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Molecular testing of cytological lung cancer specimens includes, beyond epidermal growth factor receptor (EGFR), emerging predictive/prognostic genomic biomarkers such as Kirsten rat sarcoma viral oncogene homolog (KRAS), neuroblastoma RAS viral [v-ras] oncogene homolog (NRAS), B-Raf proto-oncogene, serine/threonine kinase (BRAF), and phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA). Next-generation sequencing (NGS) and other multigene mutational assays are suitable for cytological specimens, including smears. However, the current literature reflects single-institution studies rather than multicenter experiences.Quantitative cytological molecular reference slides were produced with cell lines designed to harbor concurrent mutations in the EGFR, KRAS, NRAS, BRAF, and PIK3CA genes at various allelic ratios, including low allele frequencies (AFs; 1%). This interlaboratory ring trial study included 14 institutions across the world that performed multigene mutational assays, from tissue extraction to data analysis, on these reference slides, with each laboratory using its own mutation analysis platform and methodology.All laboratories using NGS (n = 11) successfully detected the study's set of mutations with minimal variations in the means and standard errors of variant fractions at dilution points of 10% (P = .171) and 5% (P = .063) despite the use of different sequencing platforms (Illumina, Ion Torrent/Proton, and Roche). However, when mutations at a low AF of 1% were analyzed, the concordance of the NGS results was low, and this reflected the use of different thresholds for variant calling among the institutions. In contrast, laboratories using matrix-assisted laser desorption/ionization-time of flight (n = 2) showed lower concordance in terms of mutation detection and mutant AF quantification.Quantitative molecular reference slides are a useful tool for monitoring the performance of different multigene mutational assays, and this could lead to better standardization of molecular cytopathology procedures. Cancer Cytopathol 2017;125:615-26. © 2017 American Cancer Society.

Purpose We investigated the global gene expression in a large panel of pancreatic endocrine tumors (PETs) aimed at identifying new potential targets for therapy and biomarkers to predict patient outcome. Patients and Methods Using a custom microarray, we analyzed 72 primary PETs, seven matched metastases, and 10 normal pancreatic samples. Relevant differentially expressed genes were validated by either quantitative real-time polymerase chain reaction or immunohistochemistry on tissue microarrays. Results Our data showed that: tuberous sclerosis 2 (TSC2) and phosphatase and tensin homolog (PTEN) were downregulated in most of the primary tumors, and their low expression was significantly associated with shorter disease-free and overall survival; somatostatin receptor 2 (SSTR2) was absent or very low in insulinomas compared with nonfunctioning tumors; and expression of fibroblast growth factor 13 (FGF13) gene was significantly associated with the occurrence of liver metastasis and shorter disease-free survival. TSC2 and PTEN are two key inhibitors of the Akt/mammalian target of rapamycin (mTOR) pathway and the specific inhibition of mTOR with rapamycin or RAD001 inhibited cell proliferation of PET cell lines. Conclusion Our results strongly support a role for PI3K/Akt/mTOR pathway in PET, which ties in with the fact that mTOR inhibitors have reached phase III trials in neuroendocrine tumors. The finding of differential SSTR expression raises the potential for SSTR expression to be evaluated as a marker of response to somatostatin analogs. Finally, we identified FGF13 as a new prognostic marker that predicted poorer outcome in patients who were clinically considered free from disease.

PurposeWe investigated the global microRNA expression patterns in normal pancreas, pancreatic endocrine tumors and acinar carcinomas to evaluate their involvement in transformation and malignant progression of these tumor types. MicroRNAs are small noncoding RNAs that regulate gene expression by targeting specific mRNAs for degradation or translation inhibition. Recent evidence indicates that microRNAs can contribute to tumor development and progression and may have diagnostic and prognostic value in several human malignancies.Materials and MethodsUsing a custom microarray, we studied the global microRNA expression in 12 nontumor pancreas and 44 pancreatic primary tumors, including 12 insulinomas, 28 nonfunctioning endocrine tumors, and four acinar carcinomas.ResultsOur data showed that a common pattern of microRNA expression distinguishes any tumor type from normal pancreas, suggesting that this set of microRNAs might be involved in pancreatic tumorigenesis; the expression of miR-103 and miR-107, associated with lack of expression of miR-155, discriminates tumors from normal; a set of 10 microRNAs distinguishes endocrine from acinar tumors and is possibly associated with either normal endocrine differentiation or endocrine tumorigenesis; miR-204 is primarily expressed in insulinomas and correlates with immunohistochemical expression of insulin; and the overexpression of miR-21 is strongly associated with both a high Ki67 proliferation index and presence of liver metastasis.ConclusionThese results suggest that alteration in microRNA expression is related to endocrine and acinar neoplastic transformation and progression of malignancy, and might prove useful in distinguishing tumors with different clinical behavior.

To determine the genetic differences/similarities in ampulla of Vater cancers (AVC) with respect to other pancreatic tumor types. We analyzed eight cases of primary AVC by genome-wide allelotyping on DNA obtained from frozen tissue. A total of 372 microsatellite loci were used for each case, for a total of 2,976 microsatellites analyzed. Of the 2,159 informative markers, 400 were allelic losses and 1,759 markers were retained for an average fractional allelic loss of 0.19. Seven cases showed LOH on at least two markers on chromosomal arm 11p, while six cases showed allelic losses on 11q. The high frequency of LOH on chromosome 11 was also confirmed by analysis of an additional 17 paraffin-embedded AVC. Frequent LOH (50% or greater) was also found on chromosome arms 5q, 6q, 9p, 13, 16p, 17p, and 18p. It can be inferred that the targets of inactivation on chromosomes 5q, 9p, and 17p appear to be APC, p16, and p53, respectively, while the critical target(s) of inactivation at the other frequently lost loci remain to be characterized. The resulting allelotype reveals that distinctive chromosomal alterations are present in these neoplasms, indicating that it is a tumor entity distinct from pancreatic adenocarcinoma.

We have investigated the status of sex chromosomes in 40 pancreatic endocrine tumors (PETs) using 2 complementary techniques: microsatellite and interphase FISH analysis. Twenty-five tumors were from female and 15 from male patients and included 31 nonfunctioning and 9 functioning PET (6 insulinomas, 2 glucagonomas and 1 VIPoma). Microsatellite and FISH analysis showed concordant results in all cases. PETs from females showed frequent loss of chromosome X (40%) whereas PETs from males showed relatively frequent loss of chromosome Y (36%) but never loss of the X chromosome. Statistical analysis showed significant association of sex chromosome loss with metastases (Spearman correlation test, r = 0.5, p < 0.001), local invasion (r = 0.33, p < 0.05) and high proliferation rate measured as Ki-67 index with a 5% cut-off (r = 0.42, p < 0.02). The analysis also showed that local invasion and metastases were highly correlated (r = 0.86). Multivariate survival analysis was therefore carried out including local invasion and loss of sex chromosomes. The presence of local invasion increased the risk of death almost 9 times whereas sex chromosome loss was an independent variable associated with a shorter survival period and an increased risk of death of approximately 4-fold. © 2002 Wiley-Liss, Inc.

Pancreatic endocrine tumors (PETs) occur in association with multiple endocrine neoplasia type 1 (MEN1) and von Hippel-Lindau (VHL) syndromes caused by germline alterations in MEN1 and VHL, respectively. It is thus expected that these genes will also be altered in a proportion of sporadic PETs. Indeed, MEN1 is altered in about 25% of nonfamilial PETs, although no mutations have been found in VHL. For all clinical subtypes, the frequency of allelic loss on chromosome arm 11q mirrors observed mutational frequencies, with the exception of nonfunctional tumors (NF-PETs), in which mutations have been reported in only 8% of cases. As allelic loss on 11q is the most frequent event found in these neoplasms, this low frequency is somewhat puzzling, particularly in light of the fact that most MEN1-associated PETs are nonfunctioning. To clarify the role of these genes in sporadic PETs, we analyzed 31 sporadic NF-PETs, nine insulinomas, and one VIPoma for alterations in MEN1 and VHL. As somatic mutations were observed in eight (26%) of the NF tumors and in one insulinoma, it would therefore appear unlikely that an additional tumor suppressor gene related to sporadic PET pathogenesis is located on 11q. One insulinoma also had a somatic mutation in VHL, and thus this gene may also be altered in these neoplasms, albeit in a small proportion of cases.