Objective: Investigate the clinicopathological features for secretory carcinoma of breast (SCB). Methods: The clinical data of 3 SCB cases were collected, immunohistochemical staining was performed by the streptavidin-peroxidase (SP) method to test the expression of the antibodies: ER, PR, HER-2, Ki-67, S100, CK5/6, p63, SMA, calponin, GCDFP-15, and EGFR. Fluorescence in situ hybridization (FISH) was used to detect the ETV6-NTRK3 gene fusion. Results: ER was focal weakly positive in case 1 and case 2 (about 5%) , and negative in case 3. PR was focal weakly positive in case 1 (about 5%) and completely negative in case 2 and case 3. Three cases showed that HER-2, SMA, calponin, GCDFP-15 were negative, while S100, CK5/6, EGFR were diffuse strongly positive. The proliferation index was nearly 15% in case 1 and case 2, and 10% in case 3. p63 was negative in mostly tumor cells of case 1, and focal positive expression in the nucleus and cytoplasm. In case 2, p63 was completely negative. However, p63 was observed positive in the cytoplasm as well as some secretory material in case 3. ETV6-NTRK3 gene fusion detection by FISH was positive in all cases. Conclusions: SCB is a rare low grade triple-negative breast cancer with the unique pathomorphologic features, while its recurrent t (12; 15) (p13; q25) translocation resulting in ETV6 -NTRK3 gene fusion. It has the indolent clinical behavior and good prognosis.
目的： 探讨乳腺分泌性癌(SCB)的临床病理特征。 方法： 收集3例SCB的临床资料，采用免疫组化SP法检测雌激素受体(ER)、孕激素受体(PR)、人表皮生长因子受体2(HER－2)、Ki－67、S100、CK5/6、p63、平滑肌肌动蛋白(SMA)、钙调理蛋白(calponin)、巨囊性病液体蛋白15(GCDFP－15)和表皮生长因子受体(EGFR)等的表达情况，采用荧光原位杂交技术检测ETS变异基因6－神经酪氨酸激酶受体3(ETV6－NTRK3)融合基因。 结果： 例1和例2 ER(局灶弱＋，约5%)，例3 ER(－)；例1 PR(局灶弱＋，约5%)，例2和例3 PR (－)；3例均HER－2(－)，S100(弥漫强＋)，CK5/6(＋)，SMA(－)，calponin(－), GCDFP－15(－)，EGFR(＋)。例1 Ki－67指数为15%，例2为15%，例3为10%。例1大部分肿瘤细胞p63(－)、局灶区域细胞核(＋)、局灶区域细胞质(＋)；例2 p63(－)，例3肿瘤细胞p63染色细胞质(＋)、部分分泌物阳性着色。3例均成功检测出ETV6－NTRK3融合基因。 结论： SCB是一种罕见的低级别特殊类型三阴性乳腺癌，具有独特的病理形态学特征，分子遗传学上具有特征性t(12；15) (p13；q25)平衡易位，产生ETV6－NTRK3融合基因，临床过程惰性，预后好。.
Keywords: ETS variant gene 6-neurotrophic tyrosine receptor kinase 3 gene; Pathology; Secretory carcinoma, breast.