Evidence map›Paper›PMID 41893955›Full record

ArticleClinical journal of gastroenterology2026

Autoimmune pancreatitis limited to the main pancreatic duct without mass formation.

Kaoruko Kanamaru, Arata Sakai, Takashi Kobayashi, Atsuhiro Masuda, Norimitsu Uza, Takayuki Kodama, Yoshihide Nanno, Takumi Fukumoto, Yuzo Kodama

Abstract readCase Reports
PubMed Full text at PMC Publisher
In one paragraph

Article in Clinical journal of gastroenterology, 2026. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Not yet cited in PubMed.

0numbers the graph read from it
0cells of the map it votes in
0citing papers in PubMed
–field-weighted citation impact
1 · What the graph read from it

What it found

Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.

The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.

2 · The registry

The trial behind it

Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.

Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.

3 · Its place in the literature

Who cites it

0 citing papers in PubMed.

No citing paper in PubMed yet.

4 · The record

Corrections and comments

PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.

5 · Who and what money

Authors and funding

9 authors.

Kaoruko KanamaruDivision of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki- cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.
Arata SakaiDivision of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki- cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan. asakai@med.kobe-u.ac.jp.ORCID http://orcid.org/0000-0003-1072-5243
Takashi KobayashiDivision of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki- cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.
Atsuhiro MasudaDivision of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki- cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.
Norimitsu UzaDivision of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki- cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.
Takayuki KodamaDivision of Molecular and Genomic Pathology, Department of Pathology, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.
Yoshihide NannoDivision of Hepato-Biliary-Pancreatic Surgery, Department of Surgery, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.
Takumi FukumotoDivision of Hepato-Biliary-Pancreatic Surgery, Department of Surgery, Kobe University Graduate School of Medicine, 7-5-2 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.
Yuzo KodamaDivision of Gastroenterology, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki- cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.

Funding

No grant is acknowledged in the PubMed record.

6 · The paper itself

Abstract

We present a rare case of autoimmune pancreatitis (AIP) confined exclusively to the subepithelial layer in the main pancreatic duct (MPD) without associated pancreatic enlargement or mass formation. A 73-year-old man presented with elevated serum pancreatic enzymes and IgG4 levels. Imaging revealed a short-segment MPD stenosis in the body of the pancreas without pancreatic swelling. Endoscopic ultrasonography showed localized periductal thickening of the MPD, raising suspicion of pancreatic carcinoma in situ (CIS). Cytological analysis of pancreatic juice identified atypical cells, prompting surgical resection. Histopathological examination of the resected specimen revealed characteristic features of type 1 AIP, including dense lymphoplasmacytic infiltration, storiform fibrosis, and obliterative phlebitis, which were strictly confined to the subepithelial layer in the MPD. No malignant cells were found, and the surrounding pancreatic parenchyma showed only minimal fibrotic changes. This case may broaden the recognized clinical spectrum of AIP by demonstrating a rare presentation without mass formation or pancreatic swelling, which closely mimicked pancreatic CIS. Further accumulation of cases may enhance our comprehensive understanding of this disease entity.

Indexed as

Autoimmune PancreatitisPancreatic DuctsAgedDiagnosis, DifferentialEndosonographyHumansImmunoglobulin GMaleImmunoglobulin GAutoimmune pancreatitisCarcinoma in situCase reportMain pancreatic duct

Identifiers

PMID41893955
PMCPMC13219219

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Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.