Spitzoid lesions represent a dermoscopic and anatomopathological challenge. While the spitzoid phenotype is easily recognizable, the differential diagnosis between Spitz nevus, atypical Spitz tumor, and spitzoid melanoma is difficult, requiring the integration of clinical, dermoscopic, histological, and molecular biological criteria.
Three main dermoscopic patterns define the Spitz nevus without asserting its benignity: the starburst pattern, the globular pattern and the vascular pattern. Symmetrical distribution of colors and structures, nodularity, ulcerations, shiny white streak, and age (>/≤ 12 years) must also be taken into account before deciding whether to reassure these patients, monitor the lesions or excise them. Based on these criteria, the International Society of Dermoscopy proposed a management algorithm (Figure 4).
Histologically, the Spitz nevus is composed of multiple epithelioid cells with nucleated nucleoli packed within hyperplastic epidermis. The following criteria must be integrated to enable the histological differential diagnosis between typical or atypical spitzoid tumors, including symmetrical distribution of structures, patient’s age, lesion diameter, infiltration of subcutaneous tissue, ulceration, mitotic index, and presence of genetic alterations.
Key Words
Spitzoid lesions, Spitz nevus, atypical Spitz tumor, spitzoid melanoma