Autoimmune Pancreatitis: A Review

Area of Science:

• Gastroenterology
• Immunology
• Oncology

Background:

• Autoimmune pancreatitis (AIP) is a rare inflammatory condition affecting the pancreas.
• It is traditionally classified into two subtypes: Type 1 (lymphoplasmacytic sclerosing pancreatitis, LPSP) and Type 2 (idiopathic duct-centric pancreatitis, IDCP).

Purpose of the Study:

• To describe the emergence and characteristics of a third subtype of AIP.
• To emphasize the importance of recognizing all AIP subtypes for accurate diagnosis and treatment.
• To differentiate ICI-induced pancreatitis from classic AIP subtypes.

Main Methods:

• Literature review of autoimmune pancreatitis and immune checkpoint inhibitor (ICI) related adverse events.
• Analysis of clinical presentations, diagnostic criteria, and treatment outcomes for ICI-induced pancreatitis.
• Comparison of ICI-induced pancreatitis with Type 1 and Type 2 AIP.

Main Results:

• A third subtype of AIP, termed Type 3 or ICI-induced autoimmune pancreatitis, has emerged.
• ICI-induced pancreatitis shares features with classic AIP but has distinct triggers and potential management differences.
• Accurate differentiation is crucial for appropriate patient management.

Conclusions:

• The recognition of ICI-induced pancreatitis (AIP Type 3) expands the understanding of autoimmune pancreatitis.
• Clinicians must be aware of this new entity, especially in patients treated with immune checkpoint inhibitors.
• Further research is needed to fully elucidate the pathophysiology and optimize treatment strategies for ICI-induced pancreatitis.