背景:粘液性囊腺癌(MCA)是一种非常罕见的乳腺癌形式,最早于1998年被描述。只有33例原发性MCA,包括我们目前的情况,到目前为止,已经有报道。因此,它的分子特征,预后和治疗方案知之甚少。这里,我们描述了一个不太常见的MCA,详细说明其分子特征,讨论主要的鉴别诊断,并对文献进行简要回顾。
方法:一名59岁的女性患者出现乳房肿块,乳房X线照相术显示结节明确。芯针穿刺活检(CNB)发现数个病灶为高柱状细胞,分层,黏液分泌丰富,建议切除作为最终诊断。切除的标本显示出不同大小的腔,没有周围的肌上皮细胞。这些洞富含粘液,细胞核位于细胞的底部,含有细胞内粘液。免疫组织化学分析显示它是三阴性乳腺癌(TNBC)。下一代测序(NGS)揭示了PIK3CA中的致病性突变,KRAS,MAP2K4,RB1,KDR,PKHD1,TERT,和TP53基因。做出了MCA的诊断。到目前为止,患者已随访108个月,没有复发或转移的迹象。
结论:我们的研究显示了108个月随访后无复发或转移倾向的MCA病例的基因谱,文献的回顾有助于我们更好地理解临床,病理性,和这种肿瘤的分子特征。
BACKGROUND: Mucinous cystadenocarcinoma (MCA) is a very rare form of breast cancer that was first described in 1998. Only 33 cases of primary MCA, including our present case, have been reported thus far. As a consequence, its molecular features, prognosis and treatment regimen are poorly known. Here, we describe a less common presentation of MCA, detail its molecular features, discuss the major differential diagnosis, and provide a brief review of the literature.
METHODS: A 59-year-old woman presented with a breast lump in which mammography showed a well-defined nodule. Core needle biopsy (CNB) revealed several lesions lined by tall columnar cells with stratification and abundant mucinous secretion; excision was recommended for final diagnosis. The resected specimens showed cavities of different sizes without surrounding myoepithelial cells. The cavities were rich in mucus, and the nuclei were located at the base of the cells, containing intracellular mucus. Immunohistochemical analysis revealed that it was triple-negative breast cancer (TNBC). Next-generation sequencing (NGS) revealed pathogenic mutations in the PIK3CA, KRAS, MAP2K4, RB1, KDR, PKHD1, TERT, and TP53 genes. A diagnosis of MCA was rendered. The patient has been followed up for 108 months to date and showed no signs of recurrence or metastasis.
CONCLUSIONS: Our study presents the gene profile of an MCA case with no recurrence or metastatic tendency after 108 months of follow-up, and a review of the literature helps us better understand the clinical, pathologic, and molecular features of this tumor.