Chae Yang Seok, Kim Hyunchul
Department of Pathology, Korea University Medical Center Anam Hospital Seoul, Republic of Korea.
Department of Pathology, Hallym University Dongtan Sacred Heart Hospital Hwaseong-si, Gyeonggi-do, Republic of Korea.
Int J Clin Exp Pathol. 2021 Jan 1;14(1):126-132. eCollection 2021.
Histopathologic diagnosis of thyroid lesions is sometimes difficult and may require the assistance of immunohistochemistry. Currently-used immunohistochemical biomarkers share the weakness of staining both papillary thyroid carcinoma and other non-papillary thyroid lesions. We examined NPC2 as an immunohistochemical marker in various thyroid lesions to determine the subcellular localization of the immunohistochemistry signal and evaluated the value of NPC2 as a diagnostic marker of papillary thyroid carcinoma. NPC2 immunostaining was performed on various thyroid tumors and tumor-like lesions. The immunostaining revealed significantly different patterns for papillary carcinomas and the other lesions. Papillary carcinomas exhibited moderate to strong granular cytoplasmic staining, often with basal membranous accentuation. In contrast, the other lesions showed mostly weak cytoplasmic staining, often with apical membranous accentuation. The subcellular localization of NPC2 provided insight into contrasting histopathologic morphology and reversed cellular polarity between the papillary patterns of papillary carcinomas and the follicular patterns of non-papillary carcinoma lesions. The diagnostic characteristics of NPC2 immunohistochemistry for non-follicular papillary carcinomas versus non-papillary carcinoma lesions were a sensitivity of 97.3%, specificity of 96.9%, positive predictive value of 94.7%, and negative predictive value of 98.4%. Significant differences were present between the two staining patterns in papillary carcinoma relative to mean age, nodal metastasis, and follicular and non-follicular variants ( = 0.02, = 0.03, and = 0.000, respectively). In conclusion, our evaluation of the subcellular localization of NPC2 using immunohistochemistry demonstrated possible value of NPC2 as a biomarker and provided insight into the morphologic characteristics of papillary carcinoma.
甲状腺病变的组织病理学诊断有时很困难，可能需要免疫组织化学的辅助。目前使用的免疫组织化学生物标志物都存在甲状腺乳头状癌和其他非乳头状甲状腺病变均呈阳性染色的缺点。我们检测了NPC2作为各种甲状腺病变中的一种免疫组织化学标志物，以确定免疫组织化学信号的亚细胞定位，并评估NPC2作为甲状腺乳头状癌诊断标志物的价值。对各种甲状腺肿瘤和肿瘤样病变进行了NPC2免疫染色。免疫染色显示乳头状癌和其他病变的模式有显著差异。乳头状癌表现为中度至强的颗粒状细胞质染色，常伴有基底膜强化。相比之下，其他病变大多表现为弱细胞质染色，常伴有顶端膜强化。NPC2的亚细胞定位有助于深入了解对比鲜明的组织病理学形态，以及甲状腺乳头状癌的乳头状模式与非乳头状癌病变的滤泡状模式之间细胞极性的反转。NPC2免疫组织化学对非滤泡性乳头状癌与非乳头状癌病变的诊断特征为：敏感性97.3%，特异性96.9%，阳性预测值94.7%，阴性预测值98.4%。在乳头状癌中，两种染色模式在平均年龄、淋巴结转移以及滤泡性和非滤泡性变体方面存在显著差异（分别为=0.02、=0.03和=0.000）。总之，我们通过免疫组织化学对NPC2亚细胞定位的评估证明了NPC2作为一种生物标志物的潜在价值，并深入了解了乳头状癌的形态学特征。
