Sclerosing adenosis of mastopathy should be differentiated from scirrhous carcinoma
厚生連医誌
in preoperative
第１６巻histopathological
１号 １３０〜１３diagnosis
１ ２００７

Invention Report

Sclerosing adenosis of mastopathy should be differentiatedfrom scirrhous carcinoma in preoperative histopathologicaldiagnosis
Nagaoka Central General Hospital, Department of Pathology ; Pathologist

Toshihiko Ikarashi
Sclerosing adenosis of breast was frequently misdiagnosed as scirrhous carcinoma in small pathological
specimens and followed an unnecessary treatment against
advanced malignancy. Benign lesions including sclerosing
adenosis revealed the preservation of normal configurationof myoepithelium, so-called as two-cell-pattern, whichmalignant lesions including scirrhous carcinoma lost contrastingly. It was, therefore, very important to identify thismyoepithelium to differentiate benignancy from malignancy. To decrease these troubles we recommended immunohistochemistry to confirm the two-cell-pattern as benignancy with the reagent against myoepithelium of glandulo-ductal elements. In this report we revealed Anti-αsmooth muscle actin（α-SMA）antibody was one of themost available reagents for identifying myoepithelium immunohistochemically.
Key Words : sclerosing adenosis, misdiagnosis, carcinoma of breast, scirrhous carcinoma, immunostain,
α-smooth muscle actin, α-SMA, myoepithelium
A case, 62 y/o, female, was pathologically diagnosed as sclerosing adenosis of right breast, listed as B 06-18903 in our laboratory. Her mammography（MMG）
showed many small calcification and ragiologically diagnosised as Category 3, which meant malignancy could not
be neglected. For preoperative final diagnosis the coreneedle biopsy were done and 9 specimens were obtained,
consisted of 4 samples from calcified areas and 5 samples
from non-calcified ones. They were pathologically adequate samples because two specimens had microcalcification, pointed out on MMG. Most specimens showed sclerosing atrophy and few specimens revealed sclerosing
adenosis and ductal hyperplasia（Fig. 1）.
We performed immunostaining examination onsclerosing adenosis to confirm its myoepithelium as be-nignancy !. Our immunohistochemical results was listed
in Table 1：! inner ductal or glandular epithelium waspositive for AE-1,3 and CAM 5.2 of cytokeratins as epithelial markers（Fig. 2, 3），" basal myoepithelium wasstained by both the above epithelial reagents（Fig. 2, 3）
and myogenic ones（Fig. 4-6）
. α-SMA reagent was very
useful to confirm myoepithelium as benignancy.
References :１．
Ikarashi T. Immunohistochemical application of cytokeratins（＃4 and #17 of Moll's classification），S-100β, and α-smooth muscle actin（α-SMA）as markers of
myoepithelial cells to differentiate well differentiated adenocarcinoma of prostate from their related borderline malignancies. Niigata-Ken Koseiren Med J 1998；8：38-43.

和文抄録
小さな工夫
術前組織検査において、乳腺症の硬化性腺症は硬癌と明確に鑑別されなければならない
長岡中央綜合病院、病理部；病理医
五十嵐 俊彦
乳腺症の１亜型である硬化性腺症は、術前の小さな標本においては、しばしば、硬癌と誤って病理組織診断される。予防の為には、上皮細胞層と筋上皮細胞層による２層構造の保持を確認して、良性の硬化性腺症であると診断することが大切である。その為には、筋上皮細胞同定の為の、α 平滑筋アクチンに対する免疫組織学的検査が有効であった。
キーワード： 硬化性腺症、誤診、乳癌、硬癌、免疫染色、α-smooth muscle actin, α-SMA，筋上皮― 130 ―厚生連医誌

第１６巻

１号 １３０〜１３１ ２００７Table 1 Immunostaining result
reagent

reactionepithelium

basal myoepithelium

＋＋

CAM５．
２＋＋

CD１
０−±αSMA−＋

AE−１，３Fig.1 HE

Fig.4 CD 10

Fig.2 AE-１，３Fig.5 CD 10

Fig.3 CAM５．
２

Fig.6 αSMA

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