HYAL2 methylation in peripheral blood as a potential marker for the detection of pancreatic cancer: a case control study

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy which is mostly diagnosed in advanced and inoperable stages though surgery remains the only curable therapeutic approach. Early detection markers are urgently needed to improve diagnosis. Altered hyaluronoglucosaminidase 2 gene (HYAL2) DNA methylation in peripheral blood is known to be associated with malignancy at early stage but has not been evaluated in PDAC patients. This study evaluates the association between blood-based HYAL2 methylation and PDAC by a case-control study with 191 controls and 82 PDAC patients. Decreased methylation of all four investigated HYAL2 methylation sites showed highly significant association with PDAC (odds ratio (ORs) per −10% methylation ranging from 2.03 to 12.74, depending on the specific CpG site, p < 0.0001 for all). HYAL2 methylation sites were also distinguishable between stage I&II PDAC (61 subjects) and controls (ORs per-10% methylation from 3.17 - 23.04, p < 0.0001 for all). Thus, HYAL2 methylation level enabled a very good discrimination of PDAC cases from healthy controls (area under curve (AUC) = 0.92, 95% Confidence interval (C.I.): 0.88 - 0.96), and was also powerful for the detection of PDAC at stage I&II (AUC = 0.93, 95% C.I.: 0.89 - 0.98). Moreover, the blood-based HYAL2 methylation pattern was similar among PDAC patients with differential clinical characteristics, and showed no correlation with the overall survival of PDAC patients. Our study reveals a strong association between decreased HYAL2 methylation in peripheral blood and PDAC, and provides a promising blood-based marker for the detection of PDAC.

The bile acid receptor FXR attenuates acinar cell autophagy in chronic pancreatitis

The functional relationship between bile acid (BA) and autophagy has not been evaluated in the context of pancreatitis. Here we investigated whether BA and their nuclear farnesoid X receptor (FXR) modulate autophagy and the development of pancreatitis. FXR expression, autophagy, apoptosis and necroptosis were determined in human chronic pancreatitis (CP) tissue in vivo and in pancreatic cells lines in vitro by means of real-time PCR, immunoblots and immunofluorescence. Pancreatic cell lines exposed to the most abundant BAs glycochenodeoxycholate (GCDC) and taurocholic acid (TCA) increased the expression of nuclear FXR and diminished that of the essential autophagy-related protein ATG7. BA was also elevated in pancreatic tissues from CP patients, correlating with elevated FXR and curtailed ATG7 expression with locally reduced autophagic activity. This was accompanied by an increased manifestation of CP hallmarks including apoptosis, necroptosis, inflammation and fibrosis. The present results suggest a cascade of events in which local accumulation of BA signals via FXR to suppress autophagy in pancreatic acinar cells, thereby unleashing acinar cell apoptosis and necroptosis. Thus, BA may cause CP by suppressing autophagy and exacerbating acinar cell apoptosis and necroptosis.

Induction of Chromosome Instability by Activation of Yes-Associated Protein and Forkhead Box M1 in Liver Cancer

BACKGROUND & AIMS

Many different types of cancer cells have chromosome instability. The hippo pathway leads to phosphorylation of the transcriptional activator yes-associated protein 1 (YAP1, YAP), which regulates proliferation and has been associated with the development of liver cancer. We investigated the effects of hippo signaling via YAP on chromosome stability and hepatocarcinogenesis in humans and mice.

METHODS

We analyzed transcriptome data from 242 patients with hepatocellular carcinoma (HCC) to search for gene signatures associated with chromosomal instability (CIN); we investigated associations with overall survival time and cancer recurrence using Kaplan-Meier curves. We analyzed changes in expression of these signature genes, at mRNA and protein levels, after small interfering RNA-mediated silencing of YAP in Sk-Hep1, SNU182, HepG2, or pancreatic cancer cells, as well as incubation with thiostrepton (an inhibitor of forkhead box M1 [FOXM1]) or verteporfin (inhibitor of the interaction between YAP and TEA domain transcription factor 4 [TEAD4]). We performed co-immunoprecipitation and chromatin immunoprecipitation experiments. We collected liver tissues from mice that express a constitutively active form of YAP (YAP^S127A) and analyzed gene expression signatures and histomorphologic parameters associated with chromosomal instability. Mice were given injections of thiostrepton and livers were collected and analyzed by immunoblotting, immunohistochemistry, histology, and real-time polymerase chain reaction. We performed immunohistochemical analyses on tissue microarrays of 105 HCCs and 7 nontumor liver tissues.

RESULTS

Gene expression patterns associated with chromosome instability, called CIN25 and CIN70, were detected in HCCs from patients with shorter survival time or early cancer recurrence. TEAD4 and YAP were required for CIN25 and CIN70 signature expression via induction and binding of FOXM1. Disrupting the interaction between YAP and TEAD4 with verteporfin, or inhibiting FOXM1 with thiostrepton, reduced the chromosome instability gene expression patterns. Hyperplastic livers and tumors from YAP^S127A mice had increased CIN25 and CIN70 gene expression patterns, aneuploidy, and defects in mitosis. Injection of YAP^S127A mice with thiostrepton reduced liver overgrowth and signs of chromosomal instability. In human HCC tissues, high levels of nuclear YAP correlated with increased chromosome instability gene expression patterns and aneuploidy.

CONCLUSIONS

By analyzing cell lines, genetically modified mice, and HCC tissues, we found that YAP cooperates with FOXM1 to contribute to chromosome instability. Agents that disrupt this pathway might be developed as treatments for liver cancer. Transcriptome data are available in the Gene Expression Omnibus public database (accession numbers: GSE32597 and GSE73396).

Spatial intratumoral heterogeneity of proliferation in immunohistochemical images of solid tumors

PURPOSE

The interactions of neoplastic cells with each other and the microenvironment are complex. To understand intratumoral heterogeneity, subtle differences should be quantified. Main factors contributing to heterogeneity include the gradient ischemic level within neoplasms, action of microenvironment, mechanisms of intercellular transfer of genetic information, and differential mechanisms of modifications of genetic material/proteins. This may reflect on the expression of biomarkers in the context of prognosis/stratification. Hence, a rigorous approach for assessing the spatial intratumoral heterogeneity of histological biomarker expression with accuracy and reproducibility is required, since patterns in immunohistochemical images can be challenging to identify and describe.

METHODS

A quantitative method that is useful for characterizing complex irregular structures is lacunarity; it is a multiscale technique that exhaustively samples the image, while the decay of its index as a function of window size follows characteristic patterns for different spatial arrangements. In histological images, lacunarity provides a useful measure for the spatial organization of a biomarker when a sampling scheme is employed and relevant features are computed. The proposed approach quantifies the segmented proliferative cells and not the textural content of the histological slide, thus providing a more realistic measure of heterogeneity within the sample space of the tumor region. The aim is to investigate in whole sections of primary pancreatic neuroendocrine neoplasms (pNENs), using whole-slide imaging and image analysis, the spatial intratumoral heterogeneity of Ki-67 immunostains. Unsupervised learning is employed to verify that the approach can partition the tissue sections according to distributional heterogeneity.

RESULTS

The architectural complexity of histological images has shown that single measurements are often insufficient. Inhomogeneity of distribution depends not only on percentage content of proliferation phase but also on how the phase fills the space. Lacunarity curves demonstrate variations in the sampled image sections. Since the spatial distribution of proliferation in each case is different, the width of the curves changes too. Image sections that have smaller numerical variations in the computed features correspond to neoplasms with spatially homogeneous proliferation, while larger variations correspond to cases where proliferation shows various degrees of clumping. Grade 1 (uniform/nonuniform: 74%/26%) and grade 3 (uniform: 100%) pNENs demonstrate a more homogeneous proliferation with grade 1 neoplasms being more variant, while grade 2 tumor regions render a more diverse landscape (50%/50%). Hence, some cases show an increased degree of spatial heterogeneity comparing to others with similar grade. Whether this is a sign of different tumor biology and an association with a more benign/malignant clinical course needs to be investigated further. The extent and range of spatial heterogeneity has the potential to be evaluated as a prognostic marker.

CONCLUSIONS

The association with tumor grade as well as the rationale that the methodology reflects true tumor architecture supports the technical soundness of the method. This reflects a general approach which is relevant to other solid tumors and biomarkers. Drawing upon the merits of computational biomedicine, the approach uncovers salient features for use in future studies of clinical relevance.

Paraganglioma of the Seminal Vesicle Case Report and Review of the Literature

Background: The present case report describes an extremely rare case of a norepinephrine secreting extraadrenal paraganglioma (PGL) located in the seminal vesicle.

Case Presentation: A 36-year-old patient had signs of intermittent hypertensive derailments, bradycardia, increased norepinephrine excretion in 24-hour urine, an increased metanephrine plasma concentration, and a positive clonidine suppression test. A suspicious mass was detected in an (18)F-DOPA-PET/CT-scan in the left seminal vesicle. Following adrenergic blockade, a robotically assisted laparoscopic left vesiculectomy with negative soft tissue surgical margins was performed. The patient sustained a couple of few months of voiding difficulties of the lower urinary tract and obstruction of the left upper urinary tract after the surgery, which resolved spontaneously with home medical treatment. Two years after the initial treatment, the patient relapsed, which was confirmed by endocrinologic follow-up tests with increased urine catecholamine, a positive clonidine suppression test, as well as an elevated blood pressure. Staging with (18)F-DOPA-PET/CT-scan confirmed the diagnosis of a recurrent PGL. This was followed by subsequent open surgical removal of the suspicious lesion in the seminal fossa. The patient is still recurrence free 15 months after the second surgery. Complications after the second surgery included an intermittent paresthesia of the left leg lasting 3 to 4 months. No other urologic symptoms such as voiding or erectile dysfunction occurred.

Conclusion: DaVinci-assisted laparoscopic vesiculectomy is a viable procedure to treat such cases providing satisfactory results. Relevant for clinical practice are the regular and lifelong follow-up examinations to detect recurrences.

Abstract B34: A Novel MIF-driven Signaling Drives Disease Aggressiveness by Targeting NR3C2 in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is a lethal malignancy. Pancreatic tumors with aberrant expression of macrophage migration inhibitory factor (MIF) are highly aggressive, and an increased MIF predicts poorer patient survival. We analyzed the expression of coding and non-coding genes in high and low MIF-expressing tumors in multiple cohorts of PDAC patients to identify key signaling pathways that drive disease aggressiveness in tumors with high MIF expression. The identified key genes and pathways were linked to patients’ survival and were mechanistically, functionally and clinically characterized using cell lines, genetically engineered mouse model and PDAC patient cohorts. Here, we report mechanistic, functional and clinical evidence of a novel MIF-driven signaling pathway that inhibits a previously undescribed tumor suppressor, nuclear-receptor-subfamily-3, group-C, member-2 (NR3C2), leading to enhanced disease aggressiveness and poorer survival in PDAC. MIF upregulated miR-301b, which then targeted and suppressed NR3C2 expression. Tumors with high MIF expression showed an elevated miR-301b and a reduced NR3C2 expression. Additionally, patients with a lower NR3C2 expression in tumors showed poorer survival in multiple independent cohorts of PDAC patients. NR3C2 inhibited epithelial-to-mesenchymal transition and enhanced sensitivity to chemotherapeutic drug gemcitabine. Furthermore, genetic deletion of MIF disrupted MIF-mir-301b-NR3C2 axis, which resulted in reduced metastasis and prolonged survival in genetically engineered mouse model of PDAC. These findings provide proof-of-principle that therapies targeting MIF-miR-301b-NR3C2 axis may improve disease outcome in PDAC

Citation Format: Shouhui Yang, Peijun He, Jian Wang, Aaron Schetter, Wei Tang, Naotake Funamizu, Katsuhiko Yanaga, Tadashi Uwagawa, Abhay R. Satoskar, Jochen Gaedcke, Markus Bernhardt, B. Michael Ghadimi, Matthias M. Gaida, Frank Bergmann, Jens Werner, Thomas Ried, Nader Hanna, H. Richard Alexander, S. Perwez Hussain.{Authors}. A Novel MIF-driven Signaling Drives Disease Aggressiveness by Targeting NR3C2 in Pancreatic Cancer. [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2016 May 12-15; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2016;76(24 Suppl):Abstract nr B34.

Enucleation: A treatment alternative for branch duct intraductal papillary mucinous neoplasms

BACKGROUND

Small, asymptomatic, branch-duct intraductal papillary mucinous neoplasms of the pancreas are often kept under surveillance despite their malignant potential. The management of branch-duct intraductal papillary mucinous neoplasm is controversial with regard to indications and extent of any operative intervention. The present study aimed to evaluate enucleation as an alternative operative approach for branch-duct intraductal papillary mucinous neoplasms to exclude and prevent malignancy.

METHODS

For branch-duct intraductal papillary mucinous neoplasms of <30 mm in diameter and an acceptable distance from the main pancreatic duct, enucleation was considered as the operative approach of choice. All patients scheduled for enucleation of branch-duct intraductal papillary mucinous neoplasm on the basis of these features between January 2004 and September 2014 were analyzed. Among these, patients with successful enucleation were compared with those who were scheduled for enucleation but converted intraoperatively to pancreatic resection (intention-to-treat analysis). End points were hospital morbidity and mortality as well as histopathology and functional outcome at a mean follow-up of 32 months.

RESULTS

In the study, 115 patients with presumed branch-duct intraductal papillary mucinous neoplasm and the intention to perform pancreatic enucleation were included; 87 enucleations were performed in 74 patients. In 41 patients, enucleation was converted to a pancreatic resection (procedure-specific success rate 64%); indications for conversion included location or size (46%), presence of multicystic lesions (39%), or involvement of the main pancreatic duct (15%). Of the 74 patients with enucleation, 64 branch-duct intraductal papillary mucinous neoplasms revealed low- (85%), 11% moderate dysplasia-, and 4% high-grade dysplasia on histology. Among converted resections, 6 intraductal papillary mucinous neoplasms revealed high-grade dysplasia or invasive carcinoma (15%). Intention-to-treat analysis with patients converted to pancreatic resection showed that enucleations resulted in less blood loss (100 vs 400 mL) and a shorter operation time (146 vs 255 minutes; P < .001 each). Postoperative morbidity including postoperative pancreatic fistula was similar in both groups. No mortality occurred after enucleation; after formal resection, 1 patient died due to multiorgan failure. Both hospital stay (10 vs 14 days) and rates of postoperative endocrine and exocrine dysfunction rates were less after enucleation (P < .02 each). Intraductal papillary mucinous neoplasm-specific recurrence rates (3% vs 6%) were similar in both groups.

CONCLUSION

Enucleation is a safe procedure that can be performed successfully in a high proportion of branch-duct intraductal papillary mucinous neoplasms and should be considered instead of standard resections as an important function-preserving alternative. Limitations may occur due to malignancy, size, localization, multilocularity, or main-duct involvement requiring conversion to a formal, anatomic resection. Beside the advantages in the short-term course, functional outcome seems to be superior after enucleation, and intraductal papillary mucinous neoplasm-specific recurrence rates are not increased compared with standard resections, at least at a mean follow-up of 32 months.

[Pancreatic acinar neoplasms : Comparative molecular characterization]

Pancreatic acinar cell carcinomas are biologically aggressive neoplasms for which treatment options are very limited. The molecular mechanisms of tumor initiation and progression are largely not understood and precursor lesions have not yet been identified. In this study, pancreatic acinar cell carcinomas were cytogenetically characterized as well as by molecular and immunohistochemical analyses. Corresponding investigations were carried out on pancreatic ductal adenocarcinomas and pancreatic neuroendocrine neoplasms augmented by functional analyses. We show that pancreatic acinar cell carcinomas display a microsatellite stable, chromosomal unstable genotype, characterized by recurrent chromosomal imbalances that clearly discriminate them from pancreatic ductal adenocarcinomas and neuroendocrine neoplasms. Based on findings obtained from comparative genomic hybridization, candidate genes could be identified, such as deleted in colorectal cancer (DCC) and c-MYC. Furthermore, several therapeutic targets were identified in acinar cell carcinomas and other pancreatic neoplasms, including epidermal growth factor receptor (EGFR), L1 cell adhesion molecule (L1CAM) and heat shock protein 90 (HSP90). Moreover, L1CAM was shown to play a significant role in the tumorigenesis of pancreatic ductal adenocarcinoma. Functional analyses in cell lines derived from pancreatic neuroendocrine neoplasms revealed promising anti-tumorigenic effects using EGFR and HSP90 inhibitors affecting the cell cycle and in the case of HSP90, regulating several other oncogenes. Finally, based on mutational analyses of mitochondrial DNA, molecular evidence is provided that acinar cell cystadenomas (or better cystic acinar transformation) represent non-clonal lesions, suggesting an inflammatory reactive non-neoplastic nature.

Epithelial to Stromal Re-Distribution of Primary Cilia during Pancreatic Carcinogenesis

Background

The Hedgehog (HH) pathway is a mediator in pancreatic ductal adenocarcinoma (PDAC). Surprisingly, previous studies suggested that primary cilia (PC), the essential organelles for HH signal transduction, were lost in PDAC. The aim of this study was to determine the presence of PC in human normal pancreas, chronic pancreatitis, and during carcinogenesis to PDAC with focus on both epithelia and stroma.

Methods

PC were analyzed in paraffin sections from normal pancreas, chronic pancreatitis, intraductal papillary-mucinous neoplasia, and PDAC, as well as in primary human pancreatic stellate cells (PSC) and pancreatic cancer cell lines by double immunofluorescence staining for acetylated α-tubuline and γ-tubuline. Co-staining for the HH receptors PTCH1, PTCH2 and SMO was also performed.

Results

PC are gradually lost during pancreatic carcinogenesis in the epithelium: the fraction of cells with PC gradually and significantly decreased from 32% in ducts of normal pancreas, to 21% in ducts of chronic pancreatitis, to 18% in PanIN1a, 6% in PanIN2, 3% in PanIN3 and to 1.2% in invasive PDAC. However, this loss of PC in the neoplastic epithelium is accompanied by a gain of PC in the surrounding stroma. The fraction of stromal cells with PC significantly increased from 13% around normal ducts to about 30% around PanIN and PDAC. HH-receptors were detected in tumor stroma but not in epithelial cells. PC are also present in PSC and pancreatic cancer cell lines.

Conclusion

PC are not lost during pancreatic carcinogenesis but re-distributed from the epithelium to the stroma. This redistribution may explain the re-direction of HH signaling towards the stroma during pancreatic carcinogenesis.

Identification of a tumor-reactive T-cell repertoire in the immune infiltrate of patients with resectable pancreatic ductal adenocarcinoma

PURPOSE

The devastating prognosis of patients with resectable pancreatic ductal adenocarcinoma (PDA) presents an urgent need for the development of therapeutic strategies targeting disseminated tumor cells. Until now, T-cell therapy has been scarcely pursued in PDA, due to the prevailing view that it represents a poorly immunogenic tumor.

EXPERIMENTAL DESIGN

We systematically analyzed T-cell infiltrates in tumor biopsies from 127 patients with resectable PDA by means of immunohistochemistry, flow cytometry, T-cell receptor (TCR) deep-sequencing and functional analysis of in vitro expanded T-cell cultures. Parallel studies were performed on tumor-infiltrating lymphocytes (TIL) from 44 patients with metastatic melanoma.

RESULTS

Prominent T-cell infiltrates, as well as tertiary lymphoid structures harboring proliferating T-cells, were detected in the vast majority of biopsies from PDA patients. The notion that the tumor is a site of local T-cell expansion was strengthened by TCR deep-sequencing, revealing that the T-cell repertoire in the tumor is dominated by highly frequent CDR3 sequences that can be up to 10,000-fold enriched in tumor as compared to peripheral blood. In fact, TCR repertoire composition in PDA resembled that in melanoma. Moreover, in vitro expansion of TILs was equally efficient for PDA and melanoma, resulting in T-cell cultures displaying HLA class I-restricted reactivity against autologous tumor cells.

CONCLUSIONS

The tumor-infiltrating T-cell response in PDA shows striking similarity to that in melanoma, where adoptive T-cell therapy has significant therapeutic impact. Our findings indicate that T-cell-based therapies may be used to counter disease recurrence in patients with resectable PDA.

Integrating highly quantitative proteomics and genome-scale metabolic modeling to study pH adaptation in the human pathogen Enterococcus faecalis

Genome-scale metabolic models represent the entirety of metabolic reactions of an organism based on the annotation of the respective genome. These models commonly allow all reactions to proceed concurrently, disregarding the fact that at no point all proteins will be present in a cell. The metabolic reaction space can be constrained to a more physiological state using experimentally obtained information on enzyme abundances. However, high-quality, genome-wide protein measurements have been challenging and typically transcript abundances have been used as a surrogate for protein measurements. With recent developments in mass spectrometry-based proteomics, exemplified by SWATH-MS, the acquisition of highly quantitative proteome-wide data at reasonable throughput has come within reach. Here we present methodology to integrate such proteome-wide data into genome-scale models. We applied this methodology to study cellular changes in Enterococcus faecalis during adaptation to low pH. Our results indicate reduced proton production in the central metabolism and decreased membrane permeability for protons due to different membrane composition. We conclude that proteomic data constrain genome-scale models to a physiological state and, in return, genome-scale models are useful tools to contextualize proteomic data.

Efficacy of topotecan in pretreated metastatic poorly differentiated extrapulmonary neuroendocrine carcinoma

Therapeutic options for metastatic poorly differentiated neuroendocrine carcinoma (NEC) after prior platinum-based chemotherapy are limited. Topotecan is an approved second-line chemotherapy for small cell lung cancer (SCLC). NEC is often considered to show a biological behavior similar to SCLC. The aim of this study was to analyze the efficacy of topotecan in pretreated metastatic NEC patients. We performed a retrospective analysis of all patients treated with topotecan for metastatic NEC who presented at our center between January 2005 and December 2014 (n = 30). All 30 patients had received at least a platinum and etoposide containing regimen as prior chemotherapy. Median proliferation rate (Ki67) was 80%. As best response to topotecan five patients showed a stable disease, two patients a partial remission, resulting in a disease control rate of 23%. Of the remaining 23 patients, 14 (47%) showed a progressive disease, nine (30%) died before radiologic response could be evaluated. Median progression-free (PFS) and overall survival (OS) after start of topotecan was 2.1 and 4.1 months, respectively. In the subgroup analysis, patients with unknown primary (vs. those with a known primary) showed a significantly prolonged PFS of 3.5 months (vs. 1.9, P = 0.0107) and OS of 6.7 months (vs. 2.6 months, P = 0.0168). Grade 3/4 hematotoxicity was observed in 60% of patients. Topotecan shows only moderate antitumor activity in metastatic NEC. Disease control rate is lower than reported for SCLC. However, antitumor activity of topotecan seems higher in patients with unknown primary.

A Novel MIF Signaling Pathway Drives the Malignant Character of Pancreatic Cancer by Targeting NR3C2

Pancreatic cancers with aberrant expression of macrophage migration inhibitory factor (MIF) are particularly aggressive. To identify key signaling pathways that drive disease aggressiveness in tumors with high MIF expression, we analyzed the expression of coding and noncoding genes in high and low MIF-expressing tumors in multiple cohorts of pancreatic ductal adenocarcinoma (PDAC) patients. The key genes and pathways identified were linked to patient survival and were mechanistically, functionally, and clinically characterized using cell lines, a genetically engineered mouse model, and PDAC patient cohorts. Here, we report evidence of a novel MIF-driven signaling pathway that inhibits the orphan nuclear receptor NR3C2, a previously undescribed tumor suppressor that impacts aggressiveness and survival in PDAC. Mechanistically, MIF upregulated miR-301b that targeted NR3C2 and suppressed its expression. PDAC tumors expressing high levels of MIF displayed elevated levels of miR-301b and reduced levels of NR3C2. In addition, reduced levels of NR3C2 expression correlated with poorer survival in multiple independent cohorts of PDAC patients. Functional analysis showed that NR3C2 inhibited epithelial-to-mesenchymal transition and enhanced sensitivity to the gemcitabine, a chemotherapeutic drug used in PDAC standard of care. Furthermore, genetic deletion of MIF disrupted a MIF-mir-301b-NR3C2 signaling axis, reducing metastasis and prolonging survival in a genetically engineered mouse model of PDAC. Taken together, our results offer a preclinical proof of principle for candidate therapies to target a newly described MIF-miR-301b-NR3C2 signaling axis for PDAC management. Cancer Res; 76(13); 3838-50. ©2016 AACR.

Intraductal papillary mucinous neoplasms of the pancreas: radiological predictors of malignant transformation and the introduction of bile duct dilation to current guidelines

OBJECTIVE

To evaluate the current guidelines as a model to predict malignancy and to determine further radiological predictors of malignancy in intraductal papillary mucinous neoplasms (IPMNs).

METHODS

384 patients who had undergone a pancreatic operation with the pathological diagnosis of IPMN as well as applicable pre-operative imaging (CT/MRI) were included in the study. Images were evaluated retrospectively in consensus by two radiologists, using a standardized checklist. Descriptive statistics, binary logistic regression and receiver operator curve analysis were performed to assess the International Consensus Guidelines and other radiological predictors of clinical malignancy (defined as carcinoma in situ and invasive carcinoma).

RESULTS

The best independent predictors of malignancy (n = 191) were solid components [odds ratio (OR) 3.98], parenchymal atrophy with main pancreatic duct dilation 5-9 mm (OR: 5.1) and common bile duct (CBD) dilation (OR: 31.26). >96% of all cases with CBD dilation were malignant IPMNs (positive-predictive value 96.4%; negative-predictive value 63.1%). Analysis of the current guidelines showed a diagnostic improvement with the addition of CBD dilation on determining the malignancy of IPMNs (sensitivity 82.2%/86.9%; specificity 72.7%/74.6%). Subanalysis of branch duct intraductal papillary mucinous neoplasms (BD-IPMNs; n = 168) also resulted in a diagnostic improvement with the addition of CBD dilation (sensitivity 28.6%/45.2%; specificity 92.9%/92.1%). The best independent predictors of malignancy for BD-IPMNs were parenchymal atrophy (OR: 4.00) and CBD dilation (OR: 29.3). Frequency analysis revealed that even small BD-IPMNs had already undergone malignant transformation (≤1 cm: 15%; 1-2 cm: 26%; 2-3 cm: 20%) with about 10% of those having a dilated bile duct.

CONCLUSION

CBD dilation was a significant positive predictor of malignancy in IPMNs regardless of their size.

ADVANCES IN KNOWLEDGE

Introduction of CBD dilation as a radiological predictor for malignancy might increase the diagnostic accuracy of current imaging-based guidelines.

Image-defined Risk Factors Correlate with Surgical Radicality and Local Recurrence in Patients with Neuroblastoma

BACKGROUND

Neuroblastoma is the second most common solid pediatric tumor and the most common cancer to be detected in children younger than 12 months of age. To date, 2 different staging systems describe the extent of the disease: the International Neuroblastoma Staging System (INSS) and the International Neuroblastoma Risk Group Staging System (INRGSS). The INRGSS-system is characterized by the presence or absence of so called image-defined risk factors (IDRFs), which are described as surgical risk factors. We hypothesized that IDRFs correlate with surgical complications, surgical radicality, local recurrence and overall survival (OS).

PATIENTS AND METHODS

Between 2003 and 2010, 102 patients had neuroblastoma surgery performed in our department. We analyzed medical records for IDRF-status and above named data.

RESULTS

16 patients were IDRF-negative, whereas 86 patients showed one or more IDRF. Intra- or postoperative complications have been reported in 21 patients (21%). 19 of them showed one or more IDRF and 2 patients were IDRF-negative (p=n.s.). Patients who suffered from intra- or postoperative complications demonstrated a decreased OS (p=0.011). Statistical analysis revealed an inverse correlation between the extent of macroscopical removal and IDRF-status (p=0.001). Furthermore, the number of IDRFs were associated with a decreased likelihood of radical tumor resection (p<0.001). 19 patients had local recurrence; all of them were IDRF-positive (p=0.037).

CONCLUSIONS

Pediatric surgeons should consider IDRFs as a useful tool for risk assessment and therefore planning for neuroblastoma surgery.

Tipranavir/Ritonavir (500/200 mg and 500/100 mg) Was Virologically Non-Inferior to Lopinavir/Ritonavir (400/100 mg) at Week 48 in Treatment-Naïve HIV-1-Infected Patients: A Randomized, Multinational, Multicenter Trial

Ritonavir-boosted tipranavir (TPV/r) was evaluated as initial therapy in treatment-naïve HIV-1-infected patients because of its potency, unique resistance profile, and high genetic barrier. Trial 1182.33, an open-label, randomized trial, compared two TPV/r dose combinations versus ritonavir-boosted lopinavir (LPV/r). Eligible adults, who had no prior antiretroviral therapy were randomized to twice daily (BID) 500/100 mg TPV/r, 500/200 mg TPV/r, or 400/100 mg LPV/r. Each treatment group also received Tenofovir 300 mg + Lamivudine 300 mg QD. The primary endpoint was a confirmed viral load (VL) <50 copies/mL at week 48 without prior antiretroviral regimen changes. Primary analyses examined CD4-adjusted response rates for non-inferiority, using a 15% non-inferiority margin. At week 48, VL<50 copies/mL was 68.4%, 69.9%, and 72.4% in TPV/r100, TPV/r200, and LPV/r groups, respectively, and TPV/r groups showed non-inferiority to LPV/r. Discontinuation due to adverse events was higher in TPV/r100 (10.3%) and TPV/r200 (15.3%) recipients versus LPV/r (3.2%) recipients. The frequency of grade ≥3 transaminase elevations was higher in the TPV/r200 group than the other groups, leading to closure of this group. However, upon continued treatment or following re-introduction after treatment interruption, transaminase elevations returned to grade ≤2 in >65% of patients receiving either TPV/r200 or TPV/r100. The trial was subsequently discontinued; primary objectives were achieved and continuing TPV/r100 was less tolerable than standard of care for initial highly active antiretroviral therapy. All treatment groups had similar 48-week treatment responses. TPV/r100 and TPV/r200 regimens resulted in sustained treatment responses, which were non-inferior to LPV/r at 48 weeks. When compared with the LPV/r regimen and examined in the light of more current regimens, these TPV/r regimens do not appear to be the best options for treatment-naïve patients based on their safety profiles.

Abstract IA46: Towards implementation of T-cell therapy in pancreatic cancer

In contrast to the general belief that pancreatic ductal adenocarcinoma is a poorly immunogenic tumor, we found cumulative evidence for an adaptive immune response in this aggressive cancer type. Immunohistochemistry reveals prominent T-cell infiltrates in the majority (~ 70%) of tumor biopsies, and these tumor-infiltrating lymphocytes (TILs) can be isolated and expanded ex vivo with similar efficiency as those isolated from melanoma. Furthermore, comparison of the T-cell receptor repertoire between TIL and PBMC isolates from patients points at the selective expansion of T-cell subsets in the tumors. Finally, in ~ 50% of tumor specimen, T-cell infiltration is accompanied by the presence of tertiary lymphoid structures that comprise areas rich in CD3+ T-cells and CD208+ dendritic cells as well as areas rich in B-cells and follicular dendritic cells.

Based on these findings, our current efforts aim at:

- Evaluating neoadjuvant treatment with agonist immunostimulatory antibodies as a means to mobilize this pre-existing immune response in patients with primary resectable disease*

- Analysis of the anti-tumor reactivity and antigen-specificity of TCR-species that are prominently enriched in the tumor as compared to PBMC.

- Exploration of TIL therapy for treatment of recurrent disease.

* Clinical trial in context of FP7 EU IACT program; Immunostimulatory Antibodies for Cancer Treatment

Citation Format: Rienk Offringa, Isabel Poschke, Michael Volkmar, Oliver Strobel, Frank Bergmann, Niels Halama, Dirk Jäger, Ugur Sahin, Markus Büchler. Towards implementation of T-cell therapy in pancreatic cancer. [abstract]. In: Proceedings of the CRI-CIMT-EATI-AACR Inaugural International Cancer Immunotherapy Conference: Translating Science into Survival; September 16-19, 2015; New York, NY. Philadelphia (PA): AACR; Cancer Immunol Res 2016;4(1 Suppl):Abstract nr IA46.

Cyst Features and Risk of Malignancy in Intraductal Papillary Mucinous Neoplasms of the Pancreas: Imaging and Pathology

Background

Intraductal papillary mucinous neoplasms (IPMNs) display diverse macroscopic, histological, and immunohistochemical characteristics with typical morphological appearance in magnetic resonance imaging. Depending on those, IPMNs may show progression into invasive carcinomas with variable frequency. Overall, IPMN-associated invasive carcinomas are found in about 30% of all IPMNs, revealing phenotpyes comparable with conventional ductal adenocarcinomas or mucinous (colloid) carcinomas of the pancreas. In Sendai-negative side-branch IPMNs, however, the annual risk of the development of invasive cancer is 2%; thus, risk stratification with regard to imaging and preoperative biomarkers and cytology is mandatory.

Methods and Results

The present study addresses the radiological and interventional preoperative measures including histological features to determine the risk of malignancy and the prognosis of IPMNs.

Conclusion

While preoperative imaging largely relies on the detection of macroscopic features of IPMNs, which are associated with a divergent risk of malignant behavior, in resected specimens the determination of the grade of dysplasia and the detection of an invasive component are the most important features to estimate the prognosis of IPMNs.

[Therapy of inherited diseases of platelet function. Interdisciplinary S2K guideline of the Permanent Paediatric Committee of the Society of Thrombosis and Haemostasis Research (GTH e. V.)]

Inherited disorders of platelet function are a heterogeneous group. For optimal prevention and management of bleeding, classification and diagnosis of the underlying defect are highly recommended. An interdisciplinary guideline for a diagnostic approach has been published (AWMF # 086-003 S2K; Hämostaseologie 2014; 34: 201-212). Underlying platelet disorder, platelet count, age and clinical situation modify treatment. Exclusive transfusion of platelet concentrates may be inappropriate as potentially adverse effects can outweigh its benefit. A stepwise and individually adjusted approach for restitution and maintenance of haemostasis is recommended. Administration of antifibrinolytics is generally endorsed, but is of particular use in Quebec disease. Restricted to older children, desmopressin is favourable in storage pool disease and unclassified platelet disorders. Although licensed only for patients with Glanzmann thrombasthenia and alloantibodies, in clinical practice rFVIIa is widely used in inherited platelet disorders with severe bleeding tendency. This guideline aims at presenting the best available advice for the management of patients with inherited platelet function disorders.

Abstract 1417: Clonal succession in pancreatic cancer progression is not driven by genetic instability

Our group has recently shown that human pancreatic cancer (PDAC) progression is driven by a succession of transiently active tumor initiating cell (TIC) clones during serial xenotransplantation. Genetic labeling demonstrated that serial PDAC xenograft tumors and even tumors of parallel mice transplanted with cells from the same donor xenografts harbored very little to no overlap of active TIC clones, indicating substantial changes in the proliferative activity of individual TIC predominantly producing progeny without detectable tumor-initiating activity. We now asked whether observed clonal activation and inactivation is caused by acquisition of de novo mutations during evolution of genetic subclones or by functional plasticity of genetically stable TIC clones. Therefore, we monitored somatic non-synonymous mutations in culture and during PDAC progression in genetically marked serial xenografts of two patients. DNA was isolated from xenografts, primary TIC cultures and corresponding normal pancreas or primary tumor tissue. Following paired-end exome sequencing, reads were aligned to a concatenated hs37d5 human and mm10 mouse genome assembly and human specific single nucleotide variants (SNVs) and small insertions/deletions (indels) were identified. We found a total of 45 altered gene coding genomic loci (P1 = 10; P2 = 35) not present in control tissue. Strikingly, most SNVs detected were present in all samples, only very few SNV were acquired during serial transplantation. In P1, 4 novel SNVs not present in the original patient tumor sample were detected within coding regions of TTC13, OR4K15, SSPO and TPGS1. Allele frequencies ranged from 2-27% in serial xenografts. In xenografts of P2 we detected 35 SNVs not present in healthy tissue. Of these, one mutation in the gene C10orf12 aroused after serial transplantation with a maximum altered allele frequency of 17%. None of these mutations is a known cancer driver or was found as recurrent in large scale cancer sequencing approaches. To evaluate whether the clonal TIC dynamics within established tumors are recapitulated in vitro, we analysed individual TIC clone kinetics in serially passaged cultures and in cultures derived from transduced xenografts. Strikingly, the kinetics in vitro were similar to those observed within serially transplanted xenografts. Every culture passage was formed by a distinct set of actively proliferating cell clones without significant overlap between individual serial passages indicating that clonal succession of TIC activity in PDAC is not dependent on the cellular context in tumors in vivo. The remarkable genetic stability of xenografts during serial transplantation strongly indicates that changes in the functional state of PDAC cells and not genetic instability drive clonal succession of TIC activity in PDAC.

Citation Format: Karl Roland Ehrenberg, Claudia R. Ball, Felix Oppel, Naveed Ishaque, Taronish D. Dubash, Sebastian M. Dieter, Christopher M. Hoffmann, Ulrich Abel, Moritz Koch, Jens Werner, Frank Bergmann, Manfred Schmidt, Christof von Kalle, Wilko Weichert, Jürgen Weitz, Benedikt Brors, Hanno Glimm. Clonal succession in pancreatic cancer progression is not driven by genetic instability. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1417. doi:10.1158/1538-7445.AM2015-1417

Primary melanoma of the prostate: case report and review of the literature

Background

Primary melanoma of the prostate has an extremely rare incidence. Only five cases have been reported in the literature and prognosis is poor. The most likely origin of prostatic melanoma is the transitional epithelium of the prostatic urethra. Surgical care for primary melanoma of mucosal sites is less well established than for primary cutaneous melanoma, but excision of the primary is recommended if the patient has no systemic disease.

Case presentation

Here, we describe a case of primary malignant melanoma of the prostate. A 37-year-old male patient with history of both chemo- and radiation therapy for Hodgkin’s disease was admitted to the University Hospital Heidelberg on suspicion of pleomorphic sarcoma of the bladder. In-house diagnostic work-up revealed a malignant melanoma of the prostate. We then performed radical prostatectomy with extended lymphadenectomy. Despite presumably curative surgery, the patient suffered from early relapse of disease with pulmonary metastasis. Systemic chemotherapy and subsequent immuno-oncologic treatment was thereafter initiated.

Conclusion

Since prostatic melanoma is a rare disease and a melanoma metastasis of unknown primary is the differential diagnosis, a multidisciplinary approach including early imaging to rule out possible metastases and to search for another potentially existing primary is advisable. To prevent complications related to local tumor progression and to receive tissue for mutational analysis, we recommend complete surgical resection to reduce the tumor mass. Novel immune and targeted oncologic therapies can lead to an improved survival in some cases and support of clinical trials is needed.