Differential diagnosis of benign versus malignant nonfunctioning islet cell tumors of the pancreas: the roles of EUS and ERCP.

BACKGROUND: Differentiation between benign and malignant nonfunctioning islet cell tumors of the pancreas before surgery is often difficult. The roles of EUS and ERCP were evaluated in the differential diagnosis of these tumors. METHODS: Seven patients with histologically confirmed nonfunctioning islet cell tumors (4 benign, 3 malignant) underwent EUS and ERCP. OBSERVATIONS: EUS demonstrated a homogeneous hypoechoic mass or a hypoechoic mass with a regular central echogenic area in the 4 cases of benign tumor, and a hypoechoic mass with an irregular central echogenic area in all 3 cases of malignant tumor. The irregular central echogenic area corresponded to severe hemorrhage, necrosis, or fibrosis with hyalinosis (hyaline degeneration) on pathologic examination. ERCP demonstrated displacement or complete obstruction (because of ductal invasion) of the main pancreatic duct in 2 patients with malignant tumors and no abnormalities in the other 5 cases. CONCLUSIONS: In patients with nonfunctioning islet cell tumors, a hypoechoic mass with an irregular central echogenic area on EUS or complete obstruction of the main pancreatic duct on ERCP suggests malignancy.     

Endoscopic ultrasound characteristics of mucinous cystic neoplasms of the pancreas

OBJECTIVE: Mucinous cystic neoplasms of the pancreas have a more favorable prognosis than ductal adenocarcinoma. Management of a subgroup, intraductal papillary-mucinous neoplasms, is controversial. Endoscopic ultrasound (EUS) with fine-needle aspiration biopsy may emerge as the imaging modality of choice. There are few studies describing the EUS features of these tumors. METHODS: A total of 35 consecutive cases of cystic tumors of the pancreas with an established pathological diagnosis were analyzed for characteristic EUS features. RESULTS: Mucinous cystadenocarcinomas (n = 14) were more likely to be characterized by hypoechoic cystic/solid mass or complex cyst and were frequently associated with a dilated main pancreatic duct. Benign mucinous duct ectasia (n = 6) were characterized by a dilated main pancreatic duct in conjunction with hyperechoic thickening of the duct wall. The two cases of intraductal mucinous hyperplasia additionally showed a hypoechoic mass. Intraductal papillary carcinoma (n = 11) had features in common with mucinous cystadenocarcinoma but also had echogenic foci in the mass and intraductal hyperechoic lesions. The two cases of microcystic cystadenoma showed either a mixed hypoechoic solid/cystic mass or a complex cyst without the additional features seen in mucinous cystadenocarcinoma. CONCLUSIONS: EUS features seem to exist that may help to differentiate cystic neoplasms from adenocarcinoma of the pancreas and, thus, to establish the preoperative diagnosis of cystic tumors of the pancreas.     

Intraductal papillary-mucinous tumors of the pancreas: differential diagnosis between benign and malignant tumors by endoscopic ultrasonography

OBJECTIVES: Recently, intraductal papillary-mucinous tumor (IPMT) of the pancreas has increasingly been recognized. However, differential diagnosis between benign and malignant IPMT is often difficult using conventional imaging modalities. The purpose of this study was to retrospectively investigate the value of endoscopic ultrasonography (EUS) for differentiating malignant from benign IPMT. METHODS: A total of 51 patients with IPMT were preoperatively examined by EUS. The endosonograhic findings were compared with histopathological findings of the resected specimens. RESULTS: In main duct type IPMT, the diameter of the main pancreatic duct (MPD) was > or =10 mm in seven of the eight malignant tumors, compared with two of the seven benign tumors (p < 0.05). In branch duct type IPMT, three of the four large tumors (>40 mm) with irregular thick septa were malignant lesions. In both main duct type IPMT and branch duct IPMT, eight patients had large mural nodules (>10 mm); seven of the eight tumors were malignant and one of the eight tumors was benign. When the tumor was diagnosed as malignant according to above three findings, EUS was able to differentiate between malignant and benign IPMT with an accuracy of 86%. CONCLUSIONS: Main duct type tumors with > or =10 mm dilated MPD, branch duct type tumors (>40 mm) with irregular septa, and large mural nodules (>10 mm) strongly suggest malignancy on EUS. EUS would be a useful modality for differentiating between benign and malignant IPMT.     

Endoscopic approach for diagnosing autoimmune pancreatitis

It is of utmost importance to differentiate autoimmune pancreatitis (AIP) from pancreatic cancer (PC). Segmental AIP cases are sometimes difficult to differentiate from PC. On endoscopic retrograde cholangiopancreatography, long or skipped irregular narrowing of the main pancreatic duct (MPD), less upstream dilatation of the distal MPD, side branches derived from the narrowed portion of the MPD, absence of obstruction of the MPD, and stenosis of the intrahepatic bile duct suggest AIP rather than PC. Abundant infiltration of IgG4-positive plasma cells is frequently and rather specifically detected in the major duodenal papilla of AIP patients. IgG4-immunostaining of biopsy specimens obtained from the major duodenal papilla is useful for supporting a diagnosis of AIP with pancreatic head involvement. On endoscopic ultrasonography (EUS), hyperechoic spots in the hypoechoic mass and the duct-penetrating sign suggest AIP rather than PC. EUS and intraductal ultrasonography sometimes show wall thickening of the common bile duct even in the segment in which abnormalities are not clearly observed with cholangiography in AIP patients. EUS-guided fine needle aspiration, especially EUS-guided Tru-Cut biopsy, is useful to diagnose AIP, as well as to exclude PC.     

Role of endoscopic ultrasonography in the diagnosis and treatment of cystic tumors of the pancreas

Endoscopic ultrasound (EUS) allows high resolution imaging of the pancreas. EUS is a very useful technique for evaluating morphological features of a cystic tumors of the pancreas. These features include thick wall type, tumor protruding type, thick septal type, microcystic type, thin septal type and simple type. Malignant cystic lesions may present as a hypoechoic cystic/solid mass or as a complex cyst and are frequently associated with a dilated main pancreatic duct. There is some overlap between EUS appearances of non-neoplastic and neoplastic cystic pancreatic lesions. EUS guided FNA of cystic pancreatic lesions can play an important role in the differential diagnosis of these lesions and deciding about the need for surgery by evaluating cytology and tumor markers such as CEA in cyst fluid. There is some emerging data on EUS guided treatment of cystic pancreatic tumors by injection of alcohol.     

Preoperative diagnosis of insulinoma: low body mass index, young age, and female gender are associated with negative imaging by endoscopic ultrasound

OBJECTIVE: Endoscopic ultrasound (EUS) is a highly reliable procedure to localize insulinomas preoperatively. It has been considered to be important in planning surgical strategy, especially considering a minimal invasive approach. However, even under ideal conditions experienced examiners miss about 10-20% of insulinomas by EUS imaging. DESIGN AND METHODS: This retrospective study aimed to identify factors associated with negative EUS imaging. Twenty-nine consecutive patients (24 benign and 5 malignant) with sporadic pancreatic insulinomas confirmed by successful surgery and positive histopathology were included. All EUS examinations were performed by one single experienced examiner over a period of one decade. RESULTS: Three of the tumors were not detected by preoperative EUS as they were isoechoic to the surrounding healthy pancreatic tissue; 25 could be detected as hypoechoic lesions, (including all malignant tumors), and one lesion was hyperechoic. Low body mass index (P=0.053) and young age (P=0.037) were associated with negative EUS imaging. All patients with negative imaging were females. The position on the examiner's learning curve, the diameter and location of insulinoma, and endocrine parameters (insulin concentrations and insulin-glucose ratios in the prolonged fasting test) had no influence on the success of EUS imaging. CONCLUSIONS: Some insulinomas are missed by preoperative EUS imaging as they are completely isoechoic. A low body mass index, female gender, and young age might be risk factors for negative imaging.     

Intraductal growth of a nonfunctioning endocrine tumor of the pancreas

Intraductal growth of nonfunctioning endocrine tumors of the pancreas may be very rare, and our survey of literature shows only two cases have been described. We report a case of a 43-year-old man with a nonfunctioning endocrine tumor of the pancreas that uniquely grew within the lumen of the main pancreatic duct (MPD) without ductal involvement and completely obstructed the MPD. Endoscopic ultrasonography (EUS) and endoscopic retrograde cholangiopancreatography (ERCP) were very helpful to delineate the intraductal growth of the tumor and to determine the resection line of the pancreas. A nonfunctioning pancreatic endocrine tumor is important to consider on differential diagnoses when complete obstruction of the MPD is demonstrated on ERCP. It is speculated that the tumor originated from precursor cells of the pancreatic duct or islet cells adjacent to the MPD and slowly proliferated within the lumen of the MPD.     

Endoscopic ultrasound fine-needle aspiration characteristics of primary adenocarcinoma versus other malignant neoplasms of the pancreas

BACKGROUND:

Endoscopic ultrasound (EUS) with fine-needle aspiration (FNA) is often used to assist in the evaluation of pancreatic lesions and may help to diagnose benign versus malignant neoplasms. However, there is a paucity of literature regarding comparative EUS characteristics of various malignant pancreatic neoplasms (primary and metastatic).

OBJECTIVE:

To compare and characterize primary pancreatic adenocarcinoma versus other malignant neoplasms, hereafter referred to as nonprimary pancreatic adenocarcinoma (NPPA), diagnosed by EUS-guided FNA.

METHODS:

The present study was a retrospective analysis of a prospectively maintained database. The setting was a tertiary care, academic medical centre. Patients referred for suspected pancreatic neoplasms were evaluated. Based on EUS-FNA characteristics, primary pancreatic adenocarcinoma was differentiated from other malignant neoplasms. The subset of other neoplasms was defined as malignant lesions that were ‘NPPAs’ (ie, predominantly solid or solid/cystic based on EUS appearance and primary malignant lesions or metastatic lesions to the pancreas). Pancreatic masses that were benign cystic lesions (pseudocyst, simple cyst, serous cystadenoma) and focal inflammatory lesions (acute, chronic and autoimmune pancreatitis) were excluded.

RESULTS:

A total of 230 patients were evaluated using EUS-FNA for suspected pancreatic mass lesions. Thirty-eight patients were excluded because they were diagnosed with inflammatory lesions or had purely benign cysts. One hundred ninety-two patients had confirmed malignant pancreatic neoplasms (ie, pancreatic adenocarcinoma [n=144], NPPA [n=48]). When comparing adenocarcinoma with NPPA lesions, there was no significant difference in mean age (P=0.0675), sex (P=0.3595) or average lesion size (P=0.3801). On average, four FNA passes were necessary to establish a cytological diagnosis in both lesion subtypes (P=0.396). Adenocarcinomas were more likely to be located in the pancreatic head (P=0.0198), whereas masses in the tail were more likely to be NPPAs (P=0.0006). Adenocarcinomas were also more likely to exhibit vascular invasion (OR 4.37; P=0.0011), malignant lymphadenopathy (P=0.0006), pancreatic duct dilation (OR 2.4; P=0.022) and common bile duct dilation (OR 2.87; P=0.039).

CONCLUSIONS:

Adenocarcinoma was more likely to be present in the head of the pancreas, have lymph node and vascular involvement, as well as evidence of pancreatic duct and common bile duct obstruction. Of all malignant pancreatic lesions analyzed by EUS-FNA, 25% were NPPA, suggesting that FNA is crucial in establishing a diagnosis and may be helpful in preoperative planning.     

Endoluminal ultrasonography for pancreatic diseases.

Endoluminal ultrasonography was performed on 146 patients with pancreatobiliary diseases by using high-frequency, thin ultrasonic probes, and the usefulness of the new technique in diagnosis of pancreatic diseases was reported. The ultrasound probe could be inserted into the main pancreatic duct in 43 of 46 patients (93.5%), and images of the lesions could be obtained in 42 patients (91.3%). Endoluminal ultrasonography revealed a hypoechoic mass with clear margins and central echogenicity in patients with pancreatic carcinoma. Endoluminal ultrasonography showed normal pancreatic parenchyma as a fine reticular pattern and did not reveal the tumors surrounding the stenosis in patients with focal pancreatitis. Endoluminal ultrasonography in patients with intraductal papillary adenocarcinoma of the pancreas revealed cystic lesions with mural nodules more than 4 mm, mucus echoes, and solid tumors with mixed echo patterns. There were no severe complications, and acute pancreatitis occurred in none of 46 patients, but high-level serum amylase after examination occurred in 5 patients (10.9%). Endoluminal ultrasonography is useful for differential diagnosis in patients with small pancreatic tumors or cystic lesions, especially intraductal papillary tumors of the pancreas. Endoluminal ultrasonography is recommended as a precise examination for the diagnosis of cystic lesions of the pancreas or stenosis of the main pancreatic duct after ERCP and EUS.     

Islet cell tumors of the pancreas The diagnostic value of endoscopic retrograde pancreatography

Eleven cases of pancreatic islet cell tumors were reviewed to compare diagnostic ability of endoscopic retrograde pancreatography (ERP) with other imaging modalities. ERP localized three out of five tumors studied and showed a suspicious finding in an additional patient. All these tumors were located in the pancreatic head. Thus, the diagnostic ability of ERP was superior in the head portion, where recognition of a tumor is often difficult at the operation, and a more complicated procedure is required for removal. Nonfunctioning islet cell tumors were localized by hypervascularity on angiogram, but retroperitoneal leiomyosarcoma remained to be excluded in one patient. ERP with an indwelling balloon catheter revealed the pancreatic origin of the tumors and precisely determined the line of pancreatic resection by vividly visualizing pancreatic duct obstruction and intact distal branches. We conclude that ERP is helpful to localize functioning islet cell tumors of the pancreas especially in the head portion and plays an important role for planning resection of nonfunctioning islet cell tumors.     

Islet cell tumors of the pancreas. The diagnostic value of endoscopic retrograde pancreatography

Eleven cases of pancreatic islet cell tumors were reviewed to compare diagnostic ability of endoscopic retrograde pancreatography (ERP) with other imaging modalities. ERP localized three out of five tumors studied and showed a suspicious finding in an additional patient. All these tumors were located in the pancreatic head. Thus, the diagnostic ability of ERP was superior in the head portion, where recognition of a tumor is often difficult at the operation, and a more complicated procedure is required for removal. Nonfunctioning islet cell tumors were localized by hypervascularity on angiogram, but retroperitoneal leiomyosarcoma remained to be excluded in one patient. ERP with an indwelling balloon catheter revealed the pancreatic origin of the tumors and precisely determined the line of pancreatic resection by vividly visualizing pancreatic duct obstruction and intact distal branches. We conclude that ERP is helpful to localize functioning islet cell tumors of the pancreas especially in the head portion and plays an important role for planning resection of nonfunctioning islet cell tumors.     

Endosonographic features predictive of benign and malignant gastrointestinal stromal cell tumours

BACKGROUND/AIM: Some endoscopic ultrasonographic (EUS) features have been reported to be suggestive of malignancy in gastrointestinal stromal cell tumours (SCTs). The aim of this study was to assess the predictive value of these features for malignancy. METHODS: A total of 56 histologically proven cases of SCT studied by EUS between 1989 and 1996 were reviewed. There were 42 gastric tumours, 12 oesophageal tumours, and two rectal tumours. The tumours were divided into two groups: (a) benign SCT, comprising benign leiomyoma (n = 34); (b) malignant or borderline SCT (n = 22), comprising leiomyosarcoma (n = 9), leiomyoblastoma (n = 9), and leiomyoma of uncertain malignant potential (n = 4). The main EUS features recorded were tumour size, ulceration, echo pattern, cystic spaces, extraluminal margins, and lymph nodes with a malignant pattern. The two groups were compared by univariate and multivariate analysis. RESULTS: Irregular extraluminal margins, cystic spaces, and lymph nodes with a malignant pattern were most predictive of malignant or borderline SCT. Pairwise combinations of the three features had a specificity and positive predictive value of 100% for malignant or borderline SCT, but a sensitivity of only 23%. The presence of at least one of these three criteria had 91% sensitivity, 88% specificity, and 83% predictive positive value. In multivariate analysis, cystic spaces and irregular margins were the only two features independently predictive of malignant potential. The features most predictive of benign SCTs were regular margins, tumour size < or = 30 mm, and a homogeneous echo pattern. When the three features were combined, histology confirmed a benign SCT in all cases. CONCLUSIONS: The combined presence of two out of three EUS features (irregular extraluminal margins, cystic spaces, and lymph nodes with a malignant pattern) had a positive predictive value of 100% for malignant or borderline gastrointestinal SCT. Tumours less than 30 mm in diameter with regular margins and a homogeneous echo pattern are usually benign.     

The reliability of EUS for the diagnosis of chronic pancreatitis: interobserver agreement among experienced endosonographers

BACKGROUND: Endoscopic ultrasound (EUS) is a minimally invasive, low risk method of diagnosis for chronic pancreatitis (CP). The degree to which endosonographers agree on the features and diagnosis of CP is unknown. For EUS to be considered an accurate test for CP, there must be good interobserver agreement. METHODS: Forty-five pancreatic EUS examinations were videotaped by 3 experienced endosonographers. Examinations from 33 patients with suspected CP based on typical symptoms, as well as 12 control patients without suspected CP, were included. Eleven experienced endosonographers ("experts") who were blinded to clinical information independently evaluated all videotaped examinations for the presence of CP and the following 9 validated features of CP: echogenic foci, strands, lobularity, cysts, stones, duct dilatation, duct irregularity, hyperechoic duct margins, and visible side branches. The experts also ranked (most to least) which features they believed to be the most indicative of CP. Interobserver agreement was expressed as the kappa (kappa) statistic. RESULTS: There was moderately good overall agreement for the final diagnosis of CP (kappa = 0.45). Agreement was good for individual features of duct dilatation (kappa = 0.6) and lobularity (kappa = 0.51) but poor for the other 7 features (kappa < 0.4). The expert panel had consensus or near consensus agreement (greater than 90%) on 206 of 450 (46%) individual EUS features including 22 of 45 diagnoses of CP. Agreement on the final diagnosis of CP was moderately good for those trained in third tier fellowships (kappa = 0.42 +/- 0.03) and those with more than 1100 lifetime pancreatic EUS examinations (kappa = 0.46 +/- 0.05). The presence of stones was regarded as the most predictive feature of CP by all endosonographers, followed by visible side branches, cysts, lobularity, irregular main pancreatic duct, hyperechoic foci, hyperechoic strands, main pancreatic duct dilatation, and main duct hyperechoic margins. The most common diagnostic criterion for the diagnosis of CP was the total number of features (median 4 or greater, range 3 or greater to 5 or greater). CONCLUSIONS: EUS is a reliable method for the diagnosis of chronic pancreatitis with good interobserver agreement among experienced endosonographers. Agreement on the EUS diagnosis of chronic pancreatitis is comparable to other commonly used endoscopic procedures such as bleeding ulcer stigmata and computed tomography of the brain for stroke localization and better than the physical diagnosis of heart sounds.     

Intraductal papillary mucinous neoplasm and acute pancreatitis

Intraductal papillary mucinous neoplasms (IPMNs) are cystic pancreatic tumors that arise from the pancreatic ducts and are increasingly reported worldwide. Both benign and malignant tumors of the pancreas are thought to contribute to recurrent pancreatitis possibly by pancreatic duct obstruction, and IPMNs contribute to a major share of this burden. The rate of acute pancreatitis (AP) in IPMN patients in the largest published surgical series has varied from 12% to 67%. IPMN may be categorized into 3 forms on the basis of the areas of involvement: main pancreatic duct (MD-IPMN), side branch (SB-IPMN), or combined. Both MD-IPMN and SB-IPMN may be the cause of pancreatitis. The risk of AP seems to be similar with both main duct IPMN and SB-IPMN, although data are controversial. AP in IPMN patients is not severe and often recurs without treatment. The rate of AP does not seem to differ among benign and malignant IPMNs, and the correlation between the malignant potential and the occurrence of AP is ill defined. AP seems to occur more often in patients with IPMN that in those with usual pancreatic adenocarcinoma possibly because of obstruction of the main duct by thick, abundant mucus secretion. Although the Sendai guidelines recommend surgical resection in patients with SB-IPMN with AP, data are controversial. Moreover, in patients with an episode of pancreatitis, the finding of pancreatic cysts is often attributed to pseudocysts or fluid collections that make the diagnosis of IPMN less suspicious. Future longitudinal and prospective studies to understand the natural history of AP in patients with IPMN are required to better manage patients with recurrent AP in the setting of IPMN.     

Hemosuccus pancreaticus due to intraductal papillary-mucinous carcinoma of the pancreas

A 72-year-old female was referred to our hospital for evaluation of a hyperechoic mass in the pancreatic head with ultrasound sonography. She had no symptom expect slight anemia (Hb 11.3 g/dl). On endoscopy, blood was expelled from the orifice of the major duodenal papilla, but excretion of mucus was not detected. Endoscopic retrograde pancreatography revealed an irregular defect in the main pancreatic duct at the head of the pancreas. Computed tomography revealed a 2-cm mass with a low density lesion in the pancreas head. On suspicion of malignant tumor of the pancreas, pylorus-preserving pancreaticoduodenectomy was performed. Histological diagnosis was intraductal papillary-mucinous carcinoma without mucin hypersecretion. It grew within the inferior branch of the main pancreatic duct, and the top of the tumor stood out into the main pancreatic duct. As the causes of hemosuccus pancreaticus, pancreatic benign diseases, for example, chronic pancreatitis, pseudocyst, arterial aneurysm and pseudoaneurysm, are known, but pancreatic tumors are rare. In particular, this may be the first report of hemosuccus pancreaticus induced by intraductal papillary-mucinous carcinoma of the pancreas without mucin hypersecretion.     

Laparoscopic pancreatic surgery: its indications and techniques: from the viewpoint of limiting the indications

Indications in the field of pancreatic surgery should be limited considering the technical difficulties and the characteristics of pancreatic diseases. Benign or low‐grade malignant tumors, including pseudocysts, islet tumors, and cystic tumors, are indications for distal pancreatectomy. Islet tumors such as insulinomas are good candidates for this procedure when they are located near splenic vessels or the main pancreatic duct and enucleation is considered inappropriate. Techniques of laparoscopic distal pancreatectomy with/without splenectomy and laparoscopy‐assisted distal pancreatectomy indicated in low‐grade malignant tumors such as mucinous cystadenoma are described. Insulinoma is one of the best candidates for enucleation because many of the cases are solitary and benign. The technique of enucleation is also described.     

梗阻性黄疸的MRCP表现（附47例报告并文献复习）

目的 总结梗阻性黄疸的MRCP表现,提高其诊断的准确性.方法 回顾分析47例经手术和病理证实的梗阻性黄疸患者的MRCP表现.结果 恶性梗阻性黄疸25例,其中肝门胆管癌6例,胆囊癌2例,胆总管腺癌4例,胰头癌、十二指肠腺癌各3例,胰头转移瘤7例.良性梗阻性黄疸22例,其中炎性梗阻3例,胆囊或胆总管结石伴炎症13例,术后瘢痕、胆总管囊肿、十二指肠息肉各2例.恶性梗阻性黄疸的典型MRCP表现为肝内胆管呈"藤蔓"征,胆管突然截断,断端圆钝形态不规则,呈偏心性或向心性狭窄或充盈缺损.良性梗阻性黄疸的MRCP表现为肝内胆管呈"枯树枝"征,胆总管逐渐变窄或其内形态规则的充盈缺损,断端锐利、平直或倒杯口状或圆锥状.结论 MRCP是诊断良、恶性梗阻性黄疸的有效方法.     

Endoscopic ultrasound elastography for evaluation of lymph nodes and pancreatic masses： A multicenter study

AIM： To evaluate the ability of endoscopic ultrasound （EUS） elastography to distinguish benign from malignant pancreatic masses and lymph nodes.
METHODS： A multicenter study was conducted and included 222 patients who underwent EUS examination with assessment of a pancreatic mass （n = 121） or lymph node （n = 101）, The classification as benign or malignant, based on the real time elastography pattern, was compared with the classification based on the B-mode EUS images and with the final diagnosis obtained by EUS-guided fine needle aspiration （EUS- FNA） and/or by surgical pathology. An interobserver study was performed.
RESULTS： The sensitivity and specificity of EUS elastography to differentiate benign from malignant pancreatic lesions are 92.3% and 80.0%, respectively, compared to 92.3% and 68.9%, respectively, for the conventional B-mode images. The sensitivity and specificity of EUS elastography to differentiate benign from malignant lymph nodes was 91.8% and 82.5%, respectively, compared to 78.6% and 50.0%, respectively, for the B-mode images. The kappa coefficient was 0.785 for the pancreatic masses and 0.657 for the lymph nodes.
CONCLUSION： EUS elastography is superior compared to conventional B-mode imaging and appears to be able to distinguish benign from malignant pancreatic masses and lymph nodes with a high sensitivity, specificity and accuracy. It might be reserved as a second line examination to help characterise pancreatic masses after negative EUS-FNA and might increase the yield of EUS-FNA for lymph nodes.     

The role of multi-detector-row computed tomograph in the diagnosis of intraductal papillary-mucinous tumors of the pancreas in comparison to endoscopic retrograde pancreatography, endoscopic ultrasonography, magnetic resonance cholangiopancreatography]

Thirty patients with intraductal papillary-mucinous tumor (IPMT) of the pancreas underwent multidetector-row CT (MD-CT) in addition to endoscopic retrograde pancreatography (ERP), and, in 27 cases magnetic resonance cholangiopancreatography (MRCP) and endoscopic ultrasonography (EUS). The usefulness of MD-CT was investigated by comparing various imaging methods of the communication from the main pancreatic duct (MPD) to patulous/bulging papilla in addition to the indices for benign or malignant disease, the degree of dilation of the MPD, localization and size of cystic lesions, and presence or absence of neoplastic lesions, such as thickened walls and septa, intramural nodule, solid mass. With MD-CT, dilation of the MPD and localization and size of cystic lesions were accurately assessed, even in patients with obstruction of the main pancreatic duct in whom ERP was difficult to perform regardless of the presence or absence of massive amount of mucus. MD-CT with reconstructive imaging, such as MPR imaging and CPR imaging, allowed us to assess communication with the MPD and patulous/bulging papilla easier than MRCP. In our study, MD-CT was useful in the evaluation of thickened walls and septa that are predictive factors of malignancy in IPMT.     

A case of concurrent pancreatic intraepithelial neoplasia and type 1 autoimmune pancreatitis with marked pancreatic duct dilatation

The case patient was a previously healthy 82-year-old male. Abdominal ultrasound during a medical check-up revealed a dilatation of the main pancreatic duct, and the patient was referred to our hospital for closer examination. Contrast-enhanced computed tomography (CT) revealed a low-density mass of 20 mm in the pancreatic head–body transitional area. Magnetic resonance cholangiopancreatography (MRCP) revealed marked dilatation of the main pancreatic duct and branches in the body–tail. On endoscopic ultrasonography (EUS), a hypoechoic mass with irregular shape was detected, which was consistent with the area of pancreatic duct stenosis. Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) and pancreatic juice cytology were performed; however, there were no malignant findings. Serum IgG4 levels had increased to 299 mg/dL. Cancer of the pancreatic head was suspected and a pancreaticoduodenectomy was thus performed. Macroscopic findings included a white mass with indistinct border in the constricted part of the pancreatic duct and mottled fatty replacement of the pancreatic head. Pathologically, a large amount of IgG4-positive plasma cells was found in the white mass, with storiform fibrosis and obstructive phlebitis, which led to the diagnosis of type 1 autoimmune pancreatitis (AIP). Furthermore, scattered low–high grade pancreatic intraepithelial neoplasia lesions were observed throughout the pancreatic head, separately from the AIP lesion. This is an interesting case that suggests an association between AIP and pancreatic cancer. We report the case with a review of relevant literature.