Cutaneous Spitz Melanocytoma

**Semantic type:** Neoplastic Process

**Definition:** A junctional or compound cutaneous melanocytic neoplasm not fulfilling the histopathologic criteria of melanoma but with one of the following features: asymmetry, predominance of single melanocytes over nests in lesions 4 mm or larger, ulceration, large dermal sheets of melanocytes, lack of maturation in dermis, deep dermal mitotic figures, extensive involvement of subcutis, and nuclear pleomorphism. (Mod Pathol 2006;19: S21)

**Synonyms:** - AST - STUMP - Skin Atypical Spitz Nevus - Skin Atypical Spitz Tumor - Skin Atypical Spitz Tumor of Uncertain Malignant Potential - Skin Melanocytic Tumor of Unknown Malignant Potential - Skin Pagetoid Spitz Nevus - Skin Spitz Melanocytoma - Skin Spitz Tumor with One or More Atypical Features - Skin Spitzoid Tumor of Uncertain Malignant Potential