LBA86 Durvalumab (D) ± tremelimumab (T) + platinum-etoposide (EP) in 1L ES-SCLC: Characterization of long-term clinical benefit and tumour mutational burden (TMB) in CASPIAN

Facts and Hopes on Cancer Immunotherapy for Small Cell Lung Cancer

Platinum-based chemotherapy plus PD1 axis blockade is the standard of care in the first-line treatment of extensive-stage small cell lung cancer (SCLC). Despite the robust and consistent increase in long-term survival with PD1 axis inhibition, the magnitude of the benefit from immunotherapy seems lower than that for other solid tumors. Several immune evasive mechanisms have been shown to be prominently altered in human SCLC, including T-cell exclusion, downregulation of components of the MHC class I antigen processing and presentation machinery, or upregulation of macrophage inhibitory checkpoints, among others. New immunotherapies aiming to target some of these dominant immune suppressive features are being intensively evaluated preclinically and clinically in SCLC. They include strategies to enhance the efficacy and/or reverse features that promote intrinsic resistance to PD1 axis inhibition (e.g., restoring MHC class I deficiency and targeting DNA damage response) and novel immunomodulatory agents beyond T-cell checkpoint blockers (e.g., T cell-redirecting strategies, antibody-drug conjugates, or macrophage checkpoint blockers). Among them, delta-like ligand 3-targeted bispecific T-cell engagers have shown the most compelling preliminary evidence of clinical efficacy and hold promise as therapies that might contribute to further improve patient outcomes in this disease. In this study, we first provide a brief overview of key tumor microenvironment features of human SCLC. Then, we update the current clinical evidence with immune checkpoint blockade and review other emerging immunotherapy strategies that are gaining increasing attention in SCLC. We finally summarize our future perspective on immunotherapy and precision oncology for this disease.

Recent advances and future strategies in first-line treatment of ES-SCLC

Recent advancements in treating extensive-stage small-cell lung cancer (ES-SCLC) have been significantly marked by incorporating immune checkpoint inhibitors (ICIs) into platinum-based chemotherapy, leading to modest yet notable improvements in patient outcomes, which become more evident with longer follow-up. However, critical challenges persist, such as identifying effective biomarkers for accurate patient selection or finding more effective drugs. This review delves into the current and evolving treatment landscape for ES-SCLC, focusing on the most promising therapeutic strategies under investigation. We discuss the latest developments in the use of newer ICIs, antiangiogenic agents, PARP inhibitors (PARPi), lurbinectedin, and anti-DLL3 agents, offering insights into potential future directions in the management of this aggressive cancer.

Tissue and circulating biomarkers of benefit to immunotherapy in extensive-stage small cell lung cancer patients

Extensive stage-Small-Cell Lung Cancer (ES-SCLC) is an aggressive cancer with dismal prognosis. The addition of immune-checkpoint inhibitors (ICIs) to platinum-based chemotherapy have been consistently demonstrated to improve outcomes and survival, becoming the new standard in first - line treatment of ES-SCLC patients. However, despite positive results reported in the pivotal trials, longer benefit appears evident only for a selected group of patients. Several predictive biomarkers have been studied so far but the prospective identification of patients more likely to experience better outcome seems to be challenging in SCLC. Indeed, classical immune predictive biomarkers as PD-L1 and tumor mutational burden (TMB) seem not to correlate with outcomes. Recently, a new molecular classification of SCLC based on differential expression of genes associated with specific clinical behaviors and therapeutic vulnerability have been presented suggesting a new field to be investigated. Despite the achievements, these studies focused mainly on inter-tumoral heterogeneity, limiting the exploration of intra-tumoral heterogeneity and cell to cell interactions. New analysis methods are ongoing in order to explore subtypes plasticity. Analysis on single biopsies cannot catch the whole genomic profile and dynamic change of disease over time and during treatment. Moreover, the availability of tissue for translational research is limited due to the low proportion of patients undergoing surgery. In this context, liquid biopsy is a promising tool to detect reliable predictive biomarkers. Here, we reviewed the current available data on predictive role of tissue and liquid biomarkers in ES-SCLC patients receiving ICIs. We assessed latest results in terms of predictive and prognostic value of gene expression profiling in SCLC. Finally, we explored the role of liquid biopsy as a tool to monitor SCLC patients over time.

Clinical and molecular characterization of long-term survivors with extensive-stage small cell lung cancer treated with first-line atezolizumab plus carboplatin and etoposide

OBJECTIVES

In the Phase I/III IMpower133 study, first-line atezolizumab plus carboplatin and etoposide (CP/ET) treatment for extensive-stage small cell lung cancer (ES-SCLC) significantly improved overall survival (OS) and progression-free survival versus placebo plus CP/ET. We explored patient and disease characteristics associated with long-term survival in IMpower133, and associations of differential gene expression and SCLC-A (ASCL1-driven), SCLC-N (NEUROD1-driven), SCLC-P (POU2F3-driven), and SCLC-inflamed (SCLC-I) transcriptional subtypes with long-term survival.

MATERIALS AND METHODS

Patients with previously untreated ES-SCLC were randomized 1:1 to four 21-day cycles of CP/ET with atezolizumab or placebo. Long-term survivors (LTS) were defined as patients who lived ≥ 18 months post randomization. A generalized linear model was used to evaluate the odds of living ≥ 18 months. Differential gene expression was analyzed using RNA-sequencing data in LTS and non-LTS. OS was assessed by T-effector and B-cell gene signature expression. Distribution of SCLC transcriptional subtypes was assessed in LTS and non-LTS.

RESULTS

More LTS were in the atezolizumab arm (34%) than in the placebo arm (20%). The odds ratio for living ≥ 18 months in the atezolizumab arm versus the placebo arm was 2.1 (P < 0.03). Enhanced immune-related signaling was seen in LTS in both arms. Exploratory OS analyses showed atezolizumab treatment benefit versus placebo across T-effector and B-cell gene signature expression subgroups. A higher proportion of LTS than non-LTS in both arms had the SCLC-I subtype; this difference was particularly pronounced in the atezolizumab arm.

CONCLUSION

These exploratory analyses suggest that long-term survival is more likely with atezolizumab than placebo in ES-SCLC, confirming the treatment benefit of the IMpower133 regimen.

CLINICALTRIAL

gov Identifier: NCT02763579.

Tumor microenvironment-mediated immune profiles and efficacy of anti-PD-L1 antibody plus chemotherapy stratified by DLL3 expression in small-cell lung cancer

BACKGROUND

Delta-like ligand 3 (DLL3) is a therapeutic target in small-cell lung cancer (SCLC). However, how DLL3 expression status affects the tumor microenvironment (TME) and clinical outcomes in SCLC remains unclear.

METHODS

This retrospective study included patients with postoperative limited-stage (LS)-SCLC and extensive-stage (ES)-SCLC treated with platinum and etoposide (PE) plus anti-programmed cell death ligand 1 (PD-L1) antibody. We investigated the relationship of DLL3 expression with TME, mutation status, tumor neoantigens, and immunochemotherapy.

RESULTS

In the LS-SCLC cohort (n = 59), whole-exome sequencing revealed that DLL3High cases had significantly more neoantigens (P = 0.004) and a significantly higher rate of the signature SBS4 associated with smoking (P = 0.02) than DLL3Low cases. Transcriptome analysis in the LS-SCLC cohort revealed that DLL3High cases had significantly suppressed immune-related pathways and dendritic cell (DC) function. SCLC with DLL3High had significantly lower proportions of T cells, macrophages, and DCs than those with DLL3Low. In the ES-SCLC cohort (n = 30), the progression-free survival associated with PE plus anti-PD-L1 antibody was significantly worse in DLL3High cases than in DLL3Low cases (4.7 vs. 7.4 months, P = 0.01).

CONCLUSIONS

Although SCLC with DLL3High had a higher neoantigen load, these tumors were resistant to immunochemotherapy due to suppressed tumor immunity by inhibiting antigen-presenting functions.

Design and Rationale for a Phase II/III, Randomized, Double-Blind, Placebo-Controlled Study of Sugemalimab as Consolidation Therapy in Patients With Limited-Stage Small-Cell Lung Cancer Who Have Not Progressed Following Concurrent or Sequential Chemoradiotherapy: The SURPASS Study

BACKGROUND

There is still a substantial need of more treatment options for patients with limited-stage small cell lung cancer (LS-SCLC). The standard therapy for LS-SCLC is platinum-based doublet chemotherapy administered concurrently with thoracic radiotherapy (cCRT). In China, sequential chemoradiotherapy (sCRT) is also a common practice. However, the disease inevitably progresses in most patients despite the curative intent and initial response.

MATERIALS AND METHODS

Sugemalimab is an anti-programmed death ligand-1 (PD-L1) antibody that improved clinical outcomes for patients with stage III non-small cell lung cancer after cCRT or sCRT. The SUPPASS study is a phase II/III, randomized, double-blind, placebo-controlled, multicenter study (NCT05623267) that aims to investigate the efficacy and tolerability of sugemalimab as consolidation therapy in patients with LS-SCLC who have no progression following cCRT or sCRT. Approximately 346 patients will be randomized in a 1:1 ratio to receive sugemalimab 1200 mg or placebo every 3 weeks for up to 12 months. The primary endpoint is progression-free survival (PFS). Key secondary endpoints include overall survival (OS), landmark PFS rate, landmark OS rate, objective response rate and safety. Longitudinal molecular residual disease (MRD) testing will be performed as preplanned exploratory analysis.

CONCLUSION

Study results will help demonstrate the efficacy and tolerability of anti-PD-L1 antibody consolidation therapy in LS-SCLC patients who have not progressed following cCRT or sCRT, and help determine the clinical implications of MRD in LS-SCLC.

Outcomes of extensive stage extrapulmonary small cell cancer

BACKGROUND

Extrapulmonary small cell cancer (EPSCC) is a rare malignancy with an incidence of approximately 0.1%-0.4% of all cancers. Treatment of this disease is often based on small cell lung cancer.

AIMS

We aimed to investigate real-world clinical outcomes of patients with extensive-stage (ES) ESPCC.

METHODS

Patients diagnosed with ES EPSCC between 2010 and 2020 from multiple centres in New South Wales were identified. Patient, disease and treatment characteristics were collected and presented using descriptive statistics. Survival was analysed using the Kaplan-Meier method. Univariate and multivariate Cox regression hazard models were used to identify potential prognostic factors.

RESULTS

Sixty eligible ES EPSCC patients were identified, including 65% male and 35% female. The mean age was 69 years (range 37-88). Forty-five per cent were never smokers, 42% ex-smokers and 13% current smokers, and 17% of patients had limited-stage disease prior to development of ES disease. The most common primary sites were genitourinary (42%; mainly prostate (n = 14) and bladder (n = 10)), gastrointestinal (28%; mainly oesophagus (n = 5) and colon (n = 4)) and unknown primary (22%). Treatments received included palliative chemotherapy (67%), palliative radiotherapy (53%), palliative surgery (13%) and best supportive care alone (13%). The median overall survival (OS) was 8.0 months. The median progression-free survival was 5.4 months, and response rate to first-line chemotherapy was 65%. Platinum-based chemotherapy was prognostic of longer OS (HR 0.27, CI 0.12-0.60, P = 0.001).

CONCLUSIONS

Patients with ES EPSCC had good response to palliative chemotherapy, but OS remained poor. Further research is required to improve the prognosis in this population.

Thoracic Radiotherapy in Extensive Disease Small Cell Lung Cancer: Multicenter Prospective Observational TRENDS Study

(1) Introduction: Small cell lung cancer (SCLC) is an aggressive tumor type, accounting for about 15% of all lung cancers. Radiotherapy (RT) plays a fundamental role in both early and advanced stages. Currently, in advanced disease, the use of consolidative chest RT should be recommended for patients with good response to platinum-based first-line chemotherapy, but its use has not yet been standardized. The present prospective study aims to evaluate the pattern of care of consolidative chest RT in patients with advanced stage SCLC, and its effectiveness in terms of disease control and tolerability. (2) Materials and methods: This study was a multicenter prospective observational trial, proposed and conducted within the AIRO lung study group to evaluate the pattern of care of consolidative chest RT after first-line chemotherapy in patients with advanced SCLC. The patient and tumor characteristics, doses, fractionation and volumes of thoracic RT and prophylactic cranial irradiation (PCI), as well as the thoracic and extrathoracic response to the treatment, toxicity and clinical outcomes, were collected and analyzed. (3) Results: From January 2017 to December 2019, sixty-four patients were enrolled. Median follow-up was 33 months. The median age was 68 years (range 42-81); 38 patients (59%) were male and 26 (41%) female. Carboplatin + etoposide for 6 cycles was the most commonly used first-line therapeutic scheme (42%). With regard to consolidative chest RT, 56% of patients (35) received 30 Gy in 10 factions and 16 patients (26%) received 45 Gy in 15 sessions. The modulated intensity technique was used in 84.5% of cases, and post-chemotherapy macroscopic residual disease was the target volume in 87.5% of patients. Forty-four patients (69%) also underwent PCI. At the last follow-up, over 60% of patients did not experience chest disease progression, while 67% showed extrathoracic progression. At the first radiological evaluation after RT, complete response and stable disease were recorded in 6% and 46% of the cases, respectively. Two patients had a long-term complete response to the combined treatment. The brain was the first site of extrathoracic progression in 28%. 1y and 2y OS and PFS were 67%, 19%, 28% and 6%, respectively. Consolidative chest RT was well-tolerated in the majority of patients; it was interrupted in three cases (due to G2 pulmonary toxicity, disease progression and clinical decay, respectively). Only 1 patient developed G3 asthenia. (4) Conclusions: Consolidative chest RT has been shown to be useful in reducing the risk of thoracic disease progression and is absolutely well-tolerated in patients with advanced stage SCLC with good response after first-line chemotherapy. Among the Italian centers that participated in this study, there is still variability in the choice of fractionation and target volumes, although the guidelines contain clear recommendations. The aim of future research should be to clarify the role and modalities of chest RT in the era of immunotherapy in advanced-stage SCLC.

Evolving role of immunotherapy in small cell lung cancer

Small cell lung cancer (SCLC) is a highly lethal subtype of lung cancer with a particularly poor prognosis. For decades, the best available systemic therapy was platinum plus etoposide chemotherapy, which offered frequent but transient responses. Survival gains were finally realized with the addition of immune checkpoint inhibitors to first-line chemotherapy. The phase III IMpower 133 trial showed that the addition of atezolizumab to chemotherapy improved survival. The subsequent CASPIAN trial demonstrated a similar benefit with durvalumab. These results quickly established chemo-immunotherapy as the preferred initial treatment for advanced SCLC, but outcomes remain poor for most patients. Here, we review the current and evolving role of immunotherapy in SCLC and outline emerging strategies poised to further elevate the standard of care.

Brief Report: Exploratory analysis of maintenance therapy in patients with extensive-stage small cell lung cancer treated first-line with atezolizumab plus carboplatin and etoposide

INTRODUCTION

In the Phase I/III IMpower133 study, atezolizumab plus carboplatin and etoposide (CP/ET) followed by maintenance atezolizumab for first-line treatment of extensive-stage small-cell lung cancer (ES-SCLC) led to significant improvement in both overall survival (OS) and progression-free survival (PFS) versus placebo plus CP/ET followed by maintenance placebo. We explored the benefit of atezolizumab versus placebo in the subset of patients who reached the IMpower133 maintenance phase as well as the safety profile of maintenance therapy.

METHODS

Patients with untreated ES-SCLC were randomized 1:1 to four 21-day cycles of CP/ET with atezolizumab or placebo, followed by maintenance atezolizumab or placebo. The primary endpoints were OS and investigator-assessed PFS. A multivariate Cox model from the start of maintenance treatment was used to evaluate the treatment effect and account for lead-time bias; a generalized linear model was used to identify prognostic or predictive characteristics for reaching the maintenance phase.

RESULTS

A similar proportion of patients in each arm received at least the first dose of maintenance therapy (atezolizumab: 77%, n=154/201; placebo: 81%, n=164/202) and were included in the maintenance analysis population. An ECOG performance status of 0 and absence of liver metastases at baseline were identified as prognostic factors for reaching the maintenance phase. The positive treatment effect with atezolizumab remained after adjusting for baseline characteristics. Median OS and PFS from the start of maintenance therapy in the atezolizumab versus placebo arm was 12.5 versus 8.4 months (hazard ratio [HR], 0.59; 95% CI: 0.43-0.80) and 2.6 versus 1.8 months (HR, 0.63 [95% CI: 0.49-0.80]), respectively. Treatment-related adverse events (TRAEs) from the start of maintenance therapy occurred in 41% (n=64/155) and 25% (n=41/163) of safety-evaluable patients in the atezolizumab and placebo arms, respectively, and were grade 3/4 in 28% (n=43/155) and 23% (n=37/163) of the respective populations; no patient in the atezolizumab arm and one patient in the placebo arm had a grade 5 TRAE.

CONCLUSIONS

These data in the context of other immunotherapy trials in ES-SCLC suggest that induction with atezolizumab plus CP/ET as well as maintenance treatment with atezolizumab are important components that contributed to the OS benefit observed in IMpower133. Safety results from randomization and from the start of maintenance therapy were similar between the treatment arms despite the continuation of atezolizumab in the maintenance phase.

Durvalumab, with or without tremelimumab, plus platinum-etoposide in first-line treatment of extensive-stage small-cell lung cancer: 3-year overall survival update from CASPIAN

Background

In the phase III CASPIAN study, first-line durvalumab in combination with etoposide plus either cisplatin or carboplatin (EP) significantly improved overall survival (OS) versus EP alone in extensive-stage small-cell lung cancer (ES-SCLC). Durvalumab plus tremelimumab plus EP numerically improved OS versus EP, but did not reach statistical significance. Here we report updated OS in censored patients after median follow-up of >3 years.

Patients and methods

805 patients with treatment-naïve ES-SCLC were randomized 1 : 1 : 1 to durvalumab plus EP, durvalumab plus tremelimumab plus EP, or EP. The two primary endpoints were OS for durvalumab plus EP versus EP and for durvalumab plus tremelimumab plus EP versus EP.

Results

As of 22 March 2021 (median follow-up 39.4 months, 86% maturity), durvalumab plus EP continued to demonstrate improved OS versus EP: hazard ratio (HR) 0.71 [95% confidence interval (CI) 0.60-0.86; nominal P = 0.0003]; median OS was 12.9 versus 10.5 months, and 36-month OS rate was 17.6% versus 5.8%. Durvalumab plus tremelimumab plus EP continued to numerically improve OS versus EP: HR 0.81 (95% CI: 0.67-0.97; nominal P = 0.0200); median OS was 10.4 months, and 36-month OS rate was 15.3%. Twenty-seven and nineteen patients in the durvalumab plus EP and durvalumab plus tremelimumab plus EP arms, respectively, remained on durvalumab treatment at data cut-off.

Conclusions

Three times more patients were estimated to be alive at 3 years when treated with durvalumab plus EP versus EP, with the majority still receiving durvalumab at data cut-off, further establishing durvalumab plus EP as first-line standard of care for ES-SCLC.

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Durvalumab plus EP showed sustained OS benefit over EP with a well-tolerated safety profile after median follow-up >3 years.

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Three times more patients were estimated to be alive at 3 years when treated with durvalumab plus EP versus EP alone.

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These results further establish durvalumab plus EP as standard of care for first-line treatment of patients with ES-SCLC.

Extensive-Stage Small-Cell Lung Cancer: First-Line and Second-Line Treatment Options

Extensive-stage small-cell lung cancer is a therapeutically challenging disease. After more than two decades without clinical progress, the addition of programmed cell death protein 1 axis blockade to platinum-based chemotherapy has demonstrated sustained overall survival benefit and represents the current standard of care in the first-line setting. Despite this benefit, resistance emerges relatively rapidly in virtually all patients. Although newer treatments are being incorporated in the relapse setting, marked therapeutic resistance is typically observed in patients with relapsed small-cell lung cancer (SCLC), underscoring the need of developing more effective therapies in this setting. Notably, recent progress in the understanding of the molecular biology of SCLC might bring possibilities toward molecularly informed therapeutic strategies for patients with SCLC, which could have a significant impact for improving outcomes in this disease. Here, we review current treatment options and recent progress made in the first-line and relapsed SCLC, including the role of biomarkers and new evolving therapeutic strategies.

Current state of the art and future perspectives with immunotherapy in the management of small cell lung cancer

INTRODUCTION

Small cell lung cancer (SCLC) is an aggressive tumor with a severe prognosis. At the time of diagnosis, most patients present with extensive-stage (ES) disease. For decades, platinum-based chemotherapy has been the only pillar of SCLC treatment, but now, the clinical management of this disease is rapidly evolving thanks to the introduction of immune checkpoint inhibitors (ICIs).

AREAS COVERED

In this review, we describe the most recent advances in the treatment of SCLC and discuss the emerging challenges associated with ICI treatments. Meaningful data were collected from the currently available literature on PubMed and in international oncology meetings.

EXPERT OPINION

Recently, meaningful improvements in outcomes of SCLC patients have been achieved with anti-PD-L1 atezolizumab or durvalumab combined with chemotherapy in first line. Results of studies evaluating the role of ICIs in limited-stage (LS) SCLC patients are awaited. Further efforts are required to better understand the role of immunotherapy in the treatment of SCLC and to identify patients most likely to benefit from this treatment strategy.

Recent developments in the treatment of small cell lung cancer

Small cell lung cancer (SCLC) comprises about 15% of all lung cancers. It is an aggressive disease, with early metastasis and a poor prognosis. Until recently, SCLC treatment remained relatively unchanged, with chemotherapy remaining the cornerstone of treatment. In this overview we will highlight the recent advances in the field of staging, surgery, radiotherapy and systemic treatment. Nevertheless, the prognosis remains dismal and there is a pressing need for new treatment options. We describe the progress that has been made in systemic treatment by repurposing existing drugs and the addition of targeted treatment. In recent years, immunotherapy entered the clinic with high expectations of its role in the treatment of SCLC. Unravelling of the genomic sequence revealed new possible targets that may act as biomarkers in future treatment of patients with SCLC. Hopefully, in the near future, we will be able to identify patients who may benefit from targeted therapy or immunotherapy to improve prognoses.

Gene Amplification-Associated Overexpression of the Selenoprotein tRNA Enzyme TRIT1 Confers Sensitivity to Arsenic Trioxide in Small-Cell Lung Cancer

The alteration of RNA modification patterns is emerging as a common feature of human malignancies. If these changes affect key RNA molecules for mRNA translation, such as transfer RNA, they can have important consequences for cell transformation. TRIT1 is the enzyme responsible for the hypermodification of adenosine 37 in the anticodon region of human tRNAs containing serine and selenocysteine. Herein, we show that TRIT1 undergoes gene amplification-associated overexpression in cancer cell lines and primary samples of small-cell lung cancer. From growth and functional standpoints, the induced depletion of TRIT1 expression in amplified cells reduces their tumorigenic potential and downregulates the selenoprotein transcripts. We observed that TRIT1-amplified cells are sensitive to arsenic trioxide, a compound that regulates selenoproteins, whereas reduction of TRIT1 levels confers loss of sensitivity to the drug. Overall, our results indicate a role for TRIT1 as a small-cell lung cancer-relevant gene that, when undergoing gene amplification-associated activation, can be targeted with the differentiation agent arsenic trioxide.

Small cell lung cancer: a slightly less orphan disease after immunotherapy

Small cell lung cancer (SCLC) is an aggressive malignancy accounting for 15% of all diagnosed cases of lung cancer. After >15 years without any clinically relevant therapeutic advances, extensive-disease SCLC has become the second thoracic malignancy for which immune checkpoint inhibitors (ICIs) have shifted the treatment paradigm to improve overall survival. Today, atezolizumab or durvalumab in combination with platinum-etoposide chemotherapy is considered the new standard of care in the first-line setting in SCLC. However, the magnitude of benefit with this immune-chemotherapy strategy in SCLC is more modest than that observed in metastatic non-small-cell lung cancer patients. The immunosuppressive phenotype of SCLC plays an important role in hampering ICI efficacy and may explain the differences in outcomes between these two types of lung cancer. In this review, we provide a summary of recent therapeutic advances in SCLC in light of ICIs, as well as current challenges of this strategy in patients who are elderly, have poor performance status or brain metastases. We also address future perspectives of immunotherapeutic strategies currently in clinical development for these patients.

Liquid Biopsy in Small Cell Lung Cancer-A Route to Improved Clinical Care?

Small cell lung cancer (SCLC) has a particularly poor prognosis despite the high initial response to first-line systemic therapy, and there is a well-recognised lack of meaningful treatments beyond the second line. A number of reasons have been put forward to explain this, including a lack of common, easily-druggable genetic mutations in SCLC and rarity of high-quality tissue samples due to late presentation. Liquid biopsies, including circulating tumour cells (CTCs) and circulating tumour DNA (ctDNA) are increasingly used as surrogates for tumour tissue and have the advantage of being easily obtained serially to inform on the biology of disease progression and acquired chemoresistance, and may provide a pathway to improve care in this notoriously refractory disease. Here we discuss the current evidence behind these liquid biopsy methods in SCLC, and how they could be employed in future clinical care.

Advances and Therapeutic Perspectives in Extended-Stage Small-Cell Lung Cancer

Extended small cell lung cancer (ED-SCLC) is a very aggressive disease, characterized by rapid growth and an early tendency to relapse. In contrast to non-small cell lung cancer, no therapeutic innovation has improved survival in patients with ED-SCLC over the past 20 years. Recently, immunotherapy has shown an important role in the management of these patients, emerging as the treatment of first choice in combination with chemotherapy and completely changing the therapeutic paradigm. However, patients' selection for this strategy is still challenging due to a lack of reliable predictive biomarkers. Conversely, the immunotherapy efficacy beyond the first line is pretty disappointing and innovative chemotherapies or target agents seem to be more promising in this setting. Some of them are also under evaluation as an upfront strategy and they will probably change the treatment algorithm in the next future. This proposal provides a comprehensive overview of available treatment strategies for ED-SCLC patients, highlighting their strengths and weaknesses.