Management of pancreatic masses

Innovative method for the diagnosis of bile duct lesions using a novel tapered-tip sheath system to facilitate biliary biopsies

BACKGROUND AND AIMS

Pathologic evaluation of bile duct lesions is crucial for a definitive diagnosis and determination of an appropriate therapeutic strategy; however, current methods are limited by several challenges. This study evaluated the impact of a novel tapered-tip sheath system on biliary stricture diagnosis.

METHODS

This observational study evaluated 47 consecutive patients who underwent transpapillary biliary stricture biopsy using the novel tapered-tip sheath system from July 2020 to March 2022 compared with 51 historical control subjects undergoing conventional biopsies. Technical success rate, total biopsy time, number of biopsy specimens, adequate tissue sampling rate, adverse events, and diagnostic performance for biliary strictures were assessed.

RESULTS

The technical success rate was favorable in both groups, showing no significant difference (97.9% [46 of 47] vs 88.2% [45 of 51], P = .114). However, the total biopsy time was significantly shorter in the novel system group (3.7 vs 7.7 minutes, P < .001). The number of biopsy specimens did not differ between the groups; however, the novel system group had significantly more cases in which ≥3 tissue samples could be obtained (71.7% [33 of 46] vs 51.1% [23 of 45], P = .043), a higher adequate tissue sampling rate (88.2% vs 66.4%, P < .001), and fewer adverse events (6.4% vs 21.6%, P = .043). Although the diagnostic specificity of both groups was 100%, the novel system group had significantly higher diagnostic sensitivity and accuracy (82.1% vs 50% [P = .004] and 84.8% vs 55.5% [P = .005], respectively).

CONCLUSIONS

The novel tapered-tip sheath system is a promising tool for biliary stricture diagnosis.

Evaluation of endoscopic ultrasound-guided fine-needle biopsy for preoperative pancreatic solid lesions

OBJECTIVES

Obtaining an accurate preoperative diagnosis is crucial. This study aimed to evaluate the diagnostic accuracy and utility of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) for preoperative pancreatic solid lesions.

MATERIALS AND METHODS

We retrospectively assessed all patients who underwent endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) or EUS-FNB to evaluate solid pancreatic lesions preoperatively at our center between July 2013 and June 2020. We enrolled 71 patients who underwent EUS-FNA using a 22 G conventional needle (FNA group) and 34 patients who underwent EUS-FNB using a 22 G Franseen needle (FNB group). Overall, 105 patients were analyzed. We employed propensity-matched analysis and adjusted the confounders.

RESULTS

No procedural adverse events were encountered. Both groups showed no significant differences in the procedure time, technical success rate, and rate of operator changes from trainee to expert. Regarding diagnostic accuracy, the FNB group (88.2%; 30/34) was higher but not significantly different from the FNA group (85.3%; 29/34) (p > .99). Furthermore, the FNB group (median 2, IQR;2-3) had a significantly lower number of punctures than the FNA group (median 3, IQR; 2-4) (p = .01).

CONCLUSIONS

The FNB needle provides higher diagnostic accuracy and requires significantly fewer punctures than conventional needles even at facilities with no available rapid on-site evaluation. Thus, using the FNB needle can be useful for preoperative pancreatic solid lesions.

Diffuse Pancreatic Cancer Mimicking Autoimmune Pancreatitis

The characteristic finding of sausage-shaped pancreas or capsule-like rim facilitates the diagnosis of autoimmune pancreatitis. We herein report a case of a 67-year-old man showing a sausage-shaped, enlarged pancreas with a capsule-like rim on computed tomography. Furthermore, endoscopic retrograde cholangiopancreatography demonstrated diffuse narrowing of the main pancreatic duct, in addition to stenosis of the lower bile duct. Finally, we were able to diagnose pancreatic cancer in this patient by an endoscopic ultrasound-guided fine-needle aspiration biopsy following peroral cholangioscopy and bile cytology. This report emphasizes the significance of pathological confirmation before starting treatment, even in cases with diffuse pancreatic enlargement.

Early pancreatic cancer - The role of endoscopic ultrasound with or without tissue acquisition in diagnosis and staging

Pancreatic cancer (PC) is one of the deadliest cancers with a 5-year overall survival of less than 6%. Due to its insidious clinical course and unspecific symptoms, the diagnosis is usually late, with only 15-20% patients presenting with potentially curable disease. It is, therefore, extremely important to identify patients with PC at early stages of the disease when tumors may be amenable to surgical resection. For unresectable and borderline resectable PC it is consensual to perform a biopsy to have a cyto/histological confirmation of malignancy before treatment. However, for patients presenting with promptly resectable disease, the role of biopsy is more debatable. There are, in the literature, arguments both for and against the usefulness of a preoperative biopsy. Endoscopic ultrasound (EUS) is an important technique assisting in the diagnosis and staging of PC. EUS-guided tissue acquisition is a well-established tool to demonstrate the malignant nature of a pancreatic lesion. This review focuses on the role of EUS in the diagnosis and staging of PC, and highlights the controversy related to the role of EUS-guided tissue acquisition in the preoperative assessment of patients presenting with promptly resectable tumors (early PC).

Preoperative EUS-guided FNA: effects on peritoneal recurrence and survival in patients with pancreatic cancer

BACKGROUND AND AIMS

EUS-guided FNA (EUS-FNA) is an accurate and relatively safe tissue confirmation method for pancreatic cancer. However, there is concern that this procedure may spread tumor cells along the needle track or within the peritoneum. We aimed to estimate the effect of preoperative EUS-FNA on the risk of peritoneal recurrence and long-term outcomes in resected pancreatic cancer.

METHODS

We retrospectively reviewed records of patients diagnosed with pancreatic cancer who had undergone curative resection between 2009 and 2013 to investigate the overall survival, cancer-free survival, and peritoneal recurrence. Peritoneal recurrence was diagnosed based on image findings or cytology-confirmed ascites.

RESULTS

Of 411 patients, 90 underwent preoperative EUS-FNA (EUS-FNA group), whereas 321 did not (non-EUS-FNA group). The median length of follow-up was 16.2 months (range, 2-46). Peritoneal recurrence occurred in 131 patients: 30% (27/90) in the EUS-FNA group versus 32% (104/321) in the non-EUS-FNA group (P = .66). Cancer-free survival or overall survival was not significantly different between the 2 groups: median overall survival of 25.3 months in the EUS-FNA group versus 23.7 months in the non-EUS-FNA group (P = .36) and median cancer-free survival of 12.7 months in the EUS-FNA group versus 11.6 months in the non-EUS-FNA group (P = .38).

CONCLUSIONS

Preoperative EUS-FNA for pancreatic cancer was not associated with an increased rate of peritoneal recurrence or mortality. Therefore, EUS-FNA is an accurate and safe method to obtain suspicious pancreatic mass tissue.

The Surgeon's Role in Treating Chronic Pancreatitis and Incidentally Discovered Pancreatic Lesions

Chronic pancreatitis and incidentally discovered pancreatic lesions present significant diagnostic and therapeutic challenges for surgeons. While both decompressive and resection procedures have been described for treatment of chronic pancreatitis, optimal management must be tailored to each patient's individual disease characteristics, parenchymal morphology, and ductal anatomy. Surgeons should strive to achieve long-lasting pain relief while preserving native pancreatic function. For patients with incidentally discovered pancreatic lesions, differentiating benign, pre-malignant, and malignant lesions is critical as earlier treatment is thought to result in improved survival. The purpose of this evidence-based manuscript is to review the presentation, workup, surgical management, and associated outcomes for patients with chronic pancreatitis or incidentally discovered solid and cystic lesions of the pancreas.

Sarcoidosis with Pancreatic Mass, Endobronchial Nodules, and Miliary Opacities in the Lung

Sarcoidosis affects multiple organs and rarely has unusual manifestations. A 78-year-old woman was referred to our hospital for coughing symptoms. A chest computed tomography (CT) scan revealed bilateral diffuse miliary patterns and right pleural effusion. Bronchoscopy showed multiple nodules in the carina and the bronchus intermedius. A CT scan of her abdomen revealed hypovascular lesions involving the pancreatic head and body. A transbronchial lung biopsy, bronchial mucosal biopsy, and endoscopic ultrasound-guided fine-needle aspiration of the pancreatic mass demonstrated non-caseating granulomas. We diagnosed the patient with sarcoidosis. She received no treatment for sarcoidosis and has been followed up for one year, during which no pulmonary disease progression had been observed and the pancreatic masses partially regressed.

A rare case of IgG4-related systemic disease manifesting with pancreatic head mass mimicking borderline resectable cancer

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Diagnostic algorithm for pancreatic head mass.

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Differential diagnosis between pancreatic cancer and mass forming autoimmune pancreatitis.

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Diagnosis and treatment of IgG4-related systemic disease.

INTRODUCTION

Autoimmune pancreatitis (AIP) is a rare pancreatic disorder among chronic pancreatitis that can mimick pancreatic cancer (PC). Patients with type 1 AIP usually present obstructive jaundice associated with high level of IgG4 in serum and a pancreatic mass at radiological imaging; these disorders may be associated with other organs lesions presenting the same histopathological features, and in these cases AIP should be considered a pancreatic localization of an IgG4-related systemic disease.

PRESENTATION OF CASE

We report the case of a young man with initial suspect of PC to be treated with surgery, and final diagnosis of AIP in the context of an IgG4-related systemic disease.

DISCUSSION

Because of its similar features, several algorithms have been proposed for AIP diagnosis, based on combination of clinical/serological and radiological criteria. However, histology represents the only way to obtain definitive diagnosis, even if sometimes it is difficult to obtain biological samples.

CONCLUSION

IgG4-related systemic disease must be taken into account among differential diagnosis during the workup for PC, in order to avoid unnecessary surgery.

Comparative MRI analysis of morphologic patterns of bile duct disease in IgG4-related systemic disease versus primary sclerosing cholangitis

OBJECTIVE

The purpose of this study was to perform a retrospective MRI-based comparative analysis of the morphologic patterns of bile duct disease in IgG4-related systemic disease (ISD, also called autoimmune pancreatitis) compared with primary sclerosing cholangitis (PSC) and the autoimmune liver diseases autoimmune hepatitis and primary biliary cirrhosis.

MATERIALS AND METHODS

This study included 162 consecutively registered patients (47 with ISD, 73 with PSC, and 42 with autoimmune liver diseases). Two abdominal radiologists retrospectively reviewed MR images in consensus. Imaging findings on the bile ducts, liver, pancreas, and other organs were analyzed to establish disease patterns.

RESULTS

ISD was associated with contiguous thickening of intrahepatic and extrahepatic bile ducts (p<0.001), pancreatic parenchymal abnormalities (p<0.001), renal abnormalities (p<0.001), and gallbladder wall thickening (p<0.03). The severity of common bile duct wall thickness was significantly different in ISD (p<0.001). The mean single wall thickness in the ISD group was 3.00 (SD, 1.47) mm, in the PSC group was 1.89 (SD, 0.73) mm, and in the autoimmune liver disease group was 1.80 (SD, 0.67) mm. PSC was associated with liver parenchymal abnormalities (p<0.001). We did not find statistical significance between the three groups in location (p=0.220) or length (p=0.703) of extrahepatic bile duct strictures, enhancement of bile duct stricture (p=0.033), upper abdominal lymphadenopathy, or retroperitoneal fibrosis. Although presence of intrahepatic bile duct stricture was statistically significant when all three groups were compared, it was not useful for differentiating ISD from PSC.

CONCLUSION

The presence of continuous as opposed to skip disease in the bile ducts, gallbladder involvement, and single-wall common bile duct thickness greater than 2.5 mm supports a diagnosis of ISD over PSC. ISD and PSC could not be differentiated on the basis of location and length of common bile duct stricture.

Influence of the safety and diagnostic accuracy of preoperative endoscopic ultrasound-guided fine-needle aspiration for resectable pancreatic cancer on clinical performance

AIM: To evaluate the safety and diagnostic accuracy of endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in a cohort of pancreatic cancer patients.

METHODS: Of 213 patients with pancreatic cancer evaluated between April 2007 and August 2011, 82 were thought to have resectable pancreatic cancer on the basis of cross-sectional imaging findings. Of these, 54 underwent EUS-FNA before surgery (FNA+ group) and 28 underwent surgery without preoperative EUS-FNA (FNA- group).

RESULTS: All 54 lesions were visible on EUS, and all 54 attempts at FNA were technically successful. The diagnostic accuracy according to cytology and histology findings was 98.1% (53/54) and 77.8% (42/54), respectively, and the total accuracy was 98.1% (53/54). One patient developed mild pancreatitis after EUS-FNA but was successfully treated by conservative therapy. No severe complications occurred after EUS-FNA. In the FNA+ and FNA- groups, the median relapse-free survival (RFS) was 742 and 265 d, respectively (P = 0.0099), and the median overall survival (OS) was 1042 and 557 d, respectively (P = 0.0071). RFS and OS were therefore not inferior in the FNA+ group. These data indicate that the use of EUS-FNA did not influence RFS or OS, nor did it increase the risk of peritoneal recurrence.

CONCLUSION: In patients with resectable pancreatic cancer, preoperative EUS-FNA is a safe and accurate diagnostic method.

Focal autoimmune pancreatitis: Radiological characteristics help to distinguish from pancreatic cancer

AIM: To identify the radiological characteristics of focal autoimmune pancreatitis (f-AIP) useful for differentiation from pancreatic cancer (PC).

METHODS: Magnetic resonance imaging (MRI) and triple-phase computed tomography (CT) scans of 79 patients (19 with f-AIP, 30 with PC, and 30 with a normal pancreas) were evaluated retrospectively. A radiologist measured the CT attenuation of the pancreatic parenchyma, the f-AIP and PC lesions in triple phases. The mean CT attenuation values of the f-AIP lesions were compared with those of PC, and the mean CT attenuation values of pancreatic parenchyma in the three groups were compared. The diagnostic performance of CT attenuation changes from arterial phase to hepatic phase in the differentiation between f-AIP and PC was evaluated using receiver operating characteristic (ROC) curve analysis. We also investigated the incidence of previously reported radiological findings for differentiation between f-AIP and PC.

RESULTS: The mean CT attenuation values of f-AIP lesions in enhanced phases were significantly higher than those of PC (arterial phase: 60 ± 7 vs 48 ± 10, P < 0.05; pancreatic phase: 85 ± 6 vs 63 ± 15, P < 0.05; hepatic phase: 95 ± 7 vs 63 ± 13, P < 0.05). The mean CT attenuation values of f-AIP lesions were significantly lower those of uninvolved pancreas and normal pancreas in the arterial and pancreatic phase of CT (P < 0.001, P < 0.001), with no significant difference at the hepatic phase or unenhanced scanning (P = 0.4, P = 0.1). When the attenuation value increase was equal or more than 28 HU this was considered diagnostic for f-AIP, and a sensitivity of 87.5%, specificity of 100% and an area under the ROC curve of 0.974 (95%CI: 0.928-1.021) were achieved. Five findings were more frequently observed in f-AIP patients: (1) sausage-shaped enlargement; (2) delayed homogeneous enhancement; (3) hypoattenuating capsule-like rim; (4) irregular narrowing of the main pancreatic duct (MPD) and/or stricture of the common bile duct (CBD); and (5) MPD upstream dilation ≤ 5 mm.

CONCLUSION: Analysis of a combination of CT and MRI findings could improve the diagnostic accuracy of differentiating f-AIP from PC.

18-Fluorodeoxyglucose positron emission tomography does not aid in diagnosis of pancreatic ductal adenocarcinoma

BACKGROUND & AIMS

There are no accurate and reliable tools for diagnosis of early stage pancreatic ductal adenocarcinoma (PDA) or small metastatic lesions. It is also a challenge to differentiate PDA from focal mass-forming pancreatitis (FMP). There is controversy regarding the efficacy of 18-fluorodeoxyglucose positron-emission tomography (FDG-PET) in the diagnosis of PDA. We investigated whether FDG-PET provides information that, combined with data from other imaging techniques, can aid in decision making for patients with suspected PDA.

METHODS

We performed a retrospective analysis of data collected from 232 consecutive patients with suspected PDA at Kobe University Hospital from January 2006 through June 2012. All patients underwent a diagnostic imaging protocol that included multidetector row computed tomography, superparamagnetic iron oxide-enhanced magnetic resonance imaging, and FDG-PET. Based on endoscopic ultrasonography, fine-needle aspiration biopsy, or endoscopic retrograde cholangiopancreatography analyses, 218 patients had PDA (89 underwent resection and 129 did not) and 14 patients had FMP (8 had focal mass-forming chronic pancreatitis and 6 had focal mass-forming autoimmune pancreatitis).

RESULTS

FDG-PET detected 50% of stages 0 and I, 91.9% of stage II, 100% of stage III, and 96.8% of stage IV tumors. Detection was affected significantly by tumor size (P = .024) and T stage (P = .023) in resected tumors. Multidetector row computed tomography detected significantly more liver metastases than FDG-PET. Few para-aortic lymph node or peritoneal metastases were detected by FDG-PET. FDG-PET correctly identified 11 of the 14 patients with FMP (5 of 8 with focal mass-forming chronic pancreatitis and 6 of 6 with focal mass-forming autoimmune pancreatitis).

CONCLUSIONS

FDG-PET is not effective in detecting early stage PDA and small metastases, or in differentiating PDA from FMP. Combining FDG-PET with current diagnostic techniques for PDA did not provide any decisive information, therefore it should not be included in this analysis.

Clinical differences between mass-forming autoimmune pancreatitis and pancreatic cancer

OBJECTIVE

Autoimmune pancreatitis (AIP) needs to be differentiated from pancreatic cancer (PC). We aimed to clarify the findings specific for AIP by comparing the clinical differences between mass-forming AIP and PC.

MATERIAL AND METHODS

We retrospectively compared 36 patients with mass-forming AIP and 60 with PC without metastasis regarding clinical, imaging, serological, histological differences and other organ involvement (OOI). We evaluated the sensitivity, specificity and accuracy of these findings for the differential diagnosis between AIP and PC.

RESULTS

The findings 100% specific for AIP were a capsule-like rim on computed tomography (CT), skipped lesion of main pancreatic duct (MPD) on endoscopic retrograde pancreatography (ERP) or magnetic resonance cholangiopancreatography (MRCP), γ-globulin > 2 g/dl, OOI (extrapancreatic biliary stricture, salivary gland swelling and retroperitoneal fibrosis) and ruling out PC by histopathological findings of endoscopic ultrasonography-guided fine-needle aspiration. The findings over 90% specific were IgG4 > 280 mg/dl (98%), IgG > 1800 mg/dl (97%), maximal diameter of upstream MPD < 5 mm on MRCP (95%) and IgG4 > 135 mg/dl (94%), respectively.

CONCLUSIONS

Clinical, imaging, serological, histological findings and OOI differed between mass-forming AIP and PC. Capsule-like rim on CT, skipped lesion of MPD on ERP or MRCP, IgG4 > 280 mg/dl, and OOI were highly specific findings for AIP. These findings are useful in the differential diagnosis of mass-forming AIP from PC.

Magnetic resonance imaging findings of the mass-forming type of autoimmune pancreatitis: comparison with pancreatic adenocarcinoma

PURPOSE

To determine the characteristic magnetic resonance imaging (MRI) features of mass-forming autoimmune pancreatitis (AIP), which allow its differentiation from pancreatic adenocarcinoma (PAC).

MATERIALS AND METHODS

MR images of 37 patients with either pathologically proven, mass-forming AIPs (n = 9) or PACs (n = 28) were retrospectively reviewed. The pancreatic MR protocol included unenhanced images, contrast-enhanced dynamic images, diffusion-weighted imaging (DWI), and MR-cholangiopancreatography (MRCP). Two reviewers analyzed the MR images regarding the number, location, morphologic features, and enhancement degree and pattern of the lesions as well as secondary changes of the pancreatic parenchyma, the biliary and pancreatic ducts. The size and apparent diffusion coefficient (ADC) values of the lesions were measured.

RESULTS

Although sensitivities were low (28.6%-44.4%), specificities of multiplicity, capsule-like rim enhancement, and skipped stricture of the biliary or pancreatic duct in mass-forming AIP were high (100%). Sensitivities and specificities of irregular or geographic shape, delayed enhancement, and a low ADC value <1.26 × 10(-3) mm(2) /s in mass-forming AIP were favorable (71.4%-83.3% and 78.5%-89.3%).

CONCLUSION

Although to differentiate mass-forming AIP from pancreatic cancer is difficult, the combination of MRI findings including contrast-enhanced dynamic images, MRCP, and DWI can be a help.

A case of autoimmune pancreatitis showing narrowing of the main pancreatic duct after cessation of steroid therapy in the clinical course

Autoimmune pancreatitis (AIP) is characterized by irregular narrowing of the main pancreatic duct (MPD), and narrowing of the MPD is an essential criterion for the diagnosis of focal/segmental AIP according to the Japanese diagnostic criteria 2011. We report a 55-year-old man in whom magnetic resonance imaging showed two masses in the pancreatic head and tail and whose pancreatogram was normal at first. However, the two masses changed into diffuse swelling of the pancreas, and diffuse narrowing of the MPD appeared after the cessation of steroid therapy. Finally, we could diagnose this patient as having AIP according to the Japanese diagnostic criteria.

A focal mass-forming autoimmune pancreatitis mimicking pancreatic cancer with obstruction of the main pancreatic duct

INTRODUCTION AND BACKGROUND

Autoimmune pancreatitis (AIP) is a rare disease that closely mimics pancreatic cancer (PC) in its presentation. It is very important for clinicians to distinguish one from the other because their treatment and prognosis are vastly different. Typical radiological imaging findings, in particular observation of diffusely or segmentally narrowed main pancreatic duct (MPD) with an irregular wall by endoscopic retrograde cholangiopancreatography (ERCP), are essential for making the diagnosis of AIP. On the other hand, MPD obstruction is one of the most frequent features on ERCP.

CASE REPORT

We report a rare case of a patient with focal mass-forming AIP strongly suspected of being PC because of MPD obstruction on ERCP.

CONCLUSION

It was difficult to distinguish PC from AIP with current diagnostic modalities. We will continue to make an effort to distinguish between the two disorders to prevent unnecessary surgery.

Distinguishing pancreatic cancer from autoimmune pancreatitis

Both autoimmune pancreatitis (AIP) and pancreatic cancer frequently present with obstructive jaundice. However, AIP is a rare disease and its diagnosis carries vastly different therapeutic and prognostic implications compared with that of pancreatic cancer. The clinical challenge is to distinguish AIP from pancreatic cancer, because the price of misdiagnosis can be heavy. Recently, two strategies for differentiating AIP from pancreatic cancer were published, one from Japan and the other from the United States. The Japanese strategy relies on cross-sectional imaging, endoscopic retrograde pancreatogram, and serum IgG4. The American strategy uses imaging (CT scan), serology (serum IgG4), and evidence of other organ involvement (on CT scan) as the first tier of tests. If the differentiation cannot be made by these methods, a core biopsy of the pancreas, steroid trial, or surgical resection is recommended. The two strategies reflect differences in clinical practice and local preferences in the use of certain diagnostic tests. However, both strategies require thorough familiarity with the diseases and the tests being used.

Identification of a novel antibody associated with autoimmune pancreatitis

BACKGROUND

Autoimmune pancreatitis is characterized by an inflammatory process that leads to organ dysfunction. The cause of the disease is unknown. Its autoimmune origin has been suggested but never proved, and little is known about the pathogenesis of this condition.

METHODS

To identify pathogenetically relevant autoantigen targets, we screened a random peptide library with pooled IgG obtained from 20 patients with autoimmune pancreatitis. Peptide-specific antibodies were detected in serum specimens obtained from the patients.

RESULTS

Among the detected peptides, peptide AIP(1-7) was recognized by the serum specimens from 18 of 20 patients with autoimmune pancreatitis and by serum specimens from 4 of 40 patients with pancreatic cancer, but not by serum specimens from healthy controls. The peptide showed homology with an amino acid sequence of plasminogen-binding protein (PBP) of Helicobacter pylori and with ubiquitin-protein ligase E3 component n-recognin 2 (UBR2), an enzyme highly expressed in acinar cells of the pancreas. Antibodies against the PBP peptide were detected in 19 of 20 patients with autoimmune pancreatitis (95%) and in 4 of 40 patients with pancreatic cancer (10%). Such reactivity was not detected in patients with alcohol-induced chronic pancreatitis or intraductal papillary mucinous neoplasm. The results were validated in another series of patients with autoimmune pancreatitis or pancreatic cancer: 14 of 15 patients with autoimmune pancreatitis (93%) and 1 of 70 patients with pancreatic cancer (1%) had a positive test for anti-PBP peptide antibodies. When the training and validation groups were combined, the test was positive in 33 of 35 patients with autoimmune pancreatitis (94%) and in 5 of 110 patients with pancreatic cancer (5%).

CONCLUSIONS

The antibody that we identified was detected in most patients with autoimmune pancreatitis but also in some patients with pancreatic cancer, making it an imperfect test to distinguish between these two conditions.

A diagnostic strategy to distinguish autoimmune pancreatitis from pancreatic cancer

BACKGROUND & AIMS

Autoimmune pancreatitis (AIP) and pancreatic cancer (PaC) have similar presentations; a diagnostic strategy is needed to distinguish the 2 diseases.

METHODS

We compared computed tomography images (for pancreas and other organ involvement), serum IgG4 levels, histology data, and the response to steroids between patients with AIP (n = 48) and those with PaC (n = 100).

RESULTS

Pancreatic imaging findings stratified patients into 3 groups. Group 1 was highly suggestive of AIP, with diffuse pancreatic enlargement without group 3 features (n = 25, 100% AIP). Group 2 was indeterminate, with normal-sized pancreas or focal pancreatic enlargement without group 3 features (n = 20, 75% AIP). Group 3 was highly suggestive of PaC, with presence of >1 low-density mass, pancreatic duct cutoff, or upstream pancreatic atrophy (n = 103, 92% PaC). Although all patients in group 1 had AIP, only 20 of the 25 patients had increased serum IgG4 levels and/or other organ involvement. Of the patients in groups 2 and 3 who did not have cancer, all those with serum IgG4 levels >2-fold the upper limit of normal or a combination of increased serum IgG4 levels and other organ involvement (n = 15) had AIP. In AIP subjects without supportive serologic evidence or other organ involvement (n = 14), diagnosis required pancreatic core biopsy (n = 7), steroid trial (n = 5), or resection (n = 2).

CONCLUSIONS

PaC can be distinguished from AIP by pancreatic imaging, measurement of serum IgG4 levels, and determination of other organ involvement. However, a pancreatic core biopsy, steroid trial, or surgery is required for diagnosis in approximately 30% of patients with AIP.

Autoimmune pancreatitis: differences between the focal and diffuse forms in 87 patients

OBJECTIVES

Autoimmune pancreatitis (AIP) is a particular type of chronic pancreatitis that can be classified into diffuse and focal forms. The aim of this study was to analyze clinical and instrumental features of patients suffering from the diffuse and focal forms of AIP.

METHODS

AIP patients diagnosed between 1995-2008 were studied.

RESULTS

A total of 87 AIP patients (54 male and 33 female patients, mean age 43.4+/-15.3 years) were studied. Focal-type AIP was diagnosed in 63% and diffuse-type in 37%. Association with autoimmune diseases was observed in 53% of cases, the most common being ulcerative colitis (30%). Serum levels of IgG4 exceeded the upper normal limits (135 mg/dl) in 66% of focal AIP and in 27% of diffuse AIP (P=0.006). All patients responded to steroids. At recurrence non-steroid immunosuppressive drugs were successfully used in six patients. Recurrences were observed in 25% of cases, and were more frequent in focal AIP (33%) than in diffuse AIP (12%) (P=0.043), in smokers than in non-smokers (41% vs. 15%; P=0.011), and in patients with pathological serum levels of IgG4 compared to those with normal serum levels (50% vs. 12%; P=0.009). In all, 23% of the patients underwent pancreatic resections. Among patients with focal AIP, recurrences were observed in 30% of operated and in 34% of not operated patients.

CONCLUSIONS

Focal-type and diffuse-type AIP differ as regards clinical symptoms and signs. Recurrences occur more frequently in focal AIP than in diffuse AIP. The use of non-steroid immunosuppressants may be a therapeutic option in relapsing AIP.

Proteomic analysis of human bile from malignant biliary stenosis induced by pancreatic cancer

Stenosis of the common bile duct may be either due to benign (chronic pancreatitis) or malignant (cholangiocarcinoma, pancreatic adenocarcinoma) conditions. The benign nature of the stricture should be first confirmed in order to ensure appropriate therapy. Therefore, the identification of markers allowing discrimination between malignant and benign biliary stenosis would be very valuable in clinical practice. To this intent, we performed a proteomic analysis of bile samples from patients having a biliary stenosis caused by pancreatic adenocarcinoma. Bile samples were collected during endoscopic retrograde cholangiopancreatography and purified using different methods. The extracted proteins were then analyzed by SDS-PAGE and LC-MS/MS. A total of 127 proteins were identified, 34 of which have not been previously detected in proteomic studies of bile. Among them, several proteins have been described as potential biomarkers of pancreatic cancer. We extended our investigation by studying the expression of some of these pancreatic cancer markers in bile samples collected from patients with various etiologies of biliary stenosis including pancreatic cancer, cholangiocarcinoma, chronic pancreatitis, as well as gallstone-induced stenosis. Our data showed a conspicuous overexpression of CEACAM6 and MUC1 (CA19-9) in pancreatic cancer and cholangiocarcinoma samples, according to the hypothesis that bile fluid collects cancer-associated protein leaking from the tumor microenvironment. These results underline the interest of using bile as a source of biomarkers for the diagnosis of malignant biliary stenosis.

Autoimmune pancreatitis: an adolescent case and review of literature

We present a case of a 16-year-old adolescent boy with autoimmune pancreatitis and a review of the related literature. The patient was sent from a peripheral medical center, presenting with jaundice, pruritus, weight loss, and hyperglycemia of 20 days' duration. At admission, the patient was icteric, choluric, and acholic. His abdomen was soft and nontender, and the patient felt no pain in his abdomen. He had skin lesions because of scratching. Laboratory findings showed a blood glucose level of 135 mg%; total serum bilirubin, 29.4 mg%; direct bilirubin, 23 mg%; and alkaline phosphatase, 1100 IU/L. Abdominal ultrasound showed an enlarged head of the pancreas that was 30 x 35 mm. The parenchyma was slightly heterogeneous. Abdominal computed tomography showed an enlarged head of the pancreas with a normal body and tail, thickened duodenal wall, and dilated intra- and extrahepatic biliary tract, and the distal choledochus was not visible. Magnetic resonance imaging showed dilated intra- and extrahepatic biliary tract. The choledochus was not visible, and the cystic duct ended abruptly. The pancreas head was enlarged and homogenous, and there were no changes with contrast. Wirsung's duct was not dilated. Laparotomy was performed with a presumed diagnosis of pancreatic head tumor. The pancreas was diffusely indurated and enlarged; biopsy and intraoperative cholangiography were performed. The biliary tract was dilated with no duodenal passage of contrast, and the Wirsung's duct was not observed. Cholecystectomy was performed, and a transcystic drain was positioned. The histopathology was compatible with autoimmune pancreatitis. Prednisone treatment was started with good response. Autoimmune pancreatitis is a very rare entity among children and adolescents. It should be suspected when characteristic clinical signs and radiographic images are associated with a higher level of IgG4. Autoimmune pancreatitis is confirmed by biopsy. Treatment with prednisone often alleviates all the symptoms, as what happened in this case.

Grasp or brush for biliary sampling at endoscopic retrograde cholangiography? A blinded randomized controlled trial

OBJECTIVES

Brushing, the standard sampling method at endoscopic retrograde cholangiography (ERC), lacks sensitivity for cancer detection. We assessed a novel sampling method using a grasping basket.

METHODS

Fifty-six patients with a suspected malignant biliary stricture were randomized to biliary sampling at ERC using a basket (basket group, N = 30) or a brush (brush group, N = 26), followed by the alternate device. When deemed necessary, strictures were dilated (using 6-mm balloons exclusively). The primary end point was sensitivity for cancer detection at cytopathological examination of the first sample collected in each patient; the cytopathologist was blinded to clinical details and sampling method. All analyses followed an intention-to-treat principle.

RESULTS

All 56 patients had successful sampling with both techniques; 50 (89%) had a final diagnosis of malignant stricture. Sensitivity for cancer detection with the first sample collected in each patient was significantly higher in the basket compared to brush group (20/25 [80%]vs 12/25 [48%], respectively, P= 0.018, OR 4.33, 95% CI 1.24-15.21). Seventeen (34%) of the 50 sample pairs collected from malignant cases showed discordant cytopathological results: 15 patients had a positive basket and a negative brush result while two had the inverse association (P= 0.002, OR 7.5, 95% CI 1.65-47.44). Basketting more frequently yielded positive samples from malignant strictures in case of presampling balloon dilation (27/32 [84%]vs 10/18 [56%], respectively, P= 0.043, OR 4.32, 95% CI 1.14-16.37). Specificity was 100% (both methods).

CONCLUSION

Biliary sampling at ERC using a dedicated basket provided a significantly higher sensitivity for cancer detection than brushing; presampling stricture dilation significantly increased sensitivity.

The Japanese diagnostic criteria for autoimmune chronic pancreatitis: is it completely satisfactory?

OBJECTIVES

Autoimmune chronic pancreatitis (AIP) is a very attractive disease to clinicians in terms of its dramatic response to the oral steroid therapy in contrast to ordinary chronic pancreatitis. In the year 2002, the Japan Pancreas Society published the diagnostic criteria of AIP, and many clinicians around the world use these criteria for its diagnosis. The purpose of this study was to evaluate whether the Japanese criteria for the diagnosis of AIP are adequate or not.

METHODS

We retrospectively analyzed the clinical, radiologic, laboratory, and histologic features of 31 patients with AIP who have been successfully treated with oral corticosteroid. All the enrolled patients showed normalization or marked improvement in symptoms, laboratory, and imaging findings after steroid treatment.

RESULTS

The mean patients' age was 56 years (range, 32-78 years) and comprised 25 males and 6 females. Seven patients who responded to the steroid did not satisfy the Japanese imaging criterion because the extent of irregular narrowing was less than one third of the entire length of main pancreatic duct. Among these 7 patients, 1 patient did not meet the laboratory and histopathologic criteria as well. Another 2 patients fulfilled the Japanese imaging criterion only and showed normal IgG level, negative results of autoantibody measurements, and nondiagnostic pancreatic histopathology. Taken together, 9 (29%) of the 31 patients did not meet the Japanese diagnostic criteria for AIP, yet responded to the steroid.

CONCLUSIONS

Clinicians may miss a substantial portion of AIP patients who may benefit from steroid therapy when the diagnosis is confined to those who satisfy the criteria proposed by the Japan Pancreas Society. It is necessary to convene a worldwide consensus to develop an improved diagnostic criteria for AIP.