High-grade Pancreatic Intraepithelial Neoplasia Research Articles

Presence of Pancreatic Intraepithelial Neoplasia in the Pancreatic Transection Margin does not Influence Outcome in Patients with R0 Resected Pancreatic Cancer

Margin status is one of the strongest prognosticators after resection of pancreatic ductal adenocarcinoma (PDAC). The clinical significance of pancreatic intraepithelial neoplasia (PanIN) at a surgical margin has not been established. A total of 208 patients who underwent R0 resection for PDAC between 2004 and 2008 were selected. Intraoperative frozen section slides containing the final pancreatic parenchymal transection margin were evaluated for presence or absence, number, and grade of PanINs. Data were compared to clinicopathologic factors, including patient survival. PanIN lesions were present in margins in 107 of 208 patients (51.4%). Median number of PanINs per pancreatic resection margin was 1 (range, 1-11). A total of 72 patients had PanIN-1 (34.6%), 44 had PanIN-2 (21.1%), and 16 had PanIN-3 (7.2%) at their margin. Overall median survival was 17.9 (95% confidence interval, 14-21.9) months. Neither the presence nor absence of PanIN nor histological grade had any significant correlation with important clinicopathologic characteristics. There were no significant survival differences between patients with or without PanIN lesions at the resection margin or among patients with PanIN-3 (carcinoma in situ) versus lower PanIN grades. However, patients with R1 resection had a significantly worse outcome compared with patients without invasive cancer at a margin irrespective of the presence of PanIN (P = 0.02). The presence of PanINs at a resection margin does not affect survival in patients who undergo R0 resection for PDAC. These results have significant clinical implications for surgeons, because no additional resection seems to be indicated when intraoperative frozen sections reveal even high-grade PanIN lesions.

Overexpression of fibroblast growth factor receptor 4 in high-grade pancreatic intraepithelial neoplasia and pancreatic ductal adenocarcinoma

The overexpression of fibroblast growth factor receptor (FGFR) 4 has been reported in various human cancers, but it has not been studied in pancreatic ductal adenocarcinoma (PDAC) or its precursor lesion, pancreatic intraepithelial neoplasia (PanIN). Moreover, there is controversy as to whether FGFR4 has a mitogenic role in carcinogenesis or other functions. Therefore, the expression and roles of FGFR4 in pancreatic cancer were investigated. Immunohistochemical staining was performed using an anti-FGFR4 antibody in PDAC and PanIN cases. The expression levels of FGFR4 mRNA and protein were investigated in PDAC cell lines by qRT-PCR and Western blot, respectively. Changes were analyzed in cell morphology, proliferation, migration, invasion and attachment in PDAC cell lines with or without the stimulation of FGFR4 by FGF19, as a known specific ligand. The changes in mRNA levels associated with transformation and tumorigenesis as a result of FGF19 administration were also evaluated. FGFR4 was expressed in 39 of 53 PDAC cases (73.6%) and its expression tended to be related to longer overall survival (P=0.068). Moreover, it was frequently expressed in high-grade PanIN lesions [10 of 11 lesions (90.9%)], whereas it was hardly expressed in low-grade PanIN lesions [1 of 10 lesions (10.0%)] (P=0.0003). FGFR4 stimulation of PDAC cells resulted in significantly increased cell adhesion to laminin and fibronectin (P<0.05) and decreased cell migration (P<0.05). The results of PCR array analysis indicated that this was a result of up-regulation of the integrin α4 family. In contrast, cell morphology or proliferation in PDAC cells was not affected. We showed that FGFR4 expression is markedly increased in high-grade PanIN and PDAC compared with that in normal and low-grade PanIN, and that FGFR4 stimulation by FGF19 of PDAC cells contributes to tumor suppression by increasing cell adhesion to extracellular matrix.

Histologic characteristics of pancreatic intraepithelial neoplasia associated with different pancreatic lesions

Pancreatic intraepithelial neoplasia (PanIN) has been found in association with pancreatic ductal adenocarcinoma, intraductal papillary-mucinous neoplasm (IPMN), mucinous cystic neoplasm, and other pancreatic lesions, but the characteristics of PanINs associated with these lesions are not well characterized. In this study, 185 partial or total pancreatectomy specimens were collected, and 173 had complete slides for reviewed, which included 74 pancreatic ductal adenocarcinomas, 28 IPMNs, 7 mucinous cystic neoplasms, 44 other nonductal tumors, and 20 nontumorous lesions. Differences in grade, extent, and duct involvement among PanINs associated with different lesions were analyzed. Patients with PanINs were older than those without, regardless of associated tumor or lesions. No sex predilection was noted. PanINs were found in 89%, 96%, 86%, 64%, and 55% pancreata with ductal adenocarcinomas, IPMNs, mucinous cystic neoplasm, other nonductal tumors, and nontumorous lesions, respectively. PanIN 1 and 2 were commonly associated with all types of lesions, but high-grade PanIN 3 was more frequently associated with ductal adenocarcinomas. Ductal involvement of PanINs was more extensive in association with ductal adenocarcinomas than in any other types of pancreatic tumors or lesions. PanINs associated with pancreatic ductal adenocarcinomas affected both the main and branched ducts, whereas PanINs associated with other types of pancreatic tumors or lesions were mainly present in the branch ducts. No statistical differences were observed in distribution, extent, and grade of PanINs among IPMNs, mucinous cystic neoplasms, other nonductal tumors, and nontumorous lesions. Our study demonstrated a high concurrence between PanINs and other precancerous lesions and histologic features of PanINs associated with different pancreatic diseases.

Cytologic features of pancreatic intraepithelial neoplasia and pancreatitis: Potential pitfalls in the diagnosis of pancreatic ductal carcinoma

Fine-needle aspiration (FNA) has played a significant role in the diagnosis of pancreatic masses but false-positive diagnoses occur. The Anatomic Pathology files were searched for FNAs of pancreas with subsequent resections. FNAs with a diagnosis of positive for or suspicious for adenocarcinoma followed by a benign resection specimen were reviewed and the surgical pathology and cytology findings correlated. Six cases had a cytologic diagnosis of adenocarcinoma or suspicious for adenocarcinoma but resection specimens were benign. In two cases, a non-invasive intraductal papillary mucinous neoplasm (IPMN) without significant dysplasia was present surrounded by foci of pancreatic intraepithelial neoplasia (PanIN). In both cases, the degree of atypia within the IPMN was less than that seen cytologically. The nuclear features of the PanIN overlapped those seen in the smears. In two cases, a neuroendocrine neoplasm was present accompanied by multifocal PanIN. The cytologic features of the neuroendocrine neoplasm did not correlate with the material cytologically diagnosed as adenocarcinoma. The cytologically atypical epithelium was similar to the PanIN. Two diagnoses of adenocarcinoma were made cytologically but the pancreatectomy specimens revealed pancreatitis with reactive atypia. Cytologic diagnosis of pancreatic adenocarcinoma has high specificity. Six cytologic misdiagnoses of adenocarcinoma occurred in 105 patients. The cytologic features of these misdiagnoses correlated with histopathologic changes of intermediate to high-grade PanIN or marked reactive atypia in severe pancreatitis. PanIN may be an under recognized, but significant source of false-positive results.

LMO2 Is a Novel Predictive Marker for a Better Prognosis in Pancreatic Cancer

PURPOSE: LIM domain only 2 (LMO2) has been identified as a novel oncogene associated with carcinogenesis and better prognosis in several malignant tumors. We investigate the involvement of LMO2 in pancreatic cancer. EXPERIMENTAL DESIGN: We evaluated LMO2 expression in cultured cells, bulk tissues, and microdissected cells from pancreatic cancers by quantitative reverse transcription-polymerase chain reaction and immunohistochemistry. RESULTS: Of 164 pancreatic cancers, 98 (60%) were positive for LMO2 expression. LMO2 was more frequently detected in high-grade pancreatic intraepithelial neoplasia (PanIN) lesions (PanIN-2 and -3) than in low-grade PanIN lesions (PanIN-1A and -1B; P < .001) and was not detected in normal pancreatic ductal epithelium. The LMO2 messenger RNA levels were significantly higher in invasive ductal carcinoma cells than in normal pancreatic cells as evaluated by quantitative reverse transcription-polymerase chain reaction analyses of microdissected cells (P = .036). We also found higher incidence of LMO2 expression in histologic grade G1/G2 cancers than in grade G3 cancers (P < .001). The median survival time of LMO2-positive patients was significantly longer than that of LMO2-negative patients (P < .001), and multivariate analyses revealed that high LMO2 expression was an independent predictor of longer survival (risk ratio, 0.432, P < .001). Even among patients with a positive operative margin, LMO2-positive patients had a significant survival benefit compared with LMO2-negative patients. We further performed a large cohort study (n = 113) to examine the LMO2 messenger RNA levels in formalin-fixed paraffin-embedded samples and found similar results. CONCLUSIONS: LMO2 is a promising marker for predicting a better prognosis in pancreatic cancer.

647 High-Grade Pancreatic Intraepithelial Neoplasia (Panin) Is Associated with Local Recurrence of Pancreatic Adenocarcinoma After “Curative” Surgical Resection

647 High-Grade Pancreatic Intraepithelial Neoplasia (Panin) Is Associated with Local Recurrence of Pancreatic Adenocarcinoma After “Curative” Surgical Resection

Pancreatic Intraepithelial Neoplasia in Heterotopic Pancreas

Morphologic, clinical, and genetic evidence suggests that pancreatic intraepithelial neoplasia (PanIN) is a precursor to ductal adenocarcinoma. But understanding precursor lesions in a pancreas with existing tumor is hampered by the fact that chronic pancreatitis often accompanies carcinoma, and the possible interactions between tumor, chronic pancreatitis, and PanIN are complex. Furthermore, cancerization of ducts can mimic high-grade PanIN. Heterotopic pancreas has a genetic make-up, physiologic function, and local environmental exposure similar to that of the pancreas. It offers an opportunity to study putative precursor lesions in a setting with fewer confounding factors. We identified 6 pancreatic cancer patients who had heterotopic pancreas removed at the time of surgery. All 6 cases were immunostained for p53, cyclin D1, and p16. Molecular analysis of K-ras mutation was also done. All 6 cancer-associated heterotopias had PanIN-1A or 1B; 5 had PanIN-2 and 1 had PanIN-3. Three of 6 cases harbored the same K-ras codon 12 mutation as the PanINs in orthotopic pancreas, and a similar pattern of p53, cyclin D1, and p16 expression was observed between heterotopic and orthotopic pancreas in all 6 cases. There was no chronic pancreatitis in the cancer-associated heterotopias, but chronic pancreatitis was seen adjacent to carcinoma in 5 of 6 cases. The presence of PanIN in heterotopic pancreas from patients with ductal adenocarcinoma supports the progression model.

The RON Receptor Tyrosine Kinase Mediates Oncogenic Phenotypes in Pancreatic Cancer Cells and Is Increasingly Expressed during Pancreatic Cancer Progression

Pancreatic cancer is an aggressive disease characterized by rapid growth and early metastasis. The recepteur d'origine nantais (RON) receptor tyrosine kinase is overexpressed and/or constitutively active in several epithelial cancers, but its role in pancreatic cancer is unknown. In this study, we have characterized RON expression in both murine and human pancreatic cancer. Immunoblotting indicates that RON is expressed in pancreatic intraepithelial neoplasia (PanIN), primary, and metastatic cell lines both in the human and mouse. Immunostaining revealed that 93% of high-grade PanIN, 79% of primary, and 83% of metastatic lesions from human pancreatic tissue samples expressed RON, with minimal expression in normal ducts and low-grade PanIN (6% and 18%, respectively). Moreover, we show a dose-dependent effect of hepatocyte growth factor-like protein (HGFL), the RON-specific ligand, on pancreatic cancer cell migration and invasion, which was reversed by RON inhibition. Although stimulation with HGFL had no effect on proliferation, concurrent RON receptor blockade and gemcitabine treatment increased apoptosis of RON-expressing pancreatic cancer cells versus gemcitabine treatment alone. Finally, HGFL stimulation of pancreatic cancer cells resulted in increased expression of phospho-mitogen-activated protein kinase and phospho-Akt. Taken together, these findings suggest that RON receptor signaling may contribute to pancreatic carcinogenesis, and that further investigation is warranted to assess the potential of RON-directed therapies in this deadly disease.

Intestinal type adenocarcinoma: a previously unrecognized histologic variant of ductal carcinoma of the pancreas

Adenocarcinomas with intestinal differentiation have been described in a wide variety of anatomical sites. To our knowledge, however, ductal adenocarcinomas with intestinal phenotype have not been described in the pancreas. We report here 11 ductal carcinomas of the pancreas that were morphologically similar to colonic adenocarcinomas. These pancreatic carcinomas of intestinal type represented 10% of 110 consecutively removed ductal carcinomas of the pancreas. All intestinal type carcinomas expressed cytokeratin 7, carcinoembryonic antigen, CDX2, and MUC2. The pattern of reactivity of cytokeratin 7 and carcinoembryonic antigen was diffuse, whereas that of mucin 2 staining and CDX2 nuclear labeling was focal and confined predominantly to goblet cells and less frequently to columnar cells. Six carcinomas contained collections of endocrine cells admixed with the columnar and goblet cells. Five carcinomas were associated with high-grade pancreatic intraepithelial neoplasia of intestinal type. Six patients were female and 5 were male. Their ages ranged from 52 to 76 years (mean age, 61 years). The clinical presentation did not differ from that of the conventional ductal carcinomas. All carcinomas originated in the head of the pancreas, and 5 had metastasized to the regional lymph nodes at the time of surgical resection. Only 1 patient survived 5 years. Three patients are disease free from 2.8 to 8.9 months after surgery. Six patients died as a direct result of the carcinomas, and 1 was lost to follow-up. More studies are needed to determine the biologic behavior of this distinctive histologic variant of ductal adenocarcinoma of the pancreas.

Overexpression of cellular inhibitor of apoptosis protein 2 is an early event in the progression of pancreatic cancer

Aim: To determine the role of two antiapoptotic proteins of the inhibitor of apoptosis protein family, cellular inhibitor of apoptosis protein 1 (cIAP1) and cellular inhibitor of apoptosis protein 2...

High-grade pancreatic intraepithelial neoplasia in a patient with familial adenomatous polyposis.

Abstract Familial adenomatous polyposis (FAP) is caused by mutation of the adenomatous polyposis coli (APC) gene and is characterized by multiple colorectal adenomas and tumors of other organs and sites. A 58-year-old woman with FAP syndrome and previous total colectomy presented for routine follow-up examination. Abdominal ultrasound and subsequent endoscopic evaluation revealed ampullary and duodenal polyps, as well as inhomogeneity of the pancreatic head. A pancreaticoduodenectomy confirmed multiple duodenal adenomas. In addition, high-grade pancreatic intraepithelial neoplasia (PanIN-3) was found in the smaller pancreatic ducts. Pancreatic precancerous lesions have only rarely been described in FAP, including 2 pancreatic duct adenomas and 2 intraductal papillary mucinous neoplasms. A review of the world English literature revealed no reports of PanIN-3 in association with FAP. Further studies are required to determine if patients with FAP are at increased risk for pancreatic premalignant lesions.

High-Grade Pancreatic Intraepithelial Neoplasia in a Patient With Familial Adenomatous Polyposis

Familial adenomatous polyposis (FAP) is caused by mutation of the adenomatous polyposis coli (APC) gene and is characterized by multiple colorectal adenomas and tumors of other organs and sites. A 58-year-old woman with FAP syndrome and previous total colectomy presented for routine follow-up examination. Abdominal ultrasound and subsequent endoscopic evaluation revealed ampullary and duodenal polyps, as well as inhomogeneity of the pancreatic head. A pancreaticoduodenectomy confirmed multiple duodenal adenomas. In addition, high-grade pancreatic intraepithelial neoplasia (PanIN-3) was found in the smaller pancreatic ducts. Pancreatic precancerous lesions have only rarely been described in FAP, including 2 pancreatic duct adenomas and 2 intraductal papillary mucinous neoplasms. A review of the world English literature revealed no reports of PanIN-3 in association with FAP. Further studies are required to determine if patients with FAP are at increased risk for pancreatic premalignant lesions.

Quantitative analysis of MUC1 and MUC5AC mRNA in pancreatic juice for preoperative diagnosis of pancreatic cancer

Pancreatic juice is a promising type of diagnostic sample for pancreatic cancer, and members of the mucin (MUC) family are diagnostic candidates. To evaluate the utility of MUC family members as diagnostic markers, we measured MUC mRNA expression in pancreatic tissues and pancreatic juice obtained from patients with different pancreatic diseases as well as in pancreatic cancer cell lines by real-time PCR. Furthermore, to support the possibility of early diagnosis by quantification of MUC1 and MUC5AC, immunohistochemistry and microdissection-based quantitative analysis of mRNA were carried out. There was no significant correlation between MUC1 and MUC5AC expression in cell lines. When beta-actin was used as a reference gene, median MUC1 and MUC5AC mRNA expression levels were remarkably greater in tumoral tissues than in non-tumoral tissues, but median MUC4 and MUC6 mRNA expression levels were not. Receiver operating characteristic curve analysis showed that quantitative analysis of MUC1 and MUC5AC mRNA in pancreatic juice is better diagnostic modality than that of MUC4 and MUC6 mRNA. Immunohistochemistry showed that MUC1 and MUC5AC were highly expressed in invasive ductal carcinomas (IDC) and moderately expressed in high-grade pancreatic intraepithelial neoplasia (PanIN); no staining was observed in normal ducts. Analysis of cells isolated by microdissection showed stepwise upregulation of MUC1 and MUC5AC in the development of high-grade PanIN to IDC. Our results suggest that MUC1 and MUC5AC are upregulated stepwise in pancreatic carcinogenesis and that quantitative assessment of MUC1 and MUC5AC mRNA in pancreatic juice has high potential for preoperative diagnosis of pancreatic cancer.

E-cadherin and β-catenin expression in pancreatic intraepithelial neoplasia and pancreatic adenocarcinoma

Objective: To investigate the significance of abnormal E-cadherin and β-catenin expression in pancreatic intraepithelial neoplasia (PanIN) and pancreatic adenocarcinoma. Methods:Pancreatic samples of 156 cases were retrospectively studied from surgery and autopsy in Changhai hospital from January 2001 to December 2003, from which tissue microarray blocks containing 129 PanIN-1A lesions, 104 PanIN-1B lesions, 22 PanIN-2 lesions, 11 PanIN-3 lesions, and 121 pancreatic ductal adenocarcinomas and corresponding paracancerous tissues were constructed. EnVision method of immunohistochemistry was used to detect the E-cadherin and β-catenin expression. The correlation between the abnormal E-cadherin and β-catenin expression and clinicopathological parameters was analysed. Results: The rate of E-cadherin abnormal expression was significant in ductal adenocarcinomas compared with the PanIN lesions and normal ducts(64.5%,32.3%,0%), moreover, the rate of E-cadherin abnormal expression was in relation to differentiation, lymph node metastasis and perineural invasion of pancreatic adenocarcinoma(P0.05). There was remarkable increase in the E-cadherin cytoplasmic expression in PanIN lesions and ductal adenocarcinomas compared with normal ducts. The rate of β-catenin abnormal expression was found to be related with lymph node metastasis and perineural invasion of pancreatic adenocarcinoma(P0.05). The expression of β-catenin cytoplasm and/or nucleus was significant in high-grade PanIN lesions and ductal adenocarcinomas compared with low grade PanIN lesions or normal ducts(P0.05). There was a positive relationship between the E-cadherin and β-catenin expression in PanIN lesions and ductal adenocarcinomas (P0.01, P0.05). Conclusion: There is aberration in the expression of the E-cadherin and β-catenin in PanIN lesions and ductal adenocarcinomas, suggesting the E-cadherin and β-catenin changes is not only related with the biological action and prognosis, but also involved in pancreatic carcinogenesis.

Overexpression of S100A4 in pancreatic ductal adenocarcinomas is associated with poor differentiation and DNA hypomethylation.

Using the National Center for Biotechnology Information Serial Analysis of Gene Expression database, we found that S100A4, a calcium-binding protein previously implicated in metastasis, was expressed in five of seven pancreatic carcinoma libraries but not in the two normal pancreatic duct libraries. We confirmed the overexpression of S100A4 using reverse transcriptase-polymerase chain reaction, which demonstrated that 18 of 19 (95%) pancreatic carcinoma cell lines expressed S100A4. Using immunohistochemistry, we found that 57 of 61 invasive pancreatic carcinomas (93%), 3 of 18 high-grade pancreatic intraepithelial neoplasia lesions (17%), and 0 of the 69 low-grade pancreatic intraepithelial neoplasia lesions expressed S100A4 protein, whereas normal pancreatic tissue and tissue affected by chronic pancreatitis did not label. Expression of S100A4 was associated with poor differentiation of the pancreatic adenocarcinomas (P = 0.001). We found that three CpG sites in the first intron of the S100A4 gene were approximately 90% methylated in microdissected normal pancreatic duct cells using bisulfite-modified sequencing and in two cell lines and three primary pancreatic carcinomas with a reduced or absent expression of S100A4. In contrast, these CpGs were 100% hypomethylated in 11 of 12 pancreatic cancer cell lines by methylation-specific polymerase chain reaction. The association between the expression of S100A4 and hypomethylation of the first intron of S100A4 was statistically significant (P = 0.002). These data suggest that the majority of pancreatic carcinomas undergo selection for hypomethylation and overexpression of S100A4. Because most pancreatic carcinomas express S100A4, it may be a useful target for early detection strategies.

BRCA2 Is Inactivated Late in the Development of Pancreatic Intraepithelial Neoplasia : Evidence and Implications

Patients harboring germline BRCA2 mutations are at an increased risk of developing pancreatic cancer. We investigated the prevalence of biallelic inactivation of BRCA2 in the presumed precursors to invasive pancreatic ductal carcinomas, pancreatic intraepithelial neoplasia (PanIN). Surgical resection specimens from three patients with germline BRCA2 mutations who developed pancreatic ductal adenocarcinoma were studied. Fourteen PanINs were needle-microdissected from paraffin-embedded tissue. DNA was isolated from these microdissected tissues and amplified by primer-mediated pre-amplification. Loss of heterozygosity at the BRCA2 locus was determined by polymerase chain reaction amplification and cycle sequencing. The presence of the wild-type alleles was evaluated at the nucleotide positions of the germline BRCA2 mutations. The K-ras gene was sequenced at codon 12 and 13 to confirm the efficacy of microdissection. By histological evaluation the prevalence of PanINs in these patients was not notably elevated. Loss of the wild-type allele of BRCA2 was present in one high-grade PanIN (PanIN 3), but in none of 13 low-grade PanINs (PanIN 1). In contrast, K-ras mutations were detectable in 7 of the 14 PanINs. These results suggest that biallelic inactivation of the BRCA2 gene is a relatively late event in pancreatic tumorigenesis. In contrast to classical molecular progression models of tumorigenesis, the inactivation of the wild-type allele in a carrier of a recessive tumor susceptibility gene may not always be the first somatic event during the molecular evolution of a cancer. The necessity for earlier genetic alterations before biallelic inactivation of a recessive tumor susceptibility gene such as BRCA2 may explain why affected carriers have normal numbers of neoplastic precursor lesions, a relatively low phenotypic penetrance, and late age of onset of pancreatic and other cancers.