Download Ｇastric adenocarcinoma of fundic gland type (GA

Ｇastric adenocarcinoma of fundic gland type
(GA-FG)．
Ａ ｎｅｗ entity
1. Process of establishing this entity and
clinicopathological features of GA-FG
2. Progressive variant of GA-FG
3. Genetic events of GA-FG
4. Differential diagnosis
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Differential diagnosis
• (Atypical) chief cell hyperplasia
• Fundic gland polyp
• Adenoma of pyloric gland type
• Carcinoid tumor
• Parietal cell carcinoma
• Oncocytic adenocarcinoma
Chief cell hyperplasia ?
•Müller-Höcker J, et al.
Chief cell proliferation of the gastric mucosa mimicking early
gastric cancer: an usual variant of fundic gland polyp.
Virchow Archiv 442: 496-500, 2003.
•Matsukawa A, et al.
Chief cell hyperplasia with structural and nuclear atypia: a
variant of fundic gland polyp.
Pathol Res Pract 200: 817-821, 2005
The lesions in these reports are the same as
ACFG
ARTICLE IN PRESS
Pathology – Research and Practice 200 (2005) 817–821
www.elsevier.de/prp
TEACH I NG CASE
Chief cell hyperplasia with structural and nuclear atypia:
a variant of fundic gland polyp
Akihiro M atsukawaa, , Ryoichi K uranob, Takahiro Takemotoc,
M otoko K agayamaa, Takaaki I toa
The cytological feature
is the same as the
adenocarcinoma of
fundic gland type
Differential diagnosis
• (Atypical) chief cell hyperplasia
• Fundic gland polyp
• Adenoma of pyloric gland type
• Carcinoid tumor
• Parietal cell carcinoma
• Oncocytic adenocarcinoma
Fundic gland polyp (FGP)
• FGP is mainly composed of mature chief and parietal
cells with scattered mucous cells.
• Cytological feature of FGP is similar to GA-FG.
• Lack of cytological and architectural atypa in FGP is
different from GA-FG.
Pyloric gland adenoma (PGA)
PGA is positive for MUC6, which is the same as AG-FG, but is
usually negative for pepsinongen I and H+/K+-ATPase.
MUC6
Differential diagnosis
• (Atypical) chief cell hyperplasia
• Fundic gland polyp
• Adenoma of pyloric gland type
• Carcinoid tumor
• Parietal cell carcinoma
• Oncocytic adenocarcinoma
A case submitted to some medical journal as
“A case of gastric carcinoid”
GA-FG is sometimes misdiagnosed as carcinoid
Diagnosed as carcinoid by immunohistochemistry
GA-FG can be misdiagnosed
as carcinoid only by
immunohistochemical results.
Chromgranin A (CG-A)(-)
CD５６
(+)
GA-FG is negative for CG-A.
Synaptophysin (+)
(a)
(b)
Histological features a little bit similar to carcinoid
(c)
Carcinoid is negative for pepsinogen I and MUC6
Pepsinogen I
（＋）
MUC6
（＋）
Differential diagnosis
• (Atypical) chief cell hyperplasia
• Fundic gland polyp
• Adenoma of pyloric gland type
• Carcinoid tumor
• Parietal cell carcinoma
• Oncocytic adenocarcinoma
Parietal cell carcinoma of gastric cardia:
immunophenotype and ultrastructure.
Only one case was reported, confirming parietal
cell differentiation by H+/K+-ATPase positivity
Yang GY, et al. Uitrastruct Pathol. 227:87-94, 2003.
Oncocytic adenocarcinoma of the stomach:
Parietal cell carcinoma.
So-called “Parietal cell carcinomas”were oncocytic
adenocarcinoma, which were positive for
antimitochondrial antibody MAB 1273
Takubo K, et al. Am J Surg Pathol. 26:458–465, 2002.
Summary
• Gastric adenocarcinoma of fundic gland type (GAFG) is a new entity having distinct
clinicopathological features.
• GA-FG is not associated with H, plyori infection.
• GA-FG was originally reported as low-grade
malignancy, however, a progressive variant with
aggressive biological behaviors, fundic gland
mucosal type, has been found.
• Carcinogenesis and/or progression of GA-FG is
associated with Wnt/β-catenin signalling pathway
and GNAS mutation in part.
• Further study with collecting more cases is needed
for clarifying its natural history.
Thank you very much for your kind
attention