Induction of metallothionein expression by supplementation of zinc induces resistance against platinum-based treatment in malignant pleural mesothelioma

Background

Malignant pleural mesothelioma (MPM) is an aggressive tumor with a dismal prognosis. Currently, multimodality treatment including chemotherapy with cisplatin or carboplatin in combination with pemetrexed offers the best options. Detoxification of heavy metals in the cell by metallothioneins (MT) is associated with early failure to platin-based chemotherapy. The induction of MTs gene expression or its enzyme results in saturation by exposure to metal ions such as zinc or cadmium. Its therapeutically effect is still not analyzed in depth.

Methods

In our study, we investigated three MPM cell lines and one fibroblast cell line in the course of cisplatin treatment and supplementation of zinc. Cell state analyses via an enzyme-activity based assay were performed. With this, we were able to analyze apoptosis, necrosis and viability of cells. Additionally, we tested treated cells for changes in metallothionein IIA (MT2A) expression by using quantitative realtime polymerase chain reaction.

Results

Zinc supplementation induces gene expression of MT2A. Overall, a zinc dose-dependent induction of apoptosis under platin-based treatment could be observed. This effect could be verified in all analyzed cell lines in varying intensity.

Conclusions

MT expression is induced by zinc in a dose-dependent manner and inhibits a successful cisplatin therapy. Therefore, heavy metal exposure during cisplatin therapy, e.g., via cigarette smoke, might be an important factor. This should be considered in further therapeutic approaches.

One Third of Malignant Pleural Mesothelioma Shows High Immunohistochemical Expression of MSLN or CXCR4 Which Indicates Potent Candidates for Endo-Radiotherapy

Malignant pleural mesothelioma (MPM) is a mainly asbestos-related tumour associated with a very poor prognosis. Therapeutic approaches include multimodal therapy and chemotherapeutics, with cisplatin being the drug of choice, but response rates of only up to 14% indicate very poor outcomes. Effective treatment options are lacking. Besides the diagnostic usage of radioligands in positron emission tomography (PET)/computed tomography (CT), the endo-radioligand therapy with Lu177 has been proven as a powerful tool in cancer therapy. Mesothelin (MSLN) and C-XC chemokine receptor 4 (CXCR4) are membrane-bound proteins, expressed in certain cancers, and thus are promising targets for endo-radiotherapy. A significant portion of high MSLN- or CXCR4-expressing tumors within the MPM may open the field for this sophisticated treatment approach in the near future. Formalin-fixed, paraffin-embedded (FFPE) tumour specimens from 105 patients suffering from MPM and treated at the Lung Cancer Centre of Essen and at the Helios Klinikum Emil von Behring Berlin were screened. The tumour samples were arranged in tissue microarrays. We immunohistochemically stained the tumour samples against MSLN and CXCR4. The protein expressions of the stainings were scored by a pathologist by using a semiquantitative method. The data obtained were correlated with the clinical outcome. Overall, 77.1% of the analysed tumours showed CXCR4 protein expression (25.7% of them at high expression level (Score 3)). 48.6% of all samples showed an overall strong staining (Score ≥ 2), 59% of the investigated tumours showed MSLN protein expression (10.5% of them at high expression (Score 3)), and 36.2% of all samples showed an overall strong staining (Score ≥ 2). Our results show significant tissue expression levels, for both CXCR4 and MSLN protein, in a major portion of clinical MPM samples. One-third of patients showed outstanding immunoexpression of at least one of these markers, making them interesting candidates for radioligand-based PET/CT diagnostics and follow-up and furthermore may profit from endo-radiotherapy.

[Structured reporting of prostate cancer-self-development of a digital solution for prostate biopsies]

BACKGROUND

The challenges in pathology and in structuring of data are increasing. Although considerable amounts of data are generated during the pathological diagnostic process, these data are often not available in a structured form and have to be extracted from the reports through a time-consuming and error-prone manual approach. However, the data are required for various internal and external purposes, such as for audits, tumor organ centers, reporting to cancer registries, different consortia, billing, various aspects within the organization, and for research.

OBJECTIVES

The aim of the work was the development of a digital system for the direct and high-quality acquisition of structured pathology data using the example of biopsy-based diagnostics of prostate carcinoma.

MATERIALS AND METHODS

A solution was created in cooperation with the pathology laboratory information system (LIS) provider imassense GmbH (Berlin, Germany), whose LIS 'Informationssystem der digitalen Pathologie' (IS-P) is used at the Institute of Pathology at the University Hospital Essen.

RESULTS AND CONCLUSION

Over a period of about 1.5 years, a system that is capable of structured reporting according to local, national (S3 guidelines, German Cancer Society) and international (International Collaboration on Cancer Reporting [ICCR]) specifications was developed and subsequently used. The data are stored in readable databases and can easily be generated via IS‑P. Apart from the disadvantage of a highly specialized solution adapted to the LIS, the project also shows the feasibility in the local academic environment with the above-mentioned advantages.

Chronic Deciduitis With Plasma Cells: A Quantitative and Clinicopathological Analysis Concerning Different Trimesters

Background: Chronic deciduitis is a chronic inflammatory placental disease. It is associated with severe perinatal complications, especially recurrent miscarriage, preterm birth, preterm labor, and preterm prelabor rupture of membranes.Methods: This study presents a detailed quantification of plasma cells and lymphocytes, and regards clinicopathological associations concerning different trimesters in 99 cases displaying chronic deciduitis with plasma cells (CD), 23 cases from the second trimester and 76 cases from the third trimester, respectively. The control group without CD consisted of matched placentas concerning the gestational weeks.Results: In every instance lymphocytes were more numerous than plasma cells. The mean value/highest score in ten high power fields were 50/321 for plasma cells, and 460/995 for lymphocytes, respectively. In the second trimester the scores for plasma cells were significantly higher than in the third trimester. In the third trimester preterm labor occurred significantly more often in cases with chronic deciduitis related to the control group (P < .05).Conclusion: In chronic deciduitis the plasma cell count is usually higher in the second compared to the third trimester. A brisk infiltration of the decidua with plasma cells could probably point to a more severe clinical manifestation and a higher risk for preterm labor and preterm birth.

Knockout of Factor-Inhibiting HIF (Hif1an) in Colon Epithelium Attenuates Chronic Colitis but Does Not Reduce Colorectal Cancer in Mice

Inflammatory bowel disease such as chronic colitis promotes colorectal cancer, which is a common cause of cancer mortality worldwide. Hypoxia is a characteristic of inflammation as well as of solid tumors and enforces a gene expression response controlled by hypoxia-inducible factors (HIFs). Once established, solid tumors are immunosuppressive to escape their abatement through immune cells. Although HIF activity is known to 1) promote cancer development and 2) drive tumor immune suppression through the secretion of adenosine, both prolyl hydroxylases and an asparaginyl hydroxylase termed factor-inhibiting HIF (FIH) negatively regulate HIF. Thus, FIH may act as a tumor suppressor in colorectal cancer development. In this study, we examined the role of colon epithelial FIH in a mouse model of colitis-induced colorectal cancer. We recapitulated colitis-associated colorectal cancer development in mice using the azoxymethane/dextran sodium sulfate model in Vil1-Cre/FIH^+f/+f and wild-type siblings. Colon samples were analyzed regarding RNA and protein expression and histology. Vil1-Cre/FIH^+f/+f mice showed a less severe colitis progress compared with FIH^+f/+f animals and a lower number of infiltrating macrophages in the inflamed tissue. RNA sequencing analyses of colon tissue revealed a lower expression of genes associated with the immune response in Vil1-Cre/FIH^+f/+f mice. However, tumor occurrence did not significantly differ between Vil1-Cre/FIH^+f/+f and wild-type mice. Thus, FIH knockout in colon epithelial cells did not modulate colorectal cancer development but reduced the inflammatory response in chronic colitis.

Mitogen signal-associated pathways, energy metabolism regulation, and mediation of tumor immunogenicity play essential roles in the cellular response of malignant pleural mesotheliomas to platinum-based treatment: a retrospective study

Background

Malignant pleural mesothelioma (MPM) is a rare malignant tumor associated with asbestos exposure, with infaust prognosis and overall survival below 20 months in treated patients. Platinum is still the backbone of the chemotherapy protocols, and the reasons for the rather poor efficacy of platinum compounds in MPM remain largely unknown. Therefore, we aimed to analyze differences in key signaling pathways and biological mechanisms in therapy-naïve samples and samples after chemotherapy in order to evaluate the effect of platinum-based chemotherapy.

Methods

The study cohort comprised 24 MPM tumor specimens, 12 from therapy-naïve and 12 from patients after platinum-based therapy. Tumor samples were screened using the NanoString nCounter platform for digital gene expression analysis with an appurtenant custom-designed panel comprising a total of 366 mRNAs covering the most important tumor signaling pathways. Significant pathway associations were identified by gene set enrichment analysis using the WEB-based GEne SeT AnaLysis Toolkit (WebGestalt)

Results

We have found reduced activity of TNF (normalized enrichment score: 2.03), IL-17 (normalized enrichment score: 1.93), MAPK (normalized enrichment score: 1.51), and relaxin signaling pathways (normalized enrichment score: 1.42) in the samples obtained after platinum-based therapy. In contrast, AMPK (normalized enrichment score: –1.58), mTOR (normalized enrichment score: –1.50), Wnt (normalized enrichment score: –1.38), and longevity regulating pathway (normalized enrichment score: –1.31) showed significantly elevated expression in the same samples.

Conclusions

We could identify deregulated signaling pathways due to a directed cellular response to platinum-induced cell stress. Our results are paving the ground for a better understanding of cellular responses and escape mechanisms, carrying a high potential for improved clinical management of patients with MPM.

Pulmonary echinococcosis: A rare pseudotumour of the lung

Cystic echinococcosis is a widely endemic helminthic disease worldwide but occurs only rarely in Central Europe. Humans are infected as ‘aberrant’ hosts by Echinococcus granulosus and develop cysts in numerous different organs. 20%–30% of the affected individuals develop hydatid disease in the lungs with associated complications including pleuritis, lung abscess and pneumothorax. Radiologically, the pulmonary lesions of cystic echinococcosis occasionally pose difficulties in the differential diagnosis of primary lung carcinoma or metastatic disease and vice versa. Herein we report on a case of pulmonary hydatid disease in a 25-year-old Iraqi male presenting with a cystic lesion of the lung associated with thoracic pain and involuntary weight loss. Despite of its rare occurrence in Central Europe, clinicians, radiologists and pathologists should be aware of this entity and its pulmonary manifestations. During frozen section examination, imprint cytology specimens may facilitate the detection of the pathogens.

Digital Gene Expression Analysis of Epithelioid and Sarcomatoid Mesothelioma Reveals Differences in Immunogenicity

Malignant pleural mesothelioma (MPM) is an aggressive malignancy associated with asbestos exposure. Median survival ranges from 14 to 20 months after initial diagnosis. As of November 2020, the FDA approved a combination of immune checkpoint inhibitors after promising intermediate results. Nonetheless, responses remain unsatisfying. Adequate patient stratification to improve response rates is still lacking. This retrospective study analyzed formalin fixed paraffin embedded specimens from a cohort of 22 MPM. Twelve of those samples showed sarcomatoid, ten epithelioid differentiation. Complete follow-up, including radiological assessment of response by modRECIST and time to death, was available with reported deaths of all patients. RNA of all samples was isolated and subjected to digital gene expression pattern analysis. Our study revealed a notable difference between epithelioid and sarcomatoid mesothelioma, showing differential gene expression for 304/698 expressed genes. Whereas antigen processing and presentation to resident cytotoxic T cells as well as phagocytosis is highly affected in sarcomatoid mesothelioma, cell-cell interaction via cytokines seems to be of greater importance in epithelioid cases. Our work reveals the specific role of the immune system within the different histologic subtypes of MPM, providing a more detailed background of their immunogenic potential. This is of great interest regarding therapeutic strategies including immunotherapy in mesothelioma.

[Pulmonary lymphangioleiomyomatosis (LAM)]

Lymphangioleiomyomatosis (LAM) is a rare lung disease that mostly occurs in female patients. A total of 200-400 people are assumed to be infected in Germany. A sporadic form and a form associated with the tuberous sclerosis complex (TSC) can be separated. Mutations of the TSC‑1 and TSC‑2 genes are relevant. Morphologically, pulmonary multicysts and marginal micronodal proliferations of LAM cells are characteristic. Combinations with renal angiomyolipoma are typical and, in cases with TSC glioma, facial angiofibroma and ungual fibroma are seen. Prognosis is favorable (10-year survival: 80%) and with the use of mTORC1 inhibitors it could be improved. Lung transplantation can be considered in some cases.

[Mesothelial proliferation of the tunica vaginalis testis]

Proliferative changes seen in reactive mesothelial hyperplasia of a hydrocele sac may mimic malignant mesothelioma. There is no immunohistochemical staining that reliably separates benign from malignant mesothelial proliferations. However, the combined analysis of BAP1 by immunohistochemistry and CDKN2A by FISH has been reported to yield both a high specificity and sensitivity in this differential diagnosis. In addition, the evaluation of risk factors such as asbestos exposure or prior traumata may be helpful for the correct diagnosis. Exclusion of stromal invasion, which is diagnostic for malign mesothelioma, is of utmost importance. Therefore, extended histological workup is essential.

Machine learning reveals a PD-L1-independent prediction of response to immunotherapy of non-small cell lung cancer by gene expression context

OBJECTIVE

Current predictive biomarkers for PD-1 (programmed cell death protein 1)/PD-L1 (programmed death-ligand 1)-directed immunotherapy in non-small cell lung cancer (NSCLC) mostly focus on features of tumour cells. However, the tumour microenvironment and immune context are expected to play major roles in governing therapy response. Against this background, we set out to apply context-sensitive feature selection and machine learning approaches on expression profiles of immune-related genes in diagnostic biopsies of patients with stage IV NSCLC.

METHODS

RNA expression levels were determined using the NanoString nCounter platform in formalin-fixed paraffin-embedded tumour biopsies obtained during the diagnostic workup of stage IV NSCLC from two thoracic oncology centres. A 770-gene panel covering immune-related genes and control genes was used. We applied supervised machine learning methods for feature selection and generation of predictive models.

RESULTS

Feature selection and model creation were based on a training cohort of 55 patients with recurrent NSCLC treated with PD-1/PD-L1 antibody therapy. Resulting models identified patients with superior outcomes to immunotherapy, as validated in two subsequently recruited, separate patient cohorts (n = 67, hazard ratio = 0.46, p = 0.035). The predictive information obtained from these models was orthogonal to PD-L1 expression as per immunohistochemistry: Selecting by PD-L1 positivity at immunohistochemistry plus model prediction identified patients with highly favourable outcomes. Independence of PD-L1 positivity and model predictions were confirmed in multivariate analysis. Visualisation of the models revealed the predictive superiority of the entire 7-gene context over any single gene.

CONCLUSION

Using context-sensitive assays and bioinformatics capturing the tumour immune context allows precise prediction of response to PD-1/PD-L1-directed immunotherapy in NSCLC.

Prevalence of APC and PTEN Alterations in Urachal Cancer

Urachal carcinoma (UrC) is a rare tumor with remarkable histological and molecular similarities to colorectal cancer (CRC). Adenomatous polyposis coli (APC) is the most frequently affected gene in CRC, but the prevalence and significance of its alterations in UrC is poorly understood. In addition, loss of phosphatase and tensin homologue (PTEN) was shown to be associated with therapy resistance in CRC. Our primary aim was to assess specific genetic alterations including APC and PTEN in a large series of UrC samples in order to identify clinically significant genomic alterations. We analyzed a total of 40 UrC cases. Targeted 5-gene (APC, PTEN, DICER1, PRKAR1A, TSHR, WRN) panel sequencing was performed on the Illumina MiSeq platform (n = 34). In addition, ß-catenin (n = 38) and PTEN (n = 30) expressions were assessed by immunohistochemistry. APC and PTEN genes were affected in 15% (5/34) and 6% (2/34) of cases. Two of five APC alterations (p.Y1075*, p.K1199*) were truncating pathogenic mutations. One of the two PTEN variants was a pathogenic frameshift insertion (p.C211fs). In 29% (11/38) of samples, at least some weak nuclear ß-catenin immunostaining was detected and PTEN loss was observed in 20% (6/30) of samples. The low prevalence of APC mutations in UrC represents a characteristic difference to CRC. Based on APC and ß-catenin results, the Wnt pathway seems to be rarely affected in UrC. Considering the formerly described involvement of PTEN protein loss in anti-EGFR therapy-resistance its immunohistochemical testing may have therapeutic relevance.

The vascular nature of lung-resident mesenchymal stem cells

Human lungs bear their own reservoir of endogenous mesenchymal stem cells (MSCs). Although described as located perivascular, the cellular identity of primary lung MSCs remains elusive. Here we investigated the vascular nature of lung‐resident MSCs (LR‐MSCs) using healthy human lung tissue. LR‐MSCs predominately reside within the vascular stem cell niche, the so‐called vasculogenic zone of adult lung arteries. Primary LR‐MSCs isolated from normal human lung tissue showed typical MSC characteristics in vitro and were phenotypically and functionally indistinguishable from MSCs derived from the vascular wall of adult human blood vessels (VW‐MSCs). Moreover, LR‐MSCs expressed the VW‐MSC‐specific HOX code a characteristic to discriminate VW‐MSCs from phenotypical similar cells. Thus, LR‐MSC should be considered as VW‐MSCs. Immunofluorescent analyses of non‐small lung cancer (NSCLC) specimen further confirmed the vascular adventitia as stem cell niche for LR‐MSCs, and revealed their mobilization and activation in NSCLC progression. These findings have implications for understanding the role of MSC in normal lung physiology and pulmonary diseases, as well as for the rational design of additional therapeutic approaches.

Urachal Cancer in Germany and the USA: An RKI/SEER Population-Based Comparison Study

INTRODUCTION

Urachal cancer (UrC) is a rare but aggressive cancer. Due to its low incidence, structured epidemiological data have only rarely been reported. To date, no valid data on UrC are available for the German population.

METHODS

Data on incidence and relative 5-year survival of urachal lesions (ICD-10: C67.7) were collected from all population-based cancer registries in Germany, provided by the Robert Koch-Institut (RKI). Data were anonymized and included age, sex, and general histology (ICD-O-3). For comparison, a similar inquiry of the "Surveillance, Epidemiology, and End Results program" (SEER-18) database for the USA was conducted.

RESULTS

From 2011 to 2015, a total of 154 and 152 cases of UrC were reported for Germany (RKI) and the USA (SEER-18 area), respectively. Age-standardized incidence was 0.32/1,000,000 age-standardized cases/year in both cohorts, and elderly persons were more often affected. The major histological type was adenocarcinoma (64.9 and 81.6%). Relative 5-year survival was 54.8% (CI: 45.0-64.6) in Germany (RKI) and 64.4% (54.1-72.1) in the USA (SEER-18 cohort). Discusssion/Conclusion: The collected data demonstrate low incidence rates and similar epidemiological and clinicopathological characteristics of UrC for both registries. This is the first report of structured epidemiological data for UrC for the German population.

HDAC Inhibition Induces PD-L1 Expression in a Novel Anaplastic Thyroid Cancer Cell Line

While papillary thyroid cancer (PTC) has largely favorable prognosis, anaplastic thyroid cancer (ATC) is a rare but extremely aggressive malignancy with grim clinical outcome. Even though new therapeutic options are emerging for ATC, additional preclinical models and novel combinations are needed for specific subsets of patients. We established a novel cell line (PF49) from the malignant pleural effusion of a 68-year-old male patient with ATC that rapidly transformed from a BRAF and TERT promoter mutant PTC. PF49 cells demonstrated a robust migratory activity in vitro and strong invasive capacity in vivo in a pleural carcinosis model. Combined BRAF and MEK inhibition decreased the proliferation and migration of PF49 cells, however could not induce cell death. Importantly, HDAC inhibitor treatment with SAHA or valproic acid induced cell cycle arrest and strongly increased PD-L1 expression of the tumor cells. Induction of PD-L1 expression was also present when paclitaxel-cisplatin chemotherapeutic treatment was combined with HDAC inhibitor treatment. Increased PD-L1 expression after HDAC inhibition was recapitulated in an international ATC cell model. Our data suggest that HDAC inhibition alone or in combination with standard chemotherapy may potentiate anaplastic thyroid cancer cells for immunotherapy.

Volumetric PET Response Assessment Outperforms Conventional Criteria in Patients Receiving High-Dose Pembrolizumab for Malignant Mesothelioma

Fixed-dose pembrolizumab (200 mg absolute, day 1, every 3 wk) for the treatment of malignant pleural mesothelioma did not result in survival benefit in the phase 3 PROMISE-meso trial compared with second-line chemotherapy. Because of lack of validated imaging response criteria, responder subgroups with potential survival benefit have not yet been identified. Here, we administered high-dose pembrolizumab (10 mg/kg, day 1, every 2 wk) considering the KEYNOTE-028 trial and assessed the prognostic value of PET metabolic response in patients with chemotherapy-resistant malignant mesothelioma of the pleura or peritoneum. Methods: Data from 27 patients with baseline and follow-up ¹⁸F-FDG PET/CT imaging were retrospectively analyzed. RECIST, version 1.1; modified RECIST; and PERCIST using both tumor lesion metabolic activity in a 1 cm³ spheric region of interest of up to 5 target lesions (PERCIST_SULpeak) and metabolic tumor volume PERCIST (PERCIST_MTV) were applied separately to categorize responders in CT and PET imaging studies. Progression-free survival (PFS) and overall survival (OS) were compared between responders and nonresponders using Kaplan-Meier and log-rank analyses. Programmed cell death protein 1 ligand expression status was assessed, and its association with outcome was investigated. Results: Twenty-seven patients had ¹⁸F-FDG PET/CT imaging at baseline and after at least 4 cycles pembrolizumab. Median PFS and OS were 3.4 and 15.1 mo, respectively. Response rates were 7%, 7%, 30%, and 30% based on RECIST, modified RECIST, PERCIST_SULpeak, and PERCIST_MTV response criteria, respectively. Response according to PERCIST_MTV predicted prolonged OS or PFS (P < 0.01), whereas all other imaging criteria and programmed cell death protein 1 ligand expression did not. Conclusion: ¹⁸F-FDG PET metabolic volume response predicts survival in patients with malignant mesothelioma receiving high-dose pembrolizumab. These results should prompt inclusion of PET response assessment in future phase 3 clinical trials.

Tumour cell PD-L1 expression is prognostic in patients with malignant pleural effusion: the impact of C-reactive protein and immune-checkpoint inhibition

Malignant pleural effusion (MPE) confers dismal prognosis and has limited treatment options. While immune-checkpoint inhibition (ICI) proved clinical efficacy in a variety of malignancies, data on the prognostic role of PD-L1 in MPE is scarce. We retrospectively studied PD-L1 tumour proportion score and Ki-67 index in pleural biopsies or cytologies from 123 patients (69 lung cancer, 25 mesothelioma, and 29 extrathoracic primary malignancies). Additionally, the impact of C-reactive protein (CRP) and platelet count was also analysed. Median overall survival (OS) after MPE diagnosis was 9 months. Patients with PD-L1 positive tumours (≥1%) had significantly shorter OS than patients with negative PD-L1 status (p = 0.031). CRP and Ki-67 index were also prognostic and remained independent prognosticators after multivariate analysis. Interestingly, Ki-67 index and CRP influenced the prognostic power of PD-L1. Finally, patients receiving ICI tended to have a longer median OS and CRP - but not PD-L1 - was a significant prognosticator in this subgroup. In summary, histological and circulating biomarkers should also be taken into account as potential biomarkers in ICI therapy and they may have an impact on the prognostic power of PD-L1. Our findings might help personalizing immune-checkpoint inhibition for patients with MPE and warrant further prospective validation.

Intraoperative 68Ga-PSMA Cerenkov Luminescence Imaging for Surgical Margins in Radical Prostatectomy: A Feasibility Study

Our objective was to assess the feasibility and accuracy of Cerenkov luminescence imaging (CLI) for assessment of surgical margins intraoperatively during radical prostatectomy. Methods: A single-center feasibility study included 10 patients with high-risk primary prostate cancer (PC). ⁶⁸Ga-prostate-specific membrane antigen (PSMA) PET/CT scans were performed followed by radical prostatectomy and intraoperative CLI of the excised prostate. In addition to imaging the intact prostate, in the first 2 patients the prostate gland was incised and imaged with CLI to visualize the primary tumor. We compared the tumor margin status on CLI to postoperative histopathology. Measured CLI intensities were determined as tumor-to-background ratio. Results: Tumor cells were successfully detected on the incised prostate CLI images as confirmed by histopathology. Three of 10 men had histopathologically positive surgical margins (PSMs), and 2 of 3 PSMs were accurately detected on CLI. Overall, 25 (72%) of 35 regions of interest proved to visualize a tumor signal according to standard histopathology. The median tumor radiance in these areas was 11,301 photons/s/cm²/sr (range, 3,328-25,428 photons/s/cm²/sr), and median tumor-to-background ratio was 4.2 (range, 2.1-11.6). False-positive signals were seen mainly at the prostate base, with PC cells overlaid by benign tissue. PSMA immunohistochemistry revealed strong PSMA staining of benign gland tissue, which impacts measured activities. Conclusion: This feasibility showed that ⁶⁸Ga-PSMA CLI is a new intraoperative imaging technique capable of imaging the entire specimen's surface to detect PC tissue at the resection margin. Further optimization of the CLI protocol, or the use of lower-energy imaging tracers such as ¹⁸F-PSMA, is required to reduce false-positives. A larger study will be performed to assess diagnostic performance.

Integration of Bronchoscopic Transesophageal Ultrasound Examination of the Left Adrenal Gland into Routine Lung Cancer Staging Workup: A Prospective Trial

BACKGROUND

Endobronchial ultrasound (EBUS) with transbronchial needle aspiration increases the diagnostic yield of lung cancer staging. The left adrenal gland (LAG) is a common site for lung cancer metastasis. The modality of transesophageal examination with an EBUS bronchoscope (EUS-B) routinely for LAG has not been assessed.

OBJECTIVE

The aim of this study was to prospectively assess if evaluation and tissue sampling of the LAG could routinely be implemented in an EBUS procedure.

METHODS

Patients referred for EBUS between March and August 2017 had assessment of the LAG via EUS-B. Fine-needle aspiration (FNA) was performed in cases with a suspicious LAG. The detection rate, procedure time, and learning curve of four experienced EBUS-bronchoscopists was assessed, plus the diagnostic accuracy and complication rate of FNA.

RESULTS

In total, 313 consecutive patients were included. The overall LAG detection rate was 87.5%. After the initial learning curve, the detection rate for all four bronchoscopists was >93%. The detection rate did not correlate with any patient characteristics. EUS-B-FNA revealed nine LAG metastases, with a sensitivity, specificity, and accuracy of 75%, 100%, and 99%, respectively. The mean EUS-B operation time was 194.4 s, with 594.8 s for FNA. There were no FNA-associated complications.

CONCLUSIONS

Evaluation of the LAG with EUS-B could routinely be included in an EBUS procedure if necessary. A high detection rate can be achieved after an initial learning period. FNA of the LAG was feasible and safe. EUS-B of the LAG could be integrated into the usual EBUS/EUS-B procedure in lung cancer staging workup.

Prognostic significance of PD-1 and PD-L1 positive tumor-infiltrating immune cells in ovarian carcinoma

INTRODUCTION

Ovarian carcinoma is associated with the highest mortality of all gynecologic malignancies. Even after optimal treatment, prognosis remains poor. There is no established biomarker to predict individual patient outcome.

OBJECTIVE

To evaluate the prognostic significance of PD-1 and PD-L1 expression in tumor tissues from patients with ovarian cancer.

METHODS

Tissue micro-arrays were prepared from routinely formalin-fixed, paraffin-embedded tumor tissues and examined immunohistochemically for the expression of programed cell death protein 1 (PD-1) and one of its ligands (PD-L1) on epithelial tumor cells, as well as on tumor- and stroma-infiltrating immune cells.

RESULTS

The presence of PD-1 positive tumor-infiltrating immune cells was significantly associated with prolonged overall survival. PD-1 and PD-L1 positive tumor-infiltrating immune cells were associated with the presence of lymph node metastases and higher tumor grade. Interestingly, the amount of PD-1/PD-L1 positive tumor- and stroma-infiltrating immune cells independent of PD-1 or PD-L1 expression did not show any significant correlation with prognostic variables.

CONCLUSION

Our results highlight the prognostic value of PD-1 and PD-L1 positive tumor-infiltrating immune cells in ovarian carcinoma. Their association with favorable prognosis supports the hypothesis that the expression of PD-1 and PD-L1 on tumor-infiltrating immune cells represents a strong immune response.

A prospective comparison of growth patterns with radiomorphology in 232 lung metastases-basis for patient tailored resection planning?

Background

The histologic presence of aggressive local growth of pulmonary metastases is associated with an increased risk for local intrapulmonary recurrence after enucleation or wedge resection. Patient tailored resection planning is possible when morphologic pattern of aggressive growth could be identified based on preoperative CT scans.

Methods

Radiomorphology and microscopic growth characteristics from 232 pulmonary metastases from 87 patients were prospectively compared for the presence or absence of aggressive patterns of local intrapulmonary dissemination.

Results

Microscopic aggressive local growth was found: pleural involvement (18.5%), lymphatic invasion (6.9%), vascular invasion (7.3%), interstitial growth (38.4%), micro satellite nodules (24.5%), spread through air spaces (STAS) (13.4%), and a smooth, slightly blurred or irregular surface in 34.1%, 43.1% and 22.8%. The radiologic margin demarcation was smooth in 37.1%, blurred in 27.6% or irregular in 35.3% and spiculae were present in 26.3% of the lesions. The microscopic and radiologic description of the metastasis surface correlated well [correlation coefficient (CC) =0.75, P<0.001]. A smooth surface on CT scan corresponded with a smooth microscopic surface in 72/86 (83.7%) of the lesions. The radiomorphologic feature of an irregular or cloudy surface was highly associated with the presence of at least one aggressive pattern of local dissemination (P<0.001). The presence of spiculae on CT scan was well associated with the presence of aggressive local spread (P<0.001) and the microscopic features corresponding with spiculae were interstitial growth, STAS and L1.

Conclusions

Radiomorphologic characteristics of lung metastases correspond well with the microscopic appearance of the resected lesion. Therefore it seems possible to adjust safety margins based on the radiologic appearance of the metastasis.

Congenital Segmental Intestinal Dilatation: A 25-Year Review with Long-Term Follow-up at the Medical University of Innsbruck, Austria

Background and Aim  Congenital segmental intestinal dilatation (CSID) is a neonatal condition with unclear etiology and pathogenesis. Typically, the newborn with CSID presents with a limited (circumscribed) bowel dilatation, an abrupt transition between normal and dilated segments, neither intrinsic nor extrinsic perilesional obstruction, and no aganglionosis or neuronal intestinal dysplasia. We aimed to review this disease and the long-term follow-up at the Children's Hospital of the Medical University of Innsbruck, Tyrol, Austria. Study Design  Retrospective 25-year review of medical charts, electronic files, and histopathology of neonates with CSID. Results  We identified four infants (three girls and one boy) with CSID. The affected areas included duodenum, ileum, ascending colon, and sigmoid colon. Noteworthy, all patients presented with a cardiovascular defect, of which two required multiple cardiac surgical interventions. Three out of the four patients recovered completely. To date, the three infants are alive. Conclusion  This is the first report of patients with CSID and cardiovascular defects. The clinical and surgical intervention for CSID also requires a thorough cardiologic evaluation in these patients. CSID remains an enigmatic entity pointing to the need for joint forces in identifying common loci for genetic investigations.

Transbronchial cryobiopsy in fibrosing interstitial lung disease: modifications of the procedure lead to risk reduction

Sixty-one subjects with fibrosing interstitial lung disease were prospectively analysed to determine the efficacy of transbronchial cryobiopsy (CryoTBB) and the effect of procedural modifications which were introduced after an interim analysis of the first 19 subjects. The modifications significantly reduced complication rates from 84% to 14% (p<0.001). 30-day-mortality was 2%. The algorithm with initial CryoTBB and surgical lung biopsy (SLB) as optional step-up procedure was feasible. CryoTBB led to a confident diagnosis in 46/61 subjects (75%). Only 21% out of all subjects were forwarded for SLB. As the modified CryoTBB reduced but not eliminated the risk of severe complications, tissue sampling should be limited to patients where confident diagnosis enables life prolonging therapy. Trial registration number: NCT01714518.

Gene expression profiling of homologous recombination repair pathway indicates susceptibility for olaparib treatment in malignant pleural mesothelioma in vitro

BACKGROUND

Malignant pleural mesothelioma (MPM) is a tumour arising from pleural cavities with poor prognosis. Multimodality treatment with pemetrexed combined with cisplatin shows unsatisfying response-rates of 40%. The reasons for the rather poor efficacy of chemotherapeutic treatment are largely unknown. However, it is conceivable that DNA repair mechanisms lead to an impaired therapy response. We hypothesize a major role of homologous recombination (HR) for genome stability and survival of this tumour. Therefore, we analysed genes compiled under the term "BRCAness". An inhibition of this pathway with olaparib might abrogate this effect and induce apoptosis.

METHODS

We investigated the response of three MPM cell lines and lung fibroblasts serving as a control to treatment with pemetrexed, cisplatin and olaparib. Furthermore, we aimed to find possible correlations between response and gene expression patterns associated with BRCAness phenotype. Therefore, 91 clinical MPM samples were digitally screened for gene expression patterns of HR members.

RESULTS

A BRCAness-dependent increase of apoptosis and senescence during olaparib-based treatment of BRCA-associated-protein 1 (BAP1)-mutated cell lines was observed. The gene expression pattern identified could be found in approx. 10% of patient samples. Against this background, patients could be grouped according to their defects in the HR system. Gene expression levels of Aurora Kinase A (AURKA), RAD50 as well as DNA damage-binding protein 2 (DDB2) could be identified as prognostic markers in MPM.

CONCLUSIONS

Defects in HR compiled under the term BRCAness are a common event in MPM. The present data can lead to a better understanding of the underlaying cellular mechanisms and leave the door wide open for new therapeutic approaches for this severe disease with infaust prognosis. Response to Poly (ADP-ribose)-Polymerase (PARP)-Inhibition could be demonstrated in the BAP1-mutated NCI-H2452 cells, especially when combined with cisplatin. Thus, this combination therapy might be effective for up to 2/3 of patients, promising to enhance patients' clinical management and outcome.

Inhibition of Radiation-Induced Ccl2 Signaling Protects Lungs from Vascular Dysfunction and Endothelial Cell Loss

Aims: Radiation-induced normal tissue toxicity often precludes the application of curative radiation doses. Here we investigated the therapeutic potential of chemokine C-C motif ligand 2 (Ccl2) signaling inhibition to protect normal lung tissue from radiotherapy (RT)-induced injury. Results: RT-induced vascular dysfunction and associated adverse effects can be efficiently antagonized by inhibition of Ccl2 signaling using either the selective Ccl2 inhibitor bindarit (BIN) or mice deficient for the main Ccl2 receptor CCR2 (KO). BIN-treatment efficiently counteracted the RT-induced expression of Ccl2, normalized endothelial cell (EC) morphology and vascular function, and limited lung inflammation and metastasis early after irradiation (acute effects). A similar protection of the vascular compartment was detected by loss of Ccl2 signaling in lungs of CCR2-KO mice. Long-term Ccl2 signaling inhibition also significantly limited EC loss and accompanied fibrosis progression as adverse late effect. With respect to the human situation, we further confirmed that Ccl2 secreted by RT-induced senescent epithelial cells resulted in the activation of normally quiescent but DNA-damaged EC finally leading to EC loss in ex vivo cultured human normal lung tissue. Innovation: Abrogation of certain aspects of the secretome of irradiated resident lung cells, in particular signaling inhibition of the senescence-associated secretory phenotype-factor Ccl2 secreted predominantly by RT-induced senescent epithelial cells, resulted in protection of the endothelial compartment. Conclusions: Radioprotection of the normal tissue via Ccl2 signaling inhibition without simultaneous protection or preferable radiosensitization of tumor tissue might improve local tumor control and survival, because higher doses of radiation could be used.

Setting out the frame conditions for feasible use of FFPE derived RNA

INTRODUCTION

The usage of formalin-fixed paraffin embedded (FFPE) tissue is characterized by its long shelf-life and simple handling. Therefore it is the most commonly available tissue specimen in routine diagnostics and histological studies. Formaldehyde fixation may result in RNA degradation and cross linking with proteins, while storage conditions also affect RNA integrity. The present study was designed to investigate the influence of these factors on RNA analysis.

DESIGN

FFPE-derived RNA from sections of 23 patients with spontaneous pneumothoraxes was used. Unstained sections of FFPE tissue were stored at various temperatures (-80 °C, -20 °C, 4 °C, 24 °C) prior to RNA extraction. The potential impact on RNA quality of semi-automatic and manual RNA isolation and three different deparaffinization agents (mineral oil, xylene and d-limonene) were compared.

RESULTS

The storage temperature of FFPE sections affects RNA concentration and fragmentation, with the optimal storage temperature below -20 °C. The RNA extracted with d-limonene shows equivalent quality to the RNA extracted using more toxic standard agents. The manual isolation provides a higher RNA yield compared to the semi-automatic isolation. However, no differences in the amount of longer RNA fragments were observed. Furthermore, the semi-automatic isolation showed an enhanced RNA quality.

CONCLUSION

FFPE sections not directly used for RNA extraction should be stored below -20 °C to increase quality and yield of the RNA. Usage of semi-automatic isolation produces superior results and simplifies routine processes by having less hands-on-time. Replacement of toxic xylene by d-limonene may contribute to improved occupational safety while not influencing analytical results.

Growth patterns of pulmonary metastases: should we adjust resection techniques to primary histology and size?

OBJECTIVES

Safety margins in pulmonary metastasectomy are not yet well defined. We hypothesize that histological subtype, size of the lesion and local growth characteristics must be taken into consideration during metastasectomy. This study was conducted to examine and classify growth patterns at resection margins and define the relationships between aggressive local growth, metastasis size and local recurrence to direct metastasectomy.

METHODS

Histologic sections of pulmonary metastases were prospectively collected and haematoxylin-eosin stains were systematically evaluated and classified by their pattern of lung tissue infiltration. Logistic regression was used to model the association between the subgroups of colorectal, renal cell and epithelial cancers and melanomas and sarcomas.

RESULTS

From 183 patients, 412 lung specimens were removed, which contained 459 pulmonary metastases. We found that 58% of all lesions had microscopic signs of aggressive local dissemination. The metastases showed histology-specific patterns of local growth: sarcoma was associated with pleural infiltration; colorectal metastases with interstitial spread and aerogenous spread of floating cancer cell clusters; and melanoma with perivascular growth and with lymph vessel involvement. Aggressive patterns of growth had an increasing probability of around 3% for each additional millimetre of metastasis diameter. Local intrapulmonary recurrence was significantly more common in association with interstitial growth and pleural penetration as well as safety margins <7 mm.

CONCLUSIONS

Approximately 40% of all lung metastases have a smooth surface and might be resected with small margins. Growth characteristics within the lung differ with the histologic subtype and safety margins should generally increase with the size of the metastasis.

Immunohistochemically detectable metallothionein expression in malignant pleural mesotheliomas is strongly associated with early failure to platin-based chemotherapy

Background

Malignant pleural mesothelioma (MPM) is a biologically highly aggressive tumor arising from the pleura with a dismal prognosis. Cisplatin is the drug of choice for the treatment of MPM, and carboplatin seems to have comparable efficacy. Nevertheless, cisplatin treatment results in a response rate of merely 14% and a median survival of less than seven months. Due to their role in many cellular processes, methallothioneins (MTs) have been widely studied in various cancers. The known heavy metal detoxifying effect of MT-I and MT-II may be the reason for heavy metal drug resistance of various cancers including MPM.

Methods

105 patients were retrospectively analyzed immunohistochemically for their MT expression levels. Survival analysis was done by Cox-regression, and statistical significance determined using likelihood ratio, Wald test and Score (logrank) tests.

Results

Cox-regression analyses were done in a linear and logarithmic scale revealing a significant association between expression of MT and shortened overall survival (OS) in a linear (p=0.0009) and logarithmic scale (p=0.0003). Reduced progression free survival (PFS) was also observed for MT expressing tumors (linear: p=0.0134, log: p=0.0152).

Conclusion

Since both, overall survival and progression-free survival are negatively correlated with detectable MT expression in MPM, our results indicate a possible resistance to platin-based chemotherapy associated with MT expression upregulation, found exclusively in progressive MPM samples. Initial cell culture studies suggest promoter DNA hypomethylation and expression of miRNA-566 a direct regulator of copper transporter SLC31A1 and a putative regulator of MT1A and MT2A gene expression, to be responsible for the drug resistance.

MET Expression in Advanced Non-Small-Cell Lung Cancer: Effect on Clinical Outcomes of Chemotherapy, Targeted Therapy, and Immunotherapy

BACKGROUND

The receptor tyrosine kinase MET is implicated in malignant transformation, tumor progression, metastasis, and acquired treatment resistance. We conducted an analysis of the effect of MET expression and MET genomic aberrations on the outcome of patients with advanced or metastatic pulmonary adenocarcinomas prospectively enrolled in an institutional precision oncology program.

PATIENTS AND METHODS

Standardized immunohistochemistry (IHC) analyses of MET and markers of pathway activation were available in 384 patients, and next-generation sequencing-based MET hotspot mutation analyses were available from 892 patients. Clinical data were retrieved with a median follow-up from initial diagnosis of 37 months.

RESULTS

High MET expression, defined as MET IHC 3+ or MET H-Score in the upper quartile, was observed in 102 of 384 patients (26.6%). MET exon 14 mutations were only detected in 7 of 892 patients (0.78%). High MET expression correlated with activation markers of the mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) pathways only in cases without Kirsten rat sarcoma viral oncogene homolog (KRAS), epidermal growth factor receptor (EGFR), v-Raf murine sarcoma viral oncogene homolog B (BRAF), anaplastic lymphoma kinase (ALK) and proto-oncogene tyrosine-protein kinase ROS (ROS1) aberrations. There was no association of MET expression with outcome during chemotherapy. High MET expression negatively affected the outcome during EGFR-targeting therapy but was associated with more favorable results with programmed death 1/programmed death ligand 1 (PD-L1)-directed therapy, independent of smoking history, PD-L1 expression or KRAS mutation. Two patients with MET exon 14 mutation and high PD-L1 expression failed to respond to pembrolizumab.

CONCLUSION

MET expression affects the outcomes of targeted therapies in non-small-cell lung cancer, thus supporting the development of biomarker-informed combination strategies. The interaction of MET expression and MET mutation with immune checkpoint inhibitor therapy is novel and merits further investigation.

Folic-acid metabolism and DNA-repair phenotypes differ between neuroendocrine lung tumors and associate with aggressive subtypes, therapy resistance and outcome

Purpose

25% of all lung cancer cases are neuroendocrine (NELC) including typical (TC) and atypical carcinoid (AC), large-cell neuroendocrine (LCNEC) and small cell lung cancer (SCLC). Prognostic and predictive biomarkers are lacking.

Experimental Design

Sixty patients were used for nCounter mRNA expression analysis of the folic-acid metabolism (ATIC, DHFR, FOLR1, FPGS, GART, GGT1, SLC19A1, TYMS) and DNA-repair (ERCC1, MLH1, MSH2, MSH6, XRCC1). Phenotypic classification classified tumors (either below or above the median expression level) with respect to the folic acid metabolism or DNA repair.

Results

Expression of FOLR1, FPGS, MLH1 and TYMS (each p<0.0001) differed significantly between all four tumor types. FOLR1 and FPGS associated with tumor differentiation (both p<0.0001), spread to regional lymph nodes (FOLR1 p=0.0001 and FPGS p=0.0038), OS and PFS (FOLR1 p<0.0050 for both and FPGS p<0.0004 for OS).

Phenotypic sorting revealed the Ft-phenotype to be the most prominent expression profile in carcinoids, whereas SCLC presented nearly univocal with the fT and LCNEC with fT or ft. These results were significant for tumor subtype (p<0.0001).

Conclusions

The assessed biomarkers and phenotypes allow for risk stratification (OS, PFS), diagnostic classification and enhance the biological understanding of the different subtypes of neuroendocrine tumors revealing potential new therapy options and clarifying known resistance mechanisms.

Processing Escape Mechanisms Through Altered Proteasomal Cleavage of Epitopes Affect Immune Response in Pulmonary Neuroendocrine Tumors

Background:

Immunotherapy, especially immune checkpoint inhibition, is one of the most sophisticated approaches in cancer therapy. Immune checkpoint inhibition has already been successfully applied for treatment of non-small cell lung cancer and various other entities. Unfortunately, 60% of the cases show signs of therapy resistance. Additionally, a proportion of cases shows initial insensitivity to immune checkpoint inhibition. We consider a novel escape mechanism in association with deficient proteasomal epitope processing to be one prominent reason for initial insensitivity and therapy resistance. Therefore, we aim to identify mutations in association with these so-called processing escapes, in a highly diverse collective of pulmonary neuroendocrine lung tumors.

Materials and Methods:

Seventy representative tumor specimens of pulmonary neuroendocrine lung tumors were analyzed retrospectively via immunohistochemical detection of CD4, CD8, CD68, and CD20 as well as programmed cell death protein 1 and programmed cell death 1 ligand 1 for tumor immune infiltration and composition. Afterward, samples were screened for alterations in 48 genes, including 221 known mutational hotspots by massive parallel sequencing using the Illumina TruSeq Amplicon-Cancer Panel. For prediction of proteasomal cleavage probabilities, an R implementation of the machine learning tool NetChop 3.1 was utilized.

Results:

Immune cell infiltration of different compositions could be found in the majority of tumors. Deficient epitope processing was revealed to be a common event in those with steady distribution across all different subtypes. Despite immune infiltration, no significant antitumor response could be detected.

Conclusion:

Since it is widely acknowledged that tumors need to avoid the immune system to ensure their survival, processing escapes should already be present during primary tumor development. In line, processing escapes can be found in all tumors, regardless of subtype and mutational burden. Furthermore, there is solid evidence that processing escapes have a negative impact on the antitumor activity of tumor infiltrating immune cells.

Quantitative Analysis of Proteome Modulations in Alveolar Epithelial Type II Cells in Response to Pulmonary Aspergillus fumigatus Infection

The ubiquitous mold Aspergillus fumigatus threatens immunosuppressed patients as inducer of lethal invasive aspergillosis. A. fumigatus conidia are airborne and reach the alveoli, where they encounter alveolar epithelial cells (AEC). Previous studies reported the importance of the surfactant-producing AEC II during A. fumigatus infection via in vitro experiments using cell lines. We established a negative isolation protocol yielding untouched primary murine AEC II with a purity >90%, allowing ex vivo analyses of the cells, which encountered the mold in vivo By label-free proteome analysis of AEC II isolated from mice 24h after A. fumigatus or mock infection we quantified 2256 proteins and found 154 proteins to be significantly differentially abundant between both groups (ANOVA p value ≤ 0.01, ratio of means ≥1.5 or ≤0.67, quantified with ≥2 peptides). Most of these proteins were higher abundant in the infected condition and reflected a comprehensive activation of AEC II on interaction with A. fumigatus This was especially represented by proteins related to oxidative phosphorylation, hence energy production. However, the most strongly induced protein was the l-amino acid oxidase (LAAO) Interleukin 4 induced 1 (IL4I1) with a 42.9 fold higher abundance (ANOVA p value 2.91^-10). IL4I1 has previously been found in B cells, macrophages, dendritic cells and rare neurons. Increased IL4I1 abundance in AEC II was confirmed by qPCR, Western blot and immunohistology. Furthermore, A. fumigatus infected lungs showed high levels of IL4I1 metabolic products. Importantly, higher IL4I1 abundance was also confirmed in lung tissue from human aspergilloma. Because LAAO are key enzymes for bactericidal product generation, AEC II might actively participate in pathogen defense. We provide insights into proteome changes of primary AEC II thereby opening new avenues to analyze the molecular changes of this central lung cell on infectious threats. Data are available via ProteomeXchange with identifier PXD005834.

Sarcomatoid carcinoma of the lung: a rare histological subtype of non-small cell lung cancer with a poor prognosis even at earlier tumour stages

Objectives

Pulmonary sarcomatoid carcinoma (PSC) is a rare histological subtype of non-small cell lung cancer and comprises a diagnostically and therapeutically challenging group of tumours. We explored the clinicopathological features and prognostic factors of this tumour.

Methods

We conducted a retrospective study of all patients who were treated for PSC in the Department of Thoracic Surgery between May 2005 and December 2014. Primary outcomes of interest were patient survival and prognostic factors.

Results

A total of 58 patients were treated for sarcomatoid carcinoma within the described period and 46 patients underwent surgical resection with curative intent. The mean follow-up period was 30 months. Of the operated patients, 21.7% had pathological stage I disease, and 78.3% had more advanced disease. There were 25 carcinosarcomas, 10 pleomorphic carcinomas, 7 spindle cell carcinomas, 3 giant cell carcinomas and 1 pulmonary blastoma. Overall 5-year survival of the operated patients was 28.7%. A total of 28 patients experienced recurrence and died cancer-related. Our analysis revealed that tumour size, gender, histological entity, lymphatic vessel invasion (L1) and vascular invasion (V1) did not influence survival. There was a trend for decreased survival in older patients (>65 years).

Conclusions

Surgical treatment can achieve satisfactory results with low perioperative mortality, but the overall prognosis even with multimodality concepts and in earlier tumour stages is worse compared to other types of non-small cell lung cancer.

Migrating pleural plaque in a patient with asbestos induced pleural disease: a case report

Background

Health surveillance of formerly asbestos exposed individuals focus on early detection of asbestos related diseases, such as lung fibrosis (asbestosis), pleural plaques, mesothelioma and lung cancer in particular. One main concern is the early and clear identification of lesions with a high risk of malignant changes and their undelayed clinical work-up. False positive results may lead to unnecessary and often painful diagnostic interventions, which create high costs when applied to a large cohort and also may discredit the whole program. We describe an unusual presentation of a common lesion among asbestos exposed individuals, which has to our knowledge never been described before. Being aware of this pathological pathway may prevent inadequate clinical decisions with disadvantages for the patient. Underlying implications regarding health surveillance and the reading of CT-scans of the thorax are important for the management of formerly asbestos exposed individuals.

Case presentation

During follow-up of an asbestos exposed 72 year old former power plant worker with known pleural changes, a nodule located next to the left costophrenic angle was newly discovered on CT-scan. As the previous scan 1 year before did not show any changes in that area, a fast growing tumour was suspected and an immediate biopsy performed. The tissue showed the characteristics of a pleural plaque with no signs of malignancy. After carefully reviewing all previous radiographs a rounded opacity attached to the mediastinal pleura close to the oesophagus and slightly cranial to the position of the removed nodule could be discerned. That nodule had increased in size over several years and was no longer visible on the latest scan. It appeared that the originally slow growing plaque had migrated to the costophrenic angle some time before it was discovered in the latest scan thus imposing as a fast growing tumour.

Conclusions

We concluded that asbestos related pleural plaques can under special circumstances get separated from the pleura and migrate to another position in the pleural cavity. The case provides new insights in the development and properties of pleural lesions and may offer new options for the management of formerly asbestos exposed patients.

miRNA regulation is important for DNA damage repair and recognition in malignant pleural mesothelioma

Platin-containing regimes are currently considered as state-of-the-art therapies in malignant pleural mesotheliomas (MPM) but show dissatisfying response rates ranging from 6 to 16% only. Still, the reasons for the rather poor efficacy remain largely unknown. A clear stratification of patients based on new biomarkers seems to be a promising approach to enhance clinical management, which would be a long-needed improvement for MPM patients but does not seem likely soon unless new biomarkers can be validated. Twenty-four formalin-fixed, paraffin-embedded (FFPE) tumour specimens were subjected to a miRNA expression screening of 800 important miRNAs using digital quantification via the nCounter technique (NanoString). We defined a small subset of miRNAs regulating the key enzymes involved in the repair of platin-associated DNA damage. Particularly, the TP53 pathway network for DNA damage recognition as well as genes related to the term "BRCAness" are the main miRNA targets within this context. The TP53 pathway network for DNA damage recognition as well as genes related to the term "BRCAness" are the main players for risk stratification in patients suffering from this severe disease. Taking the specific molecular profile of the tumour into account can help to enhance the clinical management prospectively and to smooth the way to better response prediction.