Neutrophil Infiltration and Acinar-ductal Metaplasia Are the Main Pathological Findings in Pembrolizumab-induced Pancreatitis.

Abstract

The histopathological findings of immune checkpoint inhibitor (ICI)-induced pancreatitis have rarely been reported. A 56-year-old man with squamous cell carcinoma of the lung with bone metastasis was being treated with pembrolizumab, an anti-programmed cell death protein-1 antibody. After 13 doses, he was referred to our department due to pancreatitis. Despite characteristic symptoms of acute pancreatitis, imaging findings were similar to those of autoimmune pancreatitis. However, a histological examination showed neutrophil-based inflammatory cell infiltration and acinar-ductal metaplasia. Immunostaining showed CD8-positive T lymphocyte infiltration. This case revealed the characteristic histopathology of pembrolizumab-induced pancreatitis, which was previously poorly understood.

• Authors: Morihisa Hirota, Keigo Murakami, Akinobu Koiwai, Keita Kawamura, Yuki Yoshino, Atsuko Takasu, Ryo Kin, Tomofumi Katayama, Katsuya Endo, Takayuki Kogure, Takayoshi Meguro, Toshiharu Tabata, Kazuhiro Murakami, Kennichi Satoh
• Journal: Internal medicine (Tokyo, Japan) (Intern Med) Vol. 61 Issue 24 Pg. 3675-3682 (Dec 15 2022) ISSN: 1349-7235 [Electronic] Japan
• PMID: 35527030 (Publication Type: Case Reports, Journal Article)

Chemical References

• pembrolizumab

Topics

• Male
• Humans
• Middle Aged
• Pancreatitis (chemically induced, pathology)
• Neutrophil Infiltration
• Acute Disease
• Metaplasia (chemically induced)