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Updated: Jan 16, 2026

Spatial and Temporal Control of Murine Melanoma Initiation from Mutant Melanocyte Stem Cells
Published on: June 7, 2019
[The Spitz nevus is not a melanoma in childhood]
Mario Teufer1,2,3, Reinhard Dummer1,2
1Klinik für Dermatologie, Kantonsspital Aarau, Aarau.
Introduction:
The classic Spitz nevus is a benign, biologically stable melanocytic lesion in children and should not be equated with melanoma or its precursors. In contrast, Spitz tumors as a group represent a heterogeneous spectrum of melanocytic neoplasms, ranging from benign nevi to intermediate lesions with uncertain biological behavior and, rarely, malignant Spitz melanomas. Accurate classification relies on an integrative assessment of clinical, histological, and immunohistochemical features, complemented by molecular analyses in selected cases. Age-related risk stratification, growth behavior, architectural symmetry, and markers of maturation and proliferation are key determinants. The primary objective is not semantic categorization but rather a precise estimation of biological potential. This diagnostic approach helps to avoid overtreatment of stable lesions while enabling early detection of rare progressive cases. A structured, age-appropriate, and interdisciplinary diagnostic strategy is essential for informed and responsible clinical decision-making.
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