The scientific use of secondary data, especially of claims data from health insurance funds, has continuously increased in the last years. Therefore the Working Group "Collection and Use of Secondary Data" (AGENS) of the German Society of Social Medicine and Prevention (DGSMP) took the initiative to define quality standards for secondary data analysis. Starting with a review of the Good Epidemiologic Practice (GEP) AGENS adapted the GEP to the specific requirements of secondary data analysis by a multi-stage consensus process. The guideline Good Practice Secondary Date Analysis (GPS) was adopted on January 15 (th), 2005. GPS consists of 10 guidelines which are divided in explaining comments and recommendations. The GPS are targeted to set up standards for secondary data analysis, and they may also be used as a foundation of contracts between data owners and scientists. They are addressed to scientists from health services research and social medicine. AGENS commits itself to revise GPS continuously.

OBJECTIVE

gastroenteropancreatic (GEP) neuroendocrine tumors, suspected on clinical basis, are often difficult to localize. We report our experience with endoscopic ultrasonography (EUS) in the preoperative localization of pancreatic endocrine tumors (PETs), compared to other imaging modalities, and in staging and following up carcinoid tumors (CTs) of the gastrointestinal (GI) wall.

METHODS

50 patients (20 males; mean age 54 years), 39 with suspected PETs and 11 with GI CTs underwent EUS (Olympus GF-UM2 or GF-UM3). EUS data could be compared with resected specimens in 25 out of the 39 PETs and five out of the 11 CTs.

RESULTS

in the PETs group 42 tumors (35<20 mm) were removed: 23 in the pancreas, eight in the duodenum, and 11 in the lymph nodes. EUS correctly localized 20 out of the 23 (87%) pancreatic tumors, included 11 out of the 12 (91.6%) insulinomas, three out of the eight (37.5%) duodenal gastrinomas, and ten out of the 11 (90.9%) metastatic lymph nodes. Furthermore EUS accurately evaluated the depth of parietal invasion of CTs in three out of four patients (75%) (two after and one prior to endoscopic resection). In three patients EUS was confirmed as normal on resected specimens (two pancreas and one stomach). In the PETs group, a correct localization was obtained by ultrasonography (US) only in 17.4% of cases, by computed tomography (CT) in 30.4%, by magnetic resonance imaging (MRI) in 25%, by angiography in 26.6%, and by somatostatin receptor scintigraphy in 15.4%.

CONCLUSIONS

EUS must be considered the first-intention method in localizing PETs and is helpful in decision making and management of GEP endocrine tumors.

BACKGROUND

Transcriptome analysis by microarrays has produced important advances in biomedicine. For instance in multiple myeloma (MM), microarray approaches led to the development of an effective disease subtyping via cluster assignment, and a 70 gene risk score. Both enabled an improved molecular understanding of MM, and have provided prognostic information for the purposes of clinical management. Many researchers are now transitioning to Next Generation Sequencing (NGS) approaches and RNA-seq in particular, due to its discovery-based nature, improved sensitivity, and dynamic range. Additionally, RNA-seq allows for the analysis of gene isoforms, splice variants, and novel gene fusions. Given the voluminous amounts of historical microarray data, there is now a need to associate and integrate microarray and RNA-seq data via advanced bioinformatic approaches.

METHODS

Custom software was developed following a model-view-controller (MVC) approach to integrate Affymetrix probe set-IDs, and gene annotation information from a variety of sources. The tool/approach employs an assortment of strategies to integrate, cross reference, and associate microarray and RNA-seq datasets.

RESULTS

Output from a variety of transcriptome reconstruction and quantitation tools (e.g., Cufflinks) can be directly integrated, and/or associated with Affymetrix probe set data, as well as necessary gene identifiers and/or symbols from a diversity of sources. Strategies are employed to maximize the annotation and cross referencing process. Custom gene sets (e.g., MM 70 risk score (GEP-70)) can be specified, and the tool can be directly assimilated into an RNA-seq pipeline.

CONCLUSIONS

A novel bioinformatic approach to aid in the facilitation of both annotation and association of historic microarray data, in conjunction with richer RNA-seq data, is now assisting with the study of MM cancer biology.

Mantle cell lymphoma (MCL) is an aggressive neoplasm with a short survival. Cases with leukaemic MCL and splenomegaly without adenopathies (non-nodal MCL) may have a more indolent course. To gain insights into the biological features underlying this presentation, we investigated the gene expression profile (GEP) and the IGHV mutational status in a cohort of leukaemic MCL cases. Comparison of MCL with other lymphoproliferative disorders (i.e. splenic marginal zone lymphoma, follicular lymphoma, chronic lymphocytic leukaemia) revealed a MCL signature enriched for the following gene categories: mitochondrion, oxidoreductase activity, response to stress, to DNA damage and TP53-pathway. Furthermore, GEP analysis revealed that non-nodal MCL cases were characterized by the down-modulation of the following gene categories: cell projection, actin cytoskeleton organization, cell adhesion (ITGAE, CELSR1, PCDH9) and tumour invasion/progression (PGF, ST14, ETS1, OCIAD1, EZR). Many down-modulated genes were related to the TP53-pathway and to DNA damage response. IGHV status proved unmutated in all nodal and mutated in all non-nodal MCL. Non-nodal leukaemic MCLs display a peculiar clinical presentation, with distinctive biological features, such as mutated IGHV and a transcriptional profile lacking tumour invasion properties, that might contribute to the absence of nodal involvement and to the less aggressive clinical course.

OBJECTIVE

Gain-of-function mutations of enhancer of Zeste homolog 2 (EZH2) occur frequently in diffuse large B-cell lymphomas and in follicular lymphomas. However, the frequency of EZH2 mutation in Chinese follicular lymphomas and the potential targets affected by this mutation are unknown.

METHODS

We determined EZH2 codon 641 mutations in Chinese follicular lymphomas (n = 124) and compared them with Western follicular lymphomas (n = 70) using a sensitive pyrosequencing assay. Gene expression profiling (GEP) was performed to determine differential gene expression between the mutated versus unmutated subgroups, and selected genes were validated using immunohistochemistry.

RESULTS

Our results showed similar frequencies of EZH2 codon 641 mutations in Chinese and Western follicular lymphoma cohorts (16.9% vs. 18.6%, χ(2) test, P = 0.773), including all five reported mutation variants. We observed significant association of EZH2 mutation with low morphologic grade follicular lymphomas (grade 1-2, 23.6% vs. grade 3, 7.7%, χ(2) test, P = 0.02). EZH2 mutations also showed significant association with BCL2 rearrangement in the Chinese cohort (26.8% vs. 8.8%, χ(2) test, P = 0.008) and combined cohorts (26.3% vs. 9.1%, χ(2) test, P = 0.002). GEP analysis identified several genes, including TCF4, FOXP1, TCL1A, BIK, and RASSF6P, with significantly lower mRNA expression (P < 0.01) in mutated cases, and the potential target TCL1A showed consistent results at the protein level.

CONCLUSIONS

Similar prevalence of EZH2 mutation in two ethnic groups suggests shared pathogenetic mechanisms. The much lower frequency of EZH2 mutation in cases without BCL2 translocation suggests a different pattern of evolution of this subtype of follicular lymphoma. GEP studies showed a set of differentially expressed genes and suggested that EZH2 mutation may help to lock the tumor cells at the germinal center stage of differentiation.

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) are potentially malignant with variable biologic behavior that originates from neuroendocrine cells of digestive tract. Recently, the existence of cancer stem cells (CSC) was demonstrated in tumors of gastrointestinal tract. CD133 is a transmembrane glycoprotein that serves as a CSC marker in various malignancies. However, the expression of CD133 in neuroendocrine neoplasms (NEN) of digestive tract has not been studied. We evaluated tissue expression of CD133 by immunohistochemistry in 90 NENs of digestive tract with their matched non-neoplastic mucosa including stomach (n=15), small intestine (n=7), appendix (n=3), colon (n=8), rectum (n=41), pancreas (n=2), gallbladder (n=4) and liver (n=10). Tumors were divided according to 2010 WHO classification. CD133 was expressed in 30.3% (17/56) of well-differentiated neuroendocrine tumors (NET), 26.1% (6/23) of poorly-differentiated neuroendocrine carcinomas (NEC) and 63.6% (7/11) of mixed adenoneuroendocrine carcinoma (MANECs). MANEC refers to existence of both adenocarcinoma and NEC together, each one comprising at least 30% of the tumor. CD133 was expressed in cytoplasm, luminal-side of cell membrane, or both and the staining pattern correlated with tumor growth pattern. CD133 expression was not significantly correlated with tumor grade, site, expression of neuroendocrine markers (chromogranin-A and synaptophysin) and patients' survival. Thus, CD133 expression may lack prognostic significance in GEP-NETs. Importantly, CD133 was not detectable in non-neoplastic neuroendocrine cells of digestive system including pancreatic islets. In conclusion, CD133 is expressed in poorly-differentiated NECs and well-differentiated NETs of the digestive tract.

OBJECTIVE

To evaluate the use of 99mTc-EDDA-hydrazinonicotinyl-Tyr3-octreotide (Tc-TOC) for staging and follow-up of neuroendocrine gastro-entero-pancreatic (GEP) tumors with special focus on the acquisition protocol including single photon emission computed tomography (SPECT).

METHODS

Eighty-eight patients (37 female, 51 male; age range: 16 to 81 years; mean age: 56.3 years) were studied: 42 patients for staging after initial histological confirmation and 46 patients during post-therapy follow-up. An average activity of 400 MBq of the radiopharmaceutical was injected. All tumors originated from neuroendocrine tissue of the gastroenteropancreatic tract. Whole body scintigrams at 4 h postinjection and SPECT of the abdomen were obtained in all patients. Additional planar images of the abdomen were acquired at 2 h after injection in 68 patients.

RESULTS

The Tc-TOC scan result was true-positive in 56 patients, true-negative in 17, false-negative in 14, and false-positive in 1 patient. The false-positive finding was caused by a colonic adenoma. Overall, a scan sensitivity of 80% (56/70 patients), specificity of 94.4% (17/18 patients) and accuracy of 82.9% (73/88 patients) were calculated on patient basis. In total, Tc-TOC detected 357 foci in 69 patients. In 7 patients equivocal findings were observed in the bowel at 4 h postinjection without corresponding tracer uptake in the scan 2 h earlier, meaning that these abnormal findings were correctly classified as non-malignant. In addition to planar views, SPECT revealed further 62 lesions.

CONCLUSIONS

Tc-TOC with one-day, dual-time acquisition protocol is an accurate staging procedure in patients with neuroendocrine GEP tumors. SPECT shows high sensitivity for detection of abdominal lesions, while earlier images improve the reliability of abnormal abdominal findings.

EFA6A is a guanine nucleotide exchange protein (GEP) that can specifically activate ADP-ribosylation factor 6 (ARF6) in vitro. A recent study has demonstrated that ARF6 is involved in the dendritic formation of developing hippocampal neurons [Hernandez-Deviez et al. (2002) Nature Neurosci., 5, 623-624]. This study examined a potential role for EFA6A in hippocampal development in Wistar rats. Our results provided definitive evidence for somatodendritic localization of EFA6A mRNA in both cultured and in vivo hippocampal neurons by nonradioactive in situ hybridization. During postnatal development, EFA6A mRNA was dramatically increased and its dendritic localization was most evident between P7 and P14. In contrast, ARF6 mRNA was confined to the neuronal layers of the hippocampus throughout development. In addition, the overexpression of a GEP-defective mutant of EFA6A enhanced the dendritic formation of the primary hippocampal neurons. The present findings suggest that EFA6A is intimately involved in the regulation of the dendritic development of hippocampal neurons.

Despite high cure rates 25% of children with acute lymphoblastic leukaemia (ALL) relapse and have dismal outcome. Crucially, many are currently stratified as standard risk (SR) and additional markers to improve patient stratification are required. Here we have used diagnostic bone marrow specimens from 101 children with pre-B ALL to examine the use of gene expression profiles (GEP) as predictors of long-term clinical outcome. Patients were divided into two cohorts for model development and validation based on availability of specimen material. Initially, GEP from 55 patients with sufficient material were analysed using HG-U133A microarrays, identifying an 18-gene classifier (GC) that was more predictive of outcome than conventional prognostic parameters. After feature selection and validation of expression levels by quantitative reverse transcription polymerase chain reaction (qRT-PCR), a three-gene qRT-PCR risk index [glutamine synthetase (GLUL), ornithine decarboxylase antizyme inhibitor (AZIN), immunoglobulin J chain (IGJ)] was developed that predicted outcome with an accuracy of 89% in the array cohort and 87% in the independent validation cohort. The data demonstrate the feasibility of using GEP to improve risk stratification in childhood ALL. This is particularly important for the identification of patients destined to relapse despite their current stratification as SR, as more intensive front-line treatment options for these individuals are already available.

Pediatric mixed-lineage leukemia (MLL)-rearranged acute monoblastic leukemia with t(9;11)(p22;q23) has a favorable outcome compared with other MLL-rearranged AML. The biologic background for this difference remains unknown. Therefore, we compared gene expression profiles (GEPs; Affymetrix HGU133 + 2.0) of 26 t(9;11)(p22;q23) patients with 42 other MLL-rearranged AML patients to identify differentially expressed genes. IGSF4, a cell-cell adhesion molecule, was found to be highly expressed in t(9;11)(p22;q23) patients, which was confirmed by real-time quantitative polymerase chain reaction and Western blot. IGSF4 expression within t(9;11)(p22;q23) patients was 4.9 times greater in French-American-British morphology classification (FAB)-M5 versus other FAB-types (P = .001). Methylation status investigation showed that high IGSF4-expressing t(9;11)(p22;q23) patients with FAB-M5 have no promoter hypermethylation, whereas all other cases do. Cell-line incubation with demethylating agent decitabine resulted in promoter demethylation and increased expression of IGSF4. Down-regulation of IGSF4 by siRNA did not affect proliferation or drug sensitivity. In a cohort of 79 MLL-rearranged AML cases, we show significant better overall survival for cases with high IGSF4 expression (5-year overall survival 0.70 vs 0.37, P = .03) In conclusion, we identified IGSF4 overexpression to be discriminative for t(9;11)(p22;q23) patients with FAB-M5, regulated partially by promoter methylation and resulting in survival benefit.

OBJECTIVE

CKS1B is significantly upregulated in multiple myeloma and associated with poor prognosis. The identification of novel therapies is essential for effective treatment of patients resistant to chemotherapy. The NEDD8 inhibitor MLN4924 selectively targets SCF(Skp2) activation and offers a more specific approach to protein degradation inhibition than total proteasomal inhibition. The goal of this study was to evaluate whether MLN4924 is effective in high CKS1B conditions and identify mechanisms regulating drug potency.

METHODS

Bortezomib and MLN4924 sensitivity was assessed through proliferation, viability, clonogenic potential, and senescence induction in cells overexpressing CKS1B. The mechanism for MLN4924 sensitivity was elucidated by immunoblot analysis of SCF(skp) substrates and confirmed by shRNA knockdown. The clinical relevance of the NEDD8 pathway was examined in gene expression profiles (GEP) derived from healthy people, patients with monoclonal gammopathy of undetermined significance (MGUS), and multiple myeloma.

RESULTS

Cells overexpressing CKS1B were resistant to bortezomib but sensitive to MLN4924. Treatment of CKS1B-overexpressing cells with MLN4924 decreased proliferation, clonogenicity, and induced senescence. MLN4924, but not bortezomib, induced stabilization of p21 and knockdown of p21 resulted in loss of MLN4924 sensitivity. Patients with MGUS and multiple myeloma exhibited increased expression of NEDD8 pathway genes relative to normal plasma cells. Multiple myeloma patients with high NEDD8 expression were linked to bortezomib resistance in clinical trials, and had inferior outcomes.

CONCLUSIONS

Our data demonstrate that cells with elevated CKS1B expression are resistant to bortezomib but sensitive to MLN4924 and offer a mechanism through the stabilization of p21. These findings provide rationale for targeting the NEDD8 pathway in multiple myeloma patients exhibiting elevated expression of CKS1B. Clin Cancer Res; 21(24); 5532-42. ©2015 AACR.

Few studies were conducted investigating the immunological profiles in gastrointestinal stromal tumors (GIST). Adaptive and innate immune cells are present in the tumor microenvironment, indicating GIST as inflamed tumors. In addition, murine models suggested a potential interaction between immune components and imatinib. In this retrospective study, the GIST immunological profile was investigated through in silico analysis and immunohistochemistry (IHC), exploring the basis for immunotherapy approaches. Gene expression profiles (GEP) from 31 KIT/PDGFRA-mutant GIST were analyzed to evaluate the tumor microenvironment and immunotherapy predictive signatures such as the expanded IFN-γ-induced immune signature (EIIS) and the T-cell-inflamed signature (TIS). GEP and IHC supported the presence of immune infiltrate in GIST, with dominance of CD4+ and CD8+ T cells and M2 macrophages showing a remarkable similarity with melanoma microenvironment. The EIIS genes were expressed in most of GIST samples and positively correlated with PD-L1 abundance (p < .0001). Co-expression was also found between PD-L1 and CD8A (p < .0001) or CD8B (p = .0003). Moreover, the median TIS score for GIST was between the 65th and 70th percentile of the Cancer Genome Atlas dataset, in the same range of tumors responding to anti-PD-1/PD-L1. Analysis of the Gene Expression Omnibus database GIST samples pre- and post-treatment confirmed that imatinib downregulates PD-L1 and IRF1 expression through the inhibition of KIT and PDGFRA, thus contributing to counteract the suppressed adaptive immune response against GIST. The presence of a rich immune infiltrate in GIST along with the presence of TIS and EIIS suggests that GIST may benefit from immunotherapy along with tyrosine kinase inhibitors.

OBJECTIVE

To examine the effect of intratumor heterogeneity (ITH) on detection of genes within gene expression panels (GEPs) and the subsequent ability to predict prognostic risk.

METHODS

Multiplexed barcoded RNA analysis was used to measure the expression of 141 genes from five GEPs (Oncotype Dx, MammaPrint, PAM50, EndoPredict, and Breast Cancer Index) in breast cancer tissue sections and tumor-rich cores from 71 estrogen receptor (ER)-positive node-negative tumors, on which clinical Oncotype Dx testing was previously performed. If the tumor had foci of high Ki67 (n = 26), low/negative progesterone receptor (PR; n = 13), or both (n = 5), additional cores were obtained. In total, 181 samples were processed. Oncotype Dx recurrence scores were calculated from NanoString nCounter gene expression data.

RESULTS

Hierarchical clustering using all GEP genes showed that majority (61 of 71) of tumor samples clustered by patient, indicating greater interpatient heterogeneity (IPH) than ITH. We found a strikingly high correlation between Oncotype Dx recurrence scores obtained from whole sections versus tumor-rich cores (r = 0.94). However, high Ki67 and low PR cores had slightly higher but not statistically significant recurrence scores. For 18 of 71 (25%) patients, scores were divergent between sections and cores and crossed the boundaries for low, intermediate, and high risk.

CONCLUSIONS

Our study indicates that in patients with highly heterogeneous tumors, GEP recurrence scores from a single core could under- or overestimate prognostic risk. Hence, it may be a useful strategy to assess multiple samples (both representative and atypical cores) to fully account for the ITH-driven variation in risk prediction. Clin Cancer Res; 22(21); 5362-9. ©2016 AACR.

BACKGROUND

The lack of uniform criteria for coding of gastroenteropancreatic neuroendocrine neoplasia (GEP-NEN) has hampered previous epidemiological studies. The epidemiology of GEP-NEN was investigated in this study using currently available criteria.

METHODS

All patients diagnosed with GEP-NEN between January 2003 and December 2013 in a well defined Norwegian population of approximately 350 000 people were included. Age- and sex-adjusted incidence rates were calculated. The current 2010 World Health Organization criteria, European Neuroendocrine Tumour Society classification and International Union Against Cancer (UICC) classification were used.

RESULTS

A total of 204 patients (114 male, 55.9 per cent) were identified. The median age at diagnosis was 61 (range 10-94) years. The annual overall crude incidence was 5.83 per 100,000 inhabitants, with an increasing trend (P = 0.033). The most frequent location was small intestine (60 patients, 29.4 per cent) followed by appendix (48 patients, 23.5 per cent) and pancreas (33 patients, 16.2 per cent). Grade 1 tumours were more common in gastrointestinal (100 patients, 58.5 per cent) than in pancreatic (9 patients, 27 per cent) NEN. According to the UICC classification, 77 patients (37.7 per cent) had stage I, 17 patients (8.3 per cent) stage II, 37 patients (18.1 per cent) stage III and 70 patients (34.3 per cent) had stage IV disease. No patient with stage I disease had grade 3 tumours; advanced tumour grade increased with stage.

CONCLUSIONS

A high crude incidence of GEP-NEN, at 5.83 per 100,000 inhabitants, was noted together with a significant increasing trend over time.

The effects of i.p. administration of the gamma-aminobutyric acid (GABA) uptake inhibitors R(-)N-(4,4-di(3-methylthien-2-yl)-but-3-enyl) nipecotic acid hydrochloride (tiagabine; molecular weight 412.0), (1-(2-(((diphenylmethylene)-amino)oxy)ethyl)-1,2,5,6-tetrahydro-3- pyridinecarboxylic acid hydrochloride (NNC-711; molecular weight 386.9), and (+/-)-nipecotic acid (molecular weight 128.2) are compared with those of carbamazepine (molecular weight 236.3) on sound-induced seizures and locomotor performance in genetically epilepsy-prone (GEP) rats. The ED50 value against clonic seizures (in mumol kg-1 at the time of maximal anticonvulsant effect) for tiagabine was 23 (0.5 h), and for NNC-711 was 72 (1 h), and for carbamazepine was 98 (2 h). (+/-)-Nipecotic acid (0.4-15.6 mmol kg-1) was not anticonvulsant. High doses of NNC-711 (207-310 mumol kg-1) and of (+/-)-nipecotic acid (39-78 mmol kg-1) induced ataxia and myoclonic seizures 0.25-1 h. Tiagabine and carbamazepine did not induce myoclonic seizures and had similar therapeutic indices (locomotor deficit ED50/anticonvulsant ED50) ranging from 0.4 to 1.9. In Papio papio, we observed a reduction in photically induced myoclonic seizures with tiagabine (2.4 mumol kg-1 i.v.) accompanied with neurological impairment. Tiagabine has comparable anticonvulsant action to carbamazepine in rats and has anticonvulsant effects in non-human primates supporting the potential use of inhibitors of GABA uptake as therapy for epilepsy.

We reviewed bone marrow studies from 351 multiple myeloma (MM) cases, selecting 12 cases (3.4%) with predominantly small lymphocyte-like morphologic features resembling B-cell lymphoma, and correlated their genetic and clinical features. All exhibited a diffuse interstitial pattern of marrow involvement. Small lymphocyte-like plasma cells were all CD45- with bright CD38 and CD138 expression and CD20 expression in 5 cases. No case had an increase in bone marrow B lymphocytes by flow cytometry. Of 12 cases, 9 were classified as the CD-2 molecular class by gene expression profiling (GEP). The 29 CD-2 class cases with (n = 9) and without (n = 20) small lymphocyte-like features could not be discerned from one another using global GEP. Event-free, but not overall, survival was significantly better in cases with small lymphocyte-like features among those sharing the CD-2 subtype. Small lymphocyte-like MM is a rare, morphologically challenging variant distinguished from B-cell lymphoma by lack of CD45 and presence of CD138 and the clinical presentation of MM. Most cases share a common GEP signature dominated by hyperexpression of cyclin D1 or cyclin D3 genes, with increased expression of the B-cell genes CD20 and VPREB3.

Genomic information is increasingly being used to personalize health care. One example is gene expression profiling (gep) tests, which estimate recurrence risk to inform chemotherapy decisions in breast cancer. Recently, gep tests were publicly funded in Ontario. We explored the perceived utility of gep tests, focusing on the factors influencing their use and value in treatment decision-making by patients and oncologists.

METHODS

We conducted interviews with oncologists (n = 14) and interviews and a focus group with early-stage breast cancer patients (n = 28) who underwent gep testing. Both groups were recruited through oncology clinics in Ontario. Data were analyzed using the content analysis and constant comparison techniques.

RESULTS

Narratives from patients and oncologists provided insights into various factors facilitating and restricting access to gep. First, oncologists are positioned as gatekeepers of gep, providing access in medically appropriate cases. However, varying perceptions of appropriateness led to perceived inequities in access and negative impacts on the doctor-patient relationship. Second, media attention facilitated patient awareness of gep, but also complicated gatekeeping. Third, the dedicated administration attached to gep was burdensome and led to long waits for results and also to increased patient anxiety and delayed treatment. Collectively, because of barriers to access, those factors inadvertently heightened the perceived value of gep for patients relative to other prognostic indicators.

CONCLUSIONS

Our study delineates the factors facilitating and restricting access to gep, and highlights the roles of media and organization of services in the perceived value and utilization of gep. The results identify a need for administrative changes and practice guidelines to support streamlined and standardized use of gep tests.

A non-invasive gene-expression profiling (GEP) test for rejection surveillance of heart transplant recipients originated in the USA. A European-based study, Cardiac Allograft Rejection Gene Expression Observational II Study (CARGO II), was conducted to further clinically validate the GEP test performance.

Blood samples for GEP testing (AlloMap(®), CareDx, Brisbane, CA, USA) were collected during post-transplant surveillance. The reference standard for rejection status was based on histopathology grading of tissue from endomyocardial biopsy. The area under the receiver operating characteristic curve (AUC-ROC), negative (NPVs), and positive predictive values (PPVs) for the GEP scores (range 0-39) were computed. Considering the GEP score of 34 as a cut-off (>6 months post-transplantation), 95.5% (381/399) of GEP tests were true negatives, 4.5% (18/399) were false negatives, 10.2% (6/59) were true positives, and 89.8% (53/59) were false positives. Based on 938 paired biopsies, the GEP test score AUC-ROC for distinguishing ≥3A rejection was 0.70 and 0.69 for ≥2-6 and >6 months post-transplantation, respectively. Depending on the chosen threshold score, the NPV and PPV range from 98.1 to 100% and 2.0 to 4.7%, respectively.

For ≥2-6 and >6 months post-transplantation, CARGO II GEP score performance (AUC-ROC = 0.70 and 0.69) is similar to the CARGO study results (AUC-ROC = 0.71 and 0.67). The low prevalence of ACR contributes to the high NPV and limited PPV of GEP testing. The choice of threshold score for practical use of GEP testing should consider overall clinical assessment of the patient's baseline risk for rejection.

Preliminary observations have indicated the existence of characteristic spectra of gastroenteropancreatic (GEP) neurohormonal peptides in endocrine tumors arising in foregut, midgut, and hindgut derivatives. In order to further explore this feature of GEP endocrine neoplasms, islet cell tumors from 14 patients were studied, as were endocrine tumors of the stomach, duodenum, and upper jejunum from 6, 5, and 2 patients, respectively. All tumors were examined immunohistochemically with antisera raised against islet hormones [insulin, somatostatin, glucagon, pancreatic polypeptide (PP)], peptides of the gastrin family [gastrin, cholecystokinin (CCK)], peptides of the secretin family [secretin, vasoactive intestinal peptide (VIP)], and substance P, neurotensin, leu-enkephalin, beta-endorphin, motilin, calcitonin, and ACTH. In addition, an ultrastructural investigation was made. Whenever possible, the immunohistochemical observations were correlated with the clinical manifestations and with the results of radioimmunochemical determination of GEP neurohormones in the blood. The pattern of immunoreactive neurohormonal peptides and the clinical picture were those to be expected in endocrine tumors arising in foregut derivatives. Some principles are proposed for the classification of GEP endocrine tumors on the basis of their histopathologic growth pattern, their spectrum of neurohormonal peptides, and their clinical manifestations.

Neuron-specific enolase (NSE) was studied by immunohistochemistry and radioimmunoassay in ten gastroenteropancreatic (GEP) neuroendocrine tumors. Tissue and serum levels of NSE from the same patients were also analyzed. In all cases, NSE was localized by immunohistochemistry as diffuse cytoplasmic staining to neuroendocrine cells. Tissue levels of NSE were elevated in eight of ten cases while the serum level of NSE was elevated only in one patient with a metastatic gastrinoma to the liver. Examination of the distribution of NSE in a wide range of tumors (n = 55) showed that it is relatively specific for neurons and neuroendocrine tumors. Eight of ten tumors analyzed immunohistochemically for nine polypeptide hormones contained more than one hormone. Two of ten tumors with only one hormone were positive for NSE. The clinical syndrome in all cases was related to only one hormone. These results indicate that the immunohistochemical demonstration of NSE is a good general marker for the neuroendocrine system. While tissue levels of NSE in GEP neuroendocrine tumors are generally elevated, the serum levels of NSE may only be markedly elevated with extensive metastatic disease.

Mantle cell lymphoma (MCL) is an aggressive type of B-cell non-Hodgkin lymphoma (NHL) associated with poor prognosis. Animal models of MCL are scarce. We established and characterized various in vivo models of metastatic human MCL by tail vein injection of either primary cells isolated from patients with MCL or established MCL cell lines (Jeko-1, Mino, Rec-1, Hbl-2, and Granta-519) into immunodeficient NOD.Cg-Prkdc(scid) Il2rg(tm1Wjl)/SzJ mice. MCL infiltration was assessed with immunohistochemistry (tissues) and flow cytometry (peripheral blood). Engraftment of primary MCL cells was observed in 7 out of 12 patient samples. The pattern of engraftment of primary MCL cells varied from isolated involvement of the spleen to multiorgan infiltration. On the other hand, tumor engraftment was achieved in all five MCL cell lines used and lymphoma involvement of murine bone marrow, spleen, liver, and brain was observed. Overall survival of xenografted mice ranged from 22 ± 1 to 54 ± 3 days depending on the cell line used. Subsequently, we compared the gene expression profile (GEP) and phenotype of the engrafted MCL cells compared with the original in vitro growing cell lines (controls). We demonstrated that engrafted MCL cells displayed complex changes of GEP, protein expression, and sensitivity to cytotoxic agents when compared with controls. We further demonstrated that our MCL mouse models could be used to test the therapeutic activity of systemic chemotherapy, monoclonal antibodies, or angiogenesis inhibitors. The characterization of MCL murine models is likely to aid in improving our knowledge in the disease biology and to assist scientists in the preclinical and clinical development of novel agents in relapsed/refractory MCL patients.

Gastroenteropancreatic neuroendocrine tumors (GEP-NETs) show limited sensitivity to cytotoxic agents, requiring the search for novel therapies. Recently, data from a phase III trial demonstrated that sunitinib produces a clinically significant improvement in progression-free survival in patients with unresectable, advanced, or metastatic GEP-NETs. Based on this finding, sunitinib became the first targeted drug approved for the treatment of GEP-NETs, paving the way for the approval of other anticancer agents in this drug-orphan disease. To date, results of trials involving other multitargeted tyrosine kinase inhibitors, such as sorafenib, the monoclonal antibody bevacizumab, and insulin-like growth factor 1 receptor inhibitors, have also shown promising results, and some are already being studied in phase III trials. This review updates the results of ongoing trials using inhibitors of growth factors and tyrosine kinase receptors involved in the carcinogenesis of GEP-NETs.

Gastroenteropancreatic neuroendocrine neoplasms (GEP-NENs) constitute a heterogeneous group of tumours associated with variable clinical presentations, growth rates, and prognoses. To improve the management of GEP-NENs, the WHO developed a classification system that enables tumours to be graded based on markers of cell proliferation in biopsy specimens. Indeed, histopathology has been a mainstay in the diagnosis of GEP-NENs, and the WHO grading system facilitates therapeutic decision-making; however, considerable intratumoural heterogeneity, predominantly comprising regional variations in proliferation rates, complicates the evaluation of tumour biology. The use of molecular imaging modalities to delineate the most-aggressive cell populations is becoming more widespread. In addition, molecular profiling is increasingly undertaken in the clinical setting, and genomic studies have revealed a number of chromosomal alterations in GEP-NENs, although the 'drivers' of neoplastic development have not been identified. Thus, our molecular understanding of GEP-NENs remains insufficient to inform on patient prognosis or selection for treatments, and the WHO classification continues to form the basis for management of this disease. Nevertheless, our increasing understanding of the molecular genetics and biology of GEP-NENs has begun to expose flaws in the WHO classification. We describe the current understanding of the molecular characteristics of GEP-NENs, and discuss how advances in molecular profiling measurements, including assays of circulating mRNAs, are likely to influence the management of these tumours.

BACKGROUND

A substantial number of patients who relapse and die from cutaneous melanoma (CM) are categorized as being at low risk by traditional staging factors. The 31-gene expression profile (31-GEP) test independently stratifies metastatic risk of patients with CM as low (Class 1, with 1A indicating lowest risk) or high (Class 2,with 2B indicating highest risk).

OBJECTIVE

To assess risk prediction by the 31-GEP test within 3 low-risk (according to the American Joint Committee on Cancer) populations of patients with CM: those who are sentinel lymph node (SLN) negative, those with stage I to IIA tumors, and those with thin (≤1 mm [T1]) tumors.

METHODS

A total of 3 previous validation studies provided a nonoverlapping cohort of 690 patients with 31-GEP results, staging information, and survival outcomes. Kaplan-Meier and Cox regression analysis were performed.

RESULTS

The results included the identification of 70% of SLN-negative patients who experienced metastasis as Class 2, the discovery of reduced recurrence-free survival for patients with thin tumors and Class 2B biology compared with that of those with Class 1A biology (P < .0001); and determination of the 31-GEP test as an independent predictor of risk compared with traditional staging factors in patients with stage I to IIA tumors.

CONCLUSIONS

Diagnoses spanned multiple versions of pathologic staging criteria.

CONCLUSIONS

The 31-GEP test identifies high-risk patients who are likely to experience recurrence or die of melanoma within low-risk groups of subpopulations of patients with CM who have SLN-negative disease, stage I to IIA tumors, and thin tumors.