Autoimmune pancreatitis and pancreatic cancer: Epidemiological aspects and immunological considerations

Maintenance steroid therapy is associated with decreased risk of malignancy and better prognosis of patients with autoimmune pancreatitis: A multicenter cohort study in Japan

BACKGROUND/OBJECTIVES

The association between autoimmune pancreatitis (AIP) and pancreatic cancer (PC) remains controversial. This study aimed to clarify the long-term prognosis and risk of malignancies in AIP patients in Japan.

METHODS

We conducted a multicenter retrospective cohort study on 1364 patients with type 1 AIP from 20 institutions in Japan. We calculated the standardized incidence ratio (SIR) for malignancies compared to that in the general population. We analyzed factors associated with overall survival, pancreatic exocrine insufficiency, diabetes mellitus, and osteoporosis.

RESULTS

The SIR for all malignancies was increased (1.21 [95 % confidence interval: 1.05-1.41]) in patients with AIP. Among all malignancies, the SIR was highest for PC (3.22 [1.99-5.13]) and increased within 2 years and after 5 years of AIP diagnosis. Steroid use for ≥6 months and ≥50 months increased the risk of subsequent development of diabetes mellitus and osteoporosis, respectively. Age ≥65 years at AIP diagnosis (hazard ratio [HR] = 3.73) and the development of malignancies (HR = 2.63), including PC (HR = 7.81), were associated with a poor prognosis, whereas maintenance steroid therapy was associated with a better prognosis (HR = 0.35) in the multivariate analysis. Maintenance steroid therapy was associated with a better prognosis even after propensity score matching for age and sex.

CONCLUSIONS

Patients with AIP are at increased risk of developing malignancy, especially PC. PC is a critical prognostic factor for patients with AIP. Although maintenance steroid therapy negatively impacts diabetes mellitus and osteoporosis, it is associated with decreased cancer risk and improved overall survival.

Challenges and pitfalls in the diagnosis of IgG4-related disease

IgG4-related disease (IgG4-RD) is a relatively novel fibroinflammatory condition characterized typically by dense lymphoplasmacytic inflammation, storiform fibrosis and obliterative venulitis, together with prominent IgG4+ plasma cells and an IgG4+/IgG+ plasma cell ratio of >40 %. The diagnosis is usually made on a combination of clinical and serological features together with characteristic radiological and histological appearances. The condition may be limited to a single tissue/organ (e.g., autoimmune pancreatitis) or may be multicentric in nature - four clinical 'patterns' of disease distribution have recently been described. The diagnosis of IgG4-RD can be challenging, particularly when the clinical presentation is unusual and/or when the histological features are not typical. A diagnosis of IgG4-RD may still be achieved in these situations, after careful clinicopathological discussion e.g., at a specialist multidisciplinary team meeting. However, a wide range of other conditions (neoplastic and non-neoplastic) can mimic IgG4-RD, clinically and/or on histological examination. The relationship between IgG4-RD and non-IgG4-RD associated conditions in some clinical situations is particularly complex. This review describes the role of histological examination in the diagnosis of IgG4-RD, discusses some of the practical difficulties that may be encountered and provides an insight into the range of non-IgG4-RD associated conditions that can mimic IgG4-RD on clinical and/or histological grounds. The requirement for interpretation of histological features in the context of the global clinical picture of the patient is highlighted and emphasized.

Treatment approaches in autoimmune pancreatitis (Review)

Autoimmune pancreatitis (AIP) is a rare disease. There are two distinct types of AIP: AIP type 1 (AIP-1), a pancreatic manifestation of a multi-organ disease linked to immunoglobulin (Ig)G4, and AIP type 2 (AIP-2), a pancreas-specific disease unrelated to IgG4. The usual course of treatment for AIP is oral corticosteroid medication. Rituximab has also been recommended for recurrent AIP-1 in order to initiate remission and provide ongoing treatment. Immunomodulators such as azathioprine are used to keep certain patients in remission. Evaluation also takes into account a number of pharmacological alternatives, including biologic drugs like anti-tumor necrosis factor therapy, a safe and efficient second-line treatment for AIP-2 relapse or steroid dependence. Corticosteroids and immunosuppressants, which are poorly tolerated due to considerable side effects, are being replaced by other biologic drugs, which may offer a beneficial therapeutic alternative.

Diagnostic Differentiation between Pancreatitis and Pancreatic Cancer: A Scoping Review

Pancreatitis, encompassing acute and chronic forms, and pancreatic cancer pose significant challenges to the exocrine tissue of the pancreas. Recurrence rates and complications following acute pancreatitis episodes can lead to long-term risks, including diabetes mellitus. Chronic pancreatitis can develop in approximately 15% of cases, regardless of the initial episode's severity. Alcohol-induced pancreatitis, idiopathic causes, cigarette smoking, and hereditary pancreatitis contribute to the progression to chronic pancreatitis. Chronic pancreatitis is associated with an increased risk of pancreatic cancer, with older age at onset and smoking identified as risk factors. This scoping review aims to synthesise recent publications (2017-2022) on the diagnostic differentiation between pancreatitis and pancreatic cancer while identifying knowledge gaps in the field. The review focuses on biomarkers and imaging techniques in individuals with pancreatitis and pancreatic cancer. Promising biomarkers such as faecal elastase-1 and specific chemokines offer non-invasive ways to assess pancreatic insufficiency and detect early biomarkers for chronic pancreatitis. Imaging techniques, including computed tomography (CT), magnetic resonance imaging (MRI), endoscopic ultrasound (EUS), and positron emission tomography (PET), aid in differentiating between chronic pancreatitis and pancreatic cancer. However, accurately distinguishing between the two conditions remains a challenge, particularly when a mass is present in the head of the pancreas. Several knowledge gaps persist despite advancements in understanding the association between pancreatitis and pancreatic cancer, including the correlation between histopathological grading systems, non-invasive imaging techniques, and biomarkers in chronic pancreatitis to determine the risk of progression to pancreatic cancer, as well as differentiating between the two conditions. Further research is necessary to enhance our understanding of these aspects, which can ultimately improve the diagnosis and management of pancreatitis and pancreatic cancer.

Pancreatic cancer detected with 18F-FDG PET/CT in a case of IgG4-related disease

We present a case of a 67-year-old male presenting with severe abdominal pain, laboratory tests revealed IgG levels of 63.5 g/L, IgG4 levels of 63.7 g/L, and negative results for ANCA (Anti-Neutrophil Cytoplasmic Antibodies), Hematuria immunofixation electrophoresis, as well as Cold globulin qualitative test. 18F-FDG PET/CT revealed multiple lesions with increased metabolism in the submaxillary saliva gland, intrahepatic bile ducts, prostate, seminal vesicle glands, and the body of the pancreas. Additionally, a circular cystic-solid lesion with metabolic heterogeneity was observed in the head of the pancreas, accompanied by visible dilatation of the pancreatic duct. The diagnostic imaging suggested IgG4-related disease (IgG4-RD), while pancreatic malignancy could not be definitively ruled out. The patient underwent fine-needle aspiration (FNA) biopsies of lung nodules and the prostate gland, all of which were consistent with the diagnosis of IgG4-RD. Additionally, FNA biopsy of a pancreatic lesion is consistent with the diagnosis of pancreatic ductal adenocarcinoma.

Autoimmune pancreatitis type 2 (idiopathic duct-centric pancreatitis): A comprehensive review

Autoimmune pancreatitis (AIP) is an uncommon fibro-inflammatory disorder precipitated by autoimmune/inflammatory reactions. Currently, there are two clinical subtypes of AIP (type 1 [AIP-1] and type 2 [AIP-2]) that correspond to two histologic descriptors (lymphoplasmacytic sclerosing pancreatitis and idiopathic duct-centric pancreatitis, respectively). While our understanding of AIP-1 has evolved considerably over the years, little is known about AIP-2 due to its rarity, often leading to misdiagnosis, delayed treatment, and even unnecessary surgical resection. Compared to AIP-1, AIP-2 exhibits distinct clinical and histologic features. Because AIP-2 is a pancreas-restricted disease without a specific serum marker, the evaluation of histologic features (e.g., granulocytic epithelial lesions) is essential for an accurate diagnosis. Patients with AIP-2 respond well to glucocorticoids, with anti-tumor necrosis factor-alpha antibodies as a promising alternative therapy. The prognosis of AIP-2 is generally favorable and relapse is uncommon. Here, we provide an overview of our current knowledge on the clinical features, diagnosis, therapeutic regimens, prognosis, and putative mechanisms underlying AIP-2. Notably, the diagnostic differentiation between AIP-2, especially the mass-forming/focal type, and pancreatic cancer is important, but challenging. In this regard, endoscopic ultrasound-guided core biopsy has a key role, but novel diagnostic markers and modalities are clearly needed.

Incidence, prevalence, and comorbidities of chronic pancreatitis: A 7-year population-based study

BACKGROUND

Chronic pancreatitis (CP) is a fibroinflammatory syndrome leading to reduced quality of life and shortened life expectancy. Population-based estimates of the incidence, prevalence, and comorbidities of CP in China are scarce.

AIM

To characterize the incidence, prevalence, and comorbidities of CP in Sichuan Province, China, with population-based data.

METHODS

Data on CP from 2015 to 2021 were obtained from the Health Information Center of Sichuan Province. During the study period, a total of 38090 individuals were diagnosed with CP in Sichuan Province. The yearly incidence rate and point prevalence rate (December 31, 2021) of CP were calculated. The prevalence of comorbid conditions in CP patients was estimated. The annual number of CP-related hospitalizations, hospital length of stay, and hospitalization costs for CP were evaluated. Yearly incidence rates were standardized for age by the direct method using the permanent population of Sichuan Province in the 2020 census as the standard population. An analysis of variance test for the linearity of scaled variables and the Cochran-Armitage trend test for categorical data were performed to investigate the yearly trends, and a two-sided test with P < 0.05 was considered statistically significant.

RESULTS

The 38090 CP patients comprised 23280 males and 14810 females. The mean age of patients at CP diagnosis was 57.83 years, with male patients (55.87 years) being younger than female patients (60.11 years) (P < 0.001). The mean incidence rate of CP during the study period was 6.81 per 100000 person-years, and the incidence of CP increased each year, from 4.03 per 100000 person-years in 2015 to 8.27 per 100000 person-years in 2021 (P < 0.001). The point prevalence rate of CP in 2021 was 45.52 per 100000 individuals for the total population, with rates of 55.04 per 100000 individuals for men and 35.78 per 100000 individuals for women (P < 0.001). Individuals aged 65 years or older had the highest prevalence of CP (113.38 per 100000 individuals) (P < 0.001). Diabetes (26.32%) was the most common comorbidity in CP patients. The number of CP-related hospitalizations increased from 3739 in 2015 to 11009 in 2021. The total costs for CP-related hospitalizations for CP patients over the study period were 667.96 million yuan, with an average of 17538 yuan per patient.

CONCLUSION

The yearly incidence of CP is increasing, and the overall CP hospitalization cost has increased by 1.4 times during the last 7 years, indicating that CP remains a heavy health burden.

Pancreatic cancer, autoimmune or chronic pancreatitis, beyond tissue diagnosis: Collateral imaging and clinical characteristics may differentiate them

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies and is developing into the 2^nd leading cause of cancer-related death. Often, the clinical and radiological presentation of PDAC may be mirrored by other inflammatory pancreatic masses, such as autoimmune pancreatitis (AIP) and mass-forming chronic pancreatitis (MFCP), making its diagnosis challenging. Differentiating AIP and MFCP from PDAC is vital due to significant therapeutic and prognostic implications. Current diagnostic criteria and tools allow the precise differentiation of benign from malignant masses; however, the diagnostic accuracy is imperfect. Major pancreatic resections have been performed in AIP cases under initial suspicion of PDAC after a diagnostic approach failed to provide an accurate diagnosis. It is not unusual that after a thorough diagnostic evaluation, the clinician is confronted with a pancreatic mass with uncertain diagnosis. In those cases, a re-evaluation must be entertained, preferably by an experienced multispecialty team including radiologists, pathologists, gastroenterologists, and surgeons, looking for disease-specific clinical, imaging, and histological hallmarks or collateral evidence that could favor a specific diagnosis. Our aim is to describe current diagnostic limitations that hinder our ability to reach an accurate diagnosis among AIP, PDAC, and MFCP and to highlight those disease-specific clinical, radiological, serological, and histological characteristics that could support the presence of any of these three disorders when facing a pancreatic mass with uncertain diagnosis after an initial diagnostic approach has been unsuccessful.

Pancreatic Cancer in Chronic Pancreatitis: Pathogenesis and Diagnostic Approach

Chronic pancreatitis is one of the main risk factors for pancreatic cancer, but it is a rare event. Inflammation and oncogenes work hand in hand as key promoters of this disease. Tobacco is another co-factor. During alcoholic chronic pancreatitis, the cumulative risk of cancer is estimated at 4% after 15 to 20 years. This cumulative risk is higher in hereditary pancreatitis: 19 and 12% in the case of PRSS1 and SPINK1 mutations, respectively, at an age of 60 years. The diagnosis is difficult due to: (i) clinical symptoms of cancer shared with those of chronic pancreatitis; (ii) the parenchymal and ductal remodeling of chronic pancreatitis rendering imaging analysis difficult; and (iii) differential diagnoses, such as pseudo-tumorous chronic pancreatitis and paraduodenal pancreatitis. Nevertheless, the occurrence of cancer during chronic pancreatitis must be suspected in the case of back pain, weight loss, unbalanced diabetes, and jaundice, despite alcohol withdrawal. Imaging must be systematically reviewed. Endoscopic ultrasound-guided fine-needle biopsy can contribute by targeting suspicious tissue areas with the help of molecular biology (search for KRAS, TP53, CDKN2A, DPC4 mutations). Short-term follow-up of patients is necessary at the clinical and paraclinical levels to try to diagnose cancer at a surgically curable stage. Pancreatic surgery is sometimes necessary if there is any doubt.

Pancreatitis and Pancreatic Cancer Risk

Purpose: The present retrospective study aimed to explore the relationship between pancreatitis and pancreatic cancer in the population cohort of the UK Biobank (UKB) (https://www.ukbiobank.ac.uk). Methods: From the 500 thousand population cohort of UKB, according to the age and gender of patients with pancreatic cancer 1:10, matching the control without pancreatic cancer, the binary Logistic regression model was used to analyze the relationship between pancreatitis and pancreatic cancer, and subgroup analyses were used to identify potential effect modifiers. Results: A total of 1538 patients with pancreatic cancer were compared with 15 380 controls. In the fully adjusted model, patients with pancreatitis had a significantly increased risk of pancreatic cancer compared with no pancreatitis. The risk of pancreatitis and pancreatic cancer increased with the age of pancreatitis, and the risk of pancreatic cancer was highest in the 61 to 70 age group. In addition, in the first 3 years of acute pancreatitis, the risk of pancreatic cancer increased significantly with the increase in the duration of the disease (odds ratio [OR] 29.13, 95% confidence interval [CI]: 16.34-51.93), after 3 years, the trend of increase decreased. After more than 10 years, there was no significant correlation between the risk of acute pancreatitis and pancreatic cancer. However, patients with chronic pancreatitis were significantly associated with an increased risk of pancreatic cancer only in the first 3 years (OR 28.14, 95% CI: 14.86-53.31). Conclusion: Pancreatitis may associate with an increased risk of pancreatic cancer. The older the age of pancreatitis, the higher the risk of pancreatic cancer. The risk of pancreatic cancer increases significantly in the first 3 years of the course of pancreatitis. This may provide an alternative strategy for the early identification of individuals at high risk of pancreatic cancer.

Diagnosis, severity stratification and management of adult acute pancreatitis–current evidence and controversies

Acute pancreatitis (AP) is a disease spectrum ranging from mild to severe with an unpredictable natural course. Majority of cases (80%) are mild and self-limiting. However, severe AP (SAP) has a mortality risk of up to 30%. Establishing aetiology and risk stratification are essential pillars of clinical care. Idiopathic AP is a diagnosis of exclusion which should only be used after extended investigations fail to identify a cause. Tenets of management of mild AP include pain control and management of aetiology to prevent recurrence. In SAP, patients should be resuscitated with goal-directed fluid therapy using crystalloids and admitted to critical care unit. Routine prophylactic antibiotics have limited clinical benefit and should not be given in SAP. Patients able to tolerate oral intake should be given early enteral nutrition rather than nil by mouth or parenteral nutrition. If unable to tolerate per-orally, nasogastric feeding may be attempted and routine post-pyloric feeding has limited evidence of clinical benefit. Endoscopic retrograde cholangiopancreatogram should be selectively performed in patients with biliary obstruction or suspicion of acute cholangitis. Delayed step-up strategy including percutaneous retroperitoneal drainage, endoscopic debridement, or minimal-access necrosectomy are sufficient in most SAP patients. Patients should be monitored for diabetes mellitus and pseudocyst.

Autoimmune Pancreatitis: From Pathogenesis to Treatment

Autoimmune pancreatitis (AIP) is a rare disease. The diagnosis of AIP is difficult and should be made by a comprehensive evaluation of clinical, radiological, serological, and pathological findings. Two different types of AIP have been identified: autoimmune pancreatitis type 1 (AIP-1), which is considered a pancreatic manifestation of multiorgan disease related to IgG4, and autoimmune pancreatitis type 2 (AIP-2), which is considered a pancreas-specific disease not related to IgG4. Although the pathophysiological conditions seem to differ between type 1 and type 2 pancreatitis, both respond well to steroid medications. In this review, we focused on the pathogenesis of the disease to develop a tool that could facilitate diagnosis and lead to the discovery of new therapeutic strategies to combat autoimmune pancreatitis and its relapses. The standard therapy for AIP is oral administration of corticosteroids. Rituximab (RTX) has also been proposed for induction of remission and maintenance therapy in relapsing AIP-1. In selected patients, immunomodulators such as azathioprine are used to maintain remission. The strength of this review, compared with previous studies, is that it focuses on the clear difference between the two types of autoimmune pancreatitis with a clearly delineated and separate pathogenesis. In addition, the review also considers various therapeutic options, including biologic drugs, such as anti-tumor necrosis factor (TNF) therapy, a well-tolerated and effective second-line therapy for AIP type 2 relapses or steroid dependence. Other biologic therapies are also being explored that could provide a useful therapeutic alternative to corticosteroids and immunosuppressants, which are poorly tolerated due to significant side effects.

"Stomach mass" as the first manifestation of IgG4-related disease: a case report

BACKGROUND

IgG4-related disease mainly manifests as organomegaly and is accompanied by tissue fibrosis (Mimori, Mod Rheumatol 29(2):213, 2019) which is frequently confused with tumour (Dawei et al., J Gastroenterol Hepatol 29(12):1375-8, 2020). There are few reports with of IgG4-related disease with the first clinical manifestation involving the stomach.

CASE PRESENTATION

We present the case of 46-year-old male patient with a "stomach tumour" as the first manifestation of IgG4-related disease. Gastroscopy showed a mass in the stomach, however, the pathology result was chronic inflammation with IgG4 positivity. CT scans of abdomen showed that the stomach wall was thick, the head of the pancreas was swollen, and retroperitoneal fibrosis was severe.The serum IgG4 level was 75 g/L (normal range 0.03-2.01 g/L).After treatment with methylprednisolone for one month, the symptoms were greatly relieved.

CONCLUSIONS

To reduce the suffering of patients and relieve their financial burden, we should consider the possibility of IgG4-related disease when the initial manifestation is a stomach mass.