RESUMO
Congenital melanocytic nevi (CMN) are benign melanocytic proliferations that are usually present at birth. A somatic mosaicism for an NRAS point mutation is responsible for the several phenotypic abnormalities that may be associated with congenital nevi. We report the case of a 7-year-old boy with a proliferative nodule (PN) arising in a Giant CMN completely excised and with several visceral and intraspinal melanoma metastases with no evidence of primary cutaneous melanoma. The careful analysis of the clinical, morphologic, and molecular features allowed the distinction of between the benign PN (BPN) and the melanoma. The BPN showed a characteristic comparative genomic hybridization pattern with gains or losses of whole chromosomes, whereas the melanoma displayed gains or losses involving complex partial chromosomal copy number gains or losses. Leptomeningeal melanocytes are more susceptible to transformation by oncogenic NRAS than cutaneous melanocytes, and central nervous system melanomas are more common than cutaneous melanomas in the setting of CMN. Thus, it has been recommended to characterize the congenital disease in patients with 2 CMN at birth, independently of size and site, with a single magnetic resonance imaging screening younger than the age of 1 year.
Assuntos
GTP Fosfo-Hidrolases/genética , Melanoma/genética , Proteínas de Membrana/genética , Nevo Pigmentado/genética , Neoplasias Cutâneas/genética , Criança , Humanos , Masculino , Melanoma/patologia , Mutação , Metástase Neoplásica/genética , Metástase Neoplásica/patologia , Nevo Pigmentado/patologia , Neoplasias Cutâneas/patologia , Melanoma Maligno CutâneoRESUMO
Classically known as the "Great Imitator", the diagnosis of syphilis continues to be an enormous challenge. We describe a case of isolated oral lesions as the sole presentation of secondary syphilis and only clinical clue to previously undiagnosed human immunodeficiency virus infection. The current increase in new cases of syphilis is leading to reemergence of forgotten old scenarios, which physicians should bear in mind within the differential diagnosis of their daily practice.