Search

A disintegrin and metalloproteinase (ADAM) molecules are known for their unique potential to combine adhesion, proteolysis, and signaling. To understand the role of ADAM17/tumor necrosis factor-α (TNF-α) converting enzyme (TACE) in pancreatic ductal adenocarcinoma (PDAC), we investigated its expression, function, and in vitro regulation. ADAM17/TACE mRNA was expressed in 3 of 10 normal pancreatic tissues, 6 of 8 samples from patients with chronic pancreatitis, 10 of 10 PDAC tissues, and 9 of 9 pancreatic cancer cell lines, but it was absent in primary duct epithelial cells. Immunohistochemical staining revealed positive cancer cells in 8 of 10 PDACs but no staining of ducts in normal pancreas. ADAM17/TACE was found in 0 of 16 pancreatic intraepithelial neoplasia (PanIN)-1A lesions, 1 of 30 PanIN-1B lesions, 2 of 13 PanIN-2 lesions but, in 13 of 15 PanIN-3 lesions, associated with PDAC. Western blot, flow cytometry, and confocal microscopy analyses showed the aberrant expression of ADAM17/TACE protein in pancreatic cancer cell lines. The proteolytic activity of ADAM17/TACE, assessed by the release of TNF-α, was inhibited by TNF-α protease inhibitor. ADAM17/TACE gene silencing using small interfering RNA technique in vitro reduced invasion behavior dramatically, whereas proliferation was unaffected. Furthermore, ADAM17/TACE mRNA expression was down-regulated in pancreatic cancer cells arrested in G2-M phase as well as in a time-dependent manner after TNF-α and interleukin-6 incubation. In conclusion, our findings provide evidence of aberrant expression of the proteolytically active ADAM17/TACE in advanced precursor lesions (PanIN-3) and PDAC while identifying its critical involvement in the invasion process. (Cancer Res 2006; 66(18): 9045-53)

S100P is a member of the S100 family of calcium-binding proteins and there have been several recent reports of its overexpression in pancreatic ductal adenocarcinoma (PDAC). We have used Far Western screening and in vitro interaction assays to identify and confirm a novel target protein for S100P. We have named this protein S100PBPR, and shown that its interaction with S100P is dependent on Ca(2+) or Mg(2+). S100PBPR was found to localize to cell nuclei where S100P is also present, and the two proteins co-immunoprecipitate. By in situ hybridization, S100PBPR transcript was found in islet cells but not duct cells of the healthy pancreas. Both S100P and S100PBPR were detected by quantitative real-time polymerase chain reaction in pancreatic intraepithelial neoplasia (PanIN) and PDAC samples, and in situ hybridization revealed the presence of S100PBPR transcript in malignant PDAC cells. These data suggest that an interaction between S100P and S100PBPR may be involved in early pancreatic cancer. S100P was further investigated in PanIN lesions and immunohistochemical analysis showed its expression to correlate significantly with increasing grade of PanINs, being found as early as PanIN-1 with more prevalent expression in PanIN-2 and -3. These data suggest that S100P can be added to the genetic progression model for PDAC.

Autoimmune pancreatitis seems to be a disease with a heterogeneous appearance. Our intention was to establish key diagnostic criteria, define grades of severity and activity, identify features of potential subtypes and evaluate the diagnostic relevance of biopsy specimens.Histopathological criteria and clinical features were recorded in pancreatic resection specimens from 53 patients who were found to have chronic pancreatitis lacking pseudocysts, calculi, irregular duct dilatations, pancreas divisum and/or duodenal wall inflammation. The severity of the chronic inflammation was graded, and the activity of the acute inflammatory component and the granulocytic epithelial lesion (GEL) were determined. Additionally, pancreatic biopsy specimens from 9 patients with suspected AIP were assessed.Periductal lymphoplasmacytic infiltration was identified in all cases, followed in order of frequency by periductal fibrosis and venulitis. These changes were absent in 147 pancreatic specimens that showed chronic pancreatitis associated with pseudocysts, calculi, pancreas divisum and/or duodenal wall inflammation. In 90% of the cases, these chronic changes were graded as 3 or 4. In 81%, the inflammatory process resided in the head of the pancreas and involved the common bile duct. GELs were present in 42% of the patients, who had a mean age of 40.5 years, an almost equal male-female ratio and a high coincidence of ulcerative colitis or Crohn's disease. Patients without GELs were older (mean age 64 years), showed a male preponderance, commonly had Sjogren's syndrome and often developed recurrent bile-duct stenosis. Diagnostically relevant lesions were present in two of five wedge biopsy specimens and three of four fine-needle specimens.Periductal lymphoplasmacytic infiltration and fibrosis, preferential occurrence in the pancreatic head and venulitis characterize autoimmune pancreatitis. GELs predominantly occur in a subset of patients who are younger, more commonly have ulcerative colitis and Crohn's disease and seem to have fewer recurrences than patients without GELs. Pancreatic biopsy material proved to be a very helpful adjunct for establishing the diagnosis.

Gene expression profiling revealed ADAM9 to be distinctly overexpressed in pancreatic ductal adenocarcinoma (PDAC). We examined the relevance of ADAM9 expression in PDAC diagnosis and prognosis. A total of 59 infiltrating PDACs, 32 specimens from patients with chronic pancreatitis, 11 endocrine tumours and 24 acinar cell carcinomas were immunohistochemically analysed for ADAM9 expression. Staining for ADAM9 was detected in 58 out of 59 (98.3%) PDACs and in two out of 24 (8.3%) acinar cell carcinomas, but not in endocrine tumours. In the non-neoplastic pancreas, whether normal or chronically inflamed, ADAM9 was expressed in centroacinar and intralobular duct cells, but not in interlobular duct cells and their hyperplastic lesions. Pancreatic ductal adenocarcinomas showing cytoplasmic ADAM9 expression correlated with poor tumour differentiation and also with shorter overall survival than in cases showing only an apical membranous staining pattern (P=0.001). Multivariate analysis identified cytoplasmic ADAM9 expression as an independent marker of shortened survival in a set of 42 curatively (R0) resected PDAC (P

BACKGROUND Pancreatic ductal adenocarcinomas (PDACs) are extremely rare before age 40 years. The objective of the current study was to determine whether the features of PDACs in patients age < 40 years differ from those in older patients. The authors reviewed the literature and their own files. METHODS The cases reported in the literature were evaluated to determine their precise diagnoses and characteristic features. In a series of 439 PDACs from the authors' files, tumors in patients age 40 years. RESULTS Of 71 pancreatic carcinomas reported in patients age 40 years in their pathologic and molecular findings. Three patients were age ≤ 20 years, and 2 of those patients had a mucinous component with MUC2 positivity. CONCLUSIONS The incidence of PDACs in patients age 40 years, but they seemed to include more variants, particularly mucinous carcinomas. In addition, PDACs in younger patients frequently appeared to be associated with genetic factors. Cancer 2004;100:173–82. © 2003 American Cancer Society

Pancreatic mucinous noncystic (colloid) carcinomas (MNCC) differ from the usual ductal adenocarcinomas in their mucin expression profile and share with many extrapancreatic mucinous carcinomas the expression of MUC2. Because mucinous carcinomas are frequently associated with mutations of the DNA mismatch repair genes, causing them to exhibit the so-called mutator phenotype, we decided to investigate whether MNCCs of the pancreas are characterized by microsatellite instability (MSI). Twelve carcinomas with a mucinous phenotype (8 mucinous noncystic carcinomas, 3 intraductal papillary-mucinous carcinomas with an invasive muconodular component, and 1 ductal adenocarcinoma with an extensive mucinous noncystic component) and 11 ductal adenocarcinomas were immunostained with monoclonal antibodies to the mismatch repair gene products hMLH1, hMSH2, and hMSH6. For MSI analysis, DNA was isolated from microdissected tissue, and five primary microsatellites (BAT 25, BAT 26, D5S346, D17S250, and D2S123) were analyzed. MSI was diagnosed in case a novel allele was found, compared with the normal tissue. The criterion for LOH was a 75% signal reduction. All carcinomas tested exhibited nuclear expression of mismatch repair gene products, except for one MNCC that also showed MSI at the molecular level. The data suggest that pancreatic carcinomas with a mucinous phenotype (MUC2+/MUC1-) do not appear to normally exhibit mutations in the mismatch repair genes and therefore differ in their carcinogenesis from those in other organs.

Intraductal tubulopapillary neoplasms of the pancreas are very rare tumors characterized by intraductal tubulopapillary growth, ductal differentiation, scant intracellular mucin production and cellular dysplasia. Here, we report the first case of an intraductal tubulopapillary neoplasm of the pancreas with clear cell morphology. The tumor was detected during the diagnostic work-up of acute pancreatitis in a 43- year old female. Histological examination revealed a tumor with the typical architecture of an intraductal tubulopapillary neoplasm of the pancreas with tumor cells showing abundant clear cytoplasm and Di-PAS negativity. Immunohistochemistry revealed positivity for Pan-CK, CK7, CK8/18, MUC1, MUC6, carbonic anhydrase IX, CD10, EMA, β-catenin and e-cadherin. Sanger sequencing did not detect mutations for β-catenin, BRAF, KRAS, PIK3CA and GNAS. Altogether, histology, immunohistochemical expression profile (MUC1+, MUC6+, MUC2-, MUC5AC-, thrypsin-, chymotrypsin-, CDX2-) and sequencing results led to the diagnosis of intraductal tubulopapillary neoplasm. However, the neoplasm consisted of cells showing abundant clear cytoplasm, a morphological pattern not being described so far in the current classification of pancreatic intraductal neoplasms. Potential differential diagnosis and the molecular basis of clear cell morphology are discussed. In conclusion, we consider this tumor as intraductal tubulopapillary neoplasm of the pancreas with unique clear cell phenotype. After surgery and without adjuvant therapy, the patient’s clinical course has been uneventful for over two years now. The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1051828790117127

Intraductal papillary-mucinous neoplasms of the pancreas seem to comprise various types, whose relationship to ductal adenocarcinoma and mucinous noncystic carcinoma is unclear. We analyzed the mucin immunophenotype and the DPC4/SMAD4 expression in intraductal papillary-mucinous neoplasms, ductal carcinomas, and mucinous noncystic carcinomas to define features that may help to distinguish between different types of intraductal papillary-mucinous neoplasms and to establish their relationship to other neoplasms of the exocrine pancreas. A series of 51 intraductal papillary-mucinous neoplasms, three mucinous noncystic carcinomas (two with an intraductal component), and 35 ductal adenocarcinomas were screened immunohistochemically for their expression of MUC1, MUC2, MUC5, and DPC4/SMAD4. All intraductal papillary-mucinous neoplasms and mucinous noncystic carcinomas were positive for MUC5. Thirty-two intraductal papillary-mucinous neoplasms and three mucinous noncystic carcinomas abundantly expressed MUC2 but no (or only little) MUC1. The remaining intraductal papillary-mucinous neoplasms showed either mainly MUC1 expression or focal MUC1 and MUC2 expression. All ductal carcinomas but one were MUC2 negative and MUC1 and MUC5 positive. DPC4 was not expressed in two intraductal papillary-mucinous neoplasms that showed a tubular invasion pattern. Twelve of 23 ductal adenocarcinomas were DPC4 positive. Intraductal papillary-mucinous neoplasms can be divided into at least three different mucin immunophenotypes. The first and largest group of intraductal papillary-mucinous neoplasms and mucinous noncystic carcinomas is MUC1 negative and MUC2 positive and probably forms one tumor entity. The second group seems to be related to ductal carcinoma because of its MUC1 positivity in the absence or very weak MUC2 staining. The third group shows focal MUC1/MUC2 expression and is characterized by oncocytic histology.

The presumed precursor lesions of pancreatic ductal adenocarcinoma were recently classified according to their increasing grade of dysplasia and were designated as pancreatic intraepithelial neoplasia (PanIN) 1 through 3. In this study, we tested whether molecular genetic alterations can be correlated with this classification and may help to further categorize the various PanIN grades. We determined the frequencies of allelic loss at chromosomal arms 9p, 17p, and 18q in 81 microdissected duct lesions of various PanIN grades, using a combination of whole genome amplification and microsatellite analysis. In addition we examined the p53 and Dpc4 protein expression patterns by immunohistochemical analysis. In PanIN-1, we did not detect allelic losses. In PanIN-2, allelic losses were found in increasing frequency, and were particularly high in those lesions with moderate-grade dysplasia (low grade, 20, 33, and 17%, loss at 9p, 17p, and 18q, respectively; moderate grade, 46, 77, and 58%). PanIN-3 and invasive carcinomas exhibited abundant losses. Abnormal p53 and Dpc4 protein expression was only rarely identified in PanIN-2 lesions, but occurred frequently in PanIN-3 lesions and invasive carcinomas. The combined genetic and protein expression data support a model in which allelic loss is the first hit in the biallelic inactivation of the p53 and DPC4 tumor suppressor genes. In addition, our data indicate that allelic loss analysis may be useful in separating PanIN-2 lesions with low-grade dysplasia from those PanIN-2 lesions with moderate-grade dysplasia, each potentially representing a distinct progression step toward invasive carcinoma.

Smad4/ DPC4 (deleted in pancreatic carcinoma, locus 4) is a tumor suppressor gene lost at high frequency in cancers of the pancreas and other gastrointestinal organs. Smad4 encodes a key intracellular messenger in the transforming growth factor β (TGF-β) signaling cascade. TGF-β is a potent inhibitor of the growth of epithelial cells; thus, it has been assumed that loss of Smad4 during tumor progression relieves this inhibition. Herein, we show that restoration of Smad4 to human pancreatic carcinoma cells suppressed tumor formation in vivo , yet it did not restore sensitivity to TGF-β. Rather, Smad4 restoration influenced angiogenesis, decreasing expression of vascular endothelial growth factor and increasing expression of thrombospondin-1. In contrast to the parental cell line and to control transfectants that produced rapidly growing tumors in vivo , Smad4 revertants induced small nonprogressive tumors with reduced vascular density. These data define the control of an angiogenic switch as an alternative, previously unknown mechanism of tumor suppression for Smad4 and identify the angiogenic mediators vascular endothelial growth factor and thrombospondin-1 as key target genes.

Design: It was the aim of this study to investigate the influence of extended retroperitoneal tissue clearance on long-term survival in patients with ductal adenocarcinoma of the head of the pancreas. Patients and methods: From 10/1988 to 3/1998 a prospective observation study was initiated in 108 patients with malignant growth in the head of the pancreas to compare patients with regional lymphadenectomy (RLA) versus extended retroperitoneal tissue clearance (ELA). In 36 patients other tumors than ductal adenocarcinomas were found, so that 72 patients with a partial pancreaticoduodenectomy and a histologically established diagnosis of ductal adenocarcinoma were included. Pancreaticoduodenectomy was combined with RLA in 26 cases and with ELA in 46 patients. Results: Comparing only R0-resected patients (n=58) no significant difference in long-term survival rates between the RLA and the ELA group was found. Hospital mortality was 3.8% in the RLA group and 6.5% in the ELA group. Significant or nearly significant results were shown for the following parameters: Stage of the disease: Patients after partial pancreaticoduodenectomy of a stage I/II cancer of the head of the pancreas showed a 63% 5-year survival rate compared to 15% in patients in stage III or IV (p=0.0087). Grading: No patient with a poorly differentiated ductal adenocarcinoma of the head of the pancreas survived the first year in comparison to 55% of patients with well or moderately differentiated tumors (p=0.0022). N-stage: 5-year survival of patients in NO stage was 46.9% and 15% for NI stage patients (p=0.081). Portal vein infiltration: No patient with a RO-resection and histologically proven tumor infiltration of the portal vein survived the first year whereas 63% of patients did so after curative resection without portal vein involvement (p=0.0063). Conclusion: Out data indicate that extensive retroperitoneal tissue clearance does not improve long-term survival rates compared to regional lymphadenectomy restricted to the right side of the mesenteric artery.

Cystic lesions of the pancreas are increasingly recognized. While some lesions show benign behaviour (serous cystic neoplasm), others have an unequivocal malignant potential (mucinous cystic neoplasm, branch- and main duct intraductal papillary mucinous neoplasm and solid pseudo-papillary neoplasm). European expert pancreatologists provide updated recommendations: diagnostic computerized tomography and/or magnetic resonance imaging are indicated in all patients with cystic lesion of the pancreas. Endoscopic ultrasound with cyst fluid analysis may be used but there is no evidence to suggest this as a routine diagnostic method. The role of pancreatoscopy remains to be established. Resection should be considered in all symptomatic lesions, in mucinous cystic neoplasm, main duct intraductal papillary mucinous neoplasm and solid pseudo-papillary neoplasm as well as in branch duct intraductal papillary mucinous neoplasm with mural nodules, dilated main pancreatic duct >6 mm and possibly if rapidly increasing in size. An oncological partial resection should be performed in main duct intraductal papillary mucinous neoplasm and in lesions with a suspicion of malignancy, otherwise organ preserving procedures may be considered. Frozen section of the transection margin in intraductal papillary mucinous neoplasm is suggested. Follow up after resection is recommended for intraductal papillary mucinous neoplasm, solid pseudo-papillary neoplasm and invasive cancer.

Between September 1991 and December 1993, 253 patients were operated on using the Classical Intrafascial SEMM (Serrated Edged Macro Morcellator) Hysterectomy (CISH) technique. One hundred fifty-two patients were assigned to pelviscopic CISH and 101 to laparotomic CISH. Uterine leiomyomas with menstrual disorders and pressure symptoms topped the list of indications with 61%. In all cases, initially transuterine mucosal resection and coring of the cervicouterine cylinder were carried out followed by the intrafascial supracervical dissection of the uterus. The size of the uterus played a decisive role in selecting the cases for CISH technique either by pelviscopy or laparotomy. The cervicouterine mucosal cylinders were cored using the Calibrated Uterine Resection Tool (CURT). Cervical thickness and diameters were measured preoperatively by transvaginal sonography for facilitating the use of a specific-sized CURT. After removal of this cylinder, hemostasis in the area was secured by coagulating with an endocoagulation device. The advantage of this technique is that the pelvic floor integrity remains intact, and because uterine arteries and ureters were not touched, the so called “complication zone” is thus avoided.The histological findings are in agreement with the indications, the leiomyomas and leiomyomas with adenomyosis being the most frequent pathology. The histologic analysis showed that in all cases the squamocolumnar transformation zone was totally removed. There were 11 (4.4%) complications, promptly identified and treated without further problems.The value of the Classical intrafascial supracervical hysterectomy without colpotomy including the resection of transformation zone speaks for itself, because there is less physical stress and recovery is quick. However, it has yet to prove its value as compared with other techniques for hysterectomy for specific indications.

Background: MicroRNAs (miRNAs) are RNA molecules that are involved in the regulation of many cellular processes, including those related to human cancers. The aim of this study was to determine, as a proof of principle, whether specific candidate miRNAs could be detected in fine-needle aspirate (FNA) biopsies of pancreatic ductal adenocarcinoma (PDAC) and could accurately differentiate malignant from benign pancreatic tissues. Methods: We used TaqMan® assays to quantify miRNA levels in FNA samples collected in RNARetain (n = 16) and compared the results with a training set consisting of frozen macrodissected pancreatic samples (n = 20). Results: Quantitative reverse-transcription PCR analysis confirmed that miRNA levels are affected in PDAC FNAs and correlate well with the changes observed in the training set of frozen pancreatic samples. Analysis of the amounts produced for a few specific miRNAs enabled identification of PDAC samples. The combination of miR-196a and miR-217 biomarkers further improved the ability to distinguish between healthy tissue, PDAC, and chronic pancreatitis in the training set (P = 8.2 × 10−10), as well as segregate PDAC FNA samples from other FNA samples (P = 1.1 × 10−5). Furthermore, we showed that miR-196a production is likely specific to PDAC cells and that its incidence paralleled the progression of PDAC. Conclusions: To the best of our knowledge, this study is the first to evaluate the diagnostic potential of miRNAs in a clinical setting and has shown that miRNA analysis of pancreatic FNA biopsy samples can aid in the pathologic evaluation of suspicious cases and may provide a new strategy for improving the diagnosis of pancreatic diseases.

Several diverse genetically engineered mouse models of pancreatic exocrine neoplasia have been developed. These mouse models have a spectrum of pathologic changes; however, until now, there has been no uniform nomenclature to characterize these changes. An international workshop, sponsored by The National Cancer Institute and the University of Pennsylvania, was held from December 1 to 3, 2004 with the goal of establishing an internationally accepted uniform nomenclature for the pathology of genetically engineered mouse models of pancreatic exocrine neoplasia. The pancreatic pathology in 12 existing mouse models of pancreatic neoplasia was reviewed at this workshop, and a standardized nomenclature with definitions and associated images was developed. It is our intention that this nomenclature will standardize the reporting of genetically engineered mouse models of pancreatic exocrine neoplasia, that it will facilitate comparisons between genetically engineered mouse models and human pancreatic disease, and that it will be broad enough to accommodate newly emerging mouse models of pancreatic neoplasia. (Cancer Res 2006; 66(1): 95-106)

Pancreatic ductal adenocarcinoma is the eighth most common cancer with the lowest overall 5-year relative survival rate of any tumor type today. Expression profiling using microarrays has been widely used to identify genes associated with pancreatic cancer development. To extract maximum value from the available gene expression data, we applied a meta-analysis to search for commonly differentially expressed genes in pancreatic ductal adenocarcinoma. We obtained data sets from four different gene expression studies on pancreatic cancer. We selected a consensus set of 2984 genes measured in all four studies and applied a meta-analysis approach to evaluate the combined data. Of the genes identified as differentially expressed, several were validated using RT–PCR and immunohistochemistry. Additionally, we used a class discovery algorithm to identify a gene expression signature. Our meta-analysis revealed that the pancreatic cancer gene expression data sets shared a significant number of up- and downregulated genes, independent of the technology used. This interstudy crossvalidation approach generated a set of 568 genes that were consistently and significantly dysregulated in pancreatic cancer. Of these, 364 (64.1%) were upregulated and 204 (35.9%) were downregulated in pancreatic cancer. Only 127 (22%) were described in the published individual analyses. Functional annotation of the genes revealed that genes presumably associated with the cell adhesion-mediated drug resistance pathway are frequently overexpressed in pancreatic cancer. Meta-analysis is an important tool for the identification and validation of differentially expressed genes. These could represent good candidates for novel diagnostic and therapeutic approaches to pancreatic cancer.

Recent studies have reported elevated levels of S100A6 in pancreatic ductal adenocarcinoma cells. Here, we describe a detailed analysis of S100A6 expression in benign (n = 32), malignant (n = 60), and premalignant pancreatic ductal cells [96 pancreatic intraepithelial neoplasias (PanIN) from 46 patients]. S100A6 staining was more intense in malignant cells than in benign cells (P = 0.0001). In malignant cells, staining was higher in the nucleus than in the cytoplasm (P = 0.003). Univariate analysis revealed a significant decrease in survival time for patients with high levels of nuclear (P = 0.01) but not cytoplasmic (P = 0.20) S100A6. No evidence was found for an association between nuclear S100A6 expression and other variables, including gender, age at surgery, tumor size or grade, nodal metastases, resection margin, vascular invasion, perineural invasion, p53 or Smad4 levels (both linked to survival in previous studies), or the p65 subunit of nuclear factor-κB (a potential regulator of S100A6). Although nodal metastases and resection margin involvement were also associated with poor survival (P = 0.06 in both cases), multivariate analysis suggests that nuclear S100A6 is a significant independent indicator of survival (P = 0.003). Whereas PanIN 1a lesions showed a general absence of S100A6 staining, there was a progressive increase in the proportion of positively stained PanINs with increasing PanIN grade. In particular, we observed an increase in the frequency and intensity of nuclear staining. Our results suggest that up-regulation of S100A6 is an early event in pancreatic cancer development and that elevated levels of nuclear S100A6 may affect clinical outcome.

In recent years, autoimmune pancreatitis has been established as a special type of chronic pancreatitis. It is characterized by its histopathological and immunological features. The morphological hallmarks are periductal infiltration by lymphocytes and plasma cells and granulocytic epithelial lesions with consequent destruction of the duct epithelium and venulitis. Autoimmune pancreatitis has therefore also been called lymphoplasmacytic sclerosing pancreatitis, duct-destructive chronic pancreatitis, or sclerosing pancreatitis. Autoimmune pancreatitis most commonly involves the head of the pancreas and the distal bile duct. Occasionally, masses are formed and it has been described as an inflammatory myofibroblastic tumor.

The goal of this study was to evaluate the consistency of distinction between pancreatic intraepithelial neoplasia (PanIN) and intraductal papillary-mucinous neoplasms (IPMN) and the hypothesis that guidelines for their distinction might be inadequate.A group of 93 pancreas specimens from surgical resections or autopsies that contained lesions consistent with histopathological diagnoses of PanIN-1A, PanIN-1B, PanIN-2, or IPMN (adenoma or borderline) was collected. The classification of these neoplasms by 6 pathologists, 2 from Europe, 2 from Japan, and 2 from the United States, was compared. The pathologists initially used guidelines current in their practice and then reviewed 47 of the 93 specimens a second time using new consensus definitions and guidelines for PanIN and IPMN that were developed in 2003.The initial comparison showed frequent disagreement regarding both category and grade of the lesions. Agreement was greater for category than grade. In the second review, agreement among the 6 reviewers improved, remaining higher for category, although disagreements persisted for both category and grade.We conclude that the new definitions of PanIN and IPMN improve the consistency in classifying these lesions, but additional work is needed to further improve the reproducibility of their classification.

Profiles of gene transcription have begun to delineate the molecular basis of ovarian cancer, including distinctions between carcinomas of differing histology, tumor progression and patient outcome. However, the similarities and differences among the most commonly diagnosed noninvasive borderline (low malignant potential, LMP) lesions and invasive serous carcinomas of varying grade (G1, G2 and G3) have not yet been explored. Here, we used oligonucleotide arrays to profile the expression of 12,500 genes in a series of 57 predominantly stage III serous ovarian adenocarcinomas from 52 patients, eight with borderline tumors and 44 with adenocarcinomas of varying grade. Unsupervised and supervised analyses showed that LMP lesions were distinct from high-grade serous adenocarcinomas, as might be expected; however, well-differentiated (G1) invasive adenocarcinomas showed a strikingly similar profile to LMP tumors as compared to cancers with moderate (G2) or poor (G3) cellular differentiation, which were also highly similar. Comparative genomic hybridization of an independent cohort of five LMP and 63 invasive carcinomas of varying grade demonstrated LMP and G1 were again similar, exhibiting significantly less chromosomal aberration than G2/G3 carcinomas. A majority of LMP and G1 tumors were characterized by high levels of p21/WAF1, with concomitant expression of cell growth suppressors, gadd34 and BTG-2. In contrast, G2/G3 cancers were characterized by the expression of genes associated with the cell cycle and by STAT-1-, STAT-3/JAK-1/2-induced gene expression. The distinction between the LMP-G1 and G2-G3 groups of tumors was highly correlated to patient outcome (chi(2) for equivalence of death rates=7.681189; P=0.0056, log-rank test). Our results are consistent with the recent demonstration of a poor differentiation molecular 'meta-signature' in human cancer, and underscore a number of cell-cycle- and STAT-associated targets that may prove useful as points of therapeutic intervention for those patients with aggressive disease.

Large-scale gene expression analyses of microdissected primary tissue are still difficult because generally only a limited amount of mRNA can be obtained from microdissected cells. The introduction of the T7-based RNA amplification technique was an important step to reduce the amount of RNA needed for such analyses. This amplification technique produces amplified antisense RNA (aRNA), which so far has precluded its direct use for serial analysis of gene expression (SAGE) library production. We describe a method, termed ‘aRNA-longSAGE’, which is the first to allow the direct use of aRNA for standard longSAGE library production. The aRNA-longSAGE protocol was validated by comparing two aRNA-longSAGE libraries with two Micro-longSAGE libraries that were generated from the same RNA preparations of two different cell lines. Using a conservative validation approach, we were able to verify 68% of the differentially expressed genes identified by aRNA-longSAGE. Furthermore, the identification rate of differentially expressed genes was roughly twice as high in our aRNA-longSAGE libraries as in the standard Micro-longSAGE libraries. Using our validated aRNA-longSAGE protocol, we were able to successfully generate longSAGE libraries from as little as 40 ng of total RNA isolated from 2000–3000 microdissected pancreatic ductal epithelial cells or cells from pancreatic intraepithelial neoplasias.

Cystic lesions and neoplasms of the pancreas are uncommon, but they are of special interest because they can usually be cured by resection. During the last decade, the spectrum of these tumors has increased considerably. We present a series of five cystic lesions of the pancreas that differ from all categories described so far. The patients affected by these tumors were three men and two women (mean age, 57 y). Four lesions were unifocal and involved the head of the pancreas; one was multifocal and involved the pancreatic head and tail. Grossly, these tumors presented as unilocular or multilocular thin-walled cysts that contained turbid fluid, or, in two cases, blood, and lacked any communication with the duct system. Microscopically, the cysts were lined by cuboidal to columnar mucin-producing cells, supported by a small band of dense fibrous stroma. Immunocytochemically, the epithelial cells were positive for cytokeratins 7, 8, 18, 19, and 20 (except one), and Ca 19-9 but were negative for trypsin, CEA, synaptophysin, chromogranin A, calretinin, and alpha-inhibin. In four of the five lesions, the epithelial cells expressed MUC5AC, and in one of the five, MUC1. MUC2 and MUC6 were not expressed in any of the lesions. The stromal cells lacked the nuclear progesterone positivity that is typical of mucinous cystic neoplasms. During a mean follow-up period of 2 years, there were no recurrences or cases of malignant transformation after resection. The results suggest that these cystic lesions are distinct from mucinous cystic neoplasms, the most important entity in the differential diagnosis. Because they may represent a nonneoplastic cystic change of the pancreas, we propose the descriptive term mucinous nonneoplastic cyst for these tumors of unknown pathogenesis.

BACKGROUND Chronic pancreatitis (CP) is considered to be a risk factor for the development of pancreatic carcinoma. The detection of K-ras mutations in the duodenal or pancreatic juice has been held to be a reliable tool for its early diagnosis. However, K-ras mutations also occur in hyperplastic ductal epithelium, making it difficult to interpret their role in pancreatic carcinogenesis. METHODS The study included 30 resection specimens, 15 from patients with alcoholic CP, and 15 from patients with idiopathic CP. The mean duration of disease was 6.8 years. A total of 429 ductal lesions were classified according to the World Health Organization classification (1996) and microdissected. K-ras analysis was performed by means of polymerase chain reaction (45 cycles), constant denaturing gel electrophoresis, and sequencing. Immunostaining was performed with antibodies against p53, Ki-S5, carcinoembryonic antigen, and two types of mucins. RESULTS The 30 specimens demonstrated all types of ductal lesions. Severe cellular atypia was not observed. A total of 429 ductal lesions were analyzed. Approximately 4.4% of the lesions (19 of 429) from 27% of the patients (8 of 30) showed K-ras mutations, but they were unrelated to the duration or type of CP. Immunostaining for mutated p53 protein always was negative. Increased proliferative activity was noted only in patients with papillary hyperplasia. No patient developed pancreatic carcinoma within a follow-up period of at least 3 years. CONCLUSIONS Ductal lesions in patients with CP exhibit K-ras mutations without additional indications of neoplastic transformation such as severe dysplasia or mutated p53 protein. Therefore, for diagnostic and therapeutic purposes, the detection of K-ras mutations should be supplemented by the demonstration of additional genetic alterations or clinical signs of malignancy. Cancer 2000;88:2495–504. © 2000 American Cancer Society.

Introduction In recent years a type of chronic pancreatitis has been described that is clearly distinct from alcoholic chronic pancreatitis. It is characterized by its special pathology, immunologic features, clinical presentation, and steroid responsiveness. Because of its histologic hallmarks, i.e., ductal and periductal infiltration by lymphocytes, plasma cells, and granulocytes, it has been called duct-destructive chronic pancreatitis. The frequent association of this type of pancreatitis with other autoimmune diseases such as Sjogren's disease and a number of other immune phenomena has led to the concept that it is an autoimmune disease. Hence, the term autoimmune pancreatitis has been introduced and will be used in this review. Aims This review focuses on the pathology and related clinical and immunologic features of this new type of pancreatitis. Conclusions As the ability to diagnose autoimmune pancreatitis on the basis of clinical, imaging, and laboratory findings improves, it seems likely that fewer patients with this diagnosis will undergo resection. Thus, there is a need to accumulate and study additional retrospective series of patients undergoing resection because of mass-forming chronic pancreatitis.