Objective: To investigate the morphology and immunohistochemical (IHC) expression of pseudostratified ependymal tubules in ovarian mature teratoma (MT). Methods: Five cases of ovarian MT with pseudostratified ependymal tubules were collected from Shenzhen Hospital(Futian) of Guangzhou University of Chinese Medicine and the Eighth Affiliated Hospital of Sun Yat-sen University from March 2019 to March 2022. In addition, 15 cases of ovarian MT with monolayer ependymal epithelium from Shenzhen Hospital (Futian) of Guangzhou University of Chinese medicine and seven cases of immature teratoma (IMT) from Hainan Provincial People's Hospital from March 2019 to March 2022 were collected as control. The morphologic characteristics and immunophenotypes of pseudostratified ependymal tubules, monolayer ependymal epithelium, and primitive neural epithelial tubules were observed and compared by H&E stain and IHC expression pattern of genes related to the differentiation status of neuroepithelium, namely SALL4, Glypican3, nestin, SOX2, Foxj1, and Ki-67. Results: Mean age of the five patients of ovarian MT with pseudostratified ependymal tubules was 26 years (range from 19 to 31 years). Two tumors were located in the left ovary and three in the right. All five cases were excised, and clinical follow-up was available (mean follow-up 1.5 years; range 0.5 to 3 years). No recurrence was noted in any cases. The pseudostratified ependymal tubules of ovarian MT, which were lined with columnar or oval epithelia up to 4-6 layers, were morphologically similar to the primitive neuroepithelial tubules of IMT and different from monolayer ependymal epithelium of ovarian MT. By immunohistochemistry, SALL4 and Glypican3 were negative, Foxj1 was positive and Ki-67 index was lower in the pseudostratified ependymal tubules and the monolayer ependymal epithelium of ovarian MT. However, the primitive neuroepithelial tubules of IMT showed variably expression of SALL4 and Glypican3, were negative for Foxj1 and high Ki-67 index. All the above three groups expressed nestin and SOX2. Conclusions: The pseudostratified ependymal tubules of ovarian MT, which have morphological similarities to the primitive neuroepithelial tubules of IMT, are similar to the monolayer ependymal epithelia of the MT in immunophenotype. IHC assessment of Foxj1 and Ki-67 is helpful to differentiate the pseudostratified ependymal tubules of ovarian MT from the primitive neuroepithelial tubules of IMT.
目的： 探讨卵巢成熟性畸胎瘤（mature teratoma，MT）的假复层室管膜小管的形态和免疫组织化学表达。 方法： 收集广州中医药大学深圳医院（福田）、中山大学附属第八医院2019年3月至2022年3月伴有假复层室管膜小管的MT病例5例，另收集广州中医药大学深圳医院（福田）2019年3月至2022年3月伴有单层室管膜上皮的MT病例15例及海南省人民医院2019年3月至2022年3月未成熟性畸胎瘤（immature teratomam，IMT）7例作为对照。通过HE染色以及检测和神经上皮分化状态相关基因的免疫组织化学表达，即SALL4、Glypican3、巢蛋白、SOX2、Foxj1、Ki-67的表达，比较观察假复层室管膜小管和单层室管膜上皮、原始神经上皮小管的形态学特点及免疫表型。 结果： 伴有假复层室管膜小管的MT 5例，平均年龄26（19~31）岁，左卵巢2例，右卵巢3例，肿物切除后随访0.5~3年，平均1.5年，均无瘤生存。MT的假复层室管膜小管衬覆柱状或卵圆形上皮，层次可达4~6层，形态学和IMT的原始神经上皮小管较相似，不同于MT的单层室管膜上皮。MT的假复层室管膜小管、MT的单层室管膜上皮不表达SALL4、Glypican3，表达Foxj1，不表达Ki-67；IMT的原始神经上皮小管SALL4、Glypican3表达不定，不表达Foxj1，表达Ki-67。以上3组均表达巢蛋白和SOX2。 结论： MT的假复层室管膜小管在形态学上和IMT的原始神经上皮小管较相似，在免疫表型上和MT的单层室管膜上皮较一致。Foxj1、Ki-67的联合应用，有助于鉴别MT的假复层室管膜小管和IMT的原始神经上皮小管。.