Tokio Wakabayashi

Clinical study of chronic pancreatitis with focal irregular narrowing of the main pancreatic duct and mass formation: comparison with chronic pancreatitis showing diffuse irregular narrowing of the main pancreatic duct.

Introduction Main pancreatic duct (MPD)-narrowed chronic pancreatitis (CP) may be an autoimmune abnormality. It also has been called autoimmune pancreatitis and sclerosing pancreatitis. It is unclear whether cases with focal pancreatographic changes are part of the same clinical entity as cases with diffuse MPD changes. Aim and Methodology We reviewed seven cases of chronic pancreatitis (CP) with focal narrowing of the main pancreatic duct (MPD), evidenced by endoscopic retrograde cholangiopancreatography (ERCP), and swelling of one or two segments of the pancreas, evidenced by ultrasonography (US) /computed tomography (CT), and indicated the clinicopathologic features of focal-type MPD-narrowed CP. Results The patient group comprised six men and one woman, and their age range was 28–75 years, with a mean of 63.7 years. Affected sites were in the head in two patients, the body in one patient, the tail in one patient, and the body and tail in three patients; ERP showed narrowing in six patients and obstruction in one. Stricture of the lower portion of the common bile duct (CBD) that caused obstructive jaundice was shown by ERC in two cases in which the pancreas head was affected. In all six patients, a dynamic study by CT or MRI homogeneously showed delayed enhancement of involved segments of the pancreas. Serum levels of pancreatic enzyme were elevated in five patients, but only one subject had pancreatitis-like epigastric pain. Serological evidence suggestive of autoimmune abnormality was detected in only three patients with hypergammaglobulinemia (≥2.0 g/dL) or positive titers of antinuclear antibody (ANA; ≥80). Histological assessment was available for five patients, who characteristically had dense lymphocytic or plasmocytic infiltration with severe fibrosis that caused luminal narrowing. The clinical, serologic, and histologic findings as described above were comparable to those for 12 CP patients with diffuse narrowing of the MPD, diagnosed during the same period. Surgical resection was performed in 5 patients, in 2 of whom a similar inflammatory process recurred in the remnant head of the pancreas, whereas pancreatitis no longer developed in the other 3 patients. One patient was initially treated with steroids, with clinical remission, although there was neither hypergammaglobulinemia nor positive ANA. Conclusion These results indicate that CP with focal narrowing of the MPD is part of the same clinical spectrum as CP with diffuse narrowing of the MPD, and whether the distribution is diffuse or focal seems to be related to the stage or the extent of the disease. It is therefore important to recognize the possible existence of this focal variant to avoid unnecessary surgery.

Identification of K‐ras Oncogene Mutations in the Pure Pancreatic Juice of Patients with Ductal Pancreatic Cancers

Pancreatic cancer is detected on the basis of morphological changes delineated by means of various image‐diagnostic methods. However, differentiation between chronic pancreatitis and pancreatic cancer, especially at the early stage, is not always simple when based upon the morphological changes alone. Therefore, we attempted to elucidate K‐ras mutations in the sediment of pure pancreatic juice (PPJ) containing exfoliated ductal pancreatic cancer cells. PPJ was collected endoscopically from 20 patients with pancreatic cancer (PC) and 18 patients with chronic pancreatitis (CP). Polymerase chain reaction and allele specific oligonucleotide dot blot hybridization for K‐ras mutations were performed with the DNA extracted from these samples. A K‐ras mutation at codon 12 was identified in the PPJ of 11/20 (55%) of the patients with PC. On the other hand, the same mutation was not identified in the PPJ of any patient with CP. Moreover, K‐ras mutations at codons 13 and 61 were not recognized in the PPJ of any patient with either PC or CP. These findings suggested that the presence of a K‐ras mutation at codon 12 in PPJ would be useful in confirming the diagnosis of PC.

Detection of K-ras point mutations at codon 12 in pure pancreatic juice for the diagnosis of pancreatic cancer by PCR-RFLP analysis

The present study was undertaken to detect K-ras point mutations at codon 12 in pure pancreatic juice (PPJ) for the diagnosis of pancreatic cancer (PC) using the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. PPJ was collected through a cannula under a duodenal fiberscope from 26 patients with PC and 32 patients with chronic pancreatitis (CP). DNA was extracted from PPJ and was used as the template for PCR. Analysis of PPJ by PCR-RFLP with Bst NI revealed that the incidence of K-ras point mutations at codon 12 was 81% (21/26) in patients with PC and 6% (2/32) in those with CP. With reference to the location of PC, the incidence of K-ras mutations was 79% (11/14) in the head, 86% (6/7) in the body, and 80% (4/5) in the tail of the pancreas. The incidence of K-ras mutants was 50% (1/2) in tumor size 1 (TS1; ≤2.0 cm in size), 71% (5/7) in TS2 (2.1 to ≤4.0 cm), 89% (8/9) in TS3 (4.1 to ≤6.0 cm), and 88% (7/8) in TS4 (>6.1 cm). These results suggested that analysis of K-ras point mutations at codon 12 in PPJ using the PCR-RFLP method is a promising new genetic test for the diagnosis of PC.

Appropriate steroid therapy for autoimmune pancreatitis based on long-term outcome

Objective. Because autoimmune pancreatitis (AIP) responds well to corticosteroids, many AIP patients are given this treatment. However, there is no consensus on the indications, dose, or duration of steroid treatment. The aim of this study was to establish the most appropriate steroid therapy regimen. Material and methods. We retrospectively reviewed morphological and serological improvement after steroid therapy and long-term outcome including relapse in 41 AIP patients who were given steroid therapy and were prospectively followed-up for more than 1 year. Results. All patients responded to steroid therapy, which was given because of bile duct stenosis secondary to sclerosing cholangitis in 34 AIP patients. Pancreatic enlargement normalized within one month; however, 13 patients had incomplete resolution of pancreatic duct narrowing, and 14 patients had incomplete resolution of bile duct stenosis. There was no correlation between the degree of morphological improvement and the initial prednisolone dose (30 mg and 40 mg/day). In 58% of 19 patients, serum IgG4 elevation failed to normalize. Glucose intolerance improved in 38% of the 21 patients with diabetes mellitus. Nine patients who had complete morphological and serological resolution, stopped their medication, and none have relapsed. Thirty-two patients continued maintenance therapy, and 4 of these patients suffered relapse. Conclusions. The indications for steroid therapy in AIP patients include bile duct stenosis caused by sclerosing cholangitis and other systemic diseases, such as retroperitoneal fibrosis and diabetes mellitus. We recommend that oral prednisolone be used at an initial dose of 30 mg/day; maintenance therapy is required in cases without complete morphological and serological resolution.

Clinical management of intraductal papillary mucinous tumors of the pancreas based on imaging findings.

The aim of this study was to assess the imaging findings of pathologically proven intraductal papillary-mucinous tumors of the pancreas and the natural history of follow-up cases, and to optimize the therapeutic management of patients with these tumors according to their imaging findings. All nine patients with main duct type tumors were histologically diagnosed as having adenocarcinoma or adenoma, with no hyperplastic lesion. The images failed to discriminate between the two histologic types. In 26 patients with branch duct type tumors, all but one with intraductal mural nodules or tumors of ≧30 mm had adenocarcinoma or adenoma, regardless of the caliber of the main duct. Of the nine patients with tumors < 30 mm and no mural nodules, three had adenoma, and six had hyperplasia. All of four patients had hyperplasia, with the additional caliber of the main duct being < 6 mm. In a series of 23 cases in which the patient was followed-up, no apparent progression was found in 17 patients who had no mural nodules and tumors of < 30 mm. Given these results, patients with main duct type tumors, and those with branch duct type tumors showing mural nodules or a tumor diameter of ≧30 mm, are at high risk of developing neoplasms, including adenocarcinoma, for which surgical resection should be considered, whereas those patients with tumors < 30 mm and no mural nodules can be followed.

Chronic pancreatitis with diffuse irregular narrowing of the main pancreatic duct.

In chronic pancreatitis (CP), dilatation with irregular lining of the wall of the main pancreatic duct (MPD) and its late ral side branche s is commonly found on endoscopic re trograde cholangiopanc reatography (ERCP) and is recognized as one of the clinical criteria for the diagnosis of this disease by ERCP (1± 3). This re ̄ ects the histologic change s of the gland such as increased interstitial connective tissue and irregular loss of acini. However, there are also some cases of CP that show no dilatation of the pancreatic duct, even in the advanced stage. Recently, Toki et al (4) reported four cases of CP showing diffuse irregular narrowing of the MPD on ERP different from the usually observed irregular dilatation. These CP cases were characte ristic in their MPD ® ndings: marked stenosis and irregularity of the wall without prestenotic dilatation throughout the gland. However, the clinical features of this special form of pancreatitis have yet to be evaluated in detail, and in particular little is known of its long-te rm prognosis. Here, we report three patients with CP showing diffuse irregular narrowing of the MPD on ERP, in two of whom change s in the ERP ® ndings could be followe d. In addition, we review cases of pancreatitis in the lite rature , in which pancreatograms with similar ® ndings were obtained.

Autoimmune pancreatitis in young patients.

Goals To examine whether there is a difference in the autoimmune pancreatitis (AIP) seen in young and elderly patients. Background AIP has a preponderance for elderly males, although the reason is unknown. Study A total of 64 patients with AIP were divided into a young (<40 y old) group and a middle-aged or elderly group (≥40 y old) according to the age at diagnosis. The clinical findings of each group were compared. Results The young group consisted of 6 patients (3 men, 3 women) with a mean age of 33.0 (range, 28 to 37) years. In the middle-aged or elderly group, there were 58 patients with a mean age of 66.4 (range, 46 to 83) years; males predominated (79%). Abdominal pain as the presenting symptom was significantly more frequent in the young group than in the middle-aged or elderly group (100% vs. 43%, P<0.05). Obstructive jaundice was detected in only 17% (1/6) of patients in the young group compared with 59% (34/58) of patients in the middle-aged or elderly group. Serum amylase elevations were detected more frequently in the young group than in the middle-aged or elderly group (83% vs. 40%, P<0.05). One young patient also had ulcerative colitis. Conclusions Although rare in Japan, young patients with AIP show different clinical features from middle-aged or elderly patients with AIP; young patients are more likely to have abdominal pain and serum amylase elevations.

Expression of mesothelin mRNA in pure pancreatic juice from patients with pancreatic carcinoma, intraductal papillary mucinous neoplasm of the pancreas, and chronic pancreatitis.

Objectives: In the gene expression analysis of pancreatic carcinoma (PCa) using serial analysis of gene expression (SAGE) according to Ryu et al, the tag for the mesothelin mRNA transcript was present in 7 of 8 SAGE libraries derived from PCa but not in the 2 SAGE libraries derived from normal pancreatic duct epithelial cells. Mesothelin mRNA expression was confirmed with in situ hybridization in all 4 resected primary PCa tumors and with RT-PCR in 18 of 20 PCa cell lines, whereas mesothelin protein expression was confirmed with immunohistochemistry in all 60 resected primary PCa tissues by Argani et al. We evaluated mesothelin mRNA expression in pure pancreatic juice (PPJ) obtained from patients with PCa, chronic pancreatitis (CP), and intraductal papillary mucinous neoplasm (IPMN) of the pancreas. Methods: We evaluated mesothelin mRNA expression in the PPJ obtained from 21 patients with PCa, 22 with CP, and 11 with IPMN with reverse transcriptase PCR (RT-PCR). The PCR products were analyzed with agarose gel electrophoresis. DNase I treatment before RT-PCR and direct sequencing of the RT-PCR bands were performed for the analysis of the RT-PCR bands. Results: Two products, of 308 and 226 bp, were obtained with RT-PCR, and the 308-bp RT-PCR product was confirmed as being that derived from the genomic DNA by direct DNA sequencing. Mesothelin mRNA expression was discovered using RT-PCR in 11 (52%) of 21 patients with PCa, 5 (45%) of 11 with IPMN, and 3 (14%) of 22 with CP. Fishers exact test revealed significant differences between PCa and CP for mesothelin mRNA (P < 0.01). Moreover, the RT-PCR product (226 bp) of mesothelin mRNA in the PPJ samples with PCa was generally stronger than that in the PPJ samples with IPMN. Conclusion: Expression of mesothelin mRNA in PPJ was not strictly specific to PCa and was apt to be stronger in PCa than in IPMN. Quantitative detection of mesothelin mRNA in PPJ may have potential diagnostic implications for pancreatic tumors.

Immunohistochemical study of p53, c-erbB-2, and PCNA in Barrett's esophagus with dysplasia and adenocarcinoma arising from experimental acid or alkaline reflux model

Purpose. An immunohistochemical study of p53, c-erbB-2, and proliferating cell nuclear antigen (PCNA) in Barretts esophagus with dysplasia and adenocarcinoma, arising from experimental acid or alkaline reflux, was performed in dogs. Methods. Cardiectomy was performed in group A (n = 26) as an acid reflux model, and total gastrectomy was performed in group B (n = 24) as an alkaline reflux model. After surgery, the esophageal mucosa was observed and biopsied endoscopically every 3 months over a period of 6 years. Immunohistochemical staining of p53, c-erbB-2, and PCNA was performed, using biopsied specimens. Results. In group A, Barretts esophagus developed in 14 of the 26 dogs. Low-grade dysplasia occurred in 5 of the 26 dogs, and in 1 of these 5 dogs, it developed into high-grade dysplasia. In this animal, adenocarcinoma arose 63 months after the operation. In group B, Barretts esophagus developed in 10 of the 24 dogs. Low-grade dysplasia was observed in 4 of the 24 dogs. In 1 of these 4 dogs, the dysplasia became high-grade and adenocarcinoma occurred 66 months after the operation. In group A, PCNA was positive in adenocarcinoma; the PCNA labeling index (LI) was 58. c-erbB-2 and p53 were negative in all animals in group A. In group B, PCNA was positive in Barretts esophagus with high-grade dysplasia and adenocarcinoma; the PCNA LI was 77. p53 was positive in adenocarcinoma. c-erbB-2 was negative in adenocarcinoma. Conclusions. The results of this study provided evidence of the dysplasia-carcinoma sequence arising from alkaline reflux, as well as from acid reflux. To the best of our knowledge, this is the first report of the use of an alkaline reflux model and a 6-year study using dogs to observe the course of Barretts esophagus.

Diagnostic significance of cancer-associated carbohydrate antigen (CA19-9) concentrations in pancreatic juice: analysis in pure pancreatic juice collected by endoscopic aspiration and immunohistochemical study in chronic pancreatitis.

This study evaluated the diagnostic significance of concentrations of the cancer-associated carbohydrate antigen CA 19–9 in pure pancreatic juice (PPJ) collected by endoscopic cannulation. We also attempted to elucidate the features and source of the increased CA 19–9 concentration found in the pancreatic juice of patients with chronic pancreatitis (CP) by means of immunohistochemical staining. The mean output as well as the mean concentration of CA 19–9 in each of the four fractions collected was highest in patients with pancreatic cancer (PC) and also was elevated significantly in patients with CP compared with controls. However, CA 19–9 concentrations were not elevated in patients with cholecystolithiasis. When the cutoff value was set as the mean concentration + 2SD of the controls, significantly elevated concentrations of CA 19–9 were found in the third fraction (secretory phase) in 90% of the patients with PC and 66% of the patients with CP. Immunohistochemical staining revealed that CA 19–9 was expressed more widely in the ductal cells of CP tissues than in those of normal pancreatic (NP) tissues, with CP tissue showing more CA 19–9-positive ductal cells per area than NP tissues. In NP tissue, CA 19–9 was localized to the apical surface and supranuclear regions (apical type) in all the ductal cells stained by the antigen, while ∼50% of cases with CP exhibited a cytoplasmic pattern showing a loss of polarity of the antigen expression. Moreover, this cellular localization pattern was more pronounced in the small ducts that had proliferated and aggregated following the destruction of lobules in CP. These results indicate that although increased concentrations of CA 19–9 in PPJ have no cancer specificity, measurement of CA 19–9 in PPJ can be used as a sensitive marker for some pancreatic disorders, and higher CA 19–9 concentrations in the pancreatic juice of patients with CP may reflect the strong expression of CA 19–9 in the proliferating small ducts associated with CP.