AUTHOR=Di Ruscio Valentina , Del Baldo Giada , De Pasquale Maria Debora , De Vito Rita , Miele Evelina , Colafati Giovanna Stefania , Deodati Annalisa , De Ioris Maria Antonietta , Tornesello Assunta , Milano Giuseppe Maria , Mastronuzzi Angela TITLE=Ectopic ACTH Secretion in a Child With Metastatic Ewing's Sarcoma: A Case Report JOURNAL=Frontiers in Oncology VOLUME=Volume 10 - 2020 YEAR=2020 URL=https://www.frontiersin.org/journals/oncology/articles/10.3389/fonc.2020.00574 DOI=10.3389/fonc.2020.00574 ISSN=2234-943X ABSTRACT=Ectopic ACTH syndrome is rare in pediatric age. Sarcomas causing Ectopic ACTH Syndrome (EAS) are even uncommon. At the current time, only three cases of EAS caused by Ewing’ sarcoma are reported. We describe a 10-year-old boy presenting with Cushing's syndrome caused by ectopic ACTH production by a metastatic Ewing's sarcoma of the right ischio-pubic and ileo-pubic branches. Rapid appearance of cushingoid symptoms, with rapid weight gain, acne, hirsutism, and hypercortisolism with high levels of ACTH and non-suppression high dose dexamethasone test were diagnostic for ectopic ACTH production as paraneoplastic Cushing's Syndrome. We underline the possibility of EAS caused by an ACTH-secreting tumor, including soft tissue sarcomas.