Type 3 Autoimmune Pancreatitis: What Do We Know So Far?

Area of Science:

• Oncology
• Immunology
• Gastroenterology

Background:

• Immune checkpoint inhibitors (ICIs) are increasingly used in cancer therapy, leading to more immune-related adverse events (irAEs).
• Autoimmune pancreatitis type 3 (AIP-3) is a rare irAE with pancreatic injury, presenting with variable features and diagnostic challenges.
• Existing data on AIP-3 are limited, often from small retrospective studies with low-quality evidence.

Purpose of the Study:

• To provide a comprehensive review of current knowledge on AIP-3.
• To discuss the epidemiology, etiopathogenesis, clinical presentations, diagnosis, and treatment of AIP-3.
• To highlight the uncertainties in AIP-3 diagnosis and management, particularly regarding glucocorticosteroids (GCS).

Main Methods:

• This study is a narrative review of recent evidence.
• It synthesizes information from existing literature on AIP-3.
• The review covers epidemiology, pathogenesis, clinical aspects, diagnosis, and treatment.

Main Results:

• AIP-3 is a rare but significant irAE associated with ICI therapy.
• Diagnosis of AIP-3 is complex, with no universally accepted criteria.
• Current management strategies, including GCS, have uncertain efficacy, and clear guidelines are absent.

Conclusions:

• There is a need for standardized diagnostic criteria for AIP-3.
• Further research is required to establish optimal therapeutic strategies and management guidelines for AIP-3.
• Isolated hyperlipasemia alone is insufficient for diagnosing AIP-3 in patients on ICI therapy.