Extraskeletal Ewing sarcoma (EES) is a rare tumor that affects men between 10-20 years old and represents 25% of Ewing sarcomas. We report a case due to the previous diagnosis of a fast-growing lipoma to highlight the importance of histopathological diagnosis. A 14-year-old boy presented 10x10 cm tumor in the right shoulder for a year with ultrasonography suggesting lipoma. The lesion was excised and EES was confirmed by immunohistochemical analysis. EES diagnosis in young people is challenging compared to subcutaneous tumors, and histopathology is essential. The rapid progression of the tumor and high metastatic rates highlight the significance of early treatment.

Keywords: Sarcoma, Ewing; Neuroectodermal tumors; Sarcoma

Piebaldism is a rare, autosomal dominant dyschromia characterized by circumscribed poliosis and triangular achromia in the frontal region in 90% of affected individuals, with no other systemic involvement. The incidence of dyschromia in this Dermatology Department, in a short space of time, and with plenty of images, motivated the presentation of this series of cases. We show two families with piebaldism, treated at the same Dermatology Department in 2021: the first family, with a mother and son presenting achromic macules on the trunk and poliosis in the frontal region since birth; the second family, with a grandmother, aunt, mother, and son showing the same characteristics described.

Keywords: Piebaldism; Pigmentation Disorders; Skin Diseases; Genetic