Department of Dermatology, Venereology and Allergology, HELIOS-Klinikum Hildesheim, Senator-Braun-Allee 33, 31135, Hildesheim, Germany.
Institute of Biometry, Hannover Medical School, Carl-Neuberg-Straße 1, 30625, Hannover, Germany.
Arch Dermatol Res. 2018 May;310(4):329-342. doi: 10.1007/s00403-018-1818-8. Epub 2018 Feb 7.
The histopathologic differentiation between Spitz nevus and melanoma is of particular interest in routine diagnostic procedures of melanocytic tumors. Atypical Spitz nevi are sometimes difficult to distinguish from melanoma. There is still no single criterion that ensures a distinction of melanoma and atypical Spitz nevus. The aim of this study was to reevaluate established and new criteria to differentiate Spitz nevus from melanoma more reliably. We analyzed 25 melanomas with a Breslow index ≥ 1 mm and 18 classical compound Spitz nevi concerning their histopathologic, immunohistochemical and molecular genetic characteristics. Moreover, clinical follow-up data for 5 years were collected. We found statistically significant differences between Spitz nevus and melanoma for the following features: pagetoid spread, atypia, maturation, elastosis, Kamino bodies, p16 expression, and the staining pattern of HMB45. BRAF was positive in 7/21 melanomas and in 1/14 Spitz nevi. Fluorescence in situ hybridization confirmed the histopathologic diagnosis in 36/37 cases. The established clinical, histopathologic, and immunohistochemical criteria to differentiate Spitz nevus and melanoma could be reproduced in our collective. Especially, the expression of p16, BRAF analysis and fluorescence in situ hybridization proved to be helpful tools to improve the differentiation of Spitz nevus and melanoma in our study. Nevertheless, there is-until now-no reliable histopathologic and immunohistochemical parameter which can discriminate Spitz nevus and melanoma with absolute certainty.
在黑素细胞肿瘤的常规诊断程序中，Spitz 痣与黑色素瘤的组织病理学鉴别具有特殊意义。不典型 Spitz 痣有时难以与黑色素瘤区分。目前还没有单一的标准可以确保黑色素瘤和不典型 Spitz 痣的区分。本研究旨在重新评估现有的和新的标准，以更可靠地区分 Spitz 痣和黑色素瘤。我们分析了 25 例 Breslow 指数≥1mm 的黑色素瘤和 18 例经典复合型 Spitz 痣，研究了它们的组织病理学、免疫组织化学和分子遗传学特征。此外，还收集了 5 年的临床随访数据。我们发现 Spitz 痣和黑色素瘤在以下特征方面存在统计学显著差异：pagetoid 扩散、异型性、成熟、弹性组织变性、Kamino 小体、p16 表达和 HMB45 的染色模式。BRAF 在 7/21 例黑色素瘤和 1/14 例 Spitz 痣中呈阳性。荧光原位杂交在 37 例中的 36 例中证实了组织病理学诊断。我们的研究可以重现用于区分 Spitz 痣和黑色素瘤的既定临床、组织病理学和免疫组织化学标准。特别是，p16、BRAF 分析和荧光原位杂交的表达被证明是有助于提高我们研究中 Spitz 痣和黑色素瘤区分的有用工具。然而，到目前为止，还没有可靠的组织病理学和免疫组织化学参数可以绝对确定地区分 Spitz 痣和黑色素瘤。
