[Immunophenotyping of lung tumors : An update]. / Immunphänotypisierung von Lungentumoren : Ein Update.

The WHO Classification of Lung Tumors (2015) established the use of immunohistochemical stainings for resection specimens, however, detailed recommendations had been missing. Now, an international expert panel has summarized key questions for daily routine practice and provided recommendations to assist the community in the appropriate use of immunohistochemistry in this context. This article provides an overview of the most important aspects.

Inherently Radiopaque Narrow-Size-Calibrated Microspheres: Proof of Principle in a Pig Embolization Model.

PURPOSE: To investigate radiopacity, size and size calibration, morphology, and vascular distribution of inherently radiopaque microspheres in vitro and in a pig embolization model. MATERIALS AND METHODS: We compared three types of microspheres: DCBead™ (size 100-300 µm) and Embozene™ (250 µm) as clinically established microspheres, and the prototype Visible (250 µm) that contains additional radiopaque material. Size and size calibration of microspheres were examined by laser diffraction. Pulmonary artery embolization was performed in 12 pigs, and radiopacity was examined by in vitro micro-computed tomography (CT), in vivo cone-beam CT, and ex vivo micro-CT after killing. Morphology and vascular distribution of microspheres were microscopically examined. RESULTS: In in vitro and ex vivo micro-CT, radiopacity of Visible was higher than that of Embozene™, whereas DCBead™ showed no radiopacity. In in vivo cone-beam CT, radiopacity was observed with Visible but not with Embozene™ and DCBead™. Laser diffraction revealed that 7.0% (Visible), 6.5% (Embozene™), and 22.5% (DCBead™) of microspheres were smaller than 223.5 µm. Visible and Embozene™ microspheres were very often located in bronchiolus-associated arteries, but rarely in subsegmental and capillary arteries, whereas DCBead™ were very often and often detected in bronchiolus-associated arteries and capillary arteries, respectively (and rarely in subsegmental arteries). CONCLUSION: After pulmonary artery embolization, Visible but not Embozene™ or DCBead™ provide in vivo radiopacity in cone-beam CT. In contrast to non-narrow-size-calibrated DCBead™, pulmonary artery embolization with narrow-size-calibrated Visible and Embozene™ result in a predictable arterial distribution without embolization-related hemorrhagic lung infarction.

Expression ratio of the TGFß-inducible gene MYO10 is prognostic for overall survival of squamous cell lung cancer patients and predicts chemotherapy response.

In lung cancer a deregulation of Transforming Growth Factor-ß (TGFß) signaling has been observed. Yet, the impact of TGFß in squamous cell carcinoma of the lung (LUSC) remained to be determined. We combined phenotypic and transcriptome-wide studies and showed that the stimulation of the LUSC cell line SK-MES1 with TGFß results in an increase of migratory invasive properties. The analysis of the dynamics of gene expression by next-generation sequencing revealed that TGFß stimulation orchestrates the upregulation of numerous motility- and actin cytoskeleton-related genes. Among these the non-muscle myosin 10 (MYO10) showed the highest upregulation in a LUSC patient cohort of the Cancer Genome Atlas (TCGA). Knockdown of MYO10 abrogated TGFß-induced collagen gel invasion of SK-MES1 cells. The analysis of MYO10 mRNA expression in paired tissues of 151 LUSC patients with corresponding 80-month clinical follow-up data showed that the mRNA expression ratio of MYO10 in tumor and tumor-free tissue is prognostic for overall survival of LUSC patients and predictive for the response of these patients to adjuvant chemotherapy. Thus, MYO10 represents a new clinical biomarker for this aggressive disease and due to its role in cellular motility and invasion could serve as a potential molecular target for therapeutic interventions in patients with LUSC.

[Aerogenic tumor seeding : A new invasive criterion for lung carcinomas]. / Aerogene Tumoraussaat (STAS) : Ein neues Invasionskriterium für Lungenkarzinome.

The new concept of spread through air spaces (STAS) was introduced for pulmonary adenocarcinomas in the 2015 WHO classification for lung cancer. Yet, available data demonstrate that STAS is of high prognostic impact and associated with specific clinic-pathological characteristics. This article provides a comprehensive overview of recent developments in this field.

PD-L1 expression in large cell neuroendocrine carcinoma of the lung.

OBJECTIVES: Large cell neuroendocrine carcinoma of the lung (LCNEC) is associated with an unfavorable prognosis and only few patients are eligible for surgery. In most patients, chemotherapy is recommended alone or in addition to resection. Novel immunotherapies blocking the PD-L1 pathway have been introduced into therapeutic regimens for NSCLC with great success. In order to evaluate a possible efficacy of an anti-PD-L1 therapy, we analyzed the frequency of PD-L1 expression in LCNEC. MATERIAL AND METHODS: We retrospectively reviewed data from 76 patients with LCNEC treated in our institution between 1998 and 2010. The expression of PD-L1 was examined on the tumor cells and the tumor surrounding tissue by immunohistochemistry. An expression of >1% was considered as positive. Statistical analysis was performed to determine significant predictors for survival. RESULTS: 56 of 76 patients with LCNEC were treated with a potentially therapeutic surgical approach. Tumor-specific survival (TSS) of the entire cohort was 29% at five years. 17 patients (22.3%) had PD-L1 positive tumors and 12 of these had no additional PD-L1 expression in the adjacent immune cell infiltrate. Tumor-flanking immune cells were found PD-L1 positive 28 patients; 16 of these had no additional expression on the tumor cells. The most considerable difference in survival was found when comparing patients with isolated PD-L1 expression on tumor cells and PD-L1 negative immune cell infiltrate to their counterpart (positive immune-cell infiltrate and PD-L1 negative tumor cell surface; 5-year TSS: 0% vs. 60%; p < 0.017). CONCLUSION: PD-L1 expression in LCNEC was associated with poorer survival whereas PD-L1 expression in the tumor microenvironment seemed to have a beneficial effect. Therapeutic approaches have to be evaluated in future.

Prevalence and clinical association of gene mutations through multiplex mutation testing in patients with NSCLC: results from the ETOP Lungscape Project.

Background: Reported prevalence of driver gene mutations in non-small-cell lung cancer (NSCLC) is highly variable and clinical correlations are emerging. Using NSCLC biomaterial and clinical data from the European Thoracic Oncology Platform Lungscape iBiobank, we explore the epidemiology of mutations and association to clinicopathologic features and patient outcome (relapse-free survival, time-to-relapse, overall survival). Methods: Clinically annotated, resected stage I-III NSCLC FFPE tissue was assessed for gene mutation using a microfluidics-based multiplex PCR platform. Mutant-allele detection sensitivity is >1% for most of the ∼150 (13 genes) mutations covered in the multiplex test. Results: Multiplex testing has been carried out in 2063 (76.2%) of the 2709 Lungscape cases (median follow-up 4.8 years). FFPE samples mostly date from 2005 to 2008, yet recently extracted DNA quality and quantity was generally good. Average DNA yield/case was 2.63 µg; 38 cases (1.4%) failed QC and were excluded from study; 95.1% of included cases allowed the complete panel of mutations to be tested. Most common were KRAS, MET, EGFR and PIK3CA mutations with overall prevalence of 23.0%, 6.8%, 5.4% and 4.9%, respectively. KRAS and EGFR mutations were significantly more frequent in adenocarcinomas: PIK3CA in squamous cell carcinomas. MET mutation prevalence did not differ between histology groups. EGFR mutations were found predominantly in never smokers; KRAS in current/former smokers. For all the above mutations, there was no difference in outcome between mutated and non-mutated cases. Conclusion: Archival FFPE NSCLC material is adequate for multiplex mutation analysis. In this large, predominantly European, clinically annotated stage I-III NSCLC cohort, none of the mutations characterized showed prognostic significance.

Successful treatment of a recurrent granulation polyp in the airways with high-dose-rate brachytherapy: a case report.

BACKGROUND: Benign central airway tumors are very rare diseases. Their unspecific symptoms are responsible for late diagnosis. Endoscopic interventions with different techniques and tools are widely used for their treatment. However, in certain cases interventional endoscopy might be unsuccessful and therefore other methods such as high-dose-rate brachytherapy could be a therapeutic option. CASE PRESENTATION: A 76-year-old white German woman was referred to our clinic for an endoscopic treatment of a recurrent granulation polyp in her left main bronchus. She had dyspnea, coughing, and mucus retention. Three times resections via bronchoscopy were performed within less than a year. After each intervention the polyp regrew inside her left main bronchus causing a repeat of the initial symptoms. She presented to our clinic less than 1 month since the last intervention. Twice we performed a rigid bronchoscopy in total anesthesia where we resected the granulation polyp with a snare wire loop and did an argon plasma coagulation of its base. Due to the recurrent growing of the granuloma, we performed a high-dose-rate brachytherapy in conscious sedation after another interventional bronchoscopy with a resection of the polyp and argon plasma coagulation of the base. Three months after brachytherapy our patient came to our clinic for a follow-up with none of the initial symptoms. Only a small remnant of the polyp without a significant occlusion of her bronchus was visualized by bronchoscopy. Furthermore, 6 months after brachytherapy she was not presenting any of the initial symptoms. CONCLUSIONS: This case report shows that high-dose-rate brachytherapy is a therapeutic option for the treatment of benign airway stenosis when other interventional treatments are not or are less than successful. However, further investigations are needed to prove the effectiveness and reliability of the method.

[The new TNM classification for lung tumors : Changes and the assessment of multiple tumor foci]. / Die neue TNM-Klassifikation für Lungentumoren : Änderungen und Bewertung multipler Tumorherde.

Recently a new TNM classification for tumors of the lung was published, encompassing some relevant changes, for example how to deal with multiple lung tumors. This article comprehensively describes respective changes. Furthermore, background information on how the new TNM classification was built and what should be done in the future to further improve prognosis and outcome prediction is reviewed.

ALK-Testing in non-small cell lung cancer (NSCLC): Immunohistochemistry (IHC) and/or fluorescence in-situ Hybridisation (FISH)?: Statement of the Germany Society for Pathology (DGP) and the Working Group Thoracic Oncology (AIO) of the German Cancer Society e.V. (Stellungnahme der Deutschen Gesellschaft für Pathologie und der AG Thorakale Onkologie der Arbeitsgemeinschaft Onkologie/Deutsche Krebsgesellschaft e.V.).

The EML4-ALK pathway plays an important role in a significant subset of non-small cell lung cancer patients. Treatment options such as ALK tyrosine kinase inhibitors lead to improved progression free survival and overall survival. These therapeutic options are chosen on the basis of the identification of the underlying genetic signature of the EML-ALK translocation. Efficient and easily accessible testing tools are required to identify eligible patients in a timely fashion. While FISH techniques are commonly used to detect this translocation, the broad implementation of this type of ALK testing into routine diagnostics is not optimal due to technical, structural and financial reasons. Immunohistochemical techniques to screen for EML4-ALK translocations may therefore play an important role in the near future. This consensus paper provides recommendations for the test algorithm and quality of the respective test approaches, which are discussed in the light of the current literature.

[Predictive PD-L1 immunohistochemistry for non-small cell lung cancer : Current state of the art and experiences of the first German harmonization study]. / Prädiktive PD-L1-Immunhistochemie beim nichtkleinzelligen Bronchialkarzinom : Aktueller Stand und Erfahrungen der ersten deutschen Harmonisierungsstudie.

BACKGROUND: Antibodies against PD-1 and PD-L1 can cause strong and durable anti-tumor immune responses in non-small cell lung cancer (NSCLC). Immunohistochemistry for PD-L1 (PD-L1 IHC) was tested as a predictive biomarker. Several IHC assays and interpretation criteria were developed in parallel. AIM: The clinical significance of PD-L1 IHC in NSCLC and the optimum method for staining and interpretation of the results are the subject of ongoing studies. The diagnostic application of immunotherapy in NSCLC necessitates harmonization of PD-L1 IHC to obtain evidence for guidelines; therefore, a consensus opinion on a well-founded diagnostic mode of testing should be defined based on published studies and the results of the first German PD-L1 IHC harmonization study. METHODS: 1. Summary of the current data situation. 2. Evaluation of the first German PD-L1 IHC harmonization study (centralized, staining with PD-L1 IHC analogous to studies, 15 cases of NSCLC, 4 IHC study assays [28­8, 22C3, SP142 and SP263] and scoring by 9 pathologists). RESULTS: The use of PD-L1 IHC in NSCLC is suitable for identification of patients with an increased probability of a clinical benefit from immunotherapy. The various proportional cut-offs used to interpret the staining results can be summarized in a total score, which can be reproducibly assessed. The staining patterns of the four assays investigated were, however, not congruent in all situations. DISCUSSION: In principle, the use of PD-L1 IHC for assessment of the expression in tumor cells is a reliably determinable biomarker. Evaluation algorithms should be based on published clinical trials. For NSCLC approvals with obligatory PD-L1 IHC are to be expected but it remains to be seen to what extent PD-L1 IHC will be implemented in the clinical routine.

[Application and interpretation of the R classification for lung cancer : Results of a survey of certified lung cancer centers]. / Anwendung und Interpretation der R­Klassifikation beim Lungenkarzinom : Ergebnisse einer Umfrage an zertifizierten Lungenkrebszentren.

The residual (R) tumor classification is an essential, even if facultative component of the TNM classification; however, it should alway be included in the pathology results of certified lung cancer centers. In discussions it becomes clear again and again that different hospitals and departments have different approaches and interpretations with respect to the R status after lung resection. We carried out a questionnaire-based survey of pathologists (with specialization in pulmonary pathology) and thoracic surgeons on the application of the R classification for lung tumors. The results of the survey revealed the different perceptions of the participating centers with respect to application and interpretation, which results in divergent decisions for adjuvant therapy and complicates the comparability of national and international studies. The results of the survey are especially valuable because all participants have a high level of expertise in the field of thoracic pathology and the data reflect the current practice in certified lung cancer centers. It appears to be necessary to examine the application and interpretation of the R classification for lung cancer more closely in an interdisciplinary exchange and to produce a catalogue of criteria to guarantee at least a better national standardization.

[ALK-Diagnostics in NSCLC - Immunohistochemistry (IHC) and/or Fluorescence-in-situ Hybridisation (FISH)]. / ALK-Testung beim nicht-kleinzelligen Lungenkarzinom (NSCLC): Immunhistochemie (IHC) und/oder Fluoreszenz-in-situ-Hybridisierung (FISH)?

The EML4-ALK pathway plays an important role in a significant subset of non-small cell lung cancer patients. Treatment options such as tyrosine kinase inhibitors directed against the EML4-ALK signalling pathway lead to improved progression free and overall survival. These therapeutic options are chosen on the basis of the identification of the underlying genetic signature of the EML-ALK translocation. Efficient and easily accessible testing tools are required to identify the patients in time. While FISH techniques have been implemented to characterize this translocation for some time, the implementation of this testing is hampered by its broad use of resources. Immunohistochemical techniques to identify and screen for EML4-ALK translocations may play an important role in the near future. This consensus paper offers recommendations of the sequence and quality of the respective test approaches which are validated on the basis of the current literature.

Patch-Based Nonlinear Image Registration for Gigapixel Whole Slide Images.

OBJECTIVE: Image registration of whole slide histology images allows the fusion of fine-grained information-like different immunohistochemical stains-from neighboring tissue slides. Traditionally, pathologists fuse this information by looking subsequently at one slide at a time. If the slides are digitized and accurately aligned at cell level, automatic analysis can be used to ease the pathologist's work. However, the size of those images exceeds the memory capacity of regular computers. METHODS: We address the challenge to combine a global motion model that takes the physical cutting process of the tissue into account with image data that is not simultaneously globally available. Typical approaches either reduce the amount of data to be processed or partition the data into smaller chunks to be processed separately. Our novel method first registers the complete images on a low resolution with a nonlinear deformation model and later refines this result on patches by using a second nonlinear registration on each patch. Finally, the deformations computed on all patches are combined by interpolation to form one globally smooth nonlinear deformation. The NGF distance measure is used to handle multistain images. RESULTS: The method is applied to ten whole slide image pairs of human lung cancer data. The alignment of 85 corresponding structures is measured by comparing manual segmentations from neighboring slides. Their offset improves significantly, by at least 15%, compared to the low-resolution nonlinear registration. CONCLUSION/SIGNIFICANCE: The proposed method significantly improves the accuracy of multistain registration which allows us to compare different antibodies at cell level.

[Diagnosis, prognosis, and prediction of non-small cell lung cancer. Importance of morphology, immunohistochemistry and molecular pathology]. / Diagnose, Prognose und Prädiktion nicht-kleinzelliger Lungenkarzinome. Bedeutung von Morphologie, Immunhistochemie und Molekularpathologie.

Tumor diagnostics are based on histomorphology, immunohistochemistry and molecular pathological analysis of mutations, translocations and amplifications which are of diagnostic, prognostic and/or predictive value. In recent decades only histomorphology was used to classify lung cancer as either small (SCLC) or non-small cell lung cancer (NSCLC), although NSCLC was further subdivided in different entities; however, as no specific therapy options were available classification of specific subtypes was not clinically meaningful. This fundamentally changed with the discovery of specific molecular alterations in adenocarcinoma (ADC), e.g. mutations in KRAS, EGFR and BRAF or translocations of the ALK and ROS1 gene loci, which now form the basis of targeted therapies and have led to a significantly improved patient outcome. The diagnostic, prognostic and predictive value of imaging, morphological, immunohistochemical and molecular characteristics as well as their interaction were systematically assessed in a large cohort with available clinical data including patient survival. Specific and sensitive diagnostic markers and marker panels were defined and diagnostic test algorithms for predictive biomarker assessment were optimized. It was demonstrated that the semi-quantitative assessment of ADC growth patterns is a stage-independent predictor of survival and is reproducibly applicable in the routine setting. Specific histomorphological characteristics correlated with computed tomography (CT) imaging features and thus allowed an improved interdisciplinary classification, especially in the preoperative or palliative setting. Moreover, specific molecular characteristics, for example BRAF mutations and the proliferation index (Ki-67) were identified as clinically relevant prognosticators. Comprehensive clinical, morphological, immunohistochemical and molecular assessment of NSCLCs allow an optimized patient stratification. Respective algorithms now form the backbone of the 2015 lung cancer World Health Organization (WHO) classification.

[ROS1-Translocations in Non-Small Cell Lung Cancer]. / ROS1-Translokationen im nicht-kleinzelligen Lungenkarzinom.

AIM: Summary of prevalence, testing and treatment approaches in patients with non-small cell lung cancer (NSCLC) and ROS1 activation. METHODS: Internet-based search for clinical and preclinical studies as well as search for ongoing studies in web-based databases. RESULTS: ROS1 translocations lead to tyrosine kinase activation and can be detected in 1 - 2% of all NSCLC and in 3 - 6% of pulmonary adenocarcinoma patients, respectively, using in situ hybridization techniques. RESULTS from phase I clinical studies using the ROS1 inhibitor crizotinib indicate response rates of 70 - 80% and a median progression-free survival of about 19 months. The therapy was generally well tolerated. CONCLUSIONS: NSCLC harbouring ROS1-translocations can be treated with targeted therapy leading to promising response and survival in patients. Hence, these alterations should be included into current molecular testing panels in stage IV pulmonary adenocarcinomas.

Improved diagnostics targeting c-MET in non-small cell lung cancer: expression, amplification and activation?

BACKGROUND: Several c-MET targeting inhibitory molecules have already shown promising results in the treatment of patients with Non-small Cell Lung Cancer (NSCLC). Combination of EGFR- and c-MET-specific molecules may overcome EGFR tyrosine kinase inhibitor (TKI) resistance. The aim of this study was to allow for the identification of patients who might benefit from TKI treatments targeting MET and to narrow in on the diagnostic assessment of MET. METHODS: 222 tumor tissues of patients with NSCLC were analyzed concerning c-MET expression and activation in terms of phosphorylation (Y1234/1235 and Y1349) using a microarray format employing immunohistochemistry (IHC). Furthermore, protein expression and MET activation was correlated with the amplification status by Fluorescence in Situ Hybridization (FISH). RESULTS: Correlation was observed between phosphorylation of c-MET at Y1234/1235 and Y1349 (spearman correlation coefficient rs = 0.41; p < 0.0001). No significant correlation was shown between MET expression and phosphorylation (p > 0.05). c-MET gene amplification was detected in eight of 214 patients (3.7%). No significant association was observed between c-MET amplification, c-MET protein expression and phosphorylation. CONCLUSION: Our data indicate, that neither expression of c-MET nor the gene amplification status might be the best way to select patients for MET targeting therapies, since no correlation with the activation status of MET was observed. We propose to take into account analyzing the phosphorylation status of MET by IHC to select patients for MET targeting therapies. Signaling of the receptor and the activation of downstream molecules might be more crucial for the benefit of therapeutics targeting MET receptor tyrosine kinases than expression levels alone.