Lymphoplasmacytic sclerosing pancreatitis with obstructive jaundice: CT and pathology features. AJR Am J Roentgenol. 2004;183:915-921. [PMID: 15385281 DOI: 10.2214/ajr.183.4.1830915]

Qualitative and quantitative evaluation for morphological changes of the splenic artery in autoimmune pancreatitis: novel imaging findings for differentiation from pancreatic adenocarcinoma

PURPOSE

To determine whether morphological changes can occur in the splenic artery (SPA) of autoimmune pancreatitis (AIP) cases, and if present, to compare them with those in pancreatic adenocarcinoma (PAC) to clarify any arterial morphological differences between AIP and PAC.

METHODS

A total of 101 AIP cases were included in this study. The presence or absence of morphological change in the SPA was assessed, using arterial phase axial computed tomography images. Subsequently, imaging parameters (imaging pattern, capsule-like rim, other organ involvement, splenic vein [SPV] stenosis, and SPA calcification) were compared between cases with and without morphological changes. Additionally, comparison analyses (visual SPA assessment and % minimal lumen diameter [MLD] stenosis) among normal pancreas, PAC, and AIP groups were performed using early arterial phase (EAP) reconstructed images.

RESULTS

In 25 (24.8%) AIP cases, marginal irregularities of the SPA were present. The presence of the capsule-like rim and SPV stenosis were significantly associated with the arterial morphological changes. All cases with morphological changes had a capsule-like rim. Visual assessment using EAP reconstructed images revealed irregularities of the SPA in 9 of 38 AIP cases (23.7%); however, arterial narrowing was not detected in any cases. % MLD stenosis in AIP group was significantly lower than that in PAC group (p < 0.0001).

CONCLUSIONS

Although approximately one-quarter of AIP cases potentially demonstrate marginal irregularity in the SPA when it is surrounded by an apparent capsule-like rim, arterial luminal narrowing rarely occurs in contrast to PAC. These arterial findings can help to distinguish AIP from PAC.

MR Imaging of Autoimmune Pancreatitis

Autoimmune pancreatitis (AIP) is characterized by autoimmune inflammatory destruction of the pancreatic tissue. Imaging plays an essential role in the diagnosis. AIP type 1 is the pancreatic manifestation of immunoglobulin G4 (IgG4)-related disease and is associated with IgG4-positive plasma cell infiltration and fibrosis of multiple organ systems. Type 2 is a related disease with pancreatic inflammation with or without concurrent inflammatory bowel disease. The authors demonstrate the imaging findings that are associated with the pancreatic and extra-pancreatic manifestations of AIP. They emphasize the common MR imaging and magnetic resonance cholangiopancreatography findings to help make the diagnosis of AIP.

Abdominal manifestations of IgG4-related disease: a pictorial review

In the last decade, autoimmune pancreatitis has become recognised as part of a wider spectrum of IgG4-related disease, typically associated with elevated serum IgG4 levels and demonstrating a response to corticosteroid therapy. Radiologically, there is imaging overlap with other benign and neoplastic conditions. This pictorial review discusses the intra-abdominal manifestations of this disease on cross-sectional imaging before and after steroid treatment and the main radiological features which help to distinguish it from other key differentials.

TEACHING POINTS

• Autoimmune pancreatitis is part of a spectrum of IgG4-related disease. • Diagnosis is based on raised serum IgG4, clinical, radiological and histopathological findings. • Cross-sectional imaging can demonstrate the typical findings of abdominal IgG4-related disease. • Cross-sectional imaging can be used to monitor response to corticosteroid treatment.

Prediction of pancreatic fistula after pancreatoduodenectomy by preoperative dynamic CT and fecal elastase-1 levels

Objective

To validate preoperative dynamic CT and fecal elastase-1 level in predicting the development of pancreatic fistulae after pancreatoduodenectomy.

Materials and methods

For 146 consecutive patients, CT attenuation values of the nontumorous pancreatic parenchyma were retrospectively measured on precontrast, arterial and equilibrium phase images for calculation of enhancement ratios. CT enhancement ratios and preoperative fecal elastase-1 levels were correlated with the development of pancreatic fistulae using independent t-test, logistic regression models, ROC analysis, Youden method and tree analysis.

Results

The mean value of enhancement ratio on equilibrium phase was significantly higher (p = 0.001) in the patients without pancreatic fistula (n = 107; 2.26±3.63) than in the patients with pancreatic fistula (n = 39; 1.04±0.51); in the logistic regression analyses, it was significant predictor for the development of pancreatic fistulae (odds ratio = 0.243, p = 0.002). The mean preoperative fecal elastase-1 levels were higher (odds ratio = 1.003, p = 0.034) in the pancreatic fistula patients than other patients, but there were no significant differences in the areas under the curve between the prediction values of CT enhancement ratios and fecal elastase-1 combined and those of CT enhancement ratios alone (P = 0.897, p = 0.917) on ROC curve analysis. Tree analysis revealed that the CT enhancement ratio was more powerful predictor of pancreatic fistula than fecal elastase-1 levels.

Conclusion

The preoperative CT enhancement ratio of pancreas acquired at equilibrium phase regardless of combination with fecal elastase-1 levels might be a useful predictor of the risk of developing a pancreatic fistula following pancreatoduodenectomy.

Recent advances in the diagnosis and management of autoimmune pancreatitis

OBJECTIVE

Autoimmune pancreatitis (AIP) is a rare chronic relapsing steroid-responsive fibroinflammatory disorder of the pancreas that is likely caused by immune dysregulation. It is now thought that AIP consists of two distinct clinicopathologic syndromes currently designated as types 1 and 2.

CONCLUSION

A current update on etiopathogenesis, pathology, and clinical and imaging findings of AIP is provided with an emphasis on diagnosis and management.

Mimics of pancreatic ductal adenocarcinoma

Several uncommon primary pancreatic tumors, inflammatory conditions, metastasis to the pancreas and peripancreatic masses can mimic the appearance of pancreatic ductal adenocarcinoma (PDA). Differentiation between these lesions and PDA can be challenging, due to the overlap in imaging features; however, familiarity with their typical imaging features and clinical presentation may be helpful in their differentiation, as in some cases, invasive diagnostic tests or unnecessary surgery can be avoided. The different pathologies that can mimic PDA include inflammatory conditions such as the various forms of pancreatitis (chronic-focal mass-forming, autoimmune and groove pancreatitis), pancreatic neuroendocrine tumors, solid pseudopapillary tumors, metastasis (solid non-lymphomatous and hematologic), congenital variants (annular pancreas), as well as peripancreatic lesions (accessory spleen, adrenal masses, duodenal masses, lymph nodes and vascular lesions), and certain rare pancreatic tumors (e.g., acinar cell tumors, solid serous tumors, hamartoma and solitary fibrous tumors). The clinical presentation and imaging features of the most commonly encountered mimics of PDA are discussed in this presentation with representative illustrations.

Common and less-common renal masses and masslike conditions

As an increasing number of imaging examinations are performed, a greater number of incidental renal lesions are detected. Apart from the usual cysts and solid renal cell carcinomas, a variety of unusual benign and malignant renal lesions exist. Imaging is invaluable in characterizing these lesions and is confirmatory in some benign lesions. Renal cell carcinoma remains the diagnosis of exclusion; however, assessment of the imaging pattern in the appropriate clinical context can improve diagnostic accuracy. The objective of this article is to familiarize the radiologist with the imaging appearance of unusual non-neoplastic and neoplastic lesions and correlate with histopathologic studies when available.

Mass-forming autoimmune pancreatitis and pancreatic carcinoma: differential diagnosis on the basis of computed tomography and magnetic resonance cholangiopancreatography, and diffusion-weighted imaging findings

PURPOSE

To differentiate mass-forming autoimmune pancreatitis (AIP) from pancreatic carcinoma by means of analysis of both computed tomography (CT) and magnetic resonance imaging (MRI) findings.

MATERIALS AND METHODS

Ten patients with mass-forming AIP diagnosed by revised clinical criteria of Japan Pancreas Society and 70 patients with pathologically proven pancreatic carcinoma were enrolled in this retrospective study. Two radiologists independently evaluated the CT and MR imaging findings. The sensitivity, specificity, and odds ratio of significant imaging findings and combinations of findings were calculated.

RESULTS

Seven findings were more frequently observed in AIP patients: (i) early homogeneous good enhancement, (ii) delayed homogeneous good enhancement, (iii) hypoattenuating capsule-like rim, (iv) absence of distal pancreatic atrophy, (v5) duct penetrating sign, (vi) main pancreatic duct (MPD) upstream dilatation ≤ 4 mm, and (vii) an apparent diffusion coefficient (ADC) ≤ 0.88 × 10(-3) mm(2) /s. When the findings of delayed homogeneous enhancement and ADC ≤ 0.88 × 10(-3) mm(2) /s were both used in diagnosis of mass-forming AIP, a sensitivity of 100% and a specificity of 100% were achieved. When 4 of any of the 7 findings were used in the diagnosis of AIP, a sensitivity of 100% and a specificity of 98% were achieved.

CONCLUSION

Analysis of a combination of CT and MR imaging findings allows for highly accurate differentiation between mass-forming AIP and pancreatic carcinoma.

Perfusion computed tomography findings of autoimmune pancreatitis

OBJECTIVES

The aim of this study was to clarify the pancreatic blood perfusion in patients with autoimmune pancreatitis (AIP) and the changes after steroid treatment.

METHODS

Perfusion computed tomography was performed in 11 patients with AIP and 12 control subjects. Pancreatic volumetric blood flow (F(V)), volume of distribution (V(D)), and blood transit time τ were determined from a single-compartment kinetic model. Nine patients with AIP were reexamined by perfusion computed tomography after corticosteroid administration.

RESULTS

The pancreatic F(V) values of the 11 patients with AIP (82.7/min) were significantly lower than those of control subjects (163.5/min, P = 0.0006). On the other hand, the pancreatic V(D) and τ values were not significantly different between AIP and normal. After steroid treatment, the F(V) values of 9 reexamined patients with AIP (76.2/min) were significantly elevated (109.8/min, P = 0.0391). However, the changes of the values after the treatment differed in degree among individuals. The values of 4 patients were dramatically elevated to greater than 100/min, whereas those of 4 other patients did not improve well. The value of the remaining patient whose initial F(V) value was normal (168.09/min) did not change after the treatment.

CONCLUSIONS

Pancreatic volumetric perfusion was attenuated in AIP patients. The perfusion was improved after the steroid treatment.

Morphologic patterns of autoimmune pancreatitis in CT and MRI

BACKGROUND/AIMS

To retrospectively evaluate the morphologic characteristics of autoimmune pancreatitis (AIP) using MRI and CT.

METHODS

86 dynamic contrast-enhanced CT and MRI scans in 36 AIP patients were evaluated regarding: different enlargement types, abnormalities of the main pancreatic duct (MPD), morphology of the parenchyma and other associated findings.

RESULTS

3 types of enlargement were found: (1) a focal type (28%), (2) a diffuse type (involving the entire pancreas, 11%) and (3) a combined type (56%). The MPD was usually dilated together with focal or diffuse narrowing in 67% (24/36). Unenhanced MRI showed AIP area in 56% (mostly T(1) hypo- and T(2) hyperattenuating), and CT in 10% (hypoattenuating). The arterial phase depicted similar patterns for CT and MRI (hypoattenuating in 58 and 52%, respectively). Venous and late venous phase patterns were usually hyperattenuating in MRI (65 and 74%, late enhancement), while CT mostly showed no signal differences (isoattenuating in 57 and 75%), yielding significant differences between CT and MRI for the venous (p < 0.0001) and the late phase (p = 0.025). Miscellaneous findings were: rim sign (25%), pseudocysts (8%) and infiltration of large vessels (11%).

CONCLUSIONS

The 'late-enhancement' sign seems to be a key feature and is best detectable with MRI. MRI may be recommended in the diagnostic workup of AIP patients. and IAP.

Autoimmune pancreatitis: differentiation from pancreatic carcinoma and normal pancreas on the basis of enhancement characteristics at dual-phase CT

OBJECTIVE

The purposes of this study were to define the pancreatic enhancement of autoimmune pancreatitis at dual-phase CT and to compare it with that of pancreatic carcinoma and a normal pancreas.

MATERIALS AND METHODS

Dual-phase CT scans of 101 patients (43 with autoimmune pancreatitis, 13 cases of which were focal; 33 with pancreatic carcinoma, and 25 with a normal pancreas) were evaluated. One radiologist measured the CT attenuation of the pancreatic parenchyma and pancreatic masses in both the pancreatic and hepatic phases of imaging. The mean CT attenuation value of the pancreatic parenchyma in patients with autoimmune pancreatitis was compared with that in patients with a normal pancreas. The mean CT attenuation value of the focal masses in the focal form of autoimmune pancreatitis was compared with that of carcinomas.

RESULTS

In the pancreatic phase, the mean CT attenuation value of the pancreatic parenchyma in patients with autoimmune pancreatitis was significantly lower than that in patients with a normal pancreas (autoimmune pancreatitis, 85 HU; normal pancreas, 104 HU; p < 0.05). In the hepatic phase, however, the mean CT attenuation values were not significantly different (autoimmune pancreatitis, 96 HU; normal pancreas, 89 HU; p = 0.6). In the pancreatic phase, the mean CT attenuation value of the mass in autoimmune pancreatitis was not significantly different from that of carcinoma (autoimmune pancreatitis, 71 HU; carcinoma, 59 HU; p = 0.06), but in the hepatic phase, the value was significantly higher than that of carcinoma (autoimmune pancreatitis, 90 HU; carcinoma, 64 HU; p < 0.001).

CONCLUSION

At dual-phase CT, the enhancement patterns of the pancreas and pancreatic masses in patients with autoimmune pancreatitis are different from those of pancreatic carcinoma and normal pancreas.

Malignant masquerade: dilemmas in diagnosing biliary obstruction

The hepatobiliary surgeon must be as familiar with the nonmalignant processes that can affect the extrahepatic biliary tree as they are with the malignant causes. Subtleties in the patient's history, presentation, and imaging studies may prevent unnecessary extensive hepatobiliary resection. The focus of this article deals with the etiology of nonmalignant obstruction at the biliary bifurcation and hilum and the mid-bile duct. It does not focus on either choledocholithiasis or pancreatitis, the two most common causes of distal bile duct obstruction. Obstruction from pancreatic cancer is also not the focus of this discussion.

Usefulness of serum IgG4 in the diagnosis and follow up of autoimmune pancreatitis: A systematic literature review and meta-analysis

High circulating serum immunoglobulin G4 (IgG4) levels have been proposed as a marker of autoimmune pancreatitis (AIP). The aim of the present study was to review the data existing in the English literature on the usefulness of the IgG4 serum levels in the diagnosis and follow up of patients with AIP. A total of 159 patients with AIP and 1099 controls were described in seven selected papers reporting the usefulness of serum IgG4 in diagnosing AIP. In total, 304 controls had pancreatic cancer, 96 had autoimmune diseases, and the remaining 699 had other conditions. The summary receiver-operating characteristic curve analysis was carried out by means of Meta-DiSc open-access software. Serum IgG4 showed good accuracy in distinguishing between AIP and the overall controls, pancreatic cancer and other autoimmune diseases (area under the curve [+/- SE]: 0.920 +/- 0.073, 0.914 +/- 0.191, and 0.949 +/- 0.024, respectively). The studies analyzed showed significantly heterogeneous specificity values in each of the three analyses performed. The analysis of the four studies comparing AIP and pancreatic cancers also showed significantly heterogeneous values of sensitivities and odds ratios. Regarding the usefulness of IgG4 as a marker of efficacy of steroid treatment, a decrease in the serum concentrations of IgG4 was found in the four available studies. The serum IgG4 subclass is a good marker of AIP, and its determination should be included in the diagnostic workup of this disease. However, the heterogeneity of the studies published until now means that more studies are necessary in order to better evaluate the true accuracy of IgG4 in discriminating AIP versus other autoimmune diseases.

Synchronous autoimmune pancreatitis and infiltrating pancreatic ductal adenocarcinoma: case report and review of the literature

An 80-year-old white man underwent pylorus-preserving pancreaticoduodenectomy after presenting with obstructive jaundice and a dilated biliary tree on cholangiopancreatography. Histologic evaluation of the specimen revealed synchronous autoimmune pancreatitis (lymphoplasmacytic sclerosing pancreatitis) and infiltrating ductal adenocarcinoma of the pancreas. The mixed inflammatory infiltrate centered on the pancreatic ducts was associated with acinar loss, parenchymal fibrosis, and obliterative venulitis. Immunohistochemical labeling with an antibody to IgG4 revealed greater than 50 IgG4-positive plasma cells per high power field. Although not appreciated grossly, pancreatic intraepithelial neoplasia-3 and a neurotropic infiltrating poorly differentiated adenocarcinoma of the pancreas were also present. This case highlights the importance of carefully evaluating patients with autoimmune pancreatitis to rule out an underlying neoplasm and the importance of following those who were treated nonsurgically until the disease fully resolves.

Evaluation of unusual causes of pancreatitis: role of cross-sectional imaging

There are widely diverse causes of pancreatitis. Gallstone and alcohol have been recognized as the most common causes of pancreatitis accounting for 90% of cases. However, acute and chronic pancreatitis may also result from a variety of uncommon causes. The determination of the etiology is important for patient management and prevention of recurrence. Sludge is the most common cause of idiopathic or recurrent acute pancreatitis. Endoscopic ultrasonography is considered as the most accurate diagnostic test for this abnormality. Computed tomography (CT) and magnetic resonance imaging (MRI) have only a limited role in the diagnosis of sludge. However, papillitis observed on the contrast-enhanced CT and MR may provide clues to the detection of pancreatitis secondary to sludge, a small stone or a recently passed stone. Radiological studies, clinical presentation and laboratory data can be helpful in determining the etiology of unusual causes of pancreatitis such as anatomic anomalies, autoimmune pancreatitis, groove pancreatitis, and traumatic pancreatitis.

IgG4-related sclerosing lymphoplasmacytic pancreatitis and cholangitis mimicking carcinoma of pancreas and Klatskin tumour

BACKGROUND

Autoimmune sclerosing pancreatitis is a well-known disease entity for years, particularly recognizing the difficulty in distinguishing it from malignancy. Immunohistochemical study showed that immunoglobulin IgG4 staining was positive in plasma cells of some autoimmune pancreatitis or cholangitis. The term 'autoimmune sclerosing pancreatocholangitis' was used as it was believed that they belonged to a range of disease involving both pancreas and biliary tree. It may also be part of a systemic fibro-inflammatory disease.

PATIENTS AND METHODS

All the patients suffering from immunoglobulin G4 (IgG4)-related pancreatitis and cholangitis from May 2003 to September 2006 in Queen Elizabeth Hospital, Hong Kong were retrospectively studied.

RESULTS

A total of five patients with clinical diagnosis of IgG4-related autoimmune pancreatitis or cholangitis were analysed. All presented with jaundice or abdominal pain, mimicking carcinoma. Two patients had major resection, two patients were diagnosed by intraoperative biopsy and one was based on serum IgG4 level.

CONCLUSION

With the growing awareness of this relatively recently characterized clinical entity and its similar presentation to pancreatic carcinoma or bile duct cholangiocarcinoma, it is important for autoimmune sclerosing pancreatocholangitis to be included in the differential diagnosis of pancreaticobiliary disease. The management strategy has shown to be modified--from major resection to intraoperative biopsy and to the assay of serum IgG4 level without the necessity of histology confirmation.

Dual-phase CT of autoimmune pancreatitis: a multireader study

OBJECTIVE

The purpose of this study was to identify findings that aid in differentiating autoimmune pancreatitis from pancreatic carcinoma using dual-phase CT.

MATERIALS AND METHODS

Dual-phase CT scans of 74 patients (25 with autoimmune pancreatitis, 33 with pancreatic carcinoma, and 16 with a normal pancreas) were independently evaluated by three radiologists for enhancement of the pancreas; the presence of a capsule-like rim, peripancreatic strands, and pancreatic calcifications; pancreatic duct or bile duct changes; and renal involvement. The frequency of CT characteristics was compared between autoimmune pancreatitis and carcinoma. Interobserver agreement for the three reviewers for the assessment of CT characteristics was evaluated using kappa statistics.

RESULTS

Diffusely decreased enhancement of the pancreas (autoimmune pancreatitis vs carcinoma: 28% vs 3%; p = 0.02, kappa = 0.33-0.75), capsule-like rim (40% vs 9%; p = 0.009, kappa = 0.42-0.66), peripancreatic strands (60% vs 27%; p = 0.02, kappa = 0.45-0.54), pancreatic calcifications (32% vs 9%; p = 0.04, kappa = 0.14-0.47), bile duct wall enhancement (52% vs 6%; p = 0.0001, kappa = 0.28-0.47), and renal involvement (28% vs 0%; p = 0.002, kappa = 0.32-0.74) were more frequent in patients with autoimmune pancreatitis. Pancreatic duct dilation (24% vs 67%; p = 0.001, kappa = 0.65-0.73) and abrupt cutoff (16% vs 55%; p = 0.003, kappa = 0.60-0.65) were more frequent in patients with carcinoma.

CONCLUSION

Diffusely decreased enhancement of the pancreas, a capsule-like rim, bile duct enhancement, and renal involvement are useful signs of autoimmune pancreatitis.

Lymphoplasmacytic sclerosing pancreatitis (autoimmune pancreatitis): evaluation with multidetector CT

Lymphoplasmacytic sclerosing pancreatitis is a form of chronic pancreatitis characterized by a mixed inflammatory infiltrate that centers on the pancreatic ducts. It is a cause of benign pancreatic disease that can clinically mimic pancreatic cancer. Preoperative detection of lymphoplasmacytic sclerosing pancreatitis is important because patients usually respond to steroid therapy. Patients with lymphoplasmacytic sclerosing pancreatitis are often referred for computed tomography (CT) when they are suspected of having a pancreatic or biliary neoplasm; therefore, it is important to search for potential findings suggestive of lymphoplasmacytic sclerosing pancreatitis when typical findings of a pancreatic or biliary neoplasm are not found. Typical CT findings include diffuse or focal enlargement of the pancreas without dilatation of the main pancreatic duct. Focal enlargement is most commonly seen in the head of the pancreas, and the involved pancreas on contrast material-enhanced CT images may be iso-attenuating relative to the rest of the pancreas, or hypo-attenuating, especially during the early postcontrast phase. Thickening and contrast enhancement of the wall of the common bile duct and gallbladder may reflect inflammatory infiltrate and fibrosis associated with lymphoplasmacytic sclerosing pancreatitis. There are several features seen at CT that may help to differentiate lymphoplasmacytic sclerosing pancreatitis from pancreatic cancer, such as diffuse enlargement of the pancreas with minimal peripancreatic stranding in patients with obstructive jaundice, an absence of significant pancreatic atrophy, and an absence of significant main pancreatic duct dilatation. When these findings are encountered, clinical, other imaging, and serologic data should be evaluated.

Incidence of the focal type of autoimmune pancreatitis in chronic pancreatitis suspected to be pancreatic carcinoma: experience of a single tertiary cancer center

OBJECTIVE

With an increase in autoimmune pancreatitis (AIP) being reported, the focal type of AIP, which shows localized narrowing of the main pancreatic duct and focal swelling of the pancreas, has recently been recognized. Therefore, cases of focal-type AIP subjected to surgical intervention for presumptive malignancy might previously have been diagnosed as mass-forming chronic pancreatitis. The aim of this study was to elucidate the incidence of focal-type AIP in resected chronic pancreatitis at a single tertiary cancer center. The clinical and radiological features of focal-type AIP were also evaluated.

MATERIAL AND METHODS

We re-evaluated 15 patients who underwent pancreatic resection with a presumed diagnosis of pancreatic ductal adenocarcinoma, and who in the past had been diagnosed pathologically as having chronic pancreatitis.

RESULTS

Seven of 15 patients showed AIP, and the other 8 patients were diagnosed as having mass-forming chronic pancreatitis not otherwise specified by pathological retrospective examination. In other words, nearly half of the cases of resected chronic pancreatitis that were suspected to be pancreatic carcinoma preoperatively showed focal-type AIP. Regarding the characteristic findings of focal-type AIP, narrowing of the pancreatic duct on endoscopic retrograde pancreatography (ERP) might be diagnostic.

CONCLUSIONS

Focal-type AIP is not a rare clinical entity and might be buried in previously resected pancreatic specimens that in the past were diagnosed simply as mass-forming pancreatitis.

CT evaluation of the bulging papilla with endoscopic correlation

A variety of pathologic conditions can cause abnormalities of the ampulla of Vater. A bulging papilla is frequently encountered at computed tomography (CT) and can be seen in healthy individuals as well as in patients with various pathologic conditions such as papillitis, ampullary cancer, and intraductal papillary mucinous tumor. Mural thickening and certain attenuation patterns seen at contrast material-enhanced CT can help differentiate pathologic papilla from normal papilla. Increased targetlike enhancement of the papilla is likely to represent a benign condition such as papillitis, whereas an enhancing polypoid mass or focal asymmetric or irregular thickening with prolonged enhancement in the ampulla of Vater indicates a malignant condition such as ampullary or periampullary carcinoma. Although CT often does not clarify the exact cause of bulging, adequate duodenal distention may allow detection of an abnormal papilla, thereby providing additional information about other abnormalities in the pancreaticobiliary system. Thus, CT findings may prove useful for subsequent imaging studies such as magnetic resonance (MR) cholangiography or endoscopy. MR cholangiography may be equivalent to CT for identifying a bulging papilla and superior for distinguishing the underlying cause. However, endoscopy with or without biopsy is the best method for making a definitive diagnosis in patients with a bulging papilla. Familiarity with the normal imaging anatomy of the periampullary region and with the imaging features of the various pathologic causes of a bulging papilla may be useful in making the diagnosis.

Autoimmune pancreatitis

Background

Approximately 2 per cent of pancreatic masses resected for suspected malignancy are found instead to be a form of chronic pancreatitis defined by a characteristic lymphoplasmacytic infiltrate. This condition is now commonly classified as ‘autoimmune pancreatitis’.

Methods

A literature review of autoimmune pancreatitis was performed using Medline and PubMed. The reference lists of identified articles were searched for further relevant publications.

Results

Patients are predominantly 55-65 years old and present with obstructive jaundice, abdominal pain and weight loss. Imaging may show a mass of malignant appearance or pancreatobiliary tree strictures precipitating surgical exploration. Raised serum levels of IgG4 and specific autoantibodies, when combined with particular radiological features and a biopsy negative for malignancy, enable a preoperative diagnosis and successful treatment with steroids.

Conclusion

Autoimmune pancreatitis is not uncommon and steroid treatment can effect a dramatic improvement. Care is needed to ensure that pancreatic cancer is not misdiagnosed.

Focal lymphoplasmacytic sclerosing pancreatitis: radiological-pathological correlation

OBJECTIVE

To correlate cross-sectional imaging findings with histological results in patients with histopathologically proven lymphoplasmacytic sclerosing pancreatitis (LSP) after surgery.

METHODS

Four cases of resectable pancreatic lesions that were proven to represent LSP are presented in our study. All patients were thought to harbor malignancy. A detailed research in patients' records was retrospectively done concerning clinical presentation and imaging studies.

RESULTS

Characteristic imaging findings consistent with fibrotic changes were evident in only one case on magnetic resonance imaging. A discrete mass was evident on imaging in 2 patients that correlated well with pathology results. In the other patients, the extent of inflammatory changes on microscopic examination correlated well with the degree of pancreatic head enlargement on imaging studies.

CONCLUSIONS

Lymphoplasmacytic sclerosing pancreatitis is a particular form of benign inflammatory pancreatic disease that is extremely difficult to diagnose preoperatively. Familiarization with the variable imaging findings is essential and may result in the reduction of the number of patients with LSP who undergo surgical resection.

Mimicks of pancreatic malignancy in patients with chronic pancreatitis: correlation of computed tomography imaging features with histopathologic findings

Differentiation of chronic pancreatitis and pancreatic carcinoma can be a clinical and radiologic dilemma. Several patients with chronic pancreatitis can undergo unnecessary major abdominal surgery for benign lesions. This pictorial review illustrates the computed tomographic findings and histopathologic features of lesions mimicking pancreatic neoplasm in patients with chronic pancreatitis. Several benign lesions can simulate pancreatic malignancy in patients with chronic pancreatitis. Knowledge of the computed tomographic appearance of these benign entities is important to prevent unnecessary surgeries.

Diagnostic and treatment modalities for autoimmune pancreatitis

Since the recognition of autoimmune pancreatitis (AIP) as a clinical entity, many advances have been made in defining clinical, radiologic, histologic, and laboratory parameters to assist in a complete definition of the disease. Despite all these efforts, a preoperative diagnosis still remains a clinical challenge but is of paramount importance, as these cases have been reported to be steroid-responsive; therefore, early treatment may obviate the need for surgical resection. Although the utilization of recently proposed guidelines by the Japanese Pancreas Society and an Italian study group may further assist the clinician and prompt the initiation of steroid treatment, the response to therapy should be observed within 2 to 4 weeks and reflected in progressive resolution of the presenting radiologic and laboratory abnormalities. Should these fail to demonstrate improvement, the diagnosis of AIP should undergo re-evaluation, and consideration for surgical exploration should be made, as the patient may be harboring a malignancy. Surgical resection in the form of pylorus-preserving pancreaticoduodenectomy remains the optimal solution in the attempt to clarify the diagnosis and offer treatment with low complication rates.

Mass-forming pancreatitis: Value of contrast-enhanced ultrasonography

AIM: To assess the utility of contrast-enhanced ultrasonography (CEUS) with a second-generation contrast medium in the differential diagnosis between mass-forming pancreatitis and pancreatic carcinoma.

METHODS: From our radio-pathology database, we retrieved all the patients affected by mass-forming pancreatitis or pancreatic carcinoma who underwent CEUS. We evaluated the results of CEUS in the study of the 173 pancreatic masses considering the possibilities of a differential diagnosis between mass-forming pancreatitis and pancreatic tumor by identifying the “parenchymographic” enhancement during the dynamic phase of CEUS, which was considered diagnostic for mass-forming pancreatitis.

RESULTS: At CEUS, 94% of the mass-forming pancreatitis showed intralesional parenchymography. CEUS allowed diagnosis of mass-forming pancreatitis with sensitivity of 88.6%, specificity of 97.8%, positive predictive value of 91.2%, negative predictive value of 97.1%, and overall accuracy of 96%. CEUS significantly increased the diagnostic confidence in the differential diagnosis between mass-forming pancreatitis and pancreatic carcinoma, with receiver operating characteristic curve areas from 0.557 (P = 0.1608) for baseline US to 0.956 (P < 0.0001) for CEUS.

CONCLUSION: CEUS allowed diagnosis of mass-forming pancreatitis with diagnostic accuracy of 96%. CEUS significantly increases the diagnostic confidence with respect to basal US in discerning mass-forming pancreatitis from pancreatic neoplasm.

[Isolated or multifocal segmental intrahepatic bile duct dilatation: management]

Segmentary dilatation of intrahepatic bile ducts are well depicted with ultrasound. Two groups of diseases could be differentiated by searching a liver mass: biliary diseases without any tumor or dilatation of biliary duct due to an adjacent liver mass. Inside these two groups, some diseases are frequent and other not. We will emphasize autoimmune cholangitis and (Low Phospholipid Associated Cholelithiasis) LPAC with MDR3 deficiency. Decisional trees are proposed.

L’ictère nu : rôle du radiologue dans la prise en charge diagnostique et thérapeutique

The purpose of this article is to provide an update on imaging techniques for diagnosis and staging of clinical conditions leading to obstructive jaundice. Clinical and imaging findings of the most frequent diseases presenting as obstructive jaundice will be reviewed in order to optimize imaging strategies. Imaging and treatment strategies will be discussed in order to provide an optimal diagnosis and staging with the least invasive techniques in order to minimize complications in these patients.

Mangafodipir trisodium-enhanced MR imaging of pancreatic disease

Our study aimed to assess the diagnostic capabilities of mangafodipir trisodium-enhanced MRI for the evaluation of pancreatic disease. Sixty-three patients suspected of having pancreatic disease underwent MRI with a 1.5-T device. After the acquisition of axial and coronal T2-weighted sequences, the MR protocol included T1-weighted fat-suppressed breath-hold SPGR images obtained before and 30 min after the infusion of Mn-DPDP (Teslascan). The detection of a focal pancreatic lesion and its intensity were evaluated in consensus by two observers, who also attempted to characterize each lesion as benign or malignant. The reviewers were blinded to patient identification and all clinical, laboratory and previous imaging findings. MR imaging results were correlated with surgery (n=37), laparoscopy (n=1), biopsy (n=2) and imaging follow-up (n=22). Sixty-two subjects were effectively included in our analysis because one patient was lost to follow-up; final malignant and benign diagnoses were determined in 22 (35%) and 29 (47%) of the patients, respectively. The level of confidence in the diagnosis of the pancreatic lesion was significantly increased by the administration of Mn-DPDP as demonstrated by ROC analysis of unenhanced and post-contrast image sets (P=0.009). Overall, on the basis of observers' readings, MR assessment of pancreatic disease resulted in 57 correct diagnoses (accuracy, 92%) and five (8%) incorrect diagnoses. The sensitivity, specificity, positive predictive value and negative predictive value of the reviewers for the detection of pancreatic lesions and for the differentiation between benign and malignant masses were 91% (95% CI: 84 and 98%), 93% (95% CI: 86 and 99%), 87% (95% CI: 79 and 95%) and 95% (95% CI: 89 and 100%), respectively. Mn-DPDP-enhanced MRI is an effective diagnostic tool for evaluating pancreatic disease.

Lymphoplasmacytic sclerosing pancreatitis

Lymphoplasmacytic sclerosing pancreatitis is a rare entity that has been described under many different names and constitutes a diagnostic challenge as it may simulate a neoplastic process. Herein, we report a case of a 61-year-old woman who presented to our institution complaining of left flank pain and was found to have normal levels of amylase and lipase. An abdominal magnetic resonance image showed thickening of the pancreatic tail and compression of the pancreatic duct. The radiographic differential included both chronic pancreatitis and a neoplastic process. She underwent an exploratory laparotomy, during which a pancreatectomy and splenectomy were performed. Grossly, the pancreas contained a yellowish white, firm homogeneous mass measuring 6.5 x 3.3 x 2.9 cm involving the entire pancreatic tail and hilum of the spleen. Histologically, pancreatic sections showed extensive fibrosis admixed with an inflammatory infiltrate. This infiltrate was composed mainly of lymphocytes with multiple germinal centers, as well as plasma cells and eosinophils that surrounded pancreatic ducts and extended into the peripancreatic adipose tissue. No malignancy was identified, and the process was diagnosed as lymphoplasmacytic sclerosing pancreatitis.