Patient selection for anti-PD-1/PD-L1 therapy in advanced non-small-cell lung cancer: implications for clinical practice.

Immune checkpoint inhibitors targeting PD-1 or PD-L1 represent a standard treatment option for patients with advanced non-small-cell lung cancer. However, a substantial proportion of patients will not benefit from these treatments, and robust biomarkers are required to help clinicians select patients who are most likely to benefit. Here, we discuss the available evidence on the utility of clinical characteristics in the selection of patients with advanced non-small-cell lung cancer as potential candidates for single-agent anti-PD-1/PD-L1 therapy, and provide practical guidance to clinicians on identifying those patients who are most likely to benefit. Recommendations on the use of immune checkpoint inhibitor in clinically challenging populations are also provided.

Non-Small Cell Lung Cancer, PD-L1, and the Pathologist.

CONTEXT: Although most primary cancers of the lung carry a heavy mutational load and will potentially present many "nonself" antigens to the immune system, there are a wide range of possible mechanisms for tumors to avoid so-called immune surveillance. One such mechanism is the adoption of immune checkpoints to inhibit the host immune response. Immune checkpoint inhibitors show great promise in the treatment of advanced non-small cell lung cancer. OBJECTIVE: To discuss the possibility of biomarker selection of patients for these therapies. This is becoming a much debated issue, and the immunohistochemical detection of Programmed Death Ligand 1 (PD-L1), the ligand for the inhibitory Programmed Death receptor 1 (PD-1) checkpoint, is one possible biomarker. Data so far available show some conflicting results, but PD-L1 immunohistochemistry looks likely to be introduced into clinical use for selecting patients for treatment with anti-PD-1 or anti-PD-L1 therapies. Given that there are 4 such drugs rapidly approaching regulatory approval, each with its own independent PD-L1 immunohistochemistry biomarker test, both oncologists and pathologists face some significant challenges. DATA SOURCES: Peer-reviewed literature and meeting proceedings, especially during the last 12 months, were used. CONCLUSIONS: The biology of PD-1/PD-L1 is complex, the clinical data for these drugs show considerable variation, the selection performance of the PD-L1 biomarker test is not perfect, and the existence of 4 drug/test combinations adds significantly to the problems faced. This article addresses some of the background to this therapeutic problem and discusses some of the issues ahead.

Association between gene expression profiles and clinical outcome of pemetrexed-based treatment in patients with advanced non-squamous non-small cell lung cancer: exploratory results from a phase II study.

INTRODUCTION: We report exploratory gene-expression profiling data from a single-arm Phase-II-study in patients with non-squamous (ns)NSCLC treated with pemetrexed and cisplatin. Previously disclosed results indicated a significant association of low thymidylate-synthase (TS)-expression with longer progression-free and overall survival (PFS/OS). METHODS: Treatment-naïve nsNSCLC patients (IIIB/IV) received 4 cycles of pemetrexed/cisplatin; non-progressing patients continued on pemetrexed-maintenance. Diagnostic tissue-samples were used to assess TS-expression by immunohistochemistry (IHC) and mRNA-expression array-profiling (1,030 lung cancer-specific genes). Cox proportional-hazard models were applied to explore the association between each gene and PFS/OS. Genes significantly correlated with PFS/OS were further correlated with TS-protein expression (Spearman-rank). Unsupervised clustering was applied to all evaluable samples (n = 51) for all 1,030 genes and an overlapping 870-gene subset associated with adenocarcinoma (ADC, n = 47). RESULTS: 51/70 tissue-samples (72.9%) were evaluable; 9 of 1,030 genes were significantly associated with PFS/OS (unadjusted p < 0.01, genes: Chromosome 16 open reading frame 89, napsin A, surfactant protein B, aquaporin 4, TRAF2- and Nck-interacting kinase, Lysophosphatidylcholine acyltransferase 1, Interleukin 1 receptor type II, NK2 homeobox 1, ABO glycosyl-transferase); expression for all except IL1R2 correlated negatively with nuclear TS-expression (statistically significant for 5/8 genes, unadjusted p<0.01). Cluster-analysis based on 1,030 genes revealed no clear trend regarding PFS/OS; the ADC-based cluster analysis identified 3 groups (n = 21/11/15) with median (95%CI) PFS of 8.1(6.9,NE)/2.4(1.2,NE)/4.4(1.2,NE) months and OS of 20.3(17.5,NE)/4.3(1.4,NE)/8.3(3.9,NE) months, respectively. CONCLUSIONS: These exploratory gene-expression profiling results describe genes potentially linked to low TS-expression. Nine genes were significantly associated with PFS/OS but could not be differentiated as prognostic or predictive as this was a single-arm study. Although these hypotheses-generating results are interesting, they provide no evidence to change the current histology-based treatment approach with pemetrexed.

Exploring patterns of recurrent melanoma in Northeast Scotland to inform the introduction a digital self-examination intervention.

BACKGROUND: Melanoma incidence is growing and more people require follow-up to detect recurrent melanoma quickly. Those detecting their own recurrent melanoma appear to have the best prognosis, so total skin self examination (TSSE) is advocated, but practice is suboptimal. A digital intervention to support TSSE has potential but it is not clear which patient groups could benefit most. The aim of this study was to explore cutaneous melanoma recurrence patterns between 1991 and 2012 in Northeast Scotland. The objectives were to: determine how recurrent melanomas were detected during the period; explore factors potentially predictive of mode of recurrence detection; identify groups least likely to detect their own recurrent melanoma and with most potential to benefit from digital TSSE support. METHODS: Pathology records were used to identify those with a potential recurrent melanoma of any type (local, regional and distant). Following screening of potential cases available secondary care-held records were subsequently scrutinised. Data was collected on demographics and clinical characteristics of the initial and recurrent melanoma. Data were handled in Microsoft Excel and transported into SPSS 20.0 for statistical analysis. Factors predicting detection at interval or scheduled follow-up were explored using univariate techniques, with potentially influential factors combined in a multivariate binary logistic model to adjust for confounding. RESULTS: 149 potential recurrences were identified from the pathology database held at Aberdeen Royal Infirmary. Reliable data could be obtained on 94 cases of recurrent melanoma of all types. 30 recurrences (31.9%) were found by doctors at follow-up, and 64 (68.1%) in the interval between visits, usually by the patient themselves. Melanoma recurrences of all types occurring within one-year were significantly more likely to be found at follow-up visits, and this remained so following adjustment for other factors that could be used to target digital TSSE support. CONCLUSIONS: A digital intervention should be offered to all newly diagnosed patients. This group could benefit most from optimal TSSE practice.

Thymidylate synthase expression and outcome of patients receiving pemetrexed for advanced nonsquamous non-small-cell lung cancer in a prospective blinded assessment phase II clinical trial.

INTRODUCTION: In retrospective analyses of patients with nonsquamous non-small-cell lung cancer treated with pemetrexed, low thymidylate synthase (TS) expression is associated with better clinical outcomes. This phase II study explored this association prospectively at the protein and mRNA-expression level. METHODS: Treatment-naive patients with nonsquamous non-small-cell lung cancer (stage IIIB/IV) had four cycles of first-line chemotherapy with pemetrexed/cisplatin. Nonprogressing patients continued on pemetrexed maintenance until progression or maximum tolerability. TS expression (nucleus/cytoplasm/total) was assessed in diagnostic tissue samples by immunohistochemistry (IHC; H-scores), and quantitative reverse-transcriptase polymerase chain reaction. Cox regression was used to assess the association between H-scores and progression-free/overall survival (PFS/OS) distribution estimated by the Kaplan-Meier method. Maximal χ² analysis identified optimal cutpoints between low TS- and high TS-expression groups, yielding maximal associations with PFS/OS. RESULTS: The study enrolled 70 patients; of these 43 (61.4%) started maintenance treatment. In 60 patients with valid H-scores, median (m) PFS was 5.5 (95% confidence interval [CI], 3.9-6.9) months, mOS was 9.6 (95% CI, 7.3-15.7) months. Higher nuclear TS expression was significantly associated with shorter PFS and OS (primary analysis IHC, PFS: p < 0.0001; hazard ratio per 1-unit increase: 1.015; 95%CI, 1.008-1.021). At the optimal cutpoint of nuclear H-score (70), mPFS in the low TS- versus high TS-expression groups was 7.1 (5.7-8.3) versus 2.6 (1.3-4.1) months (p = 0.0015; hazard ratio = 0.28; 95%CI, 0.16-0.52; n = 40/20). Trends were similar for cytoplasm H-scores, quantitative reverse-transcriptase polymerase chain reaction and other clinical endpoints (OS, response, and disease control). CONCLUSIONS: The primary endpoint was met; low TS expression was associated with longer PFS. Further randomized studies are needed to explore nuclear TS IHC expression as a potential biomarker of clinical outcomes for pemetrexed treatment in larger patient cohorts.

Developing a complex intervention to reduce time to presentation with symptoms of lung cancer.

BACKGROUND: Lung cancer is the commonest cause of cancer in Scotland and is usually advanced at diagnosis. Median time between symptom onset and consultation is 14 weeks, so an intervention to prompt earlier presentation could support earlier diagnosis and enable curative treatment in more cases. AIM: To develop and optimise an intervention to reduce the time between onset and first consultation with symptoms that might indicate lung cancer. DESIGN AND SETTING: Iterative development of complex healthcare intervention according to the MRC Framework conducted in Northeast Scotland. METHOD: The study produced a complex intervention to promote early presentation of lung cancer symptoms. An expert multidisciplinary group developed the first draft of the intervention based on theory and existing evidence. This was refined following focus groups with health professionals and high-risk patients. RESULTS: First draft intervention components included: information communicated persuasively, demonstrations of early consultation and its benefits, behaviour change techniques, and involvement of spouses/partners. Focus groups identified patient engagement, achieving behavioural change, and conflict at the patient-general practice interface as challenges and measures were incorporated to tackle these. Final intervention delivery included a detailed self-help manual and extended consultation with a trained research nurse at which specific action plans were devised. CONCLUSION: The study has developed an intervention that appeals to patients and health professionals and has theoretical potential for benefit. Now it requires evaluation.

Subtyping of undifferentiated non-small cell carcinomas in bronchial biopsy specimens.

INTRODUCTION: The emergence of treatments for non-small cell lung carcinoma (NSCLC) with differential efficacy and toxicity between subtypes has highlighted the importance of specific pathologic NSCLC subtyping. Most NSCLCs are inoperable, and pathologic diagnosis is made only on small tissue samples that are prone to diagnostic inaccuracy. In a substantial proportion of cases, standard morphology cannot specifically subtype the tumor, necessitating a diagnosis of NSCLC-not otherwise specified (NOS). Histochemical staining for mucin and immunohistochemical (IHC) identification of NSCLC subtype-associated markers could help predict the final subtype of resected NSCLCs diagnosed as NSCLC-NOS on preoperative bronchial biopsy samples. METHODS: Paraffin sections of 44 bronchial biopsy samples diagnosed as NSCLC-NOS were stained for mucin (Alcian blue/periodic acid Schiff) and thyroid transcription factor 1 by IHC-(markers of adenocarcinoma), and for S100A7, cytokeratin 5/6, high molecular weight cytokeratins, and p63 proteins-markers of squamous cell carcinoma. A predictive staining panel was derived from statistical analysis after comparing staining profiles with the final postsurgical NSCLC subtype. This panel was prospectively applied to 82 small biopsy samples containing NSCLC. RESULTS: True NSCLC subtype of undifferentiated NSCLC samples was best predicted using Alcian blue/periodic acid Schiff plus p63 and thyroid transcription factor 1 IHC, allowing specific subtyping in 73% of NSCLC-NOS cases with 86% accuracy. When applied prospectively, this staining panel showed 100% concordance with specific NSCLC morphologic subtyping in small biopsies. CONCLUSION: This approach can facilitate treatment selection by accurately predicting the subtype in undifferentiated NSCLC biopsies, reducing to 7% the proportion of cases without a definite or probable histologic subtype.

Quantitative analysis of tumor in bronchial biopsy specimens.

BACKGROUND: Diagnostic bronchial biopsy samples from lung cancer patients may be used for molecular biologic analyses to help select therapy and provide prognostic information. Some have suggested that direct molecular analysis of bronchial biopsy fragments may be feasible, bypassing histologic examination. We analyzed a series of 100 bronchial biopsy specimens in lung cancer patients to assess the frequency and quantity of tumor present in biopsy samples. METHODS: The proportion of tumor in bronchial biopsy specimens was assessed by measuring the tumor area in histologic sections using computer-aided morphometry. RESULTS: In only 48% of cases did all the biopsy fragments contain some tumor. The median number of fragments obtained at bronchoscopy was 4; median number actually containing tumor was 3. The mean total surface area of tumor (as a percentage of the total sample area) in biopsy fragments was, for all cases, 33.4%; median area 28%. Biopsies with small cell carcinoma had more tumor (mean area 46.5%, median 49%; p = 0.0006) than all other non-small cell carcinoma cases. CONCLUSION: Malignant bronchial biopsy samples frequently contain limited amounts of primary carcinoma. Often, one or more of the biopsy fragments will not contain tumor. This has important implications for the storage and use of bronchial biopsy samples for genetic analysis.

Designing an integrated follow-up programme for people treated for cutaneous malignant melanoma: a practical application of the MRC framework for the design and evaluation of complex interventions to improve health.

BACKGROUND: Complex health care interventions are difficult to design and evaluate, so the UK Medical Research Council (MRC) has developed a 'framework for the design and evaluation of complex health care intervention'. Researchers differ in applying the framework. OBJECTIVE: To describe and critically evaluate how the two initial phases of the MRC framework facilitate the design of an integrated follow-up programme for cutaneous melanoma to a standard suitable for testing in an exploratory randomized trial. Design of study. Literature review, expert groups, semi-structured interviews and pilot exercise to develop an intervention. SETTING: A department of academic primary care. Two general practices. METHODS: Four techniques were used-iterative literature review, a steering group, semi-structured telephone interviews and an operationalization exercise. These techniques were used simultaneously and iteratively to complete the theoretical preclinical and phase I modelling of the MRC framework when developing an integrated follow-up programme for cutaneous melanoma. RESULTS: Components of an integrated follow-up programme for cutaneous malignant melanoma were identified, developed and refined into a practical intervention comprising GP training; structured protocol-driven appointments; a centralized recall system; a rapid access pathway and a patient information booklet. Several barriers that could have derailed the successful implementation of the intervention, including the different perspectives of stakeholders and resource needs in general practice were identified. The value of the principles of the initial two phases of the MRC framework in guiding the development of complex health care interventions was supported. CONCLUSIONS: We recommend that the first two phases of the MRC framework be used iteratively and simultaneously when developing complex health care interventions.

Tumor transcriptome reveals the predictive and prognostic impact of lysosomal protease inhibitors in non-small-cell lung cancer.

PURPOSE: Insight into clinical response to platinum-based chemotherapy (PBC) in non-small-cell lung cancer (NSCLC). METHODS: Matched tumor and nontumor lung tissues from PBC-treated NSCLC patients (four nonresponders and four responders) and tumor tissue from an independent test set (four nonresponders and four responders), were profiled using microarrays. Lysosomal protease inhibitors SerpinB3 and cystatin C were highly correlated with clinical response and were further evaluated by immunohistochemistry in PBC-treated patients (36 prechemotherapy and 13 postchemotherapy). Investigation of the pathogenic and prognostic significance of SerpinB3 was performed in 251 primary tumors, with 64 regional lymph node pairs, from chemotherapy-naïve NSCLC patients using immunohistochemistry. RESULTS: Bioinformatic analyses of gene expression in the training set identified a gene set (n = 17) that separated all patients in the training and test sets (n = 16) according to response in hierarchical clustering. Transcriptome profiling revealed that SerpinB3 mRNA was highly correlated with degree of response (r = -0.978; P < .0001) and was a clear outlier (nonresponders:responders > 50-fold). SerpinB3 protein expression was correlated with clinical response in PBC-treated NSCLC patients (P = .045). Expression of SerpinB3 and cystatin C, relative to the target, protease cathepsin B, was independently predictive of response (odds ratio, 17.8; 95% CI, 2.0 to 162.4; P = .01), with an accuracy of 72%. High SerpinB3 expression levels, invariably associated with chemoresistance, had contrasting prognostic impact in untreated squamous cell carcinomas (hazard ratio [HR], 0.43; 95% CI, 0.18 to 0.93) or adenocarcinomas (HR, 2.09; 95% CI, 1.03 to 4.72). CONCLUSION: This provides the first comprehensive molecular characterization of clinical responsiveness to PBC in NSCLC and reveals the predictive and prognostic impact of two lysosomal protease inhibitors, potentially representing novel targets for NSCLC therapeutics.

Gene expression profiling in non-small cell lung cancer: from molecular mechanisms to clinical application.

Non-small cell lung cancer (NSCLC) is the most common cause of premature death from malignant disease in western countries. A better understanding of the molecular mechanisms underlying NSCLC etiology, pathogenesis, and therapeutics will lead to improved clinical outcomes. Recent technological advances in gene expression profiling (in particular, with cDNA and oligonucleotide microarrays) allow the simultaneous analysis of the expression of thousands of genes. In this review, the technology of global gene expression profiling is discussed, and the progress made thus far with it in NSCLC is reviewed. A new molecular classification of NSCLC has been developed, which has provided important insights into etiology and pathogenesis. Other studies have found potential biomarkers for NSCLC that may be of use in diagnosis, screening, and assessing the effectiveness of therapy. Finally, advances have been made in the understanding of the molecular mechanisms of NSCLC progression and the molecular mechanisms of action of currently used cytotoxic drugs. This may facilitate the improvement of current therapeutics and the identification of novel targets. Taken together, these advances hold the promise of an improved understanding of the molecular biology of NSCLC and its treatment, which in turn will lead to improved outcomes for this deadly disease.

Expression of Fhit, cell adhesion molecules and matrix metalloproteinases in atypical adenomatous hyperplasia and pulmonary adenocarcinoma.

Invasive parenchymal-type lung adenocarcinoma develops from atypical adenomatous hyperplasia (AAH), through an intermediate in situ stage of bronchioloalveolar carcinoma (BAC). We examined the expression of the putative tumour suppressor gene product Fhit, cell adhesion molecules CD44v6, E-cadherin and beta-catenin, and matrix metalloproteinase 2 and its inhibitor, TIMP-2, in a range of AAH lesions, BACs and invasive adenocarcinomas, to determine the changes in molecular expression associated with this form of neoplastic progression. Sections of formalin-fixed wax-embedded archival tissue were stained by standard Immunohistochemical techniques and scored semi-quantitatively, resulting in a grading of negative/low- or high-level staining. Fhit protein was retained at high levels in over 90% of AAH and 83% of BAC, but was found in only 6% of stromally invasive tumours (p < 0.0001). CD44v6 staining was high-level in 64% of AAH but fell to 26% in stromally invasive tumour (p = 0.007). E-cadherin and beta-catenin showed the opposite, with more high-level staining as adenocarcinoma developed (p < 0.001). High-level MMP-2 and TIMP-2 expression was relatively infrequent in AAH (32% and 40% respectively), rose in BAC (89% each) but fell in stromally invasive tumour (31% and 17% respectively) (p < 0.01). Unlike in central bronchial carcinogenesis, loss of Fhit expression is a relatively late event in this putative progression of lung adenocarcinogenesis, and has potential as a surrogate marker of invasion, which could be of value in screening patients for lung cancer. Loss of CD44v6 expression follows the convention of falling adhesion molecule expression as malignancy develops. Increased expression of E-cadherin and beta-catenin may reflect increased cell-cell contact as tissue architecture changes in the transition from AAH to adenocarcinoma. Loss of MMP-2 and TIMP-2 in stromally invasive tumour may reflect a particular role for MMP-2 at the BAC stage, with later down-regulation of this particular enzyme.

Effect of grapefruit juice intake on etoposide bioavailability.

PURPOSE: Oral administration of etoposide is limited by the high degree of unpredictable variation in systemic availability. This pilot study was conducted to evaluate the potential of pretreatment with grapefruit juice for improving the use of oral etoposide. METHODS: In a randomized crossover study, six patients were sequentially treated with 50 mg IV etoposide over 1 h, 50 mg orally, or 50 mg orally post grapefruit juice on day 1, day 4, and day 8. Blood samples were drawn up to 24 h after the end of infusion and oral drug administration. Plasma etoposide concentrations were determined by reversed-phase HPLC with UV detection. A two-compartment model was used for pharmacokinetic parameter estimation. Pharmacokinetic parameters were evaluated using descriptive statistics. RESULTS: Pretreatment with grapefruit juice resulted in an unexpected decrease of 26.2% in the AUC after oral treatment. Median absolute bioavailability with and without pretreatment with grapefruit juice was 52.4% and 73.2%, respectively. Interindividual variability was large in all treatment arms. CONCLUSION: Grapefruit juice seems to reduce rather than increase oral bioavailability of etoposide. Moreover, we did not observe a reduction in interpatient variability of bioavailability.

Evaluation of NQO1 gene expression and variant allele in human NSCLC tumors and matched normal lung tissue.

NQO1 gene expression was evaluated by RT-PCR and SNP status by RFLP in matched samples of lung tumors and adjacent normal tissue. NQO1 was found to be overexpressed in lung tumors when compared to matched normal lung tissue. The mean expression in normal lung tissue was 28.26 x 10(-14) ng/microl +/- 44.9 SD and 61.46 x 10(-14) ng/microl +/- 103.2 SD in lung tumors. NQO1 gene expression was higher in the tumor than in the matched normal lung tissue in 27/50 (59%) patients (p=0.014). In the normal samples, 25 (50%) were wild-type, 16 were heterozygotes (32%) and 8 had the SNP (16%). In the matched tumor samples 14 were wild-type (28%), 16 were heterozygous (32%) and 19 (38%) had the SNP (p=0.0043). The genomic NQO1 mutation was associated with survival in a pilot study of stage II/III NSCLC patients. Patients with a homozygous SNP genotype had a significantly shorter survival (median 12 months), than heterozygous or homozygous wild-type patients (median 41 months) (p=0.007), suggesting NQO1 may be important in chemosensitivity as well as the pathogenesis of lung cancer and NQO1 genotyping may be a useful component of pharmacogenetic strategies for the treatment of NSCLC.