Tumor-associated Pancreatitis Mimicking Autoimmune Pancreatitis in a Young Male: A Case of Main Duct IPMC

Abstract

We report a rare case of intraductal papillary mucinous carcinoma (IPMC) in a young male who initially presented with imaging findings suggestive of autoimmune pancreatitis (AIP) and was later diagnosed with tumor-associated pancreatitis. Despite symptom resolution with conservative treatment, follow-up imaging revealed a pancreatic tumor. Surgical resection confirmed the presence of IPMC with adenocarcinoma components. This case highlights the importance of excluding malignancy even in young patients with AIP-like features. Given the limited sensitivity of FDG-PET for early stage tumors, adjunctive modalities such as endoscopic ultrasound (EUS) and serial pancreatic juice aspiration cytological examination (SPACE) should be actively considered.

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Cite

BibTeX RIS

BibTeX

@article{kawanishi2026tumorassociated,
  title = {{Tumor-associated Pancreatitis Mimicking Autoimmune Pancreatitis in a Young Male: A Case of Main Duct IPMC}},
  author = {Mariya Kawanishi and Akitoshi Douhara and Koji Ishida and Masato Nakatsuji and Noriyuki Hamato and Kenji Nakagawa and Masahiro Tsutsumi and Toshiya Nakatani},
  journal = {Internal Medicine},
  year = {2026},
  month = aug,
  doi = {10.2169/internalmedicine.6037-25},
  url = {https://www.jstage.jst.go.jp/article/internalmedicine/65/15/65_6037-25/_article},
  note = {CC BY-NC-ND},
}

RIS

TY  - JOUR
TI  - Tumor-associated Pancreatitis Mimicking Autoimmune Pancreatitis in a Young Male: A Case of Main Duct IPMC
AU  - Mariya Kawanishi
AU  - Akitoshi Douhara
AU  - Koji Ishida
AU  - Masato Nakatsuji
AU  - Noriyuki Hamato
AU  - Kenji Nakagawa
AU  - Masahiro Tsutsumi
AU  - Toshiya Nakatani
PY  - 2026
DA  - 2026/08/01
JO  - Internal Medicine
DO  - 10.2169/internalmedicine.6037-25
UR  - https://www.jstage.jst.go.jp/article/internalmedicine/65/15/65_6037-25/_article
AB  - We report a rare case of intraductal papillary mucinous carcinoma (IPMC) in a young male who initially presented with imaging findings suggestive of autoimmune pancreatitis (AIP) and was later diagnosed with tumor-associated pancreatitis. Despite symptom resolution with conservative treatment, follow-up imaging revealed a pancreatic tumor. Surgical resection confirmed the presence of IPMC with adenocarcinoma components. This case highlights the importance of excluding malignancy even in young patients with AIP-like features. Given the limited sensitivity of FDG-PET for early stage tumors, adjunctive modalities such as endoscopic ultrasound (EUS) and serial pancreatic juice aspiration cytological examination (SPACE) should be actively considered.
SN  - 1349-7235
SN  - 0918-2918
ER  -