Mitsuro Kanda

Presence of somatic mutations in most early-stage pancreatic intraepithelial neoplasia

More information is needed about genetic factors that initiate development of pancreatic intraepithelial neoplasms-the most common precursors of pancreatic ductal adenocarcinoma. We show that more than 99% of the earliest-stage, lowest-grade, pancreatic intraepithelial neoplasm-1 lesions contain mutations in KRAS, p16/CDKN2A, GNAS, or BRAF. These findings could improve our understanding of the development and progression of these premalignant lesions.

Nutritional predictors of postoperative outcome in pancreatic cancer.

Nutritional status plays an important role in the incidence of postoperative complications and the prognosis of various tumours. The prognostic value of preoperative nutritional factors in patients with pancreatic cancer is not known.

Mutant GNAS detected in duodenal collections of secretin-stimulated pancreatic juice indicates the presence or emergence of pancreatic cysts

Objective Pancreatic cysts are commonly detected in patients undergoing pancreatic imaging. Better approaches are needed to characterise these lesions. In this study we evaluated the utility of detecting mutant DNA in secretin-stimulated pancreatic juice. Design Secretin-stimulated pancreatic juice was collected from the duodenum of 291 subjects enrolled in Cancer of the Pancreas Screening trials at five US academic medical centres. The study population included subjects with a familial predisposition to pancreatic cancer who underwent pancreatic screening, and disease controls with normal pancreata, chronic pancreatitis, sporadic intraductal papillary mucinous neoplasm (IPMN) or other neoplasms. Somatic GNAS mutations (reported prevalence ∼66% of IPMNs) were measured using digital high-resolution melt-curve analysis and pyrosequencing. Results GNAS mutations were detected in secretin-stimulated pancreatic juice samples of 50 of 78 familial and sporadic cases of IPMN(s) (64.1%), 15 of 33 (45.5%) with only diminutive cysts (<5 mm), but none of 57 disease controls. GNAS mutations were also detected in five of 123 screened subjects without a pancreatic cyst. Among 97 subjects who had serial pancreatic evaluations, GNAS mutations detected in baseline juice samples predicted subsequent emergence or increasing size of pancreatic cysts. Conclusion Duodenal collections of secretin-stimulated pancreatic juice from patients with IPMNs have a similar prevalence of mutant GNAS to primary IPMNs, indicating that these samples are an excellent source of mutant DNA from the pancreas. The detection of GNAS mutations before an IPMN is visible suggests that analysis of pancreatic juice has the potential to help in the risk stratification and surveillance of patients undergoing pancreatic screening.

Mutant TP53 in Duodenal Samples of Pancreatic Juice From Patients With Pancreatic Cancer or High-Grade Dysplasia

BACKGROUND & AIMS Imaging tests can identify patients with pancreatic neoplastic cysts but not microscopic dysplasia. We investigated whether mutant TP53 can be detected in duodenal samples of secretin-stimulated pancreatic juice, and whether this assay can be used to screen for high-grade dysplasia and invasive pancreatic cancer. METHODS We determined the prevalence of mutant TP53 in microdissected pancreatic intraepithelial neoplasias (PanINs), intraductal papillary mucinous neoplasms (IPMNs), and invasive adenocarcinomas. TP53 mutations were quantified by digital high-resolution melt-curve analysis and sequencing of secretin-stimulated pancreatic juice samples, collected from duodena of 180 subjects enrolled in Cancer of the Pancreas Screening trials; patients were enrolled because of familial and/or inherited predisposition to pancreatic cancer, or as controls. RESULTS TP53 mutations were identified in 9.1% of intermediate-grade IPMNs (2 of 22), 17.8% of PanIN-2 (8 of 45), 38.1% of high-grade IPMNs (8 of 21), 47.6% of PanIN-3 (10 of 21), and 75% of invasive pancreatic adenocarcinomas (15 of 20); no TP53 mutations were found in PanIN-1 lesions or low-grade IPMNs. TP53 mutations were detected in duodenal samples of pancreatic juice from 29 of 43 patients with pancreatic ductal adenocarcinoma (67.4% sensitivity; 95% confidence interval, 0.52-0.80) and 4 of 8 patients with high-grade lesions (PanIN-3 and high-grade IPMN). No TP53 mutations were identified in samples from 58 controls or 55 screened individuals without evidence of advanced lesions. CONCLUSIONS We detected mutant TP53 in secretin-stimulated pancreatic juice samples collected from duodena of patients with high-grade dysplasia or invasive pancreatic cancer. Tests for mutant TP53 might be developed to improve the diagnosis of and screening for pancreatic cancer and high-grade dysplasia. Clinical Trial numbers: NCT00438906 and NCT00714701.

Promoter hypermethylation of fibulin 1 gene is associated with tumor progression in hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) is one of the most common cancers world‐wide but the molecular mechanisms that underlie hepatocarcinogenesis are not fully determined. On the same surgical sample with HCC, we performed microarray‐based gene expression profiling and karyotype analysis using a single nucleotide polymorphism (SNP) array. In addition, quantitative real‐time reverse transcription polymerase chain reaction (PCR), methylation specific PCR (MSP) and immunohistochemical staining were conducted using specimens from 48 patients with HCC. Gene expression profiling showed the expression of fibulin 1 (FBLN1), located on 22q13, to be decreased in tumor tissue. Karyotype analysis revealed no loss of heterozygosity (LOH) since deletions were not detected in 22q, and one of the SNPs on 22q13 showed AB genotype in both cancerous tissue and in corresponding noncancerous tissue, indicating retention of heterozygosity. Quantitative real‐time PCR showed FBLN1 mRNA levels in cancerous tissues to be significantly decreased compared with that in corresponding noncancerous tissues. The immunohistochemical staining results were consistent with both gene expression profiling and quantitative PCR data. Twenty‐four out of 48 HCCs gave a positive result in MSP. Moreover, promoter hypermethylation of FBLN1 was significantly associated with advanced stage HCC, multiple tumors and increased tumor size. Our results indicated that FBLN1 is a novel candidate of tumor suppressor gene and that promoter hypermethylation of FBLN1 is associated with tumor progression in HCC.

Correlations of the expression of vascular endothelial growth factor B and its isoforms in hepatocellular carcinoma with clinico‐pathological parameters

The vascular endothelial growth factor (VEGF) is involved in the growth of cancer cells through angiogenesis. At present the role of VEGF‐B has not been clarified completely. We investigated correlations of the expression of VEGF‐B and its isoforms, VEGF‐B167 and VEGF‐B186, by alternative splicing in hepatocellular carcinoma (HCC) with the pathological findings and prognosis.

Prognostic impact of pancreatic margin status in the intraductal papillary mucinous neoplasms of the pancreas

BACKGROUND Intraductal papillary mucinous neoplasm (IPMN) of the pancreas often recurs after operative resection. The absolute risk and incidence of recurrence, however, especially in the remnant pancreas, is unknown. METHODS We reviewed our 18-year experience of 144 surgical cases of IPMNs and selected 103 cases of benign IPMN and carcinoma in situ (CIS) for analysis of the clinicopathologic features and long-term outcome of the recurrent disease, with particular emphasis on the status of the cut margins of the pancreas. RESULTS No patient with benign IPMN died within 5 years. Recurrences in the remnant pancreas were observed in 9 cases: 4 (4.9%) among the 81 cases of benign IPMNs and 5 (22.7%) among the 22 cases of CIS. All recurrences were considered as multicentric because none recurred at the true resection margin of the previous operative resection. The pancreatic transection margin was normal or hyperplastic in 64 patients, whereas adenoma was detected at the margin in 28 patients. The presence of adenoma had no influence on the outcome, and recurrence in the remnant pancreas was diagnosed in 5 (7.8%) of 64 adenoma-negative patients and 3 (10.7%) of 28 adenoma-positive patients. Furthermore, both overall survival and recurrence-free survival were similar between the 2 groups. CONCLUSION In benign IPMN and CIS, a favorable prognosis can be expected irrespective of the status of the pancreatic cut surface, although follow-up with adequate imaging studies is recommended for detection and resection of the recurrent disease.

Pattern of lymph node metastasis spread in pancreatic cancer.

Objectives: We aimed to clarify the detailed pattern of lymph node (LN) metastasis spread in patients with pancreatic cancer. Methods: This retrospective study enrolled 429 patients who underwent pancreatectomy with extended lymphadenectomy for pancreatic cancer. The prognostic implications of LN metastasis were evaluated, and the position, frequency, and association with other clinicopathologic factors were investigated. Results: Lymph node metastasis was confirmed pathologically in 289 patients (67.4%). The prognosis of patients with LN metastasis was significantly poorer than that of patients without LN metastasis (P < 0.001). Distant LN metastasis occurred frequently, regardless of the tumor site. Patients classified with T1 or T2 only had regional LN metastasis, whereas there was a high rate of distant LN metastasis, including the para-aortic LNs, in patients with T3 or higher-stage tumors. Para-aortic LN metastasis was significantly associated with arterial and perineural invasion (P = 0.006 and P < 0.001, respectively). Lymph node metastasis in the hepatic portal region was a strong predictor of para-aortic LN metastasis in pancreatic head cancer. Conclusions: Pancreatic cancer frequently metastasized to distant LNs via a complex pathway and developed into systemic disease. Aggressive multimodality therapy, including neoadjuvant therapy, is essential to improve the long-term survival of patients at substantial risk of distant LN metastasis.

Impact of operative blood loss on survival in invasive ductal adenocarcinoma of the pancreas.

Objectives: The aim of this study was to determine the prognostic factors and assess the impact of excessive operative blood loss (OBL) on survival after pancreatectomy for invasive ductal adenocarcinoma. Methods: From the retrospective analysis, 271 patients were eligible for evaluation. Overall survival was assessed to clarify the prognostic determinants, including patient characteristics, perioperative factors, and tumor characteristics. Results: The overall survival was significantly affected by the amount of OBL. The median survival times were 26.0, 15.3, and 8.7 months for OBL less than 1000, 1000 to 2000, and greater than 2000 mL, respectively (<1000 vs 1000-2000 mL, P = 0.019; 1000-2000 vs >2000 mL, P < 0.0001). Operative blood loss greater than 2000 mL remained an independent prognostic factor in multivariate analysis (P = 0.003; hazards ratio, 2.55). Operative blood loss of 2010 mL was found to be an appropriate cutoff level to predict early mortality within 6 months after resection (sensitivity, 0.660; specificity, 0.739). Male sex, year of resection, and plexus invasion were independently associated with OBL greater than 2000 mL. Conclusions: Excessive OBL was found to be a prognostic determinant of survival after surgery for pancreatic cancer. Operative blood loss can be used to stratify the risk for pancreatic cancer mortality. Successful curative resection with limited blood loss can contribute to improved survival.Abbreviations: OBL - operative blood loss, DGE - delayed gastric emptying, ROC - receiver operating characteristic, MST - median survival time, HR - hazards ratio

KRAS and Guanine Nucleotide-Binding Protein Mutations in Pancreatic Juice Collected From the Duodenum of Patients at High Risk for Neoplasia Undergoing Endoscopic Ultrasound

BACKGROUND & AIMS Pancreatic imaging can identify neoplastic cysts but not microscopic neoplasms. Mutation analysis of pancreatic fluid after secretin stimulation might identify microscopic neoplasias in the pancreatic duct system. We determined the prevalence of mutations in KRAS and guanine nucleotide-binding protein α-stimulating genes in pancreatic juice from subjects undergoing endoscopic ultrasound for suspected pancreatic intraepithelial neoplasia, intraductal papillary mucinous neoplasms, or pancreatic adenocarcinoma. METHODS Secretin-stimulated juice samples were collected from the duodenum of 272 subjects enrolled in Cancer of the Pancreas Screening studies; 194 subjects were screened because of a family history of, or genetic predisposition to, pancreatic cancer, and 78 subjects were evaluated for pancreatic cancer (n = 30) or other disorders (controls: pancreatic cysts, pancreatitis, or normal pancreata, n = 48). Mutations were detected by digital high-resolution melt-curve analysis and pyrosequencing. The number of replicates containing a mutation determined the mutation score. RESULTS KRAS mutations were detected in pancreatic juice from larger percentages of subjects with pancreatic cancer (73%) or undergoing cancer screening (50%) than controls (19%) (P = .0005). A greater proportion of patients with pancreatic cancer had at least 1 KRAS mutation detected 3 or more times (47%) than screened subjects (21%) or controls (6%, P = .002). Among screened subjects, mutations in KRAS (but not guanine nucleotide-binding protein α-stimulating) were found in similar percentages of patients with or without pancreatic cysts. However, a greater proportion of patients older than age 50 years had KRAS mutations (54.6%) than younger patients (36.3%) (P = .032); the older subjects also had more mutations in KRAS (P = .02). CONCLUSIONS Mutations in KRAS are detected in pancreatic juice from the duodenum of 73% of patients with pancreatic cancer, and 50% of asymptomatic individuals with a high risk for pancreatic cancer. However, KRAS mutations were detected in pancreatic juice from 19% of controls. Mutations detected in individuals without pancreatic abnormalities, based on imaging analyses, likely arise from small pancreatic intraepithelial neoplasia lesions. ClinicalTrials.gov no: NCT00438906 and NCT00714701.