Kito Katsumi, Maeda Toshiharu, Ninomiya Keiko, Sugita Atsuro, Sagawa Teiri, Matsuoka Kinya, Kinoshita Kousei, Hyodo Naoki, Morita Nagisa, Furuya Keizo
Department of Pathology, Ehime Prefectural Central Hospital, 83 Kasuga-cho, Matsuyama, Ehime 790-0024, Japan.
Department of Surgery, Ehime Prefectural Central Hospital, Matsuyama 790-0024, Japan.
Case Rep Pathol. 2014;2014:310829. doi: 10.1155/2014/310829. Epub 2014 Sep 18.
Apocrine carcinoma, which is strictly defined as over 90% of tumor cells showing apocrine differentiation, is a rare variant of breast cancer. Here we report an uncommon case in which apocrine carcinomas developed concurrently in both breasts; in addition, a sarcomatoid spindle cell lesion was coincident in the right breast. Both apocrine carcinomas were immunohistochemically negative for estrogen receptor (ER) and progesterone receptor (PgR), but diffusely positive for androgen receptor (AR), GCDFP-15, and HER2. The presence of intraductal components in bilateral carcinomas and the absence of lymph node metastasis suggested that they were more likely to be individual primary lesions rather than metastatic disease. The spindle cell lesion showed a relatively well-circumscribed nodule contiguous with the apocrine carcinoma. HER2 oncoprotein overexpression was observed not only in the apocrine carcinoma, but also in the spindle cell lesion. Since the spindle cell component was intimately admixed with apocrine carcinoma and had focal cytokeratin expression, we diagnosed it as metaplastic spindle cell carcinoma, which was originated from the apocrine carcinoma. To our knowledge, this is the first case report of a patient with synchronous bilateral apocrine carcinomas coinciding with metaplastic carcinoma.
大汗腺癌严格定义为超过90%的肿瘤细胞呈现大汗腺分化，是乳腺癌的一种罕见变异类型。在此我们报告一例罕见病例，双侧乳房同时发生大汗腺癌；此外，右侧乳房还伴有一个肉瘤样梭形细胞病变。两个大汗腺癌的雌激素受体（ER）和孕激素受体（PgR）免疫组化均为阴性，但雄激素受体（AR）、GCDFP - 15和HER2呈弥漫性阳性。双侧癌中存在导管内成分且无淋巴结转移提示它们更可能是独立的原发性病变而非转移性疾病。梭形细胞病变表现为与大汗腺癌相邻的边界相对清晰的结节。不仅在大汗腺癌中观察到HER2癌蛋白过表达，在梭形细胞病变中也有发现。由于梭形细胞成分与大汗腺癌紧密混合且有局灶性细胞角蛋白表达，我们将其诊断为化生型梭形细胞癌，起源于大汗腺癌。据我们所知，这是首例同步双侧大汗腺癌合并化生型癌患者的病例报告。
