Pancreatic duct lavage cytology with the cell block method for discriminating benign and malignant branch-duct type intraductal papillary mucinous neoplasms.

BACKGROUND: Differentiation between benign and malignant branch-duct type intraductal papillary mucinous neoplasms (IPMNs) remains challenging. OBJECTIVE: To examine the usefulness of pancreatic duct lavage cytology with cell block method for discriminating benign and malignant branch-duct type IPMNs. PATIENTS AND METHODS: Between December 2007 and April 2011, patients with branch-duct type IPMNs having mural nodules on EUS were examined by pancreatic duct lavage cytology by using the cell block method. Cell block sections underwent hematoxylin and eosin staining and mucin immunostainings (MUCs 1, 2, 5AC, and 6). DESIGN: Single-center, prospective study. SETTING: Academic medical center. MAIN OUTCOME MEASUREMENTS: The sensitivity and specificity of cytology were assessed. The agreement between cytological and histological results for MUC was also examined. RESULTS: Cytology with this method was investigated in 44 patients. Cell block diagnosis was cancer positive (class V or IV) in 11 patients and negative (classes I, II, III, and noninformative) in 33. The sensitivity, specificity, and positive and negative predictive values of this method were 92%, 100%, 100%, and 97%, respectively. The cytological and histological results of MUCs 1, 2, 5AC, and 6 agreed in 88% (15/17), 94% (16/17), 88% (15/17), and 100% (17/17), respectively. LIMITATIONS: Single center and small number of patients. CONCLUSIONS: Pancreatic duct lavage cytology with the cell block method may be useful to differentiate between benign and malignant IPMNs preoperatively and as well as to determine their mucin type.

Malignant lymphoma with diffuse cardiac involvement detected by multiple imaging examinations: a case report.

INTRODUCTION: In malignant lymphoma, cardiac involvement, which usually forms pathologically focal and firm nodules in the cardiac walls, is considered to be a late manifestation of the disease. CASE PRESENTATION: We describe the case of a 71-year-old Asian Japanese woman whose first presentation of lymphoma was congestive heart failure. Multiple imaging examinations and laboratory findings led to a presumed diagnosis of a malignant lymphoma. A tissue diagnosis of the mediastinal mass could not be performed due to our patient's generally poor condition. Our patient received corticosteroid therapy, but died 42 days after her admission. An autopsy revealed lymphoid cells encircling her ventricular wall and infiltrating her endocardium. A histological examination confirmed the diagnosis of diffuse large B-cell lymphoma. CONCLUSION: Imaging examinations such as echocardiography, computed tomography with three-dimensional reconstruction, and gallium-67-citrate scintigraphy could clearly detect the diffuse cardiac involvement antemortem. A combination of these imaging techniques could provide a working diagnosis and allow empirical initiation of treatment in patients with poor general condition.

Amount of CD4+CD25+ regulatory T cells in autoimmune pancreatitis and pilonidal sinus.

OBJECTIVES: Infiltration of many IgG4-positive plasma cells (G4-Ps) is seen in IgG4-related diseases and in several "non-IgG4-related diseases," such as pilonidal sinus (PS) as well. The involvement of CD4+CD25+ regulatory T cells (CD4CD25 Tregs) in IgG4-related diseases has been reported. To see whether CD4+CD25+ Tregs are involved in autoimmune pancreatitis (AIP)/non-IgG4-related diseases with many G4-Ps, we investigated the amount of G4-Ps and CD4+CD25+ Tregs histologically in AIP/PS. METHODS: Four AIP and 10 PS were immunostained with IgG4/Foxp3, a specific marker for CD4+CD25+ Tregs. Double immunohistochemistry and dual fluorescent immunohistochemistry were conducted to see the amount of CD4+CD25+ Tregs. RESULTS: All AIP and 30% of PS showed abundant G4-Ps. G4-Ps infiltrated diffusely for all AIPs and in a patchy pattern for PS at the abscess/granulation foci. Foxp3 immunostaining/double immunohistochemistry showed moderate to abundant CD4+CD25+ Tregs in AIP and abscess of PS, but few to moderate in granulation of PS. Dual fluorescent immunohistochemistry also showed many CD4+CD25+ Tregs in AIP. CONCLUSIONS: Many CD4+CD25+ Tregs were seen in AIP lesions, abscess of PS, but not in granulation of PS, suggesting that the amount of CD4+CD25+ Tregs sometimes do not synchronize with that of G4-Ps and might relate to the inflammatory activity of both AIP and PS.

Pancreatic ductal adenocarcinoma derived from IPMN and pancreatic ductal adenocarcinoma concomitant with IPMN.

OBJECTIVES: Pancreatic ductal adenocarcinoma (PDAC) may derive from an intraductal papillary mucinous neoplasm (IPMN) of the pancreas or may develop in the pancreatic duct apart from IPMN. The purpose of this study was to define the clinicopathological features of these 2 entities and compare them with those of ordinary PDAC. METHODS: Of 765 patients who had surgical resection for IPMN, 122 were diagnosed as having PDAC derived from IPMN and 31 with PDAC concomitant with IPMN. In addition, 7605 patients with PDAC who were registered in the Japan Pancreas Society pancreatic cancer registry were compared with the above patients. RESULTS: Pancreatic ductal adenocarcinomas derived from IPMN and concomitant with IPMN were significantly smaller, less invasive, and less extensive than ordinary PDAC. The median survival of patients with the 2 conditions was significantly longer than for those with ordinary PDAC when compared overall or when limited to TS2 (2.0 cm < tumor size ≤ 4.0 cm) or TS3 (4.0 cm < tumor size ≤ 6.0 cm) cases. CONCLUSIONS: These findings suggest that PDAC concomitant with IPMN and PDAC derived from IPMN may have more favorable biological behaviors or be diagnosed earlier than ordinary PDAC.

Clinicopathological features and prognosis of mucinous cystic neoplasm with ovarian-type stroma: a multi-institutional study of the Japan pancreas society.

OBJECTIVE: The aim of this study was to elucidate the clinicopathological features and prognosis of mucinous cystic neoplasms (MCNs). MATERIALS AND METHODS: We performed a multi-institutional, retrospective study on a collected series of patients with MCN pathologically defined by ovarian-type stroma. Clinicopathological features and prognosis were investigated. RESULT: Mucinous cystic neoplasm was confirmed in 156 cases, including 129 adenomas (82.7%) and 21 noninvasive (13.4%) and 6 invasive carcinomas (3.9%). Patients with MCN were exclusively women (98.1%) with the mean age of 48.1 years. All but 1 MCN were in the pancreatic body/tail region with a mean size of 65.3 mm. Communication between the cyst and the pancreatic duct was found in 18.1%. The 3-, 5-, and 10-year survival rates were 97.6%, 96.6%, and 96.6%, respectively. A significant difference in the survival rates was observed between adenomas and carcinomas and between minimally invasive carcinomas and invasive carcinomas. Cyst diameter and presence of mural nodule were predictive of malignant MCN. CONCLUSIONS: Mucinous cystic neoplasm is a rare but distinctive pancreatic cystic neoplasm with a favorable overall prognosis. All MCNs should be resected to prevent malignant changes but can be observed for an appropriate time when the lesion is small without the presence of mural nodules.

Development and congenital anomalies of the pancreas.

Understanding how the pancreas develops is essential to understand the pathogenesis of congenital pancreatic anomalies. Recent studies have shown the advantages of investigating the development of frogs, mice, and chickens for understanding early embryonic development of the pancreas and congenital anomalies, such as choledochal cysts, anomalous pancreaticobiliary junction, annular pancreas, and pancreas divisum. These anomalies arise from failure of complete rotation and fusion during embryogenesis. There are many theories in the etiology of congenital anomalies of the pancreas. We review pancreas development in humans and other vertebrates. In addition, we attempt to clarify how developmental failure is related to congenital pancreatic anomalies.

Embryonal sarcoma of the liver in an adult mimicking complicated hepatic cyst: MRI findings.

Radiologically, embryonal sarcoma reveals a characteristic spectrum of both solid and cystic features. However, MRI is sometimes unable to reveal the solid components. Here, we describe a case in which intracystic hemorrhage revealed a solid mural nodule obscured with the cystic lesion. Knowledge of this feature is helpful when making a prospective diagnosis of this important, albeit rare, hepatic malignancy.

Unusual fusion between ventral and dorsal primordia causes anomalous pancreaticobiliary junction.

Anomalous pancreaticobiliary junction (APBJ) is a congenital anomaly in which the pancreatic duct joins the common bile duct proximal to the sphincter of Oddi. Anatomical and immunohistochemical examination of the pancreas with APBJ has rarely been performed. A 72-year-old woman with gallbladder cancer and APBJ died of respiratory failure. Macroscopic features of the pancreas were examined in detail. Immunohistochemistry using anti-pancreatic polypeptide (anti-PP) antibody was done to discriminate ventral and dorsal pancreas. Macroscopically the inferior part of the head of the pancreas was smaller than normal. The posterior surface of the head was obliquely grooved. Part of the pancreatic head protruded into the posterior side of the pancreatic head. A PP-rich region was located in the superioposterior position of the pancreas head. Considering the relationship between the ventral and dorsal pancreas, it was inferred that the ventral primordium could obliquely fuse with the dorsal primordium during embryological development. As a result, APBJ occurs through an abnormal fusion between ventral and dorsal primordia.

Does ampullary carcinoma arise from distended glands in the papilla of Vater?

BACKGROUND/PURPOSE: Glands near the surface of the papilla of Vater may become distended with mucus and become hyperplastic; that is, become distended. In this study, we tried to clarify carcinogenesis in these distended glands. METHODS: Twenty-nine pancreatoduodenectomized nontumorous duodenal papilla specimens from carcinoma of the pancreas and bile duct and 34 resected ampullary carcinoma specimens were studied histopathologically and immunohistochemically, using cytokeratins and mucin immunohistochemical features/phenotypes. RESULTS: Distended glands were found in 11 of the 29 pancreatoduodenectomized specimens. These glands were immunopositive for cytokeratin (CK) 7 and MUC-5AC Glycoprotein (MUC5AC), but not for CK20, while the intrapapillary portion was CK7-positive and CK20-negative, but mostly negative for MUC5AC. Immunopositivity for CK7, CK20, and MUC5AC was found in 25, 21, and 18 of the 34 specimens of ampullary carcinoma, respectively. In 23 of the 34 specimens, immunoreactivity for MUC5AC and that for CK7 was coincident, that is, when the former was immunopositive, so was the latter, and vice versa, while in 25 of the 34 specimens, immunoreactivity for MUC5AC was opposite to that for CK20. Among the 23 cases in which immunoreactivity for MUC5AC and CK7 was coincident, 10 were MUC5AC+, CK7+, CK20- and 7 were MUC5AC-, CK7-, CK20+, suggestive of disease arising from the pancreaticobiliary mucosa or the distended glands in the former and disease arising from the duodenal mucosa in the latter. In MUC5AC+ cases, other than the 10 cases of MUC5AC+, CK7+, CK20-, 6 were double-positive and 1 was double-negative for CK7 and CK20, and 1 was CK20-positive, and at least 1 case showing double-negativity for CK7 and CK20 was suggestive of disease arising from the distended glands. CONCLUSIONS: Although most ampullary carcinomas arise from the duodenal mucosa or intra-ampullary mucosa, both CK7-positive and MUC5AC-positive or only MUC5ACpositive ampullary carcinomas may arise from the distended glands.

Growth process of small pancreatic carcinoma: a case report with imaging observation for 22 months.

This report describes serial observations of the growth process of a small invasive ductal carcinoma (IDC) of the pancreas from imaging studies. Histopathological studies showed IDC with macroscopic retention cysts proximal to an intraductal papillary-mucinous adenoma with mild atypia of the branch duct type in the pancreatic body, with no relation between the two lesions. IDC was demonstrated as an extremely low-echoic mass resembling a cyst with an unclear margin on the initial endoscopic ultrasonography. We misinterpreted the low-echoic mass as a benign intraductal mucinous-papillary neoplasm (IPMN) based on findings of other imaging studies, and the patient was followed-up. The mass increased from 7 mm to 13 mm in diameter over 22 mo, and remained smaller than 10 mm in diameter for about 420 d. The tumor volume doubling time was 252 d. The Ki67 labeling index was 15.9%, similar to that described in previous reports. Hence, IDC may grow slowly while remaining small.

Intraductal carcinoma with complex fusion of tubular glands without macroscopic mucus in main pancreatic duct: dilemma in classification.

An 84-year-old man, who was being followed up after lobectomy for lung carcinoma, was referred for evaluation of a dilated main pancreatic duct (MPD) from the body to the tail. Endoscopic ultrasonography demonstrated a low-echo mass occupying the MPD from the body to the tail. Endoscopic retrograde pancreatography showed an occlusion of the MPD in the body, and brush cytology indicated malignant cells. Distal pancreatectomy was performed. Grossly, a white-yellow, irregular-shaped solid mass without macroscopic mucus filled the lumen of the MPD. Histologically, the mass consisted of a complex fusion of tubular glands with atypical nuclei, which did not have intracellular mucus and oncocytic cytoplasm. The tumor mass showed abrupt transition to the normal epithelium. Immunohistochemically the tumor cells were partially positive for mucin 1 (MUC1) and MUC6, and negative for MUC2, MUC5AC, and lipase. Unfortunately the patient died of brain metastasis from lung carcinoma 15 months later. A review of reported cases of intraductal tubular tumors of the pancreas showed that the present case involved characteristics and immunohistochemical staining pattern similar to those of intraductal tubular carcinoma, although it might not be described as a typical intraductal tubular carcinoma under the existing Japanese rules.

Distribution of intraductal lesions in small invasive ductal carcinoma of the pancreas.

AIMS: To investigate the distribution of intraductal lesions in small invasive ductal carcinoma (IDC) of the pancreas. METHODS: In 21 cases with IDCs microscopically < or = 20 mm in diameter, the intraductal lesions around a mass were studied histologically and mapped according to the pancreatic intraepithelial neoplasia (PanIN) classification. RESULTS: PanIN-3, PanIN-2, PanIN-1B and PanIN-1A were found in 17, 10, 20 and 21 of 21 cases, respectively, and were divided into lesions in adjacent and distal areas, respectively defined as within and beyond 10 mm from the mass as follows: 100% (17/17), 100% (10/10), 95.0% (19/20) and 90.5% (19/21) in the former, while 23.5% (4/17), 50.0% (5/10), 90.0% (18/20) and 95.2% (20/21) in the latter. PanIN-3 lesions were predominantly found in the area adjacent to the mass. In some cases, significant PanIN-3 appeared to show a consecutive geographic extension around the mass via the main pancreatic duct (MPD). The distance of PanIN-3 spread was within 25 (mean 10.5) mm from the mass edge. PanIN-2 lesions were found in the area adjacent to the mass and discontinuous with the mass or PanIN-3 lesions. PanIN-1B and PanIN-1A tended mainly to exist sporadically throughout the entire pancreas. In the MPD, PanIN-3 was found in 14 (82.4%) of 17 cases and in 36 (32.1%) of 112 lesions, which was most frequent in intraductal lesions. CONCLUSIONS: PanIN-3 lesions might be an intraductal extension of the main tumor. The resection margin of 25 mm, at least longer than 11 mm, from the mass edge will be necessary.

Invasive ductal adenocarcinoma of the pancreas may originate from the larger pancreatic duct: a study of 13 tumors less than 2 cm in diameter.

BACKGROUND/PURPOSE: We aimed to elucidate the origin/primary site of invasive ductal adenocarcinoma of the pancreas, based on the distribution of intraductal carcinoma components. These components were identified by a mural elastic fiber cuff. METHODS: Thirteen specimens from patients with invasive ductal adenocarcinoma (microscopically, less than 2 cm in diameter) of the pancreas were studied histopathologically. Variants of invasive ductal adenocarcinoma and intraductal papillary-mucinous carcinoma were excluded. RESULTS: Intraductal carcinoma components of invasive ductal adenocarcinoma were found in 12 of the specimens 13 (92%), and were observed within the tumor mass and/or on its boundary, or outside the tumor mass. Intraductal components were characterized by low papillary projections lacking a fibrovascular core, with/without surrounding tubular structures, or by irregular stratification and pleomorphism of the epithelial cells. Invasive components mostly showed a tubular pattern with desmoplasia. The distribution of the intraductal components in the 12 specimens was as follows: in 9 (75%), they were in both the main pancreatic duct and large branch ducts; and in 3, they were in the smaller branch ducts only. CONCLUSIONS: Invasive ductal adenocarcinomas of the pancreas may originate most frequently from the main pancreatic duct or larger branch ducts, while the smaller ducts are less often the site of cancer origin.

Isolated necrotizing arteritis (localized polyarteritis nodosa): examination of the histological process and disease entity based on the histological classification of stage and histological differences from polyarteritis nodosa.

INTRODUCTION: Although isolated necrotizing arteritis (INA) has been thought to be an isolated form of polyarteritis nodosa (PAN), a detailed histological comparison between INA and PAN has not been performed. Therefore, we examined the disease entity of INA based on the histological comparison of both diseases. In addition, a histological classification of INA, in which the histological process of INA is included, was described. METHODS: A histological study, including CD3, CD20, and CD68 immunostains, was performed in seven operated patients with INA. Five untreated patients with PAN were also examined. RESULTS: In INA, arteritis with fibrinoid necrosis occurred in small and medium-sized arteries in a single organ. INA was divided histologically into acute (five cases) and healed stage (two cases). Endothelial injury and medial degeneration, followed by fibrinoid necrosis, occurred in the acute stage, and regression of fibrinoid necrosis and fibrosis were present in the healed stage. Infiltration of predominant T lymphocytes and macrophages was also observed in the affected arteries. Histological comparison between INA and PAN led to the finding that the extension of fibrinoid necrosis in the entire arterial wall, which indicates severe wall destruction, intense proliferation of fibroblasts and aneurysm formation occurred in PAN alone. CONCLUSIONS: We demonstrated some histological differences between INA and PAN. Based on the histological similarities and differences between INA and PAN, it was concluded that INA shall be classified as a mildly wall destructive form of PAN-type arteritis located in a single organ.

Different patterns of p16INK4A and p53 protein expressions in intraductal papillary-mucinous neoplasms and pancreatic intraepithelial neoplasia.

OBJECTIVES: To examine aberrations and differences of cell cycle regulatory proteins between intraductal papillary-mucinous neoplasms (IPMNs) and pancreatic intraepithelial neoplasias (PanINs). METHODS: In total, 47 IPMN lesions and 42 PanIN lesions were obtained from 26 patients with IPMN and 16 patients who underwent pancreatic surgery for invasive pancreatic ductal cancer or other diseases. They were subjected to conventional hematoxylin-eosin staining and immunostaining for p16INK4A and p53. The percentages of immunohistochemical positivity or negativity were compared between IPMN and PanIN, in accordance with the same histological grade of atypia. The Ki-67 labeling index was also counted in each lesion. RESULTS: Either the loss of p16INK4A expression or the overexpression of p53 was much more frequently observed among PanIN-3 than among carcinoma in situ in IPMN (P = 0.046 and 0.008, respectively). The Ki-67 labeling index was correlated with the histological grades of both PanINs and IPMNs (P = 0.0001 and P = 0.0001, respectively). CONCLUSIONS: There are different immunohistochemical expression patterns of p16INK4A and p53 between IPMNs and PanINs. These may substantiate their different genetic progressions to invasive carcinoma.

Histopathological study of invasive ductal carcinoma (IDC) of the pancreas without associated cancerous occlusion of the main pancreatic duct.

BACKGROUND/PURPOSE: [corrected] Invasive ductal carcinoma (IDC) of the pancreas may be associated with cancerous occlusion of the main pancreatic duct (MPD) in its growth process, but at quite low a frequency; there are patients who do not develop this occlusion. METHODS: This study examined the histological features of surgical specimens from 8 patients with IDC without MPD occlusion, in comparison to 32 patients with IDC with this occlusion (controls). The pancreatic duct was identified by confirming the presence of mural elastic fibers on the wall of the pancreatic duct. Immunohistochemical staining was done with Ki-67 antibody. RESULTS: The frequency of IDC without MPD occlusion was very low (5.0% [2/40] patients at Kurume University and 3.1% [4/126] patients at Juntendo University). The number of intraductal carcinoma components was 1.5 +/- 1.1 per specimen in the IDCs without occlusion and 5.9 +/- 2.4 in the controls (P < 0.001). The Ki-67 labeling index was 18.0 +/- 11.7% in the IDCs without occlusion and 30.0 +/- 12.1% in the controls (P < 0.05). The number of intraductal carcinoma components and the Ki-67 labeling index were significantly lower in the IDCs without occlusion than in the controls. CONCLUSIONS: Our findings suggested that these two types of IDC could have different biological features.

Gallbladder carcinoma associated with pancreatobiliary reflux.

AIM: To detect the patients with and without pancreaticobiliary maljunction who had pancreatobiliary reflux with extremely high biliary amylase levels. METHODS: Ninety-six patients, who had diffuse thickness (>3 mm) of the gallbladder wall and were suspected of having a pancreaticobiliary maljunction on ultrasonography, were prospectively subjected to endoscopic retrograde cholangiopancreatography, and bile in the common bile duct was sampled. Among them, patients, who had extremely high biliary amylase levels (>10000 IU/L), underwent cholecystectomy, and the clinicopathological findings of those patients with and without pancreaticobiliary maljunction were examined. RESULTS: Seventeen patients had biliary amylase levels in the common bile duct above 10000 IU/L, including 11 with pancreaticobiliary maljunction and 6 without pancreaticobiliary maljunction. The occurrence of gallbladder carcinoma was 45.5% (5/11) in patients with pancreaticobiliary maljunction, and 50% (3/6) in those without pancreaticobiliary maljunction. CONCLUSION: Pancreatobiliary reflux with extremely high biliary amylase levels and associated gallbladder carcinoma could be identified in patients with and without pancreaticobiliary maljunction, and those patients might be detected by ultrasonography and bile sampling.