Prevalence of autoimmune pancreatitis and other benign disorders in pancreatoduodenectomy for presumed malignancy of the pancreatic head

Prevalence of autoimmune pancreatitis in pancreatic resection for suspected malignancy: a systematic review and meta-analysis

BACKGROUND/OBJECTIVES

Autoimmune pancreatitis (AIP) is a diagnosis-challenging disease that often mimics pancreatic malignancy. Pancreatic resection is considered to be a curative treatment for pancreatic ductal adenocarcinoma (PDAC). This meta-analysis aims to study the incidence of AIP in patients who have undergone pancreatic resection for clinical manifestation of cancer.

METHODS

A comprehensive search was conducted in three databases, PubMed, Embase and the Cochrane Library, using the terms 'autoimmune pancreatitis' and 'pancreatic resection' and supplemented by manual checks of reference lists in all retrieved articles.

RESULTS

Ten articles were included in the final analysis. 8917 pancreatic resections were performed because of a clinical suspicion of pancreatic cancer. AIP accounted for 140 cases (1.6%). Type 1 AIP comprised the majority of cases, representing 94% (132 cases), while type 2 AIP made up the remaining 6% (eight cases) after further classification. AIP accounted for almost 26% of all cases of benign diseases involving unnecessary surgery and was overrepresented in males in 70% of cases compared to 30% in females. The mean age for AIP patients was 59 years. Serum CA 19 - 9 levels were elevated in 23 out of 47 (49%) AIP patients, where higher levels were detected more frequently in patients with type 1 AIP (51%, 22 out of 43) than in those with type 2 AIP (25%, 1 out of 4). The sensitivity of IgG4 levels in type 1 AIP was low (43%, 21/49 patients).

CONCLUSION

Even with modern diagnostic methods, distinguishing between AIP and PDAC can still be challenging, thus potentially resulting in unnecessary surgical procedures in some cases. Serum CA 19 - 9 levels are not useful in distinguishing between AIP and PDAC. Work must thus be done to improve diagnostic methods and avoid unnecessary complicated surgery.

Investigating misdiagnosis of suspected cancer among patients undergoing pancreatoduodenectomy: three decades of experience

BACKGROUND

Diagnostic error can result in pancreatoduodenectomy (PD) being mistakenly performed for benign disease. The aims of this study were to observe the error rate in PD over three decades and identify characteristics of benign disease that can mimic malignancy.

METHODS

Patients with a benign histological diagnosis after having PD performed for suspected malignancy between 1988 and 2019 were selected for review. Preoperative clinical features, imaging and pathological samples were reviewed alongside resection specimens to identify features that may have led to misdiagnosis.

RESULTS

Over the study period, 1812 patients underwent PD for suspected malignancy and 97 (5.2 %) of these had a final benign diagnosis. The rate of benign cases reduced across the study period. Some 62 patients proceeded to surgery without a preoperative tissue diagnosis; the decision to operate was made upon clinical and radiologic features alone. There were six patients who had a preoperative pathological sample suspicious for malignancy, of which two had autoimmune pancreatitis in the postoperative histology specimen.

DISCUSSION

Benign conditions, notably autoimmune and chronic pancreatitis, can mimic malignancy even with the use of EUS-FNA. The results of all available diagnostic modalities should be interpreted by a multidisciplinary team and honest discussions with the patient should follow.

Main Diagnostic Criteria Usually Does Not Work for Autoimmune Pancreatitis Wrongly Presuming Malignancy

Background

Autoimmune pancreatitis (AIP) usually responds dramatically to steroid therapy. Occasionally, however, misdiagnosed patients have undergone pancreaticoduodenectomy. This study is aimed at providing useful information to improve the accuracy of diagnosis before surgery and thus avoid unnecessary resections in patients with AIP.

Methods

From January 2015 to February 2020, a series of patients were enrolled, having undergone pancreaticoduodenectomy for presumed malignancy. AIP diagnoses were confirmed by postoperative pathology. The demographic and clinical data of the AIP patients were evaluated. The main diagnostic criteria (HISORt, Asian, and ICDC) for AIP were applied to assess whether and how unnecessary surgery could have been avoided.

Results

A total of 124 cases of pancreaticoduodenectomy were performed for presumed malignancy. Six patients were diagnosed with benign disease and five with AIP. The prevalences of benign disease and AIP were 4.8% and 4%, respectively. Four patients were female and 1 male, with a mean age of 60.0 years old. Jaundice, pain, and weight loss were observed in 100%, 20%, and 40% of AIP patients, respectively. The radiologic features of the AIP patients were a diffusely enlarged gland (40.0%), a focally enlarged gland (40.0%), pancreatic ductal dilatation (60.0%), upstream parenchymal atrophy (20.0%), bile duct thickening (66.0%), and bile duct stricture (40.0%). Based on the diagnostic criteria for AIP, surgery could have been avoided in two cases.

Conclusions

IgG4 measurement and integrated use of major diagnostic criteria should be emphasized in every patient eligible for pancreaticoduodenectomies.

Serum cytokine profiles in patients with pancreatic cancer and chronic pancreatitis

BACKGROUND

Chronic pancreatitis (CP) may cause tumor-like lesions, creating a challenge in distinguishing between CP and pancreatic ductal adenocarcinoma (PDAC) in a patient. Given that invasive surgery is a standard cancer treatment, we aimed to examine whether a noninvasive diagnostic tool utilizing serum cytokines could safely differentiate between PDAC and CP.

METHODS

A pre-operative serum panel comprising 48 inflammatory cytokines, CA19-9, and C-reactive protein (CRP) was analyzed, consisting of 231 patients, 186 with stage I-III PDAC and 45 with CP. We excluded PDAC patients who underwent neoadjuvant therapy and those CP patients with other active malignancies. The laboratory variables most associated with PDAC diagnosis were assessed using logistic regression and selected using the lasso method.

RESULTS

The cytokines CTACK, GRO-α, and β-NGF were selected alongside CA19-9 and CRP for our differential diagnostic model. The area under the curve (AUC) for our differential diagnostic model was 0.809 (95% confidence interval [CI] 0.738-0.880), compared with 0.791 (95% CI 0.728-0.854) for CA19-9 alone (not significant).

CONCLUSIONS

We found that inflammatory cytokines CTACK, GRO-α, and β-NGF alongside CA19-9 and CRP may help distinguish PDAC from CP.

Clinicopathological study of surgically treated non-neoplastic diseases of the pancreas with special reference to autoimmune pancreatitis

PURPOSE

After the popularization of serum immunoglobulin G4 (IgG4) measurement and endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) in our institute, surgical resection for non-neoplastic diseases of the pancreas became less common. Although the incidence of such false-positive cases was clarified in the 10-year period after the introduction of these measures (2009-2018), these data were not compared with the 30 years before 2009 (1979-2008). This study was performed to determine the percentage of autoimmune pancreatitis (AIP) that was included during the latter period and how the numbers of false-positive cases differed between the two periods.

METHODS

From 1979 to 2008, 51 patients had clinical suspicion of pancreatic carcinoma (false-positive disease). Among these 51 patients, 32 non-alcoholic patients who had tumor-forming chronic pancreatitis (TFCP) were clinically, histologically, and immunohistochemically compared with 11 patients who had TFCP during the latter 10-year period.

RESULTS

Retrospective IgG4 immunostaining of false-positive TFCP revealed 14 (35.0%) cases of AIP in the former 30 years versus 5 (45.5%) in the latter 10 years. There were 40 (5.9%) cases of TFCP among 675 patients in the former 30 years and 11 (0.9%) among 1289 patients in the latter 10 years.

CONCLUSIONS

When the TFCP ratio of pancreatic resections and the AIP ratio of false-positive TFCPs were compared between the two periods, the TFCP ratio was 5.9% versus 0.9% and the AIP ratio was 35.0% versus 45.5%, respectively. It can thus be speculated that IgG4 measurement and EUS-FNA are absolutely imperative for the diagnosis of TFCP.

The Rate of Avoidable Pancreatic Resections at a High-Volume Center: An Internal Quality Control and Critical Review

BACKGROUND

The incidence of benign diseases among pancreatic resections for suspected malignancy still represents a relevant issue in the surgical practice. This study aims to identify the preoperative pitfalls that led to unnecessary surgeries at a single Austrian center over a twenty-year period.

METHODS

Patients undergoing surgery for suspected pancreatic/periampullary malignancy between 2000 and 2019 at the Linz Elisabethinen Hospital were included. The rate of "mismatches" between clinical suspicion and histology was considered as primary outcome. All cases that, despite that, fulfilled the indication criteria for surgery were defined as minor mismatches (MIN-M). Conversely, the true avoidable surgeries were identified as major mismatches (MAJ-M).

RESULTS

Among the 320 included patients, 13 (4%) presented with benign lesions at definitive pathology. The rate of MAJ-M was 2.8% (n = 9), and the most frequent causes of misdiagnoses were autoimmune pancreatitis (n = 4) and intrapancreatic accessory spleen (n = 2). In all MAJ-M cases, various mistakes within the preoperative workup were detected: lack of multidisciplinary discussion (n = 7, 77.8%); inappropriate imaging (n = 4, 44.4%); lack of specific blood markers (n = 7, 77.8%). The morbidity and mortality rates for mismatches were 46.7% and 0.

CONCLUSION

All avoidable surgeries were the result of an incomplete pre-operative workup. The adequate identification of the underlying pitfalls could lead to minimize and, potentially, overcome this phenomenon with a concrete optimization of the surgical-care process.

Is Surgery in Autoimmune Pancreatitis Always a Failure?

Autoimmune pancreatitis is a rare form of chronic pancreatitis of presumed autoimmune etiology. Due to significant overlap in clinical and imaging characteristics, misdiagnosis as a pancreatic malignancy is common. As a result, a significant number of patients undergo a major pancreatic resection, associated with considerable morbidity, for a disease process that generally responds well to corticosteroid therapy. In the past ten years, important advances have been made in understanding the disease. Several diagnostic criteria have been developed to aid in diagnosis. Despite this, pancreatic resection may still be required in a subset of patients to reliably exclude pancreatic malignancy and establish a definite diagnosis of autoimmune pancreatitis. This article aimed to define the role of surgery in autoimmune pancreatitis, if any. For this purpose, published case series of patients with a diagnosis of autoimmune pancreatitis, based on the histopathological examination of surgical specimens, were reviewed and patients' clinical, radiological and serological details were assessed. At the end, histopathologic examinations of patients who underwent pancreatic resection at our department in the last 10 years were retrospectively reviewed in order to identify patients with autoimmune pancreatitis and assess their clinical characteristics.

Steroid treatment response combined with serological mark in differentiating type-1 autoimmune pancreatitis from pancreatic cancer

Autoimmune pancreatitis (AIP) and pancreatic cancer (PC) are two different diseases. Their diagnosis, treatment, and prognosis are different, and it is difficult to differentiate them. This study aimed to explore the role of steroid treatment response combined with serological mark in distinguishing type-1 AIP from PC. Clinical data were collected and compared from 50 cases of AIP (group 1) and 100 cases of PC (group 2). The diagnostic value of serum IgG4, CA19-9, globulin, and eosinophil cell (EC) were evaluated. The response of steroid treatment of 28 patients with atypical imaging in group 1 was analyzed. After 2 weeks, the patients were classified as positive and negative steroid response according to the manifestations and/or the radiological changes. The positive response cases (n = 20) were confirmed as AIP, whereas negative ones (n = 8) were finally diagnosed as PC after complete resection. Serum globulin, IgG4, and EC levels in group 1 were significantly higher than those in group 2 (P < .01), and CA19-9 levels were distinctly lower in group 1 (P < .01). The level of serum IgG4 was related to the accuracy of diagnosis of AIP on the basis of the result of logistic regression analysis. Two-weeks steroid therapy response combined with serum IgG4 levels contribute to the differential diagnosis AIP and PC. However, regular and long-term follow-up were important for the differential diagnosis. There was an urgent need to explore the specific markers that distinguish these 2 entities.

The Clinical Utility of Soluble Serum Biomarkers in Autoimmune Pancreatitis: A Systematic Review

Autoimmune pancreatitis (AIP) is a rare etiological type of chronic pancreatitis. The clinical and radiological presentation of AIP often resembles that of pancreatic cancer. Identifying non-invasive markers for their early distinction is of utmost importance to avoid unnecessary surgery or a delay in steroid therapy. Thus, this systematic review was conducted to revisit all current evidence on the clinical utility of different serum biomarkers in diagnosing AIP, distinguishing AIP from pancreatic cancer, and predicting disease course, steroid therapy response, and relapse. A systematic review was performed for articles published up to August 2021 by searching electronic databases such as MEDLINE, Web of Science, and EMBASE. Among 5123 identified records, 92 studies were included in the qualitative synthesis. Apart from immunoglobulin (Ig) G4, which was by far the most studied biomarker, we identified autoantibodies against the following: lactoferrin, carboanhydrase II, plasminogen-binding protein, amylase-α2A, cationic (PRSS1) and anionic (PRSS2) trypsinogens, pancreatic secretory trypsin inhibitor (PSTI/SPINK1), and type IV collagen. The identified novel autoantigens were laminin 511, annexin A11, HSP-10, and prohibitin. Other biomarkers included cytokines, decreased complement levels, circulating immune complexes, N-glycan profile changes, aberrant miRNAs expression, decreased IgA and IgM levels, increased IgE levels and/or peripheral eosinophil count, and changes in apolipoprotein isoforms levels. To our knowledge, this is the first systematic review that addresses biomarkers in AIP. Evolving research has recognized numerous biomarkers that could help elucidate the pathophysiological mechanisms of AIP, bringing us closer to AIP diagnosis and its preoperative distinction from pancreatic cancer.

Early detection of pancreatic tumors by advanced EUS imaging

The early detection of pancreatic ductal adenocarcinoma (PDAC) dramatically improves outcome. All available state-of-the-art imaging methods allow early detection with EUS being the best technique for exclusion of PDAC and detection of very early PDAC. Etiological differentiation of small SPL is important to guide individually tailored patients' management including radical surgery in resectable PDAC, medical (neoadjuvant or palliative intended) treatment in patients with non-resectable malignancy, pancreatic parenchyma saving strategies in some non-PDAC, and follow-up in particular in low-grade PanNEN or other small benign lesions. Multimodality EUS imaging including B-Mode assessment, elastography, contrast-enhancement and EUS-guided sampling is the most appropriate technique for diagnosis and risk assessment of small SPL. We present a review discussing modern (endoscopic) ultrasound imaging techniques including contrast enhanced ultrasound and elastography for the early detection and characterization of solid pancreatic lesions.

Preoperative biopsy for suspected adenocarcinoma of the pancreatic head: yield and complications

BACKGROUND

Histologic confirmation before pancreaticoduodenectomy (PD) for suspected pancreatic cancer is often performed. We assessed the yield of preoperative biopsy in these patients considering the associated complications.

METHODS

We retrospectively evaluated 216 patients that underwent PD for suspected carcinoma (CA) between 2012 and 2018. Post procedure complications and delay in surgery were assessed, as well as the postoperative diagnosis in relation to preoperative parameters.

RESULTS

Preoperative biopsy was performed in 142 patients (65.7%). Pathologic findings suggestive of CA were found in 106 (74.6%), while benign histology was found in 23 (16.1%), and non-diagnostic findings in 12 (8.4%). Seventy-four patients (34.3%) were operated without a preoperative biopsy. The time from diagnosis to surgery was significantly prolonged in those that underwent biopsy compared to patients that were taken straight to surgery (40±14 versus 18±15 days, P<0.001), and 18 patients (12.6%) suffered from clinically significant post procedure complications. Patients with a preoperative biopsy suggestive of CA, and those that were operated without a preoperative histologic confirmation had comparable rates of CA as a final pathological diagnosis (95.2% and 94.5%, respectively). Nevertheless, in patients with a benign or a non-diagnostic biopsy, the rates of pathologic diagnosis of CA were 69.6% and 73.6% respectively. Elevated levels of CA19-9 and a positive preoperative biopsy were associated with a final pathology of CA.

CONCLUSIONS

Preoperative histology is not uniformly required in patients with suspected pancreatic cancer. If preoperative biopsy is performed, benign histology does not rule out cancer but warrants additional evaluation prior to surgery.

The Role of IgG4 in Autoimmunity and Rheumatic Diseases

The distinguishing of the IgG4-related disease (IgG4-RD) from among other rheumatic diseases has brought attention to the IgG4 subclass of immunoglobulins. It is the least numerous subclass among immunoglobulins G. In general, IgG4 is considered to be non-inflammatory and tolerance inducing, due to its unique structure. However, in IgG4-RD this antibody plays a pathogenic role in activation of the fibrinogenesis and of the inflammatory process; there are also suggestions that it may be a marker of an abnormal inflammatory response. The importance of IgG4 for the pathogenesis of allergic diseases, with a vital role of its ratio to immunoglobulin E (IgE/IgG4 ratio), has been known for years. The role of IgG4 in the course and pathogenesis of rheumatic diseases is still being researched and is not yet fully understood. Increased IgG4 levels have been revealed in rheumatoid arthritis, although no clear link between this phenomenon and disease activity has been demonstrated. There are articles on the potential importance of IgG4 concentration (of both elevated and decreased serum levels) in Sjogren’s syndrome. Additionally, anti-nuclear IgG4 antibody significant titers have been detected in SLE patients, and it has been suggested that the effect of these antibodies on complement consumption and the production of proinflammatory cytokines may play a role in inhibiting the progression of SLE. IgG4 plays a role in autoimmune diseases other than rheumatic diseases, such as pemphigus, bullous pemphigoid, idiopathic membranous glomerulonephritis, or myasthenia gravis, but also in helmints infections. Research shows the importance of IgG4 in malignancy of neoplasms. Melanoma cells are known to stimulate IgG4 production through a modified Th2-based inflammatory response. The role of this immunoglobulin in cholangiocarcinoma is also considered as possible. The aim of this review article is to discuss the current knowledge of IgG4 not only from the perspective of the IgG4-RD but also from a point of view of other autoimmune diseases with particular emphasis on rheumatic diseases.

Evolving pancreatic cancer treatment: From diagnosis to healthcare management

The prognosis of pancreatic ductal adenocarcinoma is still the worst among solid tumors. In this review, a panel of experts addressed the main unanswered questions about the clinical management of this disease, with the aim of providing practical decision support for physicians. On the basis of the evidence available from the literature, the main topics concerning pancreatic cancer are discussed: the diagnosis, as the need for a pathological characterization and the role for germ-line and somatic molecular profiling; the therapeutic management of resectable disease, as the role of upfront surgery or neoadjuvant chemotherapy, the post-operative restaging and the optimal timing foradjuvant chemotherapy, the management of the borderline resectable and locally advanced disease; the metastatic disease and the role of surgery for the management of patients with isolated metastasis and the use of biomarkers of metastatic potential; the role of supportive care and the healthcare management of pancreatic ductal adenocarcinoma.

Imaging diagnosis of autoimmune pancreatitis using endoscopic ultrasonography

The diagnosis of autoimmune pancreatitis (AIP) is challenging and should be achieved through the comprehensive evaluation of clinical, radiological, serological, and pathological evidence, as there is currently no single reliable diagnostic modality. Endoscopic ultrasonography (EUS) can reveal pancreatic parenchymal and ductal features in much more detail than any other existing imaging modality. In this article, we focused on three applications of EUS, i.e., conventional EUS imaging, EUS elastography (EUS-EG), and contrast-enhanced harmonic EUS (CEH-EUS), for the diagnosis of AIP. Diffuse hypoechoic areas, diffuse enlargement, bile duct wall thickening, and peripancreatic hypoechoic margins on conventional EUS are characteristic features of AIP, and the frequencies of these findings are significantly higher in AIP than in pancreatic cancer (PC). EUS-EG of the pancreatic parenchyma in AIP showed homogenous stiffness and that the elasticity of the pancreas may change after steroid therapy. CEH-EUS revealed focal or diffuse iso-enhancement in most AIP cases and hypo-enhancement in most PC cases. However, some AIP cases show a contrast enhancement pattern similar to that of PC. It should be noted that EUS findings of AIP may differ depending on its stage or disease activity. Differentiation from PC has become an increasingly important issue in the process of diagnosing AIP, and EUS, including elastography and contrast enhancement, could be a promising imaging modality for this purpose.

Endoscopic ultrasound (EUS) and the management of pancreatic cancer

Pancreatic cancer is one of the leading causes of cancer-related mortality in western countries. Early diagnosis of pancreatic cancers plays a key role in the management by identification of patients who are surgical candidates. The advancement in the radiological imaging and interventional endoscopy (including endoscopic ultrasound (EUS), endoscopic retrograde cholangiopancreatography and endoscopic enteral stenting techniques) has a significant impact in the diagnostic evaluation, staging and treatment of pancreatic cancer. The multidisciplinary involvement of radiology, gastroenterology, medical oncology and surgical oncology is central to the management of patients with pancreatic cancers. This review aims to highlight the diagnostic and therapeutic role of EUS in the management of patients with pancreatic malignancy, especially pancreatic ductal adenocarcinoma.

Current controversies and advances in the management of pancreatic adenocarcinoma

Pancreatic adenocarcinoma is a lethal disease with a mortality rate that has not significantly improved over decades. This is likely due to several challenges unique to pancreatic cancer. Most patients with pancreatic cancer are diagnosed at a late stage of disease due to the lack of specific symptoms prompting an early investigation. A small subset of patients who are diagnosed at an early stage have a better chance at survival with curative surgical resection, but most patients still succumb to the disease in a few years. The dismal overall prognosis is due to suspected micro-metastasis at an early stage. Due to this reason, there is a recent interest in treating all patients with pancreatic cancers with systemic therapy upfront (including the ones that are surgically resectable). This approach is still not the standard of care due to the lack of robust prospective data available. Recent advancements in treatment regimens of chemotherapy, radiation and immunotherapy have improved the overall short-term survival but the long-term survival still remains poor. Novel approaches in diagnosis and treatment have shown promise in clinical studies but long-term clinical data is lacking. The following manuscript presents an overview of the epidemiology, diagnosis, staging, recent advances, novel approaches and controversies in the management of pancreatic adenocarcinoma.

Curing pancreatic cancer

The distinct biology of pancreatic cancer with aggressive and early invasive tumor cells, a tumor promoting microenvironment, late diagnosis, and high therapy resistance poses major challenges on clinicians, researchers, and patients. In current clinical practice, a curative approach for pancreatic cancer can only be offered to a minority of patients and even for those patients, the long-term outcome is grim. This bitter combination will eventually let pancreatic cancer rise to the second leading cause of cancer-related mortalities. With surgery being the only curative option, complete tumor resection still remains the center of pancreatic cancer treatment. In recent years, new developments in neoadjuvant and adjuvant treatment have emerged. Together with improved perioperative care including complication management, an increasing number of patients have become eligible for tumor resection. Basic research aims to further increase these numbers by new methods of early detection, better tumor modelling and personalized treatment options. This review aims to summarize the current knowledge on clinical and biologic features, surgical and non-surgical treatment options, and the improved collaboration of clinicians and basic researchers in pancreatic cancer that will hopefully result in more successful ways of curing pancreatic cancer.

Comparison of clinical usefulness of serum Ca125 and CA19-9 in pancreatic adenocarcinoma diagnosis: meta-analysis and systematic review of literature

INTRODUCTION

Pancreatic adenocarcinoma remains one of the most lethal cancers. The only recommended biomarker CA19-9 proves to be not accurate enough to establish a certain diagnosis. Therefore, a determination of usefulness of other biomarkers is essential. Our aim was to compare the specificity and sensitivity of Ca125 and CA19-9 by means of meta-analysis. The systematic review of combined tests (CA19-9 + Ca125) was also performed.

METHODS

We conducted a systematic search of Medline (via PubMed) and Ovid. After screening of abstracts and the assessment of full-texts, nine studies (number of patients, n = 1599) were included. Hierarchical summary receiver under operator curve (hsROC) model was applied to estimate the diagnostic accuracy.

RESULTS

CA19-9 sensitivity and specificity were 0.748 (95%CI 0.676-0.809) and 0.782 (95%CI 0.716-0.836), respectively. These values were estimated on 0.593 (95%CI 0.489-0.69) and 0.754 (95%CI 0.817-0.668) for Ca125. Regarding the heterogeneity of studies, a strong threshold effect for Ca125 and moderate one for CA19-9 were found.

CONCLUSIONS

Our meta-analysis did not prove the superiority of Ca125. It should be nevertheless noted that the sparsity of studies precludes accurate analysis of various factors' influence. The review of proposed combined tests shows that CA19-9 + Ca125 models are generally characterized by higher sensitivity.

Deep Convolutional Neural Network-Assisted Feature Extraction for Diagnostic Discrimination and Feature Visualization in Pancreatic Ductal Adenocarcinoma (PDAC) versus Autoimmune Pancreatitis (AIP)

The differentiation of autoimmune pancreatitis (AIP) and pancreatic ductal adenocarcinoma (PDAC) poses a relevant diagnostic challenge and can lead to misdiagnosis and consequently poor patient outcome. Recent studies have shown that radiomics-based models can achieve high sensitivity and specificity in predicting both entities. However, radiomic features can only capture low level representations of the input image. In contrast, convolutional neural networks (CNNs) can learn and extract more complex representations which have been used for image classification to great success. In our retrospective observational study, we performed a deep learning-based feature extraction using CT-scans of both entities and compared the predictive value against traditional radiomic features. In total, 86 patients, 44 with AIP and 42 with PDACs, were analyzed. Whole pancreas segmentation was automatically performed on CT-scans during the portal venous phase. The segmentation masks were manually checked and corrected if necessary. In total, 1411 radiomic features were extracted using PyRadiomics and 256 features (deep features) were extracted using an intermediate layer of a convolutional neural network (CNN). After feature selection and normalization, an extremely randomized trees algorithm was trained and tested using a two-fold shuffle-split cross-validation with a test sample of 20% (n = 18) to discriminate between AIP or PDAC. Feature maps were plotted and visual difference was noted. The machine learning (ML) model achieved a sensitivity, specificity, and ROC-AUC of 0.89 ± 0.11, 0.83 ± 0.06, and 0.90 ± 0.02 for the deep features and 0.72 ± 0.11, 0.78 ± 0.06, and 0.80 ± 0.01 for the radiomic features. Visualization of feature maps indicated different activation patterns for AIP and PDAC. We successfully trained a machine learning model using deep feature extraction from CT-images to differentiate between AIP and PDAC. In comparison to traditional radiomic features, deep features achieved a higher sensitivity, specificity, and ROC-AUC. Visualization of deep features could further improve the diagnostic accuracy of non-invasive differentiation of AIP and PDAC.

Utility of endoscopic ultrasound-guided fine-needle biopsy in the diagnosis of type 1 autoimmune pancreatitis

Background and study aims  Endoscopic ultrasound (EUS)-guided fine-needle aspiration (FNA) performs poorly in the histological diagnosis of type 1 autoimmune pancreatitis (AIP). The aim of this study was to assess the performance of fine-needle biopsy (FNB) comparing reverse bevel (RB) and fork-tip (FT) needles. Patients and methods  A retrospective study of prospectively maintained databases was performed. Patients with a final diagnosis of type 1 AIP who underwent EUS-FNB during diagnostic workup were included. Pathology reports were reviewed and classified as per international consensus diagnostic criteria (ICDC). The Primary outcome was EUS-FNB sensitivity in diagnosing type 1 AIP. Results  Between March 2011 and December 2018, 24 patients with a final diagnosis of type 1 AIP underwent FNB. Six patients underwent biopsy with the RB needle and 18 with the FT needle. Mean age (± SD) 62.2 (± 11.4), 17 (70.8 %) male. No RB samples were diagnostic compared to 14 (78 %) FT; P  = 0.001; of which 13 (72 %) were level 1. In eight (44 %) of FT cases a diagnosis was not possible without histology. Initial biopsy was diagnostic in five (62.5 %) of these cases. Including repeat biopsy, seven (87 %) had a diagnosis made by FT needle. Obliterative phlebitis (44 %) was the least frequently identified pathological feature and immunoglobulin (IgG)4 + plasma cells > 10 per high power field (78 %) the most common. Conclusion  The FT needle demonstrated good performance for diagnosing type 1 AIP. The results support the preferential use of this core biopsy needle for EUS pancreatic tissue sampling.

Usefulness of endoscopic ultrasound-guided fine-needle biopsy for the diagnosis of autoimmune pancreatitis using a 22-gauge Franseen needle: a prospective multicenter study

BACKGROUND

Detailed histological evaluation is important in the diagnosis of autoimmune pancreatitis (AIP). However, it remains challenging to obtain adequate tissue from the pancreas. Recently, several reports have suggested the usefulness of endoscopic ultrasound-guided fine-needle biopsy (EUS-FNB) using the new "core" needles for acquiring pancreatic tissue. We aimed to investigate the usefulness of EUS-FNB for diagnosing AIP with one such needle, a 22-gauge Franseen needle.

METHODS

Patients who met the imaging diagnostic criteria for AIP based on the International Consensus Diagnostic Criteria (ICDC) were enrolled in the study. All patients underwent EUS-FNB with a 22-gauge Franseen needle. Histological findings were evaluated based on the ICDC, and the detection rates of level 1 and level 1 or 2 histology were calculated.

RESULTS

56 patients from 11 different institutions were enrolled in the final analysis (55 suspected to have type 1 AIP and one with type 2 AIP). Lymphoplasmacytic infiltration, obliterative phlebitis, storiform fibrosis, and > 10 IgG4-positive cells per high-power field were detected in 55 (100 %), 24 (43.6 %), 40 (72.7 %), and 36 (65.5 %) of the 55 patients, respectively. The detection rates of level 1 and level 1 or 2 histology for AIP were 58.2 % (95 % confidence interval [CI] 44.1 % - 71.3 %) and 92.7 % (95 %CI 82.4 % - 98.0 %), respectively, which were apparently higher than our historical results (7.9 % [95 %CI 1.7 % - 21.4 %] and 62.2 % [95 %CI 46.5 % - 76.2 %], respectively) using a conventional needle.

CONCLUSIONS

EUS-FNB with a 22-gauge Franseen needle demonstrated favorable detection rates which would be clinically beneficial for the histological diagnosis of AIP.

Differentiation of Focal-Type Autoimmune Pancreatitis From Pancreatic Ductal Adenocarcinoma Using Radiomics Based on Multiphasic Computed Tomography

OBJECTIVES

The aim of this study was to develop a radiomics model for a differential diagnosis of focal-type autoimmune pancreatitis (AIP) from pancreatic ductal adenocarcinoma.

METHODS

A total of 96 patients, 45 with AIP and 51 with pancreatic ductal adenocarcinoma, were retrospectively evaluated. All patients underwent pretreatment abdominal computed tomography imaging acquired at noncontrast, arterial, and venous phases. Furthermore, 1160 radiomics features were extracted from each phasic image to build radiomics models. The performance of radiomics model was evaluated by sensitivity, specificity, and accuracy. The results of radiomics model were also compared with those of radiologists' visual assessments.

RESULTS

The sensitivity, specificity, and accuracy of the optimal radiomics model were 93.3%, 96.1%, and 94.8%, respectively. They were higher than those of the radiologists' assessments with sensitivity of 57.78% and 73.33%, specificity of 88.24% and 90.20%, and accuracy of 75.00% and 81.25%, respectively.

CONCLUSION

Radiomics is helpful for a differential diagnosis of AIP in clinical practice as a noninvasive and quantitative method.

European Guideline on IgG4-related digestive disease - UEG and SGF evidence-based recommendations

The overall objective of these guidelines is to provide evidence-based recommendations for the diagnosis and management of immunoglobulin G4 (IgG4)-related digestive disease in adults and children. IgG4-related digestive disease can be diagnosed only with a comprehensive work-up that includes histology, organ morphology at imaging, serology, search for other organ involvement, and response to glucocorticoid treatment. Indications for treatment are symptomatic patients with obstructive jaundice, abdominal pain, posterior pancreatic pain, and involvement of extra-pancreatic digestive organs, including IgG4-related cholangitis. Treatment with glucocorticoids should be weight-based and initiated at a dose of 0.6-0.8 mg/kg body weight/day orally (typical starting dose 30-40 mg/day prednisone equivalent) for 1 month to induce remission and then be tapered within two additional months. Response to initial treatment should be assessed at week 2-4 with clinical, biochemical and morphological markers. Maintenance treatment with glucocorticoids should be considered in multi-organ disease or history of relapse. If there is no change in disease activity and burden within 3 months, the diagnosis should be reconsidered. If the disease relapsed during the 3 months of treatment, immunosuppressive drugs should be added.

Pancreatic and biliary tract involvement in IgG4-related disease

The diagnosis and treatment of pancreatic and biliary tract involvement in IgG4 disease can be challenging for physicians. A French series shows that the pancreas is the most frequently involved organ in systemic IgG4 disease. Pancreatitis may be found in more than 50% of patients with IgG4 disease and the biliary tract is involved in one third. Pancreatic or biliary involvement may be isolated, metachronous or synchronous of other IgG4-related organ injuries. Pancreatitis related to IgG4 disease is called autoimmune pancreatitis (AIP) type 1. The diagnosis is mainly suspected in the presence of symptoms and morphological features. Changes observed on conventional imaging are not typical and are usually similar to lesions observed in autoimmune pancreatitis type 2. AIP type 1 can also sometimes have a clinical or morphological presentation that mimics pancreatic cancer, especially pseudo-tumoral forms, associated with obstructive jaundice, weight loss and fatigue. Thus, the first challenge is to confirm the diagnosis of autoimmune pancreatitis and to exclude cancer. The AIP type must then be determined to decide on the most appropriate treatment.

Modern ultrasound imaging of pancreatic tumors

In patients with solid pancreatic lesions (SPLs), the differential diagnosis must be evaluated to determine whether radical surgery, pancreatic parenchyma-saving strategies, or follow-up is indicated. Contrast-enhanced (endoscopic) ultrasonography and elastography facilitate the further characterization of SPLs. The majority of cases of pancreatic ductal adenocarcinoma exhibit hypoenhancement with contrast-enhanced ultrasonography. Elastographically soft SPLs are benign with very few exceptions, whereas stiffer SPLs can be malignant or benign. This article reviews the current use of modern ultrasound imaging techniques, including contrast-enhanced ultrasonography and elastography, for the detection and characterization of SPLs. In particular, the unexcelled diagnostic potential of multiparametric endoscopic ultrasonography to detect and characterize small SPLs is highlighted.

Endoscopic Ultrasound for Early Diagnosis of Pancreatic Cancer

Detection of small pancreatic cancers, which have a better prognosis than large cancers, is needed to reduce high mortality rates. Endoscopic ultrasound (EUS) is the most sensitive imaging modality for detecting pancreatic lesions. The high resolution of EUS makes it particularly useful for detecting small pancreatic lesions that may be missed by other imaging modalities. Therefore, EUS should be performed in patients with obstructive jaundice in whom computed tomography (CT) or magnetic resonance imaging (MRI) does not identify a definite pancreatic lesion. Interest in the use of EUS for screening individuals at high risk of pancreatic cancer, including those with intraductal papillary mucinous neoplasms (IPMNs) and familial pancreatic cancer is growing. Contrast-enhanced EUS can facilitate differential diagnosis of small solid pancreatic lesions as well as malignant cystic lesions. In addition, EUS-guided fine needle aspiration can provide samples of small pancreatic lesions. Thus, EUS and EUS-related techniques are essential for early diagnosis of pancreatic cancer.

Value of anti-plasminogen binding peptide, anti-carbonic anhydrase II, immunoglobulin G4, and other serological markers for the differentiation of autoimmune pancreatitis and pancreatic cancer

The diagnosis of autoimmune pancreatitis (AIP) and its differential diagnosis from pancreatic cancer (PC) can be challenging. In this retrospective study, we aimed to evaluate the value of anti-plasminogen binding peptide (a-PBP), immunoglobulin G4 (IgG4), and anti-carbonic anhydrase-II (a-CA-II), together with other serological markers whose value is not fully elucidated.The serum levels of a-PBP, IgG4, IgG, anti-nuclear antibodies (ANA), anti-lactoferrin (a-LF), a-CA-II, and rheumatoid factor (RF) were evaluated in patients with AIP (n = 29), PC (n = 17), pancreatic neuroendocrine neoplasm (P-NEN, n = 12), and alcoholic chronic pancreatitis (ACP, n = 41). ANCA were measured in the AIP patients.There was no statistically significant difference in mean a-PBP values in AIP compared with PC. A ROC curve showed that, when using a cut-off of 38.3 U, low values of a-PBP had a sensitivity and specificity of 45% and 71% for differentiating AIP from PC. The sensitivity and specificity of IgG4 (cut-off 1.4 g/L) for differentiating AIP from PC was 45% and 88%, but rose to 52% and 88% when using a cut-off of 1.09 g/L. When using this cut-off, the sensitivity and specificity for differentiating type 1 AIP from PC was 68% and 88%. None of the other markers were significantly changed in AIP versus PC. For differentiation of type 1 and type 2 AIP, the only significant differences were IgG4 in type 1 AIP (P < .01), with a sensitivity of 68% and a specificity of 80%, and c-ANCA elevations found in some type 2 AIP patients (P < .05).The only serological marker for which we found a statistically significant difference in mean values between AIP and PC was IgG4. However, the value of IgG4 for the distinction of AIP from PC was limited, probably in part due to the relatively high number of type 2 AIP patients in our study. In accord with recent publications, our data do not support a role of increased serum a-PBP for the diagnosis of AIP.

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.

Autoimmune pancreatitis: Imaging features

Background and Objectives

Autoimmune pancreatitis (AIP) remains a difficult disease to diagnose before treatment, particularly if presenting as a focal mass lesion. The purpose of this multicenter retrospective study is to analyze imaging features of histologically confirmed AIP to determine the additional diagnostic value of contrast-enhanced ultrasound (CEUS), contrast-enhanced endoscopic ultrasound (CE-EUS), and elastography to B-mode features.

Patients and Methods

We report on a retrospective data collection of 60 histologically confirmed cases of AIP in comparison to 16 patients with pancreatic adenocarcinomas (PDAC). All CE (-E) US examinations were assessed by two independent readers in consensus. The role of CEUS and CE-EUS for pancreatic evaluation was defined according to the 2011 European Federation of Societies for Ultrasound in Medicine and Biology guidelines.

Results

After injection of ultrasound (US) contrast agents, most AIP lesions displayed focal or diffuse isoenhancement (86.6%) in the arterial phase, while most of the PDAC lesions (93.7%) were hypoenhancing (P < 0.01). During the late phase, most AIP lesions were hyper-(65%) or iso-enhancing (35%), while most PDAC lesions were hypoenhancing (93.7%). CE-EUS was performed in a subset of ten patients and showed hyperenhancement in all AIP cases. Most focal AIP lesions (n = 27, 79.4%) were stiffer than the surrounding pancreatic parenchyma.

Conclusions

In this study, percutaneous and endoscopic contrast enhanced harmonic US techniques consistently revealed diffuse and focal types of AIP to have features consistent with vascularized lesions. Differentiation from the typically hypovascularized pancreatic adenocarcinoma was possible with CE (-E) US evaluation.

Serological characteristics of autoimmune pancreatitis and its differential diagnosis from pancreatic cancer by using a combination of carbohydrate antigen 19-9, globulin, eosinophils and hemoglobin

Autoimmune pancreatitis (AIP) is a special type of chronic pancreatitis, which may be misdiagnosed as pancreatic carcinoma. This study aims to verify new biomarkers for AIP and propose a serological pattern to differentiate AIP from pancreatic adenocarcinoma with routinely performed tests. In this study, data of serum samples were collected and compared between 25 patients with AIP and 100 patients with pancreatic carcinoma. Receiver operating characteristic analysis and logistic regression was performed to evaluate the diagnostic effect of serum parameters in differentiating AIP from pancreatic carcinoma alone or in combination. Among several serum markers observed in the two groups, carbohydrate antigen 19-9 (Ca19-9), globulin, eosinophils and hemoglobin were selected as the independent markers. Serum levels of Globulin, Eosinophil percentage in AIP group were significantly higher than in pancreatic cancer group (P<0.05), while hemoglobin and tumor marker CA19-9 levels were lower (P <0.05). The combination of these markers identified patients with AIP with 92% sensitivity and 79% specificity, which indicated relatively high diagnostic value. Elevated serum eosinophils, globulin, together with decreased hemoglobin level can be used as a preoperative indicator for AIP and can help to initiate diagnosis of AIP in time.

[Autoimmune pancreatitis: An update]

CLINICAL/METHODICAL ISSUE

Autoimmune pancreatitis (AIP) is a rare disease, the pathophysiological understanding of which has been greatly improved over the last years. The most common form, type 1 AIP belongs to the IgG4-related diseases and must be distinguished from type 2 AIP, which is a much rarer entity associated with chronic inflammatory bowel disease. Clinically, there is an overlap with pancreatic cancer. Imaging and further criteria, such as serological and histological parameters are utilized for a differentiation between both entities in order to select the appropriate therapy and to avoid the small but ultimately unnecessary number of pancreatectomies.

PERFORMANCE

The diagnostics of AIP are complex, whereby the consensus criteria of the International Association of Pancreatology have become accepted as the parameters for discrimination. These encompass five cardinal criteria and one therapeutic criterion. By applying these criteria AIP can be diagnosed with a sensitivity of 84.9%, a specificity of 100% and an accuracy of 93.8%.

ACHIEVEMENTS

The diagnosis of AIP is accomplished by applying several parameters of which two relate to imaging. As for the routine diagnostics of the pancreas these are ultrasound, computed tomography (CT) and magnetic resonance imaging (MRI). Important for the differential diagnosis is the exclusion of signs of local and remote tumor spread for which CT and MRI are established. The essential diagnostic parameter of histology necessitates sufficient sample material, which cannot usually be acquired by a fine needle biopsy. CT or MRI are the reference standard methods for identification of the optimal puncture site and imaging-assisted (TruCut) biopsy.

PRACTICAL RECOMMENDATIONS

In patients presenting with unspecific upper abdominal pain, painless jaundice combined with the suspicion of a pancreatic malignancy in imaging but a mismatch of secondary signs of malignancy, AIP should also be considered as a differential diagnosis. As the diagnosis of AIP only partially relies on imaging radiologists also have to be aware of the clinical, serological and histological parameters for AIP in order to guide clinicians towards the correct diagnosis. Only in this way can the highly efficient steroid therapy be initiated and otherwise possibly severe forms of therapy be avoided.

Differential diagnosis of small solid pancreatic lesions

BACKGROUND AND AIMS

Pancreatic ductal adenocarcinoma (PDAC) is typically diagnosed at a late stage. Little is known about the incidental finding of early-stage PDAC. The aim of the current study was to determine the etiology of small solid pancreatic lesions (≤15 mm) to optimize clinical management.

METHODS

Inclusion criterion for the retrospective study analysis was the incidental finding of primarily undetermined small solid pancreatic lesions ≤15 mm in 394 asymptomatic patients. Final diagnoses were based on histology or cytology obtained by imaging-guided biopsy (and at least 12-month follow-up) and/or surgery. Contrast-enhanced US or contrast-enhanced EUS was performed in 219 patients.

RESULTS

The final diagnoses of 394 patients were as follows: 146 PDACs, 156 neuroendocrine tumors, 28 metastases into the pancreas from other primary sites, and 64 various other etiologies. Contrast-enhanced US allowed differential diagnosis of PDAC and non-PDAC in 189 of 219 patients (86%).

CONCLUSIONS

Approximately 40% of patients with small solid pancreatic lesions had very early stage PDAC. Approximately 60% of small solid pancreatic lesions ≤15 mm are not PDAC and, therefore, do not require radical surgery. Without preoperative diagnosis, an unacceptably large proportion of patients would be exposed to radical surgery with significant morbidity and mortality.

Differential Diagnosis of Autoimmune Pancreatitis From Pancreatic Cancer by Analysis of Serum Gelatinase Levels

OBJECTIVES

The aim of this study was to analyze serum gelatinases as part of the clinical strategy for the preoperative differentiation between autoimmune pancreatitis (AIP) and pancreatic ductal adenocarcinoma (PDAC). The finding of differential markers will prevent unnecessary surgical resection and allow optimal treatment of these diseases.

METHODS

Quantitative gelatin zymography was applied to analyze all individual gelatinase forms in serum and to define proteinase alterations associated with AIP and PDAC. For this purpose, sera of 130 patients, being 29 with AIP, 33 with chronic pancreatitis, 32 with PDAC, and 36 healthy controls, were first assayed for gelatinase levels by quantitative zymography before further validation by the analysis with commercial sandwich enzyme linked immunosorbent assays.

RESULTS

Serum profiling data obtained by zymography analysis revealed that gelatinase B/matrix metalloproteinase 9 (MMP-9), the neutrophil gelatinase B-associated lipocalin/MMP-9 complex, and gelatinase A/MMP-2 levels were significantly increased in patients with AIP. These proteins are promising markers to discriminate between AIP and PDAC. The best composite parameter, being the ratio of total MMP-9 over MMP-2 levels, can predict 93% of the AIP and 75% of the PDAC correctly. With enzyme linked immunosorbent assay, we confirmed the zymography results.

CONCLUSIONS

Differential gelatinase serum profiles as AIP markers, together with other clinical tests, help to assure the diagnosis of PDAC or AIP.

Serum IgG4 and IgG for the diagnosis of autoimmune pancreatitis: A systematic review with meta-analysis

BACKGROUND AND OBJECTIVE

The correct diagnosis of autoimmune pancreatitis (AIP) is a clinical challenge. Emerging published data on the accuracy of serum IgG4 and IgG for diagnosing AIP are inconsistent. This study was performed to better elucidate the accuracy of serum IgG4 and IgG in diagnosing AIP.

METHODS

A comprehensive literature search of PubMed, Web of Science, EMBASE, the Cochrane Library and some other databases was conducted before October 2014. The methodological quality of each study was assessed according to the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) checklist. Random-effects model was used to summarize the sensitivity, specificity and other measures of accuracy.

RESULTS

Fifteen studies on IgG4 and 8 studies on IgG were included. The summary estimates for serum IgG4 in distinguishing AIP from the overall controls, pancreatic cancer and ordinary chronic pancreatitis were as follows: sensitivity 0.74 (0.70-0.77), 0.73 (0.69-0.77) and 0.76 (0.72-0.80), respectively, specificity, 0.94 (0.93-0.95), 0.93 (0.91-0.95) and 0.96 (0.95-0.97), respectively. The summary estimates for serum IgG in distinguishing AIP from the overall controls and pancreatic cancer were as follows: sensitivity, 0.53 (0.47-0.59) and 0.51 (0.44-0.57), respectively, specificity, 0.87 (0.85-0.89) and 0.94 (0.91-0.96), respectively. The area under the curve (AUC) of serum IgG in distinguishing AIP from ordinary chronic pancreatitis was 0.657.

CONCLUSIONS

Both serum IgG4 and IgG have high specificity and relatively low sensitivity for diagnosing AIP. Besides, they are useful for distinguishing AIP from pancreatic cancer and ordinary chronic pancreatitis. To better elucidate the usefulness of serum IgG4 and IgG, further studies are needed.

[Surgery for pancreatic cancer: Evidence-based surgical strategies]

Pancreatic cancer surgery represents a challenge for surgeons due to its technical complexity, the potential complications that may appear, and ultimately because of its poor survival. The aim of this article is to summarize the scientific evidence regarding the surgical treatment of pancreatic cancer in order to help surgeons in the decision making process in the management of these patients .Here we will review such fundamental issues as the need for a biopsy before surgery, the type of pancreatic anastomosis leading to better results, and the need for placement of drains after pancreatic surgery will be discussed.

IgG4-related autoimmune diseases: Polymorphous presentation complicates diagnosis and treatment

BACKGROUND

IgG4-associated autoimmune diseases are systemic diseases affecting multiple organs of the body. Autoimmune pancreatitis, with a prevalence of 2.2 per 100,000 people, is one such disease. Because these multi-organ diseases present in highly variable ways, they were long thought just to affect individual organ systems. This only underscores the importance of familiarity with these diseases for routine clinical practice.

METHODS

This review is based on pertinent articles retrieved by a selective search in PubMed, and on the published conclusions of international consensus conferences.

RESULTS

The current scientific understanding of this group of diseases is based largely on case reports and small case series; there have not been any randomized controlled trials (RCTs) to date. Any organ system can be affected, including (for example) the biliary pathways, salivary glands, kidneys, lymph nodes, thyroid gland, and blood vessels. Macroscopically, these diseases cause diffuse organ swelling and the formation of pseudotumorous masses. Histopathologically, they are characterized by a lymphoplasmacytic infiltrate with IgG4-positive plasma cells, which leads via an autoimmune mechanism to the typical histologic findings--storiform fibrosis ("storiform" = whorled, like a straw mat) and obliterative, i.e., vessel-occluding, phlebitis. A mixed Th1 and Th2 immune response seems to play an important role in pathogenesis, while the role of IgG4 antibodies, which are not pathogenic in themselves, is still unclear. Glucocorticoid treatment leads to remission in 98% of cases and is usually continued for 12 months as maintenance therapy. Most patients undergo remission even if untreated. Steroid-resistant disease can be treated with immune modulators.

CONCLUSION

IgG4-associated autoimmune diseases are becoming more common, but adequate, systematically obtained data are now available only from certain Asian countries. Interdisciplinary collaboration is a prerequisite to proper diagnosis and treatment. Treatment algorithms and RCTs are needed to point the way to organ-specific treatment in the future.

Evaluation of pCLE in the bile duct: final results of EMID study : pCLE: impact in the management of bile duct strictures

INTRODUCTION

Pre-operative histology of bile duct stenosis is associated with low accuracy. Probe confocal laser endomicroscopy (pCLE) enables optical biopsy or in vivo histology. The definitive results of the EMID study are presented here, comparing optical biopsies with definitive histology.

AIMS AND METHODS

Sixty one patients with a biliary stricture without any previous histology were included (July 2007-May 2012). An endoscopic ultrasound (EUS) had to be conducted before the ERCP procedure. pCLE was done using CholangioFlex during the ERCP procedure. Results were compared to those of definitive histology obtained by biopsy or surgery in case of malignant lesions, and by surgery or 1-year follow-up in case of benign lesions.

RESULTS

Six patients were excluded because no definitive histology was available. There were 41 malignant lesions and 14 benign lesions. Sensitivity, specificity, PPV, NPV, and accuracy with combination of pCLE with endobiliary and EUS biopsies were 100, 71, 91, 100, and 93%, respectively (with a significant increase of accuracy compared with endobiliary and EUS biopsies without pCLE, p = 0.03). 19 patients had a biliary stricture without individualized mass (6 malignant lesions, 13 benign lesions). Sensitivity, specificity, PPV, NPV, and accuracy for pCLE were 83, 77, 62, 91, and 79%, respectively. Sensitivity, specificity, PPV, NPV, and accuracy for combination of pCLE with endobiliary and EUS biopsies were 100, 69, 60, 100, and 79%, respectively.

CONCLUSION

The addition of a pCLE procedure in the diagnostic histologic examination of a biliary stricture permits a significant increase in diagnostic reliability and allows for a VPN of 100%.

Frequency and characterization of benign lesions in patients undergoing surgery for the suspicion of solid pancreatic neoplasm

OBJECTIVES

A diagnosis of benign lesions (BLs) is reported in 5% to 21% of pancreatoduodenectomies performed for neoplasms; no data for body-tail resections are available. The aims were to investigate the frequency and characterize the BLs mimicking cancer in the head and the body-tail of the pancreas.

METHODS

This study is a retrospective review of pancreatic specimenscollected from 2005 to 2011 in the pathology database of Mainz (Germany). Patients with final diagnosis excluding malignancy were analyzed by histology, imaging, and clinical aspects.

RESULTS

Among 373 patients, 33 patients (8.8%) were diagnosed with a benign disease: 25 (8.4%) of 298 in the pancreatic head and 8 (10.7%) of 75 in the body-tail resections. Paraduodenal pancreatitis was diagnosed in 13 (3.5%) of 373 patients; autoimmune pancreatitis (AIP), in 11 (2.9%); "ordinary" chronic pancreatitis, in 6 (1.6%); and accessory spleen, in 3 (0.8%). In pancreatic head resections, the most frequent diagnoses were paraduodenal pancreatitis (13/298, 4.4%) and AIP (9/298, 3%), whereas in the body-tail, the most frequent diagnoses were accessory spleen (3/75, 4%), chronic pancreatitis (3/75, 4%), and AIP (2/75, 2.7%).

CONCLUSIONS

Benign lesions are observed with the same frequency inspecimens of the head or the body-tail of the pancreas.

Utility of serum IgG, IgG4 and carbonic anhydrase II antibodies in distinguishing autoimmune pancreatitis from pancreatic cancer and chronic pancreatitis

PURPOSE

Autoimmune pancreatitis (AIP) can mimic pancreatic cancer in its clinical presentation, imaging features and laboratory parameters. The aim of our study was to compare IgG, IgG4 and anti-CAIIAb serum levels in patients with AIP, pancreatic adenocarcinoma (PA) and chronic pancreatitis (CP) and to assess their clinical significance and utility in differential diagnosis of pancreatic diseases.

PATIENT/METHODS

The study included 124 patients: 45 with PA, 24 with AIP and 55 with CP. Peripheral venous blood samples were obtained from all analyzed patients at the time of hospital admission and total IgG, IgG4 and anti-CAIIAB serum levels were measured using ELISA tests.

RESULTS

Serum levels of IgG, IgG4 and anti-CAIIAb were significantly higher in patients with AIP compared to PA and CP patients (p<0.001). In AIP patients the median IgG levels were 19.7 g/l, IgG4 levels - 301.9 mg/dl and anti-CAIIAb - 81.82 ng/ml, compared to 10.61 g/l, 123.2mg/dl and 28.6 ng/ml, respectively, in PA patients. IgG4 for the cut-off 210 mg/dl showed the best sensitivity and specificity (83.8% and 89.5%) in AIP diagnosis compared to IgG (69.3% and 87.3%, respectively) and anti-CAIIAb (45.3% and 74.3%). However, 16 (35.5%) patients with PA and 14 (25.4%) patients with CP had IgG4 levels greater than 140 mg/dl. Moreover, in 3 (6.67%) patients with pancreatic cancer those values were greater than 280 mg/dl. No patients with CP had IgG4 more than 280 mg/dl.

CONCLUSIONS

IgG4 at cut-off 210 mg/dl showed the best sensitivity and specificity in AIP diagnosis compared to IgG and anti-CAIIAb, however elevations of serum IgG4 may be seen in subjects without AIP, including pancreatic cancer.

Increased Incidence of Benign Pancreatic Pathology following Pancreaticoduodenectomy for Presumed Malignancy over 10 Years despite Increased Use of Endoscopic Ultrasound

Despite using imaging studies, tissue sampling, and serologic tests about 5-10% of surgeries done for presumed pancreatic malignancies will have benign findings on final pathology. Endoscopic ultrasound (EUS) is used with increasing frequency to study pancreatic masses. The aim of this study is to examine the effect of EUS on prevalence of benign diseases undergoing Whipple over the last decade. Patients who underwent Whipple procedure for presumed malignancy at Emory University Hospital from 1998 to 2011 were selected. Demographic data, history of smoking and drinking, history of diabetes and pancreatitis, imaging data, pathology reports, and tumor markers were extracted. 878 patients were found. 95 (10.82%) patients had benign disease. Prevalence of benign finding had increased over the recent years despite using more EUS. Logistic regression models showed that abdominal pain (OR: 5.829, 95% CI 2.681-12.674, P ≤ 0.001) and alcohol abuse (OR: 3.221, CI 95%: 1.362-7.261, P: 0.002) were predictors of benign diseases. Jaundice (OR: 0.221, 95% CI: 0.084-0.58, P: 0.002), mass (OR: 0.145, 95% CI: 0.043-0.485, P: 0.008), and ductal dilation (OR: 0.297, 95% CI 0.134-0.657, P: 0.003) were associated with malignancy. Use of imaging studies, ERCP, and EUS has not decreased the percentage of benign findings after surgery for presumed pancreatic malignancy.

Serum level of Ca 19-9 increases ability of IgG4 test to distinguish patients with autoimmune pancreatitis from those with pancreatic carcinoma

BACKGROUND

Autoimmune pancreatitis (AIP) is often difficult to distinguish from pancreatic carcinoma or other pancreatobiliary diseases. High serum levels of carbohydrate antigen 19-9 (Ca 19-9) are indicative of malignancies, whereas high levels of immunoglobulin (Ig)G4 (>1.4 g/l) are characteristic of AIP. We investigated whether serum levels of these proteins can differentiate between these diseases.

METHODS

We measured levels of Ca 19-9 and IgG4 in serum samples from 33 patients with AIP, 53 with pancreatic carcinoma, and 145 with other pancreatobiliary disorders. We determined cut-off levels for each assay. Logistic regression analysis was used to evaluate combined data on Ca 19-9, IgG4, and bilirubin levels.

RESULTS

Low levels of Ca 19-9 were independently associated with AIP, compared with pancreatic adenocarcinoma [odds ratio (OR) 0.28; 95% confidence interval (CI) 0.13-0.59; p = 0.0001]. Using an upper level of 74 U/ml, the assay for Ca 19-9 identified patients with AIP with 73% sensitivity and 74% specificity. Using a lower level of 2.6 g/l, the assay for IgG4 identified these patients with 70% sensitivity and 100% specificity. Combining data, levels of Ca 19-9 < 74 U/ml and IgG4 > 1.0 g/l identified patients with AIP with 94% sensitivity and 100 % specificity.

CONCLUSIONS

Patients with AIP have lower levels of Ca 19-9 than those patients with pancreatic carcinoma. Measurement of either the Ca 19-9 or the IgG4 level alone are not accurate enough for diagnosis. However, the combination of Ca 19-9 < 74 U/ml and IgG4 > 1.0 g/l distinguishes patients with AIP from those patients with pancreatic carcinoma with 94% sensitivity and 100% specificity.

Preoperative characteristics of patients with presumed pancreatic cancer but ultimately benign disease: a multicenter series of 344 pancreatoduodenectomies

BACKGROUND

Preoperative differentiation between malignant and benign pancreatic tumors can be difficult. Consequently, a proportion of patients undergoing pancreatoduodenectomy for suspected malignancy will ultimately have benign disease. The aim of this study was to compare preoperative clinical and diagnostic characteristics of patients with unexpected benign disease after pancreatoduodenectomy with those of patients with confirmed (pre)malignant disease.

METHODS

We performed a multicenter retrospective cohort study in 1,629 consecutive patients undergoing pancreatoduodenectomy for suspected malignancy between 2003 and 2010 in 11 Dutch centers. Preoperative characteristics were compared in a benign:malignant ratio of 1:3. Malignant cases were selected from the entire cohort by using a random number list. A multivariable logistic regression prediction model was constructed to predict benign disease.

RESULTS

Of 107 patients (6.6 %) with unexpected benign disease after pancreatoduodenectomy, 86 fulfilled the inclusion criteria and were compared with 258 patients with (pre)malignant disease. Patients with benign disease presented more often with pain (56 vs. 38 %; P = 0.004), but less frequently with jaundice (60 vs. 80 %; P < 0.01), a pancreatic mass (13 vs. 54 %, P < 0.001), or a double duct sign on computed tomography (21 vs. 47 %; P < 0.001). In a prediction model using these parameters, only 19 % of patients with benign disease were correctly predicted, and 1.4 % of patients with malignant disease were missed.

CONCLUSIONS

Nearly 7 % of patients undergoing pancreatoduodenectomy for suspected malignancy were ultimately diagnosed with benign disease. Although some preoperative clinical and imaging characteristics might indicate absence of malignancy, their discriminatory value is insufficient for clinical use.