Broggi Giuseppe, Farina Jessica, Barresi Valeria, Certo Francesco, Barbagallo Giuseppe Maria Vincenzo, Magro Gaetano, Caltabiano Rosario
Department of Medical and Surgical Sciences and Advanced Technologies "G.F. Ingrassia," Anatomic Pathology, University of Catania.
Department of Neurological Surgery, Policlinico "G. Rodolico-S. Marco" University Hospital, Catania.
Appl Immunohistochem Mol Morphol. 2025 May 1;33(3):160-163. doi: 10.1097/PAI.0000000000001246. Epub 2025 Jan 27.
The histologic differential diagnosis between intracranial hemangioblastoma (HB) and metastatic clear cell renal cell carcinoma may be challenging, especially considering that both tumors exhibit clear cell morphology and can be associated with vHL mutation and/or Von Hippel-Lindau syndrome. As the execution of immunohistochemical analyses is often mandatory, the expression of PAX8 has been traditionally considered a reliable marker of metastatic clear cell renal cell carcinoma, being consistently negative in intracranial HB. However, as in recent years, some cases of PAX8-positive HBs have been reported in the literature; we studied the expression of this antibody on a series of 23 intracranial HB, showing that about 40% of these tumors may express PAX8 and that this immunoreactivity is often focal and weak. We would like to emphasize that the possibility of a PAX8-positive intracranial HB does exist and must be taken into account by neuropathologists to avoid misdiagnoses; in this regard, a broader immunohistochemical panel also including CD10, Inhibin-α, PAX2, S100, and anti-Renal cell carcinoma (RCC) antibody is highly recommended.
颅内血管母细胞瘤（HB）与转移性透明细胞肾细胞癌之间的组织学鉴别诊断可能具有挑战性，尤其是考虑到这两种肿瘤均表现出透明细胞形态，并且可能与VHL突变和/或冯·希佩尔-林道综合征相关。由于免疫组织化学分析的实施通常是必要的，PAX8的表达传统上被认为是转移性透明细胞肾细胞癌的可靠标志物，在颅内HB中始终为阴性。然而，近年来，文献中报道了一些PAX8阳性的HB病例；我们研究了该抗体在一系列23例颅内HB中的表达，结果显示约40%的这些肿瘤可能表达PAX8，并且这种免疫反应性通常是局灶性的且较弱。我们想强调的是，PAX8阳性的颅内HB确实存在，神经病理学家必须考虑到这一点以避免误诊；在这方面，强烈建议使用更广泛的免疫组织化学检测组合，其中还包括CD10、抑制素-α、PAX2、S100和抗肾细胞癌（RCC）抗体。
