背景:伴脉络膜癌的浸润性乳腺癌(IBC-CP)极为罕见,其分子基础尚不清楚。脉络膜癌模式的特征是在出血性背景下,多核合胞滋养层细胞样细胞在单型肿瘤细胞簇周围双相排列,以及β-人绒毛膜促性腺激素(β-hCG)的表达。由于组织学相似性,IBC-CP与乳腺转移性绒毛膜癌(MC-B)的区别很困难。
方法:基于文献综述和我们自己的案例,我们分析了IBC-CP患者(n=17)和MC-B患者(n=8)的临床病理学差异.此外,在我们的IBC-CP案例中,对绒毛膜癌和浸润性乳腺癌(IBC)成分进行了下一代测序(NGS)比较分析.
结果:与MC-B患者相比,IBC-CP患者年龄较大(p<0.001),既往有妊娠滋养细胞疾病/妊娠/流产史(p=0.001)和远处转移史(p=0.005)的发生率较低.我们的案子,一名49岁的女性患者,右乳房和腋下有肿块。新辅助化疗后,根治性乳房切除术发现一个8.5厘米大小的肿瘤。微观上,在单个核肿瘤细胞周围观察到多核合胞体滋养层样细胞,并伴有出血和坏死。一些肿瘤细胞显示β-hCG免疫阳性,与IBC-CP兼容。NGS结果显示绒毛膜癌和IBC成分中TP53基因外显子5的错义突变。同时,PTEN基因的拷贝数丢失仅在绒毛膜癌成分中被发现。
结论:目前的IBC-CP病例是TP53突变的三阴性乳腺癌。PTEN基因可能与绒毛膜癌的分化有关。必须获得病史以排除转移性病变。
BACKGROUND: Invasive breast carcinoma with a choriocarcinomatous pattern (IBC-CP) is extremely rare, and its molecular basis is yet unclear. The choriocarcinomatous pattern is characterized by the biphasic arrangement of multinucleated syncytiotrophoblast-like cells around clusters of monotypic tumor cells in a hemorrhagic background, along with β-human chorionic gonadotropin (β-hCG) expression. The differentiation of IBC-CP from metastatic choriocarcinoma of the breast (MC-B) is difficult due to the histologic similarity.
METHODS: Based on a literature review and our own
case, the clinicopathologic differences between IBC-CP patients (n = 17) and MC-B patients (n = 8) were analyzed. Moreover, in our
case of IBC-CP, next-generation sequencing (NGS) comparative analysis was conducted for both choriocarcinomatous and invasive breast carcinoma (IBC) components.
RESULTS: Compared to the MC-B patients, the IBC-CP patients were older (p < 0.001) and less frequently had past histories of gestational trophoblastic disease/pregnancy/abortion (p = 0.001) and distant metastases (p = 0.005). Our
case, a 49-year-old female patient, presented with masses in the right breast and axilla. Following neoadjuvant chemotherapy, a radical mastectomy found an 8.5-cm-sized tumor. Microscopically, multinucleated syncytiotrophoblast-like cells were observed around mononuclear tumor cells with hemorrhage and necrosis. Some tumor cells showed β-hCG immunopositivity, which was compatible with IBC-CP. NGS results showed a missense mutation in exon 5 of the TP53 gene in both the choriocarcinomatous and IBC components. Meanwhile, copy number loss in the
PTEN gene was only identified in the choriocarcinomatous components.
CONCLUSIONS: The present IBC-CP case is triple-negative breast cancer with TP53 mutation. The
PTEN gene may be associated with choriocarcinomatous differentiation. Obtaining a medical history is mandatory to exclude metastatic lesions.