Abstract:
Signet-ring stromal tumor (SRST) is a rare ovarian stromal neoplasm characterized by a population of bland signet-ring cells, devoid of mucin or lipid, in a generally cellular fibromatous stroma. Previous reports have described heterogenous immunohistochemical and molecular genetic findings, including occasional nuclear β-catenin expression and/or CTNNB1 mutations. We report 10 ovarian stromal neoplasms originally diagnosed as SRST. All but 1 tumor underwent detailed immunohistochemical analysis (including β-catenin) and 5 of 10 had CTNNB1 mutation analysis performed. All tumors contained a population of morphologically bland signet-ring cells that ranged from 15% to 95% of the neoplasm, characterized by a single large empty intracytoplasmic vacuole, mostly with nuclear indentation. Six of the 10 tumors contained cellular fibroma-like areas, comprising from 10% to 85% of the neoplasm. Three of the 10 tumors were reclassified as microcystic stromal tumor with signet-ring cells on the basis of the microcyst formation and hyalinized stroma, beta-catenin and cyclin D1 nuclear expression and/or CTNNB1 mutation, CD10 staining and largely absent expression of inhibin and calretinin. In the remaining 7 tumors, the diagnosis of SRST remained, constituting the largest series of SRST reported in the literature to date. The results of our study suggest that a subset of tumors diagnosed as ovarian SRST, especially those which show β-catenin nuclear positivity and/or CTNNB1 mutation, likely represent microcystic stromal tumor with variant morphology. We also suggest that at least a subset of SRSTs without evidence of Wnt/β-catenin pathway abnormalities may be related to ovarian fibromas. We discuss the differential diagnosis of ovarian neoplasms containing signet-ring cells.
摘要:
印戒间质瘤(SRST)是一种罕见的卵巢间质肿瘤,其特征是一群温和的印戒细胞,缺乏粘蛋白或脂质,在通常的细胞纤维瘤基质中。以前的报道描述了异质性免疫组织化学和分子遗传学发现,包括偶尔的核β-连环蛋白表达和/或CTNNB1突变。我们报告了10例最初诊断为SRST的卵巢间质肿瘤。除1个肿瘤外,所有肿瘤均进行了详细的免疫组织化学分析(包括β-连环蛋白),10个中的5个进行了CTNNB1突变分析。所有肿瘤都含有一群形态平淡的印戒细胞,占肿瘤的15%至95%。以一个巨大的胞浆内空泡为特征,主要是核压痕。10个肿瘤中有6个含有细胞纤维瘤样区域,占肿瘤的10%至85%。根据微囊肿的形成和透明的基质,将10个肿瘤中的3个重新分类为带有印戒细胞的微囊性间质瘤,β-连环蛋白和细胞周期蛋白D1核表达和/或CTNNB1突变,CD10染色,抑制素和钙视网膜素表达基本缺失。在剩下的7个肿瘤中,SRST的诊断仍然存在,构成了迄今为止文献中报道的最大的SRST系列。我们的研究结果表明,一部分被诊断为卵巢SRST的肿瘤,特别是那些显示β-连环蛋白核阳性和/或CTNNB1突变,可能代表形态变异的微囊性间质瘤。我们还建议,至少没有Wnt/β-catenin通路异常证据的SRST子集可能与卵巢纤维瘤有关。我们讨论了含有印戒细胞的卵巢肿瘤的鉴别诊断。