Current status of type 1 (IgG4-related) autoimmune pancreatitis

Recent advances in IgG4-related autoimmune pancreatitis

The incidence of IgG4-related autoimmune pancreatitis (IgG4-AIP) is high in Asia and other countries, and unnecessary treatment is often undertaken due to both missed diagnosis and misdiagnosis in clinical practice. Although IgG4-AIP has attracted increasing attention, the details of IgG4-AIP pathogenesis and systemic immune response, including its relationship to tumor pathogenesis, are still unclear. In recent years, research on serum immunological detection, pathological features, clinical manifestations, diagnosis and treatment measures for IgG4-AIP has gradually increased. It is of great importance to summarize and discuss the latest progress regarding IgG4-AIP disease.

Understanding autoimmune pancreatitis: Clinical features, management challenges, and association with malignancies

In this editorial we comment on the article by Jaber et al. Autoimmune pancreatitis (AIP) represents a distinct form of pancreatitis, categorized into AIP-1 and AIP-2, characterized by obstructive jaundice, lymphoplasmacytic infiltrate, and fibrosis. AIP-1, associated with elevated immunoglobulin G4 (IgG4) levels, exhibits higher relapse rates, affecting older males, while AIP-2 is less common and linked to inflammatory bowel disease. AIP is considered a manifestation of IgG4-related systemic disease, sharing characteristic histological findings. Steroids are the primary treatment, with emerging biomarkers like interferon alpha and interleukin-33. AIP poses an increased risk of various malignancies, and the association with pancreatic cancer is debated. Surgery is reserved for severe cases, necessitating careful evaluation due to diagnostic challenges. AIP patients may have concurrent PanINs but display favorable long-term outcomes compared to pancreatic cancer patients. Thorough diagnostic assessment, including biopsy and steroid response, is crucial for informed surgical decisions in AIP.

IgG4-related pancreatobiliary diseases could be associated with onset of pancreatobiliary cancer: A multicenter cohort study

BACKGROUND

The risk and prognosis of pancreatobiliary cancer and in patients with autoimmune pancreatitis (AIP) and IgG4-related sclerosing cholangitis (IgG4-SC) remain unclear. Therefore, we retrospectively investigated the risk of pancreatobiliary cancer and prognosis in patients with AIP and IgG4-SC.

METHODS

Patients with AIP and IgG4-SC at seven centers between 1998 and 2022 were investigated. The following data were evaluated: (1) the number of cancers diagnosed and standardized incidence ratio (SIR) for pancreatobiliary and other cancers during the observational period and (2) prognosis after diagnosis of AIP and IgG4-SC using standardized mortality ratio (SMR).

RESULTS

This study included 201 patients with AIP and IgG4-SC. The mean follow-up period was 5.7 years. Seven cases of pancreatic cancer were diagnosed, and the SIR was 8.11 (95% confidence interval [CI]: 7.29-9.13). Three cases of bile duct cancer were diagnosed, and the SIR was 6.89 (95% CI: 6.20-7.75). The SMR after the diagnosis of AIP and IgG4-SC in cases that developed pancreatobiliary cancer were 4.03 (95% CI: 2.83-6.99).

CONCLUSIONS

Patients with autoimmune pancreatitis and IgG4-SC were associated with a high risk of pancreatic and bile duct cancer. Patients with AIP and IgG4-SC have a worse prognosis when they develop pancreatobiliary cancer.

[Histopathologic diagnosis of solid and cystic pancreatic lesions with a focus on ductal adenocarcinoma : A vademecum for daily practice]

Pancreas pathology is constantly evolving and can present various challenges for pathologists. This paper is focused on providing helpful hints for daily routine diagnostics. During histopathological analysis of pancreas biopsies, pancreatic ductal adenocarcinoma must be distinguished not only from other solid neoplasms, but especially from its mimicker, autoimmune pancreatitis. This can be achieved by a systematic workup following clear diagnostic criteria. When analyzing samples from cystic pancreatic lesions, mucin-producing neoplasms must be detected due to their role as pancreatic cancer precursors; molecular analyses can help considerably with their detection and distinction. During frozen section examination, evaluation of the pancreatic neck margin and analysis of unclear lesions of the liver are two important tasks, which are explained further in this article. A special challenge is the evaluation of neoadjuvant treated pancreatic cancer, which requires a detailed macroscopic and microscopic workup. Finally, current advances in precision oncology and emerging approaches for pancreatic cancer within this field are discussed. With the advancement of technical possibilities and their increasingly broad implementation, the classification systems in pancreatic pathology will continue to gain in complexity, but also in accuracy.

Autoimmune pancreatitis: A bibliometric analysis from 2002 to 2022

Background/Objectives

Autoimmune pancreatitis (AIP) is a distinct form of pancreatic inflammatory disease that responds well to glucocorticoid therapy. Knowledge on AIP has rapidly evolved over the past two decades. Based on bibliometric analysis, this study aimed to assess the research status of AIP over the past two decades and determine the research focus and emerging topics.

Methods

AIP-related publications published between January 1, 2002, and June 6, 2022, were retrieved from the Web of Science Core Collection. Bibliometric data were analyzed using HisCite, VOSviewer, CiteSpace, and bibliometrix package. Annual output, leading countries/regions, active institutions and authors, core journals and references, and keywords of AIP were evaluated.

Results

Overall, 1,772 publications were retrieved from 501 journals by 6,767 authors from 63 countries/regions. Japan published articles on AIP the most (n=728, 41.1%), followed by the United States (n=336, 19%), Germany (n=147, 8.3%), China (n=127, 7%), and Italy (n=107, 6%). The top three most prolific authors were Terumi Kamisawa from Tokyo Metropolitan Komagome Hospital (n=117), Kazuichi Okazaki from Kansai Medical University (n=103), and Shigeyuki Kawa from Matsumoto Dental University (n=94). Pancreas was the most productive journal regarding AIP research (n=95), followed by the Journal of Gastroenterology (n=67), Internal Medicine (n=66), Pancreatology (n=63), and World Journal of Gastroenterology (n=62). "Diagnosis" was the most mentioned keyword. "Risk," "malignancy," "outcome," "22-gauge needle," and "fine-needle aspiration" were recognized as emerging topics.

Conclusion

Japan was the leading country in AIP research. Research papers were mainly published in specialized journals. Diagnosis was the research focus. Long-term outcomes and pancreatic tissue acquisition were recognized as research frontiers for AIP.

The M-ANNHEIM-AiP-Activity-Score is useful for predicting relapse in patients with type 1 autoimmune pancreatitis

BACKGROUND/OBJECTIVES

Proper assessment of disease activity and prediction of relapse are crucial for the management of autoimmune pancreatitis (AIP). The M-ANNHEIM-AiP-Activity-Score (MAAS) has been proposed to determine disease activity and predict relapse in German and Swedish patients with AIP. MAAS is calculated using six categories: pain report, pain control, exocrine insufficiency, endocrine insufficiency, imaging, and complications. This study aimed to clarify the usefulness of MAAS to predict relapse in Japanese patients with type 1 AIP.

METHODS

We retrospectively analyzed 117 patients with type 1 AIP undergoing initial and maintenance steroid treatments at our institute between April 2006 and March 2021. AIP was diagnosed according to the Japanese Diagnostic Criteria for AIP 2018. We examined the association of MAAS with relapse during and after maintenance treatment.

RESULTS

MAAS (median, 8 points) at the start of the initial treatment was reduced after treatment (median, 4 points; P < 0.001). A MAAS ≥11 points at the start of the initial treatment was associated with relapse. The initial treatment-induced reduction of MAAS<60% was more frequent in patients with relapse (75.0%) than in patients without relapse (37.6%; P = 0.007). MAAS at the start of maintenance treatment was higher for patients with relapse (median, 5 points) than that for patients without relapse (median, 4 points; P = 0.007). MAAS ≥4 points at the start of maintenance treatment was associated with subsequent relapse.

CONCLUSIONS

MAAS is useful for predicting relapse in patients with type 1 AIP undergoing maintenance therapy.