Background: Seromucinous borderline tumor (SMBT) is a rare neoplasm which was newly defined in the 2014 WHO classification. Although the clinical and histopathological characteristics of SMBT have been well described, its cytological characteristics have not. We recently experienced 2 cases of SMBT which were defined by cytological findings of ascites. Case Presentation: Case 1 was a 65-year-old Japanese woman. Preoperative imaging studies revealed abundant ascites and a cystic tumor, with a solid component measuring 13 cm on the left ovary. Radical surgery was performed during the intraoperative diagnosis of ovarian borderline tumor, made by histological examinations of frozen tumor sections. The cytological smears of preoperatively and intraoperatively collected ascites showed many atypical cells resembling reactive mesothelial cells. Alcian-blue staining of cell block sections revealed intracytoplasmic mucin, and the results of immunohistochemistry were consistent with SMBT. The final pathological diagnosis of tumor was SMBT. Case 2 was a 28-year-old Japanese woman. Preoperative imaging studies revealed a small amount of ascites and cystic tumors with solid components in the bilateral ovaries. She initially underwent fertility preservation surgery. SMBT was suspected by cytological examination of smears of intraoperatively collected ascites and the findings of cell block. She underwent additional radical surgery based on a final pathological diagnosis of SMBT. Conclusion: In our experience, the tumor cells of SMBT in ascites mimicked reactive mesothelial cells. The nuclear atypia of SMBTs was intermediate between that of reactive mesothelial cells and serous carcinoma. The immunohistochemistry and mucin staining using cell block were very helpful for facilitating the cytodiagnosis of SMBT.
Acta Cytologica

中文翻译：

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腹水卵巢浆液性交界性肿瘤细胞学表现：附2例报告

背景：浆液性交界性肿瘤（SMBT）是一种罕见的肿瘤，在 2014 年 WHO 分类中被新定义。尽管 SMBT 的临床和组织病理学特征已经得到很好的描述，但其细胞学特征还没有。我们最近经历了 2 例由腹水细胞学检查结果定义的 SMBT。案例介绍：病例 1 是一名 65 岁的日本女性。术前影像学检查显示大量腹水和囊性肿瘤，左侧卵巢有一个 13 cm 的实性成分。通过冷冻肿瘤切片的组织学检查，在术中诊断卵巢交界性肿瘤时进行根治性手术。术前和术中收集的腹水细胞学涂片显示许多类似反应性间皮细胞的非典型细胞。细胞块切片阿尔新蓝染色显示胞浆内粘蛋白，免疫组化结果与SMBT一致。肿瘤最终病理诊断为SMBT。病例2是一名28岁的日本女性。术前影像学检查显示双侧卵巢有少量腹水和囊性肿瘤，伴实性成分。她最初接受了生育保护手术。通过对术中收集的腹水涂片和细胞块的发现进行细胞学检查，怀疑 SMBT。根据 SMBT 的最终病理诊断，她接受了额外的根治性手术。结论：根据我们的经验，腹水中 SMBT 的肿瘤细胞模拟了反应性间皮细胞。SMBT 的核异型性介于反应性间皮细胞和浆液性癌之间。使用细胞块进行免疫组化和粘蛋白染色对促进SMBT的细胞诊断非常有帮助。
细胞学学报