that NOL4 was expressed at protein levels in small-cell lung cancer tissues (10/10) but not detected in lung adenocarcinoma and squamous cell carcinoma by immunohistochemical analysis. Serological response to NOL4 was also evaluated by western blot assay using NOL4 recombinant protein. A humoral response against NOL4 proteins was detected in 75% (33/44) of small-cell lung cancer patients and in 65% (13/20) of healthy donors by a serological western blot assay. These data suggest that NOL4 is a specific target that may be useful for diagnosis and immunotherapy in SCLC.

FOXP3-based immune risk model for recurrence prediction in small-cell lung cancer at stages I-III

BACKGROUND

Immunotherapies may prolong the survival of patients with small-cell lung cancer (SCLC) to some extent. The role of forkhead box protein P3 (FOXP3) in tumor microenvironment (TME) remains controversial. We aimed to examine FOXP3-related expression characteristics and prognostic values and to develop a clinically relevant predictive system for SCLC.

METHODS

We enrolled 102 patients with histologically confirmed SCLC at stages I-III. Through immunohistochemistry, we determined the expression pattern of FOXP3 and its association with other immune biomarkers. By machine learning and statistical analysis, we constructed effective immune risk score models. Furthermore, we examined FOXP3-related enrichment pathways and TME traits in distinct cohorts.

RESULTS

In SCLC, FOXP3 level was significantly associated with status of programmed death-ligand 1 (PD-L1), programmed cell death protein 1 (PD-1), CD4, CD8, and CD3 (p=0.002, p=0.001, p=0.002, p=0.030, and p<0.001). High FOXP3 expression showed longer relapse-free survival (RFS) than the low-level group (41.200 months, 95% CI 26.937 to 55.463, vs 14.000 months, 95% CI 8.133 to 19.867; p=0.008). For tumor-infiltrating lymphocytes (TILs), subgroup analysis demonstrated FOXP3 and PD-1, PD-L1, lymphocyte activation gene-3, CD3, CD4, or CD8 double positive were significantly correlated with longer RFS. We further performed importance evaluation for immune biomarkers, constructed an immune risk score incorporating the top three important biomarkers, FOXP3, TIL PD-L1, and CD8, and found their independently prognostic role to predict SCLC relapse. Better predictive performance was achieved in this immune risk model compared with single-indicator-based or two-indicator-based prediction systems (area under the curve 0.715 vs 0.312-0.711). Then, relapse prediction system integrating clinical staging and immune risk score was established, which performed well in different cohorts. High FOXP3-related genes were enriched in several immune-related pathways, and the close relationships of interleukin-2, CD28, basic excision repair genes MUTYH, POLD1, POLD2, and oxidative phosphorylation related gene cytochrome c oxidase subunit 8A with FOXP3 expression were revealed. Moreover, we found low-immune risk score group had statistically higher activated CD4⁺ memory T cells (p=0.014) and plasma cells (p=0.049) than the high-risk group. The heterogeneity of tumor-infiltrating immune cells might represent a promising feature for risk prediction in SCLC.

CONCLUSION

FOXP3 interacts closely with immune biomarkers on tumor-infiltrating cells in TME. This study highlighted the crucial prognostic value and promising clinical applications of FOXP3 in SCLC.

Gangliosides as Signaling Regulators in Cancer

At the plasma membrane, gangliosides, a group of glycosphingolipids, are expressed along with glycosphingolipids, phospholipids, and cholesterol in so-called lipid rafts that interact with signaling receptors and related molecules. Most cancers present abnormalities in the intracellular signal transduction system involved in tumor growth, invasion, and metastasis. To date, the roles of gangliosides as regulators of signal transduction have been reported in several cancer types. Gangliosides can be expressed by the exogenous ganglioside addition, with their endogenous expression regulated at the enzymatic level by targeting specific glycosyltransferases. Accordingly, the relationship between changes in the composition of cell surface gangliosides and signal transduction has been investigated by controlling ganglioside expression. In cancer cells, several types of signaling molecules are positively or negatively regulated by ganglioside expression levels, promoting malignant properties. Moreover, antibodies against gangliosides have been shown to possess cytotoxic effects on ganglioside-expressing cancer cells. In the present review, we highlight the involvement of gangliosides in the regulation of cancer cell signaling, and we explore possible therapies targeting ganglioside-expressing cancer.

DHODH and cancer: promising prospects to be explored

Human dihydroorotate dehydrogenase (DHODH) is a flavin-dependent mitochondrial enzyme catalyzing the fourth step in the de novo pyrimidine synthesis pathway. It is originally a target for the treatment of the non-neoplastic diseases involving in rheumatoid arthritis and multiple sclerosis, and is re-emerging as a validated therapeutic target for cancer therapy. In this review, we mainly unravel the biological function of DHODH in tumor progression, including its crucial role in de novo pyrimidine synthesis and mitochondrial respiratory chain in cancer cells. Moreover, various DHODH inhibitors developing in the past decades are also been displayed, and the specific mechanism between DHODH and its additional effects are illustrated. Collectively, we detailly discuss the association between DHODH and tumors in recent years here, and believe it will provide significant evidences and potential strategies for utilizing DHODH as a potential target in preclinical and clinical cancer therapies.

KCNQ1OT1 lncRNA affects the proliferation, apoptosis, and chemoresistance of small cell lung cancer cells via the JAK2/STAT3 axis

Background

Small cell lung cancer (SCLC) is a devastating and aggressive neuroendocrine carcinoma characterized by high cellular proliferation and early metastatic spread. Numerous studies have demonstrated that long noncoding RNAs (lncRNAs) can regulate tumor generation and development, including in SCLC. The current study aimed to assess the effect of the lncRNA, KCNQ1OT1, on the proliferation, apoptosis, and chemoresistance of SCLC and the potential underlying molecular mechanism.

Methods

Matched chemo-resistant and sensitive cells were applied to RNA isolation and followed by expression profiling by microarray analysis and subsequent quantitative polymerase chain reaction (qPCR) validation. Cell viability and apoptosis were determined by Cell Counting Kit-8 and flow cytometry to examine the chemoresistance and apoptosis of KCNQ1OT1 knockdown with lentivirus-mediated RNA interference. Furthermore, cell proliferation was studied by colony formation, and invasion and migration were tested by Transwell cell invasion and wound-healing assays, respectively. A tumor xenograft model was established to determine the role of KCNQ1OT1 in tumor growth and chemoresistance in response to KCNQ1OT1 knockdown in vivo. Western blot analysis, qPCR, and immunohistochemistry were used to detect the levels of messenger RNA (mRNA) Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway-related markers.

Results

Higher expression of KCNQ1OT1 was detected in SCLC chemo-resistant verso chemo-sensitive cells. Knockdown of KCNQ1OT1 inhibited SCLC cell viability and cloning ability, hindered cell migration and invasion, induced apoptosis in vitro, and suppressed tumor growth and chemoresistance in vivo, by activating the JAK2/STAT3 signaling pathway.

Conclusions

This is the first study to indicate that lncRNA KCNQ1OT1 promotes cell proliferation and invasion, and prevents apoptosis of SCLC by activating the JAK2/STAT3 pathway.

Efficacy and Safety of Niraparib as Maintenance Treatment in Patients With Extensive-Stage SCLC After First-Line Chemotherapy: A Randomized, Double-Blind, Phase 3 Study

INTRODUCTION

ZL-2306-005 is a randomized, double-blind, multicenter phase 3 study evaluating the efficacy and safety of niraparib, a poly(adenosine diphosphate-ribose) polymerase inhibitor, as first-line maintenance therapy in Chinese patients with platinum-responsive, extensive-stage SCLC (ES-SCLC).

METHODS

Patients with complete response (CR) or partial response (PR) to standardized, platinum-based first-line chemotherapy were randomized 2:1 to receive niraparib or placebo (300 mg [baseline body weight ≥ 77 kg, platelet count ≥ 150,000/μL] or 200 mg) once daily until progression or unacceptable toxicity. Primary end points were progression-free survival (PFS) (blinded independent central review) and overall survival (sample size planned: 591 patients). Secondary end points included investigator-evaluated PFS and safety.

RESULTS

ZL-2306-005 was terminated early owing to ES-SCLC treatment landscape changes (data cutoff: March 20, 2020). During July 2018-February 2020, a total of 185 of 272 patients screened were randomized (niraparib: n = 125 [CR = 1, PR = 124]; placebo: n = 60 [CR = 1, PR = 59]). Median (95% confidence interval [CI]) PFS (blinded independent central review) was 1.54 months (1.41-2.69, niraparib) and 1.36 months (1.31-1.48, placebo); hazard ratio (HR) = 0.66 (95% CI: 0.46-0.95, p = 0.0242). Median overall survival was 9.92 months (9.33-13.54, niraparib) and 11.43 months (9.53-not estimable, placebo); HR = 1.03 (95% CI: 0.62-1.73, p = 0.9052). Median investigator-evaluated PFS was 1.48 months (1.41-2.56, niraparib) and 1.41 months (1.31-2.00, placebo); HR = 0.88 (95% CI: 0.61-1.26; p = 0.4653). Grade greater than or equal to 3 adverse events occurred in 34.4% (niraparib) and 25.0% (placebo) of patients.

CONCLUSIONS

ZL-2306-005 did not reach primary end points. Nevertheless, niraparib as maintenance therapy modestly improved PFS in patients with platinum-responsive ES-SCLC, with acceptable tolerability profile and no new safety signal.

A Phase II Trial of Prexasertib (LY2606368) in Patients With Extensive-Stage Small-Cell Lung Cancer

BACKGROUND

This study assessed the checkpoint kinase 1 inhibitor prexasertib in patients with extensive-stage small-cell lung cancer (ED-SCLC).

PATIENTS AND METHODS

This was a parallel-cohort phase II study of 105 mg/m² prexasertib once every 14 days for patients who progressed after no more than two prior therapies and had platinum-sensitive (Cohort 1) or platinum-resistant/platinum-refractory (Cohort 2) disease. The primary endpoint was objective response rate (ORR). Secondary endpoints included disease control rate (DCR), progression-free survival (PFS), overall survival (OS), safety, and pharmacokinetics. Exploratory endpoints included biomarker identification and assessment of an alternative regimen (Cohort 3: 40 mg/m² days 1-3, 14-day cycle).

RESULTS

In Cohort 1 (n = 58), ORR was 5.2%; DCR, 31%; median PFS, 1.41 months (95% confidence interval [CI], 1.31-1.64); and median OS, 5.42 months (95% CI, 3.75-8.51). In Cohort 2 (n = 60), ORR was 0%; DCR, 20%; median PFS, 1.36 months (95% CI, 1.25-1.45); and median OS, 3.15 months (95% CI, 2.27-5.52). The most frequent all-grade, related, treatment-emergent adverse events were decreased neutrophil count (Cohort 1, 69.6%; Cohort 2, 73.3%), decreased platelet count (Cohort 1, 51.8%; Cohort 2, 50.0%), decreased white blood cell count (Cohort 1, 28.6%; Cohort 2, 40.0%), and anemia (Cohort 1, 39.3%; Cohort 2, 28.3%). Eleven patients (19.6%) in Cohort 1 and one patient (1.7%) in Cohort 2 experienced grade ≥3 febrile neutropenia. Prexasertib pharmacokinetics were consistent with prior studies. Cohort 3 outcomes were similar to those of Cohorts 1 and 2. No actionable biomarkers were identified.

CONCLUSION

Prexasertib did not demonstrate activity to warrant future development as monotherapy in ED-SCLC.

Small Cell Lung Cancer: State of the Art of the Molecular and Genetic Landscape and Novel Perspective

Simple Summary

Small cell lung cancer (SCLC) continues to carry a poor prognosis with a five-year survival rate of 3.5% and a 10-year survival rate of 1.8%. The pathogenesis remains unclear, and there are no known predictive or diagnostic biomarkers. The current SCLC classification as a single entity hinders effective targeted therapies against this heterogeneous neoplasm. Despite dedicated decades of research and clinical trials, there has been no change in the SCLC treatment paradigm. This review summarizes the body of literature available on SCLC’s genomic landscape to describe SCLC’s molecular/genetic aspects, regardless of therapeutic strategy.

Abstract

Small cell lung cancer (SCLC) is a highly proliferative lung cancer that is not amenable to surgery in most cases due to the high metastatic potential. Precision medicine has not yet improved patients’ survival due to the lack of actionable mutations. Intra- and intertumoral heterogeneity allow the neoplasms to adapt to various microenvironments and treatments. Further studying this heterogeneous cancer might yield the discovery of actionable mutations. First-line SCLC treatment has added immunotherapy to its armamentarium. There has been renewed interest in SCLC, and numerous clinical trials are underway with novel therapeutic approaches. Understanding the molecular and genetic landscape of this heterogeneous and lethal disease will pave the way for novel drug development.

Prognostic factors and survival after whole-brain radiotherapy for initial brain metastases arising from non-small cell lung cancer

Aim:

To identify prognostic factors and investigate patient survival after whole-brain radiotherapy (WBRT) for initial brain metastases arising from non-small cell lung cancer (NSCLC).

Methods:

Patients diagnosed with NSCLC between 1 January 2010 and 30 September 2019, and who received WBRT upon first developing a brain metastasis, were investigated. Overall survival was determined as related to age, sex, duration between initial examination and brain metastasis detection, stage at the first examination, presence of metastases outside the brain, blood analysis findings, brain metastasis symptoms, radiotherapy dose and completion, imaging findings, therapeutic course of chemotherapy and/or radiation therapy, histological type, and gene mutation status.

Results:

Thirty-one consecutive patients (20 men and 11 women) with a mean age of 63·8 years and median survival of 129 days were included. Multivariate analysis with stepwise testing was performed to investigate differences in survival according to gene mutation status, lactate dehydrogenase (LDH) level, irradiation dose, WBRT completion and Stage status. Of these, a statistically significant difference in survival was observed in patients with gene mutation status (hazard ratio: 0·31, 95% CI: 0·11–0·86, p = 0·025), LDH levels <230 vs. ≥230 IU/L (hazard ratio: 4·08, 95% CI: 1·45–11·5, p < 0·01) received 30 Gy, 30 Gy/10 fractions to 35 Gy/14 fractions, and 37·5 Gy/15 fractions (hazard ratio: 0·26, 95% CI: 0·09–0·71, p < 0·01), and stage IV versus non-stage IV (hazard ratio: 0·13, 95 CI:0·02–0·64, p < 0·01)

Findings:

Gene mutation, LDH, radiation dose and Stage are prognostic factors for patients with initial brain metastases who are treated with WBRT.

Advances in Small-Cell Lung Cancer (SCLC) Translational Research

Over the past several years, we have witnessed a resurgence of interest in the biology and therapeutic vulnerabilities of small-cell lung cancer (SCLC). This has been driven in part through the development of a more extensive array of representative models of disease, including a diverse variety of genetically engineered mouse models and human tumor xenografts. Herein, we review recent progress in SCLC model development, and consider some of the particularly active avenues of translational research in SCLC, including interrogation of intratumoral heterogeneity, insights into the cell of origin and oncogenic drivers, mechanisms of chemoresistance, and new therapeutic opportunities including biomarker-directed targeted therapies and immunotherapies. Whereas SCLC remains a highly lethal disease, these new avenues of translational research, bringing together mechanism-based preclinical and clinical research, offer new hope for patients with SCLC.

Assessment of systematic inflammatory and nutritional indexes in extensive-stage small-cell lung cancer treated with first-line chemotherapy and atezolizumab

BACKGROUND

The present study aims to investigate the prognostic role of systematic inflammatory and nutritional indexes in extensive-stage small-cell lung cancer (ES-SCLC) treated with first-line chemotherapy and atezolizumab.

MATERIALS AND METHODS

Prospective cohort population involving 53 patients were identified from NCT03041311 trial. The following peripheral blood-derived inflammatory and nutritional indexes, including neutrophil-lymphocyte ratio (NLR), platelet lymphocyte ratio (PLR), lymphocyte-monocyte ratio (LMR), systemic immune-inflammation index (SII), systemic inflammation response index (SIRI), prognostic nutrition index (PNI), advanced lung cancer inflammation index (ALI), and lung immune prognostic index (LIPI) were evaluated.

RESULTS

The optimal cut-off values of the ALI, LMR, NLR, PLR, PNI, SII and SIRI were 323.23, 2.73, 2.57, 119.23, 48, 533.28 and 2.32, respectively. With a median follow-up of 17.1 months, the 1-year OS and PFS were 56% and 8%, respectively. Multivariate analysis showed that PLR was the only independent prognostic factors for OS among ES-SCLC patients treated with chemotherapy and atezolizumab (HR 4.63, 95%CI: 1.00-21.46, p = 0.05). K-M analysis showed that the OS and PFS for patients with high PLR (> 119.23) were significantly poorer than these with low PLR (≤ 119.23) (p = 0.0004 for OS and p = 0.014 for PFS). In external validation set, prognosis of patients with high PLR was also significantly poorer than these with low PLR in terms of OS (p = 0.038) and PFS (p = 0.028).

CONCLUSION

Pre-treatment PLR could serve as a valuable independent prognostic factor for ES-SCLC who receive chemotherapy and immune checkpoint inhibitors. Further, prospective studies are still needed to confirm our findings.

Embolic Stroke Due to a Mural Thrombus in the Ascending Aorta Following Cisplatin-based Chemotherapy

A 59-year-old woman with small-cell lung carcinoma achieved tumor disappearance after cisplatin-based chemotherapy (CBC) and radiation treatment but subsequently experienced right hemiparesis and aphasia. Brain magnetic resonance imaging revealed a left middle cerebral artery territory acute infarction and left internal carotid artery occlusion. Ultrasonography revealed a mobile thrombus in the left common and internal carotid arteries, and contrast computed tomography revealed a mural thrombus in the ascending aorta. Based on these findings, embolic stroke due to aortic mural thrombus following CBC was diagnosed. Aortic mural thrombus is a rare complication of CBC but carries a risk of embolic stroke.

High-dose versus standard-dose twice-daily thoracic radiotherapy for patients with limited stage small-cell lung cancer: an open-label, randomised, phase 2 trial

BACKGROUND

Concurrent chemoradiotherapy is standard treatment for limited stage small-cell lung cancer (SCLC). Twice-daily thoracic radiotherapy of 45 Gy in 30 fractions is considered to be the most effective schedule. The aim of this study was to investigate whether high-dose, twice-daily thoracic radiotherapy of 60 Gy in 40 fractions improves survival.

METHODS

This open-label, randomised, phase 2 trial was done at 22 public hospitals in Norway, Denmark, and Sweden. Patients aged 18 years and older with treatment-naive confirmed limited stage SCLC, Eastern Cooperative Oncology Group (ECOG) performance status 0-2, and measurable disease according to the Response Evaluation Criteria in Solid Tumors version 1.1 were eligible. All participants received four courses of intravenous cisplatin 75 mg/m² or carboplatin (area under the curve 5-6 mg/mL × min, Calvert's formula) on day 1 and intravenous etoposide 100 mg/m² on days 1-3 every 3 weeks. Participants were randomly assigned (1:1) in permuted blocks (sized between 4 and 10) stratifying for ECOG performance status, disease stage, and presence of pleural effusion to receive thoracic radiotherapy of 45 Gy in 30 fractions or 60 Gy in 40 fractions to the primary lung tumour and PET-CT positive lymph node metastases starting 20-28 days after the first chemotherapy course. Patients in both groups received two fractions per day, ten fractions per week. Responders were offered prophylactic cranial irradiation of 25-30 Gy. The primary endpoint, 2-year overall survival, was assessed after all patients had been followed up for a minimum of 2 years. All randomly assigned patients were included in the efficacy analyses, patients commencing thoracic radiotherapy were included in the safety analyses. Follow-up is ongoing. This trial is registered at ClinicalTrials.gov, NCT02041845.

FINDINGS

Between July 8, 2014, and June 6, 2018, 176 patients were enrolled, 170 of whom were randomly assigned to 60 Gy (n=89) or 45 Gy (n=81). Median follow-up for the primary analysis was 49 months (IQR 38-56). At 2 years, 66 (74·2% [95% CI 63·8-82·9]) patients in the 60 Gy group were alive, compared with 39 (48·1% [36·9-59·5]) patients in the 45 Gy group (odds ratio 3·09 [95% CI 1·62-5·89]; p=0·0005). The most common grade 3-4 adverse events were neutropenia (72 [81%] of 89 patients in the 60 Gy group vs 62 [81%] of 77 patients in the 45 Gy group), neutropenic infections (24 [27%] vs 30 [39%]), thrombocytopenia (21 [24%] vs 19 [25%]), anaemia (14 [16%] vs 15 [20%]), and oesophagitis (19 [21%] vs 14 [18%]). There were 55 serious adverse events in 38 patients in the 60 Gy group and 56 serious adverse events in 44 patients in the 45 Gy group. There were three treatment-related deaths in each group (one neutropenic fever, one aortic dissection, and one pneumonitis in the 60 Gy group; one thrombocytic bleeding, one cerebral infarction, and one myocardial infarction in the 45 Gy group).

INTERPRETATION

The higher radiotherapy dose of 60 Gy resulted in a substantial survival improvement compared with 45 Gy, without increased toxicity, suggesting that twice-daily thoracic radiotherapy of 60 Gy is an alternative to existing schedules.

FUNDING

The Norwegian Cancer Society, The Liaison Committee for Education, Research and Innovation in Central Norway, the Nordic Cancer Union, and the Norwegian University of Science and Technology.