An atypical Spitz tumor with metastasis in an adolescent patient

Despite the large number of studies published in the dermatologic and anatomopathologic literature, there are still many doubts and controversies regarding the natural history and behavior of atypical Spitz tumors (ASTs) in children. We report the case of an AST that developed metastases 5 years after the first surgical excision. In 2012, a 12-year-old boy underwent surgical excision of a melanocytic lesion of the right forearm, which was histologically classified as an AST. After multidisciplinary evaluation, a wide local excision was performed, avoiding sentinel lymph node biopsy. During follow-up, metastatic disease was diagnosed in 2017, leading to a diagnosis of stage IV melanoma. Despite multimodal treatments, including therapies that were off-label at the time due to the patient's age, disease progression occurred and the patient died in 2021. The management of AST remains controversial, reflecting the clinicopathologic gray zone occupied by borderline spitzoid tumors, in which morphology alone may be inadequate to predict biological behavior.