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T1373 New Predictive Factors for Malignancy of Intraductal Papillary Mucinous Neoplasms of the Pancreas, Mucopolysaccharides in the Mucin of Pancreatic Mucus is Useful?
AGA Abstracts
who have undergone an Endoscopic Ultrasound(EUS) procedure at H. Lee Moffitt Cancer Center. 87 patients were included in the analysis with surgical resections from 2000-2009. From this population we included all patients who had preoperative cyst fluid CEA levels obtained by EUS-Guided FNA recorded. One-way ANOVA was performed to examine the differences of CEA levels among pathologic stages. Results: 47 patients (32 men) underwent preoperative EUS-FNA and surgical resection of an IPMN. The mean level of CEA increased as the pathology worsened from no dysplasia (adenoma) to high-grade dysplasia (Carcinoma in situ). Surprisingly, once invasive cancer developed the CEA level markedly decreased to levels comparable to the most benign surgical pathology. Furthermore, there was no difference in CEA levels with statistical significance between pathologic stages (p = 0.35). The Fluid CEA levels and corresponding surgical pathologic diagnoses are summarized in the table below. Conclusion: Based on this retrospective study, a markedly elevated cyst fluid CEA level was not an accurate predictor of invasive cancer in surgically resected IPMNs. In contrast, the appearance of invasive cancer in an IPMN lesion is associated with a decline in mean CEA level and there was no statistical significant difference in the CEA levels between the pathologic groups. Therefore the decision not to resect a cystic lesion should not be based solely on the observation that the CEA is low. Larger studies are needed to better define the role of cyst fluid CEA level in the management of pancreatic IPMNs.
which was a microinvasive carcinoma. Discussion: In the case of branch duct IPMNs, resection should be indicated if the mural nodule is at least 10 mm or the cyst size is at least 5 cm with the mural nodule size of at least 5 mm. The present findings suggest that a wait-and-see approach can be taken even when the cyst size is 30 mm or more, provided there is no mural nodule. However, careful follow-up is necessary since some patients show enlargement or appearance of mural nodules with the passage of time. T1373 New Predictive Factors for Malignancy of Intraductal Papillary Mucinous Neoplasms of the Pancreas, Mucopolysaccharides in the Mucin of Pancreatic Mucus is Useful? Yoshikazu Toyoki, Kenichi Hakamada [Background/Aim] Intraductal papillary-mucinous neoplasmas (IPMNs) of the pancreas has a wide range of malignant potentials in which the preoperative accurate diagnosis of carcinoma still remains challenging. The aim of this study is to determine predictive indicators for malignant lesion in IPMNs. We focused on mucopolysaccharides in mucin of pancreatic juice from IPMNs. [Patients]Medical records of 44 patients with IPMNs operated on between 1990 and 2006 at our department were reviewed retrospectively. For examination of mucopolysaccharides in mucin, the specimen of IPMNs patients were stained by alcian-blue (pH 2.5 and 1.0) and PAS. The presence of acidic mucopolysaccharides in pancreatic mucin was determined by alcian-blue staining, the presence of neutral mucopolysaccharides in pancreatic mucin was determined by PAS staining. [Results] Seventeen patients had adenocarcinoma (including carcinoma in situ), 27 benign tumors. The five-year survival rate of the patients with benign tumors was 96.0%, and that of the patients with carcinoma was 73.7%. First, we examined risk factors for malignancy of these patients by preoperative imaging study (computed tomography, ultrasonography, pancreaticography and so on). By univariate analysis, Diameters of the main pancreatic duct and the presence of mural nodules were associated with malignancy (p=0.0009, p=0.004). However, there were no predictive factors for malignant tumors by multivariate analysis. Second, we determined the sugar chain in pancreatic mucin for examination of biological function by clinicopathological study, the patients of positive staining of alcian-blue (pH 2.5 and 1.0) were more frequent malignancy than that of negative staining (p=0.017, p=0.0041). The patients of positive staining of PAS were more frequent benign tumors than that of negative staining (p=0.044). [Conclusion]Our data suggested that it was difficult to diagnose as the malignancy of IPMNs by preoperative imaging study. We focused on sugar chains in mucin of pancreatic juice from IPMNs. The presence of acidic mucopolysaccharides was associated with malignancy. We plan to analysis of the acidic mucopolysaccharides in pancreatic juice from preoperative patients with IPMNs.
T1371 Intraductal Papillary Mucinous Neoplasms and Extrapancreatic Malignancies: Is it a Real Association or Just a Coincidence? Kazumichi Kawakubo, Minoru Tada, Suguru Mizuno, Hiroshi Yagioka, Takashi Sasaki, Hirofumi Kogure, Yousuke Nakai, Kenji Hirano, Naoki Sasahira, Hiroyuki Isayama, Kazuhiko Koike Background & Aims: Intraductal papillary mucinous neoplasms (IPMN) of the pancreas has been reported to be associated with extrapancreatic malignancies, but there have been no prospective studies evaluating the incidence of extrapancreatic cancers in patients with IPMN. In this study, we prospectively examined the frequency of developing extrapancreatic cancers after diagnosis of IPMN. Methods: All patients with IPMN diagnosed at Tokyo University Hospital from 1995 to 2008 were identified. After excluding patients with preexisting and concomitant extrapancreatic malignancies, a total of 777 patients with IPMN were prospectively followed up for 3.5 years on average. We compared the incidence of observed each extrapancreatic malignancies with the expected incidence of age-gendermatched general Japanese population by using the Vital statistics of Japan. Results: Extrapancreatic cancers developed in 38 of 777 patients with IPMN during the period (1.38% per year). The most common malignancies were hepatocellular (n = 7), colorectal (n = 6), prostate (n = 4), gastric (n = 4), and lung cancers (n = 4). The calculated standardized incidence rate of each malignancies were as follows (95% Confidence interval); hepatocellular 2.90 (0.75-5.05), colorectal 1.07 (0.21-1.94), prostate 1.08 (0.02-2.13), gastric 0.56 (0.011.11), and lung cancers 084 (0.02-1.66). During the same period, pancreatic cancer developed in 13 patients, with a standardized incidence rate of 9.57 (4.37-14.77). Conclusions: Our results shows that, contrary to several recent reports, the incidence of extrapancreatic malignancies in patients with IPMN is equal to that in general population, whereas the incidence of pancreatic cancer is high. Further prospective studies are needed to elucidate the clinical course of the patients with IPMN.
T1374 EZH2 Knock Down by Lentiviral shRNA Inhibits Pancreatic Ductal AdenoCarcinoma Cell Proliferation In Vitro and Tumor Growth In Vivo Ramesh B. Batchu, Aamer Qazi, Shelly Seward, Masood A. Shammas, Sreedhar Chamala, Assaad Semaan, Christopher P. Steffes, Donald W. Weaver Background: Enhancer of zeste homologue 2 (EzH2) is a component of chromatin modification protein complex with methyl transferase activity. EzH2 is up regulated in various cancers and has been proposed to be a marker of aggressive phenotype. High levels of EzH2 have been observed in pancreatic ductal adeno-carcinoma (PDAC), however its role in disease progression is not well understood. Diseases, for which an abnormal gene function can be attributed as a cause, can be potentially treatable using gene silencing with short interfering RNA (siRNA). In proliferating cells such as cancer cells, siRNA activity is short lived. To get around this problem, lentiviral vector-based systems for the introduction and stable expression of siRNA in target cells have been developed. In this system, siRNA cassette is driven by U6 RNA polymerase III promoter that express sense and antisense strands separated by short hairpin RNAs (shRNAs) that are cleaved by the Dicer to generate continuous supply of siRNA In Vivo. Here we investigated potential role of EzH2 in PDAC by lentiviral shRNA mediated knock down of EzH2 to understand its contribution in the tumor progression. We further evaluated the ability of EzH2 depleted PDAC cells to form tumors in CB17/ICrSCID mice In Vivo. Methods: PANC-1 and MiaPaca-2 cell lines were transduced with lentiviral EzH2 shRNA (sense sequence of the shRNA in the vector: 5' CCG GCC CAA CAT AGA TGG ACC AAA TCT CGA GAT TTG GTC CAT CTA TGT TGG GTT TTT G 3). Standard protocols were followed for western blot analysis of EzH2 levels after lentiviral transduction. Triplicate growth curves were generated with cell counting kit-8 (CCK-8, Dojindo scientific). Approximately million PANC-1 cells transduced with lentiviral EzH2 shRNA were injected subcutaneously into CB17/ICr-SCID mice for tumor xenograft studies. Results: Significant down-modulation of EzH2 was observed in MiaPaca-2 cells and PANC-1 cells after lentiviral transduction. Further, we observed reduction in the cell proliferation of both PANC-1 and MiaPaca-2 cell lines in response to EzH2 knock down by lentiviral shRNA transduction. The ability of PANC-1 cells to produce palpable tumors after EzH2 knockdown in CB17/ ICr-SCID mice was reduced by over 80% compared to control cells indicating not only that EzH2 is needed for the growth of PDAC In Vivo but also the efficiency of lentiviral shRNA particles. Conclusions: The results indicate that the lentiviral shRNA mediated EzH2 epigenetic silencing may be a potential therapeutic strategy for PDAC.
T1372 Indication for Resection of Pancreatic Branch Duct Intraductal Papillary Mucinous Neoplasms: Reconsideration on the Basis of Analysis of Resected and Conservatively Followed up Cases Hiroko Nebiki, Koichi Taira, Shiba Masatugu, Reiko Ashida, Tetsuo Arakawa Objective: The International Consensus Guidelines for Management of Intraductal Papillary Mucinous Neoplasms of the Pancreas state that appearance of symptoms attributable to the cyst, presence of intramural nodules, cyst size > 30 mm, dilatation of the main pancreatic duct (>6mm) would be indications for resection of branch duct IPMNs. They also state that further study is needed to determine if all branch duct IPMNs > 30 mm in size should be resected immediately. No clear statement is made with regard to the size of mural nodules. In our hospital, resection is indicated for branch duct IPMNs if there is a mural nodule of at least 5 mm in size, if the main pancreatic duct diameter is at least 6 mm, or if symptoms are present. A wait-and-see approach is taken for all other cases of branch duct IPMNs. We reconsidered the surgical indications for branch duct IPMNs on the basis of an analysis of resected cases and conservatively followed up cases. Patients and Methods: Between January 1996 and September 2009, we encountered 109 patients with branch duct IPMNs, consisting of 24 who underwent resection and 85 who were managed conservatively. The 24 resected cases consisted of 11 cases of adenoma and 13 of cancer. Analysis of resected cases: Mural nodules of >5 mm were found in 13 cancer cases and 4 adenoma cases, while nodules of >10 mm were found in 9 patients, all of whom had cancer. A main pancreatic duct diameter of >6 mm was seen in 4 patients, all of whom had cancer. Cyst size exceeded 30 mm in 21 patients, 12 of whom had cancer, and it exceeded 50 mm in 8 patients, 7 of whom had cancer. A mural nodule size of at least 5 mm but less than 10 mm was observed in 8 patients, and all 3 of those patients who had a cyst size of at least 5 cm had cancer. Analysis of dfollowed-up cases: There were 6 patients with no mural nodules despite having a cyst with a size of at least 30 mm and who were managed conservatively. These included 3 in whom there was almost no enlargement and also no development of nodules. One patient was monitored for 7 years and underwent resection due to development of a mural nodule,
AGA Abstracts
T1375 Expression of Mir-101 Inhibits Cell Growth and Proliferation by Down Regulation of EZH2 in PANC-1 Cells Both In Vitro and In Vivo Ramesh B. Batchu, Aamer Qazi, Assaad Semaan, Sreedhar Chamala, Shelly Seward, Christopher P. Steffes, Masood A. Shammas, Donald W. Weaver Objectives: MicroRNAs (miRNA) are 22-nucleotide highly conserved non-coding RNA molecules that enhance mRNA degradation and translational repression of target genes. Although identified relatively recently, miRNAs have been recognized as major players in gene expression. Emerging evidences strongly suggest a crucial role played by miRNA-mRNA interaction
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who have undergone an Endoscopic Ultrasound(EUS) procedure at H. Lee Moffitt Cancer Center. 87 patients were included in the analysis with surgical resections from 2000-2009. From this population we included all patients who had preoperative cyst fluid CEA levels obtained by EUS-Guided FNA recorded. One-way ANOVA was performed to examine the differences of CEA levels among pathologic stages. Results: 47 patients (32 men) underwent preoperative EUS-FNA and surgical resection of an IPMN. The mean level of CEA increased as the pathology worsened from no dysplasia (adenoma) to high-grade dysplasia (Carcinoma in situ). Surprisingly, once invasive cancer developed the CEA level markedly decreased to levels comparable to the most benign surgical pathology. Furthermore, there was no difference in CEA levels with statistical significance between pathologic stages (p = 0.35). The Fluid CEA levels and corresponding surgical pathologic diagnoses are summarized in the table below. Conclusion: Based on this retrospective study, a markedly elevated cyst fluid CEA level was not an accurate predictor of invasive cancer in surgically resected IPMNs. In contrast, the appearance of invasive cancer in an IPMN lesion is associated with a decline in mean CEA level and there was no statistical significant difference in the CEA levels between the pathologic groups. Therefore the decision not to resect a cystic lesion should not be based solely on the observation that the CEA is low. Larger studies are needed to better define the role of cyst fluid CEA level in the management of pancreatic IPMNs.
which was a microinvasive carcinoma. Discussion: In the case of branch duct IPMNs, resection should be indicated if the mural nodule is at least 10 mm or the cyst size is at least 5 cm with the mural nodule size of at least 5 mm. The present findings suggest that a wait-and-see approach can be taken even when the cyst size is 30 mm or more, provided there is no mural nodule. However, careful follow-up is necessary since some patients show enlargement or appearance of mural nodules with the passage of time. T1373 New Predictive Factors for Malignancy of Intraductal Papillary Mucinous Neoplasms of the Pancreas, Mucopolysaccharides in the Mucin of Pancreatic Mucus is Useful? Yoshikazu Toyoki, Kenichi Hakamada [Background/Aim] Intraductal papillary-mucinous neoplasmas (IPMNs) of the pancreas has a wide range of malignant potentials in which the preoperative accurate diagnosis of carcinoma still remains challenging. The aim of this study is to determine predictive indicators for malignant lesion in IPMNs. We focused on mucopolysaccharides in mucin of pancreatic juice from IPMNs. [Patients]Medical records of 44 patients with IPMNs operated on between 1990 and 2006 at our department were reviewed retrospectively. For examination of mucopolysaccharides in mucin, the specimen of IPMNs patients were stained by alcian-blue (pH 2.5 and 1.0) and PAS. The presence of acidic mucopolysaccharides in pancreatic mucin was determined by alcian-blue staining, the presence of neutral mucopolysaccharides in pancreatic mucin was determined by PAS staining. [Results] Seventeen patients had adenocarcinoma (including carcinoma in situ), 27 benign tumors. The five-year survival rate of the patients with benign tumors was 96.0%, and that of the patients with carcinoma was 73.7%. First, we examined risk factors for malignancy of these patients by preoperative imaging study (computed tomography, ultrasonography, pancreaticography and so on). By univariate analysis, Diameters of the main pancreatic duct and the presence of mural nodules were associated with malignancy (p=0.0009, p=0.004). However, there were no predictive factors for malignant tumors by multivariate analysis. Second, we determined the sugar chain in pancreatic mucin for examination of biological function by clinicopathological study, the patients of positive staining of alcian-blue (pH 2.5 and 1.0) were more frequent malignancy than that of negative staining (p=0.017, p=0.0041). The patients of positive staining of PAS were more frequent benign tumors than that of negative staining (p=0.044). [Conclusion]Our data suggested that it was difficult to diagnose as the malignancy of IPMNs by preoperative imaging study. We focused on sugar chains in mucin of pancreatic juice from IPMNs. The presence of acidic mucopolysaccharides was associated with malignancy. We plan to analysis of the acidic mucopolysaccharides in pancreatic juice from preoperative patients with IPMNs.
T1371 Intraductal Papillary Mucinous Neoplasms and Extrapancreatic Malignancies: Is it a Real Association or Just a Coincidence? Kazumichi Kawakubo, Minoru Tada, Suguru Mizuno, Hiroshi Yagioka, Takashi Sasaki, Hirofumi Kogure, Yousuke Nakai, Kenji Hirano, Naoki Sasahira, Hiroyuki Isayama, Kazuhiko Koike Background & Aims: Intraductal papillary mucinous neoplasms (IPMN) of the pancreas has been reported to be associated with extrapancreatic malignancies, but there have been no prospective studies evaluating the incidence of extrapancreatic cancers in patients with IPMN. In this study, we prospectively examined the frequency of developing extrapancreatic cancers after diagnosis of IPMN. Methods: All patients with IPMN diagnosed at Tokyo University Hospital from 1995 to 2008 were identified. After excluding patients with preexisting and concomitant extrapancreatic malignancies, a total of 777 patients with IPMN were prospectively followed up for 3.5 years on average. We compared the incidence of observed each extrapancreatic malignancies with the expected incidence of age-gendermatched general Japanese population by using the Vital statistics of Japan. Results: Extrapancreatic cancers developed in 38 of 777 patients with IPMN during the period (1.38% per year). The most common malignancies were hepatocellular (n = 7), colorectal (n = 6), prostate (n = 4), gastric (n = 4), and lung cancers (n = 4). The calculated standardized incidence rate of each malignancies were as follows (95% Confidence interval); hepatocellular 2.90 (0.75-5.05), colorectal 1.07 (0.21-1.94), prostate 1.08 (0.02-2.13), gastric 0.56 (0.011.11), and lung cancers 084 (0.02-1.66). During the same period, pancreatic cancer developed in 13 patients, with a standardized incidence rate of 9.57 (4.37-14.77). Conclusions: Our results shows that, contrary to several recent reports, the incidence of extrapancreatic malignancies in patients with IPMN is equal to that in general population, whereas the incidence of pancreatic cancer is high. Further prospective studies are needed to elucidate the clinical course of the patients with IPMN.
T1374 EZH2 Knock Down by Lentiviral shRNA Inhibits Pancreatic Ductal AdenoCarcinoma Cell Proliferation In Vitro and Tumor Growth In Vivo Ramesh B. Batchu, Aamer Qazi, Shelly Seward, Masood A. Shammas, Sreedhar Chamala, Assaad Semaan, Christopher P. Steffes, Donald W. Weaver Background: Enhancer of zeste homologue 2 (EzH2) is a component of chromatin modification protein complex with methyl transferase activity. EzH2 is up regulated in various cancers and has been proposed to be a marker of aggressive phenotype. High levels of EzH2 have been observed in pancreatic ductal adeno-carcinoma (PDAC), however its role in disease progression is not well understood. Diseases, for which an abnormal gene function can be attributed as a cause, can be potentially treatable using gene silencing with short interfering RNA (siRNA). In proliferating cells such as cancer cells, siRNA activity is short lived. To get around this problem, lentiviral vector-based systems for the introduction and stable expression of siRNA in target cells have been developed. In this system, siRNA cassette is driven by U6 RNA polymerase III promoter that express sense and antisense strands separated by short hairpin RNAs (shRNAs) that are cleaved by the Dicer to generate continuous supply of siRNA In Vivo. Here we investigated potential role of EzH2 in PDAC by lentiviral shRNA mediated knock down of EzH2 to understand its contribution in the tumor progression. We further evaluated the ability of EzH2 depleted PDAC cells to form tumors in CB17/ICrSCID mice In Vivo. Methods: PANC-1 and MiaPaca-2 cell lines were transduced with lentiviral EzH2 shRNA (sense sequence of the shRNA in the vector: 5' CCG GCC CAA CAT AGA TGG ACC AAA TCT CGA GAT TTG GTC CAT CTA TGT TGG GTT TTT G 3). Standard protocols were followed for western blot analysis of EzH2 levels after lentiviral transduction. Triplicate growth curves were generated with cell counting kit-8 (CCK-8, Dojindo scientific). Approximately million PANC-1 cells transduced with lentiviral EzH2 shRNA were injected subcutaneously into CB17/ICr-SCID mice for tumor xenograft studies. Results: Significant down-modulation of EzH2 was observed in MiaPaca-2 cells and PANC-1 cells after lentiviral transduction. Further, we observed reduction in the cell proliferation of both PANC-1 and MiaPaca-2 cell lines in response to EzH2 knock down by lentiviral shRNA transduction. The ability of PANC-1 cells to produce palpable tumors after EzH2 knockdown in CB17/ ICr-SCID mice was reduced by over 80% compared to control cells indicating not only that EzH2 is needed for the growth of PDAC In Vivo but also the efficiency of lentiviral shRNA particles. Conclusions: The results indicate that the lentiviral shRNA mediated EzH2 epigenetic silencing may be a potential therapeutic strategy for PDAC.
T1372 Indication for Resection of Pancreatic Branch Duct Intraductal Papillary Mucinous Neoplasms: Reconsideration on the Basis of Analysis of Resected and Conservatively Followed up Cases Hiroko Nebiki, Koichi Taira, Shiba Masatugu, Reiko Ashida, Tetsuo Arakawa Objective: The International Consensus Guidelines for Management of Intraductal Papillary Mucinous Neoplasms of the Pancreas state that appearance of symptoms attributable to the cyst, presence of intramural nodules, cyst size > 30 mm, dilatation of the main pancreatic duct (>6mm) would be indications for resection of branch duct IPMNs. They also state that further study is needed to determine if all branch duct IPMNs > 30 mm in size should be resected immediately. No clear statement is made with regard to the size of mural nodules. In our hospital, resection is indicated for branch duct IPMNs if there is a mural nodule of at least 5 mm in size, if the main pancreatic duct diameter is at least 6 mm, or if symptoms are present. A wait-and-see approach is taken for all other cases of branch duct IPMNs. We reconsidered the surgical indications for branch duct IPMNs on the basis of an analysis of resected cases and conservatively followed up cases. Patients and Methods: Between January 1996 and September 2009, we encountered 109 patients with branch duct IPMNs, consisting of 24 who underwent resection and 85 who were managed conservatively. The 24 resected cases consisted of 11 cases of adenoma and 13 of cancer. Analysis of resected cases: Mural nodules of >5 mm were found in 13 cancer cases and 4 adenoma cases, while nodules of >10 mm were found in 9 patients, all of whom had cancer. A main pancreatic duct diameter of >6 mm was seen in 4 patients, all of whom had cancer. Cyst size exceeded 30 mm in 21 patients, 12 of whom had cancer, and it exceeded 50 mm in 8 patients, 7 of whom had cancer. A mural nodule size of at least 5 mm but less than 10 mm was observed in 8 patients, and all 3 of those patients who had a cyst size of at least 5 cm had cancer. Analysis of dfollowed-up cases: There were 6 patients with no mural nodules despite having a cyst with a size of at least 30 mm and who were managed conservatively. These included 3 in whom there was almost no enlargement and also no development of nodules. One patient was monitored for 7 years and underwent resection due to development of a mural nodule,
AGA Abstracts
T1375 Expression of Mir-101 Inhibits Cell Growth and Proliferation by Down Regulation of EZH2 in PANC-1 Cells Both In Vitro and In Vivo Ramesh B. Batchu, Aamer Qazi, Assaad Semaan, Sreedhar Chamala, Shelly Seward, Christopher P. Steffes, Masood A. Shammas, Donald W. Weaver Objectives: MicroRNAs (miRNA) are 22-nucleotide highly conserved non-coding RNA molecules that enhance mRNA degradation and translational repression of target genes. Although identified relatively recently, miRNAs have been recognized as major players in gene expression. Emerging evidences strongly suggest a crucial role played by miRNA-mRNA interaction
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