A case of deciduosis of the appendix
厚生連医誌―Immunological第１６巻 analysis
１号 ８of６〜its
８８origin―
２００７

Case Report

A case of deciduosis of the appendix―Immunological analysis of its origin―
Nagaoka Central General Hospital, Department of Pathology ; Pathologist

Toshihiko Ikarashi
Background : Deciduosis was frequently discovered inmany organs during pregnancy. Appendix was occasionally affected and found as acute abdomen.
We experienced one case and its immunohistochemical study of deciduosis of the appendix wasreported.
Case : The patient was a 34-year-old pregnant woman,presented with signs and symptoms of acute appendicitis in 31-week of gestation. Appendectomy
was performed and showed phregmonous inflammation with perforation. The serosal side becamemarkedly thickened with myxoid change. Histologically, the lesion was characterized by thepresence of multiple, irregularly distributed submesothelial deposits of decidualized cells. Immunohistochemically, the decidualized cells strongly
stained by vimentin and WT 1, consistent with decidual stromal cells. The intercalated gland-like lesions were derived from not heterotopic endometriosis but mesothelial invagination or its inclusions
immunohistochemically.
Conclusion : This tumor was consistent with deciduosisof the appendix.

dix revealed subserosal decidualization with gland-likeconfiguration（Photo 3, 4）．The gland-like lesions wereimmunologically examined if they were derived from endometrial glands. Immunological results were summarized（Table 1, Photo 5），which suggested that these glands
revealed not endometrium but mesothelium of invagination or rests"．Decidual cells were positive for WT 1 andhormonal receptors as eutopic deciduas.
Conclusion
We studied the massive subserosal myxoid change
immunologically. Pseudodecidualized cells were positivefor WT 1 as eutropic decidual cells. Intercalated glandlike lesions were regarded as mesothelial origin rather
than ectopic endometrial one with CD 15, WT 1, and calretinin as immunological mesothelial markers. Consequently deciduosis of the appendix was derived from ectopic decidual reaction of eutopic appendicial or mesoappendicial stroma immunologically. This tumor was consistent with deciduosis of the appendix.
Reference
１．Suster S, Moran CA. Deciduosis of the appendix.
Am J Gastroenterol 1990 ; 85 : 841-5.
２．Ikarashi T et al. Immunohistochemical detection of p
53 in endometrial carcinoma for the prospect of lymphatic permeation and nodal metastasis participating in
the prognosis. Niigata-Ken Koseiren Med J 1998 ; 8 :28-31.

Key Words : deciduosis of the appendix, acute abdomen,pregnancy-associated deciduosis, immunohistochemistry, origin
Background
Several cases of ectopic deciduosis during pregnancy were reported but its histogenesis remained in discussion!．External endometriosis was most compatibleand decidualized cell were derived from ectopic endometrial stromal cells.
In this time we experienced one case of deciduosisof the appendix and reported our immunological analysis
for its origin.

和文抄録症 例 報告

虫垂脱落膜症の１症例 ―起源の免疫組織学的検討―
長岡中央綜合病院、病理部；病理医
五十嵐俊彦

Case
A 34-year-old pregnant woman presented withsigns and symptoms of acute appendicitis in 31-week ofgestation. Appendectomy was performed and showed
phregmonous inflammation with perforation. The serosalside became markedly thickened with myxoid change,swollen in diameter up to 1.5 cm（Photo 1, 2），
Histological findings : Appendix and mesoappen-

背景：脱落膜症は、妊娠中に、様々な臓器に認められる。虫垂脱落膜症は稀に急性腹症として報告される。
症例：虫垂脱落膜症の１症例について経験したので、免疫組織学的検討を加え、その起源について検討した。症例は妊娠３１週の３４才妊婦で、急性化膿性虫垂炎による急性腹症として開腹され、穿― 86 ―

厚生連医誌

第１６巻

１号 ８６〜８８ ２００７

孔を伴う虫垂脱落膜症と診断された。免疫組織学的に、子宮内膜症の関与を認めることは出来なかった。

結論：特発性の虫垂脱落膜症の１症例について報告した。
キーワード：虫垂脱落膜症、急性腹症、妊娠関連性脱落膜症、免疫組織化学、起源

Photo 1 loupe

Photo 4 HE

Photo 2 loupe

Photo 5 calretinin

Photo 3 HE― 87 ―

A case of deciduosis of the appendix―Immunological analysis of its origin―

Table 1 Immunostaining and mucous histochemistry
Reagent against

target cells

peritoneum

gland-likedecidual-likeCD１５（LeuM１）

Hodgkin, mesothelium＋＋

−

CD６
８

monocyte･Mφ

−

−

−

vimentinmesenchyme

−

−

++

desminmuscle−−−HHF−３５muscle

−

−

−

α-SMA

muscle

−

−

−

CD３
４

endothelium･GIST

−

−

−

S１
００nerve

−

−

−

AE−１，
３

epithelium

＋＋

−

CAM５．
２

epithelium＋＋−

Ber-EP４

epithelium＋＋−CEA

epithelium−−−

D２−４０mesothelium

−

−

−

calretinin

mesothelium＋＋−

WT１

mesothelium＋＋＋

c-kit

gastrointestinal stromal tumor

−

−

−

HPL

chorioepithelium-related

−

−

−

ER

estrogen receptor＋＋＋

PgR

progesterone receptor＋＋＋

AlB pH２．
５mucin＋＋＋

AlB pH１．
０mucinPASmucin･glycogenmucicarmine

mucin

GIST : gastrointestinal stromal tumor― 88 ―＋＋＋

glycogenglycogenglycogen−−−