In-hospital thromboprophylaxis variation and the risk of venous thromboembolism after lung cancer surgery: a nationwide cohort study.

OBJECTIVES: Venous thromboembolic event (VTE) is a severe complication in patients with lung cancer undergoing thoracic surgery. Nevertheless, because of insufficient evidence, there are no clear guidelines, and VTE prophylaxis practices vary widely. This nationwide cohort study was a comparative study investigating VTE risk in surgical departments that routinely administered in-hospital thromboprophylaxis with low-molecular-weight heparin compared to those that did not. METHODS: We identified all patients with non-small-cell lung cancer (NSCLC) who underwent surgery in Denmark during 2010-2021. Thoracic surgery was exclusively performed in the 4 university hospitals. Three hospitals implemented in-hospital thromboprophylaxis as standard care since 2000, while the fourth adopted this practice in September 2016. VTE events were assessed at 6-month follow-up according to hospital and study period, using an inverse probability of treatment weighting approach. RESULTS: We identified 9615 patients. During 6-month follow-up, a total of 190 VTE events were observed, resulting in a weighted rate of 4.5 events per 100 person-years and an absolute risk of 2.2%. There was no clear trend according to hospital site or use of in-hospital thromboprophylaxis with a 2.2% risk in the hospital not using thromboprophylaxis compared to 1.7-3.1% in those that did. CONCLUSIONS: Use of in-hospital thromboprophylaxis did not affect the risk of VTE after surgery for NSCLC, suggesting that relying solely on in-hospital thromboprophylaxis may be insufficient to mitigate VTE risk in these patients. Further research is warranted to investigate the potential benefits of extended thromboprophylaxis in reducing VTE risk in selected NSCLC surgical patients.

Risk of Venous Thromboembolism in Patients With Stage III and IV Non-Small-Cell Lung Cancer: Nationwide Descriptive Cohort Study.

BACKGROUND: Venous thromboembolism (VTE) is a common complication in patients starting cancer therapies for non-small-cell lung cancer (NSCLC). We examined the risk and timing of VTE in patients with stage IIIA, IIIB to C, and stage IV NSCLC according to received cancer treatments. MATERIALS AND METHODS: A nationwide registry-based cohort study of patients recorded in the Danish Lung Cancer Registry (2010-2021) followed for 1 year after entry into the registry to assess the incidence of VTE. The Aalen-Johansen estimator was used to calculate the risk of VTE after treatment commencement with chemotherapy, radiotherapy, chemoradiation, immunotherapy, and targeted therapy. RESULTS: Among the 3475 patients with stage IIIA, 4047 with stage IIIB to C, and 18,082 patients with stage IV cancer, the 1-year risk of VTE was highest in the first 6 months and varied markedly by cancer stage and cancer treatment. In stage IIIA, VTE risk was highest with chemotherapy (3.9%) and chemoradiation (4.1%). In stage IIIB to C, risks increased with chemotherapy (5.2%), immunotherapy (9.4%), and targeted therapy (6.0%). Stage IV NSCLC showed high risk with targeted therapy (12.5%) and immunotherapy (12.2%). The risk was consistently higher for pulmonary embolism than deep vein thrombosis. CONCLUSION: VTE risks vary substantially according to cancer treatments and cancer stages. The highest risk was observed in the initial 6 months of therapy initiation. These insights emphasize the need for tailored risk assessment and vigilance in managing VTE complications in patients with NSCLC. Further research is needed to optimize individual thromboprophylaxis strategies for patients with unresectable and metastatic NSCLC.

Performance characteristics of a polymerase chain reaction-based assay for the detection of EGFR mutations in plasma cell-free DNA from patients with non-small cell lung cancer using cell-free DNA collection tubes.

Survival rates in non-small cell lung cancer (NSCLC) are low. Detection of circulating tumor DNA in liquid biopsy (plasma) is increasingly used to identify targeted therapies for clinically actionable mutations, including EGFR mutations in NSCLC. The cobas® EGFR Mutation Test v2 (cobas EGFR test) is FDA-approved for EGFR mutation detection in tissue or liquid biopsy from NSCLC. Standard K2EDTA tubes require plasma separation from blood within 4 to 8 hours; however, Roche Cell-Free DNA (cfDNA) Collection Tubes (Roche cfDNA tube) enable whole blood stability for up to 7 days prior to plasma separation. This analysis assessed performance of Roche cfDNA tubes with the cobas EGFR test for the detection of EGFR mutations in plasma from healthy donors or patients with NSCLC. Overall, test performance was equally robust with either blood collection tube, eg, regarding limit of detection, linearity, and reproducibility, making Roche cfDNA tubes suitable for routine clinical laboratory use in this setting. Importantly, the Roche cfDNA tubes provided more flexibility for specimen handling versus K2EDTA tubes, eg, in terms of tube mixing, plasma separation, and sample stability, and do not require processing of blood within 8 hours thereby increasing the reach of plasma biopsies in NSCLC.

ctDNA-based minimal residual disease detection in lung cancer patients treated with curative intended chemoradiotherapy using a clinically transferable approach.

BACKGROUND: Reliable biomarkers are needed to identify tumor recurrence of non-small cell lung cancer (NSCLC) patients after chemoradiotherapy (CRT) with curative intent. This could improve consolidation therapy of progressing patients. However, the approach of existing studies has limited transferability to the clinic. MATERIALS AND METHODS: A retrospective analysis of 135 plasma samples from 56 inoperable NSCLC patients who received CRT with curative intent was performed. Plasma samples collected at baseline, at the first check-up (average 1.6 months post-RT), and at the second check-up (average 4.5 months post-RT) were analyzed by deep sequencing with a commercially available cancer personalized profiling strategy (CAPP-Seq) using a tumor-agnostic approach. RESULTS: Detection of circulating tumor DNA (ctDNA) at 4.5 months after therapy was significantly associated with higher odds of tumor recurrence (OR: 5.4 (CI: 1.1-31), Fisher's exact test: p-value = 0.022), and shorter recurrence-free survival (RFS) (HR: 4.1 (CI: 1.7-10); log-rank test: p-value = 9e-04). In contrast, detection of ctDNA at 1.6 months after therapy was not associated with higher odds of tumor recurrence (OR: 2.7 (CI: 0.67-12), Fisher's exact test: p-value = 0.13) or shorter RFS (HR: 1.5 (CI: 0.67-3.3); log-rank test: p-value = 0.32). CONCLUSION: This study demonstrates that the detection of ctDNA can be used to identify minimal residual disease 4.5 months after CRT in NSCLC patients using a commercially available kit and a tumor-agnostic approach. Furthermore, the time point of collecting the plasma sample after CRT has decisive importance for the prognostic value of ctDNA. MICRO ABSTRACT: This study analysed 135 plasma samples from 56 NSCLC patients treated with curative intent chemoradiotherapy using a tumor-agnostic approach. Detecting ctDNA at 4.5 months post-treatment was linked to higher recurrence odds, indicating ctDNA's potential as a biomarker for identifying residual disease after treatment with curative intent. Importantly, the study emphasizes the importance of timing for accurate ctDNA analysis results.

Integration of Cell-Free DNA End Motifs and Fragment Lengths Can Identify Active Genes in Liquid Biopsies.

Multiple studies have shown that cell-free DNA (cfDNA) from cancer patients differ in both fragment length and fragment end motif (FEM) from healthy individuals, yet there is a lack of understanding of how the two factors combined are associated with cancer and gene transcription. In this study, we conducted cfDNA fragmentomics evaluations using plasma from lung cancer patients (n = 12) and healthy individuals (n = 7). A personal gene expression profile was established from plasma using H3K36me3 cell-free chromatin immunoprecipitation sequencing (cfChIP-seq). The genes with the highest expression displayed an enrichment of short cfDNA fragments (median = 19.99%, IQR: 16.94-27.13%, p < 0.0001) compared to the genes with low expression. Furthermore, distinct GC-rich FEMs were enriched after cfChIP. Combining the frequency of short cfDNA fragments with the presence of distinct FEMs resulted in an even further enrichment of the most expressed genes (median = 37.85%, IQR: 30.10-39.49%, p < 0.0001). An in vitro size selection of <150 bp cfDNA could isolate cfDNA representing active genes and the size-selection enrichment correlated with the cfChIP-seq enrichment (Spearman r range: 0.499-0.882, p < 0.0001). This study expands the knowledge regarding cfDNA fragmentomics and sheds new light on how gene activity is associated with both cfDNA fragment lengths and distinct FEMs.

Risk and Timing of Venous Thromboembolism After Surgery for Lung Cancer: A Nationwide Cohort Study.

BACKGROUND: Venous thromboembolism (VTE) is a potentially preventable serious complication in patients with lung cancer undergoing thoracic operation. We examined the risk and timing of VTE after surgery for primary non-small cell lung cancer (NSCLC). METHODS: All patients undergoing operation for NSCLC in Denmark between 2003 and 2021 were identified in the Danish Lung Cancer Registry. VTE events in the year after operation were assessed by stage, patient characteristics, and surgical procedure. RESULTS: We identified 13,197 patients who underwent operation for NSCLC in 2003 to 2021 (mean age, 67.6 years; 50% female); 10,524 (79.7%) had stage I-II NSCLC, and 2673 (20.3%) had stage III-IV. During 1-year follow-up, there were 335 VTE events, yielding a rate of 2.87 events/100 person-years and an absolute risk of 3.3% (95% CI, 2.3-4.0). VTE risk increased with advancing cancer stage (1.8% for stage I vs 3.9% for stage IV) but varied little by pathologic type, sex, and comorbidity level. Bilobectomy was associated with highest VTE risk (4.8%; 95% CI, 3.2-6.9), followed by pneumonectomy (3.5%; 95% CI, 2.3-5.0). The hazard of VTE was highest during the first 3 months after operation, after which it declined. For stage IV cancer, hazards increased again after 6 months. At 1 year, all-cause death was 12.6% (95% CI, 12.0%-13.1%). CONCLUSIONS: VTE developed in 3.3% of patients undergoing operation for NSCLC, most commonly within 3 months postoperatively. Prolonged thromboprophylaxis could be considered, particularly in those with advanced cancer stage and undergoing extended resections.

Plasma Immune Proteins and Circulating Tumor DNA Predict the Clinical Outcome for Non-Small-Cell Lung Cancer Treated with an Immune Checkpoint Inhibitor.

Immunotherapy has altered the therapeutic landscape for patients with non-small-cell lung cancer (NSCLC). The immune checkpoint inhibitor pembrolizumab targets the PD-1/PD-L1 signaling axis and produces durable clinical responses, but reliable biomarkers are lacking. Using 115 plasma samples from 42 pembrolizumab-treated patients with NSCLC, we were able to identify predictive biomarkers. In the plasma samples, we quantified the level of 92 proteins using the Olink proximity extension assay and circulating tumor DNA (ctDNA) using targeted next-generation sequencing. Patients with an above-median progression-free survival (PFS) had significantly higher expressions of Fas ligand (FASLG) and inducible T-cell co-stimulator ligand (ICOSLG) at baseline than patients with a PFS below the median. A Kaplan-Meier analysis demonstrated that high levels of FASLG and ICOSLG were predictive of longer PFS and overall survival (OS) (PFS: 10.83 vs. 4.49 months, OS: 27.13 vs. 18.0 months). Furthermore, we identified a subgroup with high expressions of FASLG and ICOSLG who also had no detectable ctDNA mutations after treatment initiation. This subgroup had significantly longer PFS and OS rates compared to the rest of the patients (PFS: 25.71 vs. 4.52 months, OS: 34.62 vs. 18.0 months). These findings suggest that the expressions of FASLG and ICOSLG at baseline and the absence of ctDNA mutations after the start of treatment have the potential to predict clinical outcomes.

Diagnostic Workup, Treatment Patterns, and Clinical Outcomes in Early-Stage IB-IIIA Non-Small-Cell Lung Cancer Patients in Denmark.

Despite recent improvements in early-stage non-small-cell lung cancer (NSCLC), disease relapse remains challenging. Moreover, real-world evidence on long-term follow-up of disease-free survival (DFS) and recurrence patterns in a large, unselected cohort of early-stage NSCLC patients is lacking. This cohort study aimed to assess clinical characteristics, diagnostic workup, treatment, survival, and risk of disease relapse among early-stage NSCLC patients. Adult patients with stage IB, II, or IIIA NSCLC diagnosed and/or treated at Aarhus University Hospital in Denmark from January 2010 to December 2020 were included and followed-up until May 2021. Comprehensive clinical data were collected from electronic medical records of eligible patients and linked to Danish register data. The study population comprised 1341 early-stage NSCLC patients: 22%, 40%, and 38% were diagnosed with stage IB, II, and IIIA disease, respectively. In total, 42% of patients were tested for epidermal growth factor receptor (EGFR), of whom 10% were EGFR-mutation-positive (EGFRm+). Half of all patients received surgery, and nine percent of patients received stereotactic body radiation therapy (SBRT). Disease-free survival 5 years post-diagnosis was 49%, 42%, and 22% for stage IB, II, and stage IIIA patients, respectively. DFS improved over time both for patients treated with surgery and SBRT. However, disease relapse remained a challenge, with approximately 40% of stage IIIA having relapsed 3 years post-diagnosis. This study contributes important knowledge that puts clinical trials on new perioperative treatment modalities for early-stage NSCLC patients into perspective. Our findings cover an essential evidence gap on real-world DFS and recurrence dynamics, confirming that despite an improvement in DFS over time and across different treatment modalities, disease relapse remains a monumental challenge. Therefore, better treatment strategies are needed.

Clinical outcomes of ALK+ non-small cell lung cancer in Denmark.

BACKGROUND: Real-world clinical outcomes of anaplastic lymphoma kinase positive (ALK+) non-small cell lung cancer (NSCLC) patients vary. This study aimed to investigate the treatment and clinical outcomes of all ALK+ NSCLC patients in Denmark in the period 2011-2018, regardless of disease stage. MATERIALS AND METHODS: A national pathology database with complete coverage was used to identify ALK+ NSCLC patients diagnosed between 2011 and 2018. Clinical data were obtained through retrospective chart reviews. Overall survival (OS) and duration of treatment (DOT) were analyzed using Kaplan-Meier methodologies. RESULTS: A total of 209 ALK+ NSCLC patients were included. The cohort had a slight overrepresentation of female patients (56.5%) with a mean age of 61.6 years. Most patients were adenocarcinoma cases (97%) and presented with an ECOG performance status of 0-1 (79%). Stage IIIb-IVb patients comprised 70% of the cohort. The use of ALK-tyrosine kinase inhibitors (TKIs) as first-line treatment increased over time, with the 1st generation ALK-TKI crizotinib being the predominant treatment in the 1st line. In 1st line treatment, 2nd generation ALK-TKIs had a median DOT more than twice the median DOT of crizotinib (25.1 and 9.1 months, respectively). The median OS for the entire cohort was 44.0 months. Patients with stage I-IIIA disease had a median OS that had not been reached, while those with stage IIIb-IVb disease had a median OS of 31.8 months. Patients with stage IIIb-IVb disease receiving an ALK-TKI as 1st line treatment had a median OS of 42.5 months with immature follow-up. Brain metastases at diagnosis or choice of 1st line treatment did not statistically significantly impact OS. CONCLUSION: This study gives insights into the treatment and outcome of ALK+ NSCLC patients in Denmark and provides a real-world confirmation of the superior disease control provided by 2nd generation ALK-TKIs as compared to the 1st generation ALK-TKI crizotinib.

Improved overall survival for Stage III NSCLC patients treated with curative-intended therapy from 2010 to 2018-a cohort study in Denmark.

BACKGROUND: Despite advances in treatment strategies and improved clinical outcomes, an unmet need remains for NSCLC patients. With an increased real-world knowledge of NSCLC, clinicians could offer patients optimal tailored treatment and disease management. In this retrospective cohort study, we describe patient characteristics, treatment patterns and modality, and survival in NSCLC patients diagnosed and treated at Aarhus University Hospital, Denmark. METHODS: Data on Stage III NSCLC patients aged ≥18 years diagnosed 2010-2018 were obtained from a regional cancer database and linked to national registries for information on socioeconomic and vital status. Patients were stratified by planned treatment intention at diagnosis (curative/palliative). Treatment patterns and overall survival (OS) were estimated using time-to-event methods. RESULTS: Broad patient and diseases characteristics and multiple treatment options demonstrated the heterogeneity of this patient cohort. Of 851 Stage III NSCLC patients, 599 (70%) and 252 (30%) were offered curative- and palliative-intended treatment, respectively, upon evaluation by a multidisciplinary team (MDT). The most frequent treatment modalities were CRT (n = 328; 55%) and RT (n = 97; 38%) in the curative and palliative setting, respectively. Age, disease stage, performance status and comorbidity were associated with curative-intended treatment initiation. Curative-intended treatment was associated with an improved OS of 14.6 months (median OS 24.4 months, 95% CI 21.1-27.6). Being offered curative-intended treatment and/or being diagnosed in the more contemporary study period (2016-2018) were significantly correlated with better OS (p < 0.001). CONCLUSION: Stage III NSCLC is a heterogeneous disease as regards patient and clinical characteristics, multiple treatment options, and outcomes. Age, disease staging, performance status, and comorbidity, as well as MDT evaluation and matching treatment intent, are important determinants of curative-intended treatment. Notably, an NSCLC diagnosis in the more contemporary study period was statistically significantly associated with better OS.

Blood tumor mutational burden and dynamic changes in circulating tumor DNA predict response to pembrolizumab treatment in advanced non-small cell lung cancer.

Background: The use of immunotherapy targeting the programmed cell death protein-1 (PD-1) and its ligand (PD-L1) has provided new hope for patients with non-small cell lung cancer (NSCLC). However, good biomarkers are needed to identify which patients will benefit from the treatment. In this study, we investigated if circulating tumor DNA (ctDNA) could predict response to pembrolizumab. Methods: Plasma samples from patients with NSCLC treated with pembrolizumab were collected immediately before and after one or two cycles of treatment. ctDNA was isolated and analyzed using targeted next-generation sequencing with a lung cancer gene panel. Results: Mutations were detected in ctDNA in 83.93% of patients before treatment initiation. High blood tumor mutational burden (bTMB), measured as the number of different mutations per Mb panel, correlated to longer progression-free survival (PFS) (10.45 vs. 2.30 months) and overall survival (OS) (21.80 vs. 12.20 months), whereas no predictive value was found in the number of mutant molecules per mL of plasma. The absence of mutations just after treatment initiation correlated with improved PFS (20.25 vs. 4.18 months) and OS (28.93 vs. 15.33 months). High bTMB before treatment was associated with a decreasing ctDNA level after treatment initiation. Importantly, a subgroup of patients experienced an increase in the ctDNA level after treatment initiation, and this correlated with inferior PFS (2.19 vs. 11.21 months) and OS (7.76 vs. 24.20 months). All patients in the subgroup with increased ctDNA level progressed within 10 months. Conclusions: Monitoring of ctDNA contains vital information about response to therapy, where the bTMB and the dynamics in the initial part of treatment are particularly important for response. Increasing ctDNA levels after treatment initiation are significantly correlated with inferior survival.

DNAfusion: an R/Bioconductor package for increased sensitivity of detecting gene fusions in liquid biopsies.

BACKGROUND: EML4-ALK gene fusions are oncogenic drivers in non-small cell lung cancer (NSCLC), and liquid biopsies containing EML4-ALK fragments can be used to study tumor dynamics using next-generation sequencing (NGS). However, the sensitivity of EML4-ALK detection varies between pipelines and analysis tools. RESULTS: We developed an R/Bioconductor package, DNAfusion, which can be applied to BAM files generated by commercially available NGS pipelines, such as AVENIO. Forty-eight blood samples from a training cohort consisting of 41 stage IV EML4-ALK-positive NSCLC patients and seven healthy controls were used to develop DNAfusion. DNAfusion detected EML4-ALK in significantly more samples (sensitivity = 61.0%) compared to AVENIO (sensitivity = 36.6%). The newly identified EML4-ALK-positive patients were verified using droplet digital PCR. DNAfusion was subsequently validated in a blinded validation cohort comprising 24 EML4-ALK-positive and 24 EML4-ALK-negative stage IV NSCLC patients. DNAfusion detected significantly more EML4-ALK individuals in the validation cohort (sensitivity = 62.5%) compared to AVENIO (sensitivity = 29.2%). DNAfusion demonstrated a specificity of 100% in both the training and validation cohorts. CONCLUSION: Here we present DNAfusion, which increases the sensitivity of EML4-ALK detection in liquid biopsies and can be implemented downstream of commercially available NGS pipelines. The simplistic method of operating the R package makes it easy to implement in the clinical setting, enabling wider expansion of NGS-based diagnostics.

Circulating immune response proteins predict the outcome following disease progression of osimertinib treated epidermal growth factor receptor-positive non-small cell lung cancer patients.

Background: Lung cancer patients with sensitizing epidermal growth factor receptor (EGFR) mutations treated with osimertinib will eventually develop progressive disease (PD). The survival following PD varies greatly between patients, and no effective treatment strategy has been established. Furthermore, at the moment, no easily accessible and precise biomarker exists that can predict the survival after PD. Methods: We analyzed blood samples drawn from non-small cell lung cancer patients harboring EGFR mutations that were treated with osimertinib. The levels of 92 circulating proteins were analyzed from plasma samples using a proximity extension assay (PEA). The results were evaluated with Gene Ontology (GO) enrichment analysis to reveal patterns of protein expression at progression while on osimertinib treatment. Results: We found that the expression of 7 proteins were significantly altered at PD, compared to a sample taken at osimertinib response. GO enrichment analysis demonstrated that most of the significant proteins were related to the immune system, specifically the adaptive immune response. Defining two groups of patients, based on the levels of circulating immune response proteins at PD, revealed significant differences in the overall survival (OS) after PD [hazard ratio (HR) =3.04; 95% confidence interval (CI): 1.24-7.45; P=0.0046]. Conclusions: In this study, we discover novel circulating biomarkers that can predict the OS after PD on osimertinib. These findings support the recent acknowledgement of the immune system's importance in osimertinib resistance.

Cell-free chromatin immunoprecipitation can determine tumor gene expression in lung cancer patients.

Cell-free DNA (cfDNA) in blood plasma can be bound to nucleosomes that contain post-translational modifications representing the epigenetic profile of the cell of origin. This includes histone H3 lysine 36 trimethylation (H3K36me3), a marker of active transcription. We hypothesised that cell-free chromatin immunoprecipitation (cfChIP) of H3K36me3-modified nucleosomes present in blood plasma can delineate tumour gene expression levels. H3K36me3 cfChIP followed by targeted NGS (cfChIP-seq) was performed on blood plasma samples from non-small-cell lung cancer (NSCLC) patients (NSCLC, n = 8), small-cell lung cancer (SCLC) patients (SCLC, n = 4) and healthy controls (n = 4). H3K36me3 cfChIP-seq demonstrated increased enrichment of mutated alleles compared with normal alleles in plasma from patients with known somatic cancer mutations. Additionally, genes identified to be differentially expressed in SCLC and NSCLC tumours had concordant H3K36me3 cfChIP enrichment profiles in NSCLC (sensitivity = 0.80) and SCLC blood plasma (sensitivity = 0.86). Findings here expand the utility of cfDNA in liquid biopsies to characterise treatment resistance, cancer subtyping and disease progression.

Prognostic value of KRAS mutations, TP53 mutations and PD-L1 expression among lung adenocarcinomas treated with immunotherapy.

AIMS: The aim of this study was to investigate the association between oncogenic alterations and programmed cell death ligand 1 (PD-L1) expression in lung adenocarcinomas, as well as the prognostic value of KRAS and/or TP53 mutations in patients treated with immunotherapy. METHODS: This study is a retrospective cohort study of 519 patients with lung adenocarcinomas analysed for mutations and PD-L1 expression. Data were collected from electronic pathology record system, next-generation sequencing system, and clinical databases. Association between mutations and PD-L1 expression was investigated, as well as survival statistics of the 65 patients treated with immunotherapy. RESULTS: 41% of the samples contained a KRAS mutation, predominantly together with mutations in TP53 (41%) or STK11 (10%). Higher expression of PD-L1 was seen among patients with KRAS mutations (p=0.002) and EGFR wild type (p=0.006). For patients treated with immunotherapy, there was no statistically significant difference for overall survival (OS) and progression-free survival (PFS) according to KRAS mutation status, TP53 mutation status or PD-L1 expression. The HR for concomitant mutations in TP53 and KRAS was 0.78 (95% CI 0.62 to 0.99) for OS and 0.43 (0.21 to 0.88) for PFS. Furthermore, concomitant TP53 and KRAS mutations predicted a better PFS (p=0.015) and OS (p=0.029) compared with no mutations or a single mutation in either TP53 or KRAS. CONCLUSION: Mutations in TP53 together with KRAS may serve as a potential biomarker for survival benefits with immunotherapy.

Molecular epidemiology study of programmed death ligand 1 and ligand 2 protein expression assessed by immunohistochemistry in extensive-stage small-cell lung cancer.

Objectives: Prevalence of tumor PD-L1 expression in extensive-stage small-cell lung cancer (ES-SCLC) is variable, and data on PD-L2 expression are limited. The prognostic values of these biomarkers are not well understood. The current study was conducted to address these data gaps. Methods: A retrospective cohort study of Danish patients with histologically confirmed ES-SCLC and evaluable tumor samples who were receiving usual care before the introduction of immunotherapy was conducted. Protein expression of PD-L1 and PD-L2 was determined by immunohistochemistry (IHC) using the PD-L1 IHC 22C3 pharmDx assay and a PD-L2 IHC assay using a propriety mouse monoclonal antibody. A combined positive score (CPS) of ≥1 was used to define biomarker positivity. Kaplan-Meier plots and Cox proportional hazard models were employed to assess the relationship between PD-L1 and PD-L2 protein expression and OS. Results: Among 80 patients, 31% (n=25) and 36% (n=29) had disease positive for PD-L1 and PD-L2, respectively. Overall, 85% (n=68) of patients had concordant PD-L1/PD-L2 status; 26% (n=21) had double positive disease (both PD-L1 and PD-L2 CPS ≥1) and 59% (n=47) had double negative disease (both PD-L1 and PD-L2 CPS <1). PD-L1 and PD-L2 positivity were each associated with longer OS (unadjusted hazard ratios [HRs], 0.35 [95% CI, 0.21-0.61] and 0.50 [95% CI, 0.31-0.82]); the associations persisted after adjustment for several known prognostic factors (HRs, 0.41 [95% CI, 0.22-0.75] and 0.44 [95% CI, 0.25-0.79] for PD-L1 and PD-L2 positivity, respectively). When evaluating OS in patients with double positive disease, unadjusted and adjusted HRs for double positive compared with double negative were similar to those with only PD-L1 or PD-L2 positivity (unadjusted HR, 0.36 [95% CI, 0.20-0.64]; adjusted HR, 0.36 [0.18-0.73]). Conclusion: PD-L1 and PD-L2 positivity were observed in approximately one-third of assessed ES-SCLC tumor samples and were highly congruent. Patients with PD-L1 and PD-L2 positivity, alone or combined, were associated with longer OS, independent of other prognostic factors.

Tumoral PD-L1 does not impact time to treatment discontinuation in EGFR mutated non-small cell lung cancer patients treated with EGFR tyrosine kinase inhibitor-a Danish cohort study.

Background: Not all non-small cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) mutations respond equally to therapy with tyrosine kinase inhibitors (TKIs). Programmed death ligand-1 (PD-L1) has previously been speculated as a possible biomarker for treatment outcome because of its positive correlation with these mutations in cell lines, but clinical studies have yielded conflicting results. We investigate the predictive potential of this surface protein in relation to clinical benefit in patients as measured by time to treatment discontinuation (TTD). Methods: We screened 516 Danish patients with EGFR mutations for inclusion based on a history of TKI treatment and a PD-L1 status that was assessed no earlier than three months prior to treatment initiation. Patients were stratified according to their expression of the potential biomarker as either negative (0%), low (1-49%) or high (≥50%). We employed the Kaplan-Meier method and the log rank test to test for a difference in treatment duration according to PD-L1 expression. Results: We included 111 Danish patients. The median follow-up time from inclusion until death or censoring at the end of the study was 670 days (range, 32-1,664 days, 95% CI: 502-897 days). Fifty-seven patients (51%) categorized as PD-L1 expression negative, 32 (29%) as low and 22 (20%) as high. We tested for differences in treatment duration between the three groups. Our tests did not yield statistically significant P values. Conclusions: In our cohort of 111 Danish patients with NSCLC harboring mutations in the epidermal growth factor receptor gene, expression levels of PD-L1 did not significantly impact the duration of clinical benefit from tyrosine kinase treatment.

Clinical features affecting efficacy of immune checkpoint inhibitors in pretreated patients with advanced NSCLC: a Danish nationwide real-world study.

BACKGROUND: Immune checkpoint inhibitors (ICIs) are implemented as standard treatment for patients with advanced non-small cell lung cancer (NSCLC) in first-line and subsequent-line treatment. However, certain subgroups such as patients with older age, poor performance status (PS), and severe comorbidity are underrepresented in the randomized controlled trials (RCTs). This study aimed to assess overall survival (OS), treatment data, and clinical features affecting second- or subsequent-line ICI efficacy in an unselected, Danish, nationwide NSCLC population. METHODS: Patients with advanced NSCLC who started nivolumab or pembrolizumab as second-line or subsequent-line treatment between 1 September 2015, and 1 October 2018, were identified from institutional records of all Danish oncology departments. Clinical and treatment data were retrospectively collected. Descriptive statistics and survival analyses were performed. RESULTS: Data were available for 840 patients; 49% females. The median age was 68 years (19% were ≥75 years), 19% had PS ≥2, and 36% had moderate to severe comorbidity. The median OS (mOS) was 12.2 months; 15.1 months and 10.0 months in females and males, respectively. The median time-to-treatment discontinuation (mTTD) and median progression-free survival (mPFS) was 3.2 and 5.2 months, respectively. Patients with PS ≥2 had a mOS of 4.5 months, mTTD of 1.1 month, and mPFS of 2.0 months. In multivariable Cox regression analysis, male sex (HR = 1.35, 95% CI 1.11-1.62), PS >0 (PS 1, HR = 1.88, 95% CI 1.52-2.33; PS ≥2, HR = 4.15, 95% CI 3.13-5.5), liver metastases (HR = 1.72, 95% CI 1.34-2.22), and bone metastases (HR = 1.27, 95% CI 1.03-1.58) were significant poor prognostic OS factors. CONCLUSIONS: Danish real-world patients with advanced NSCLC treated with second- or subsequent-line ICI had an OS comparable to results from RCTs. Women, frail and older patients constituted a higher proportion than in previous RCTs. Clinical features associated with poor OS were male sex, PS ≥1 (in particular PS ≥2), bone-, and liver metastases.