RESUMO
BACKGROUND: In newborns and infants, ovarian lesions can be detected during ultrasound examination before or after birth. Malignant ovarian lesions account for <1% of malignancies in newborns. However, in case of doubt about the nature of the lesion, surgery with tissue collection for histopathologic evaluation should be considered with the absolute condition of fertility preservation. OBSERVATIONS: The aim of this publication was to describe a case report of a 3-day-old infant who presented an ovarian lesion on postnatal ultrasound, with features suggesting a malignant nature of the ovary. In the described case, laparoscopy and mini-laparotomy were performed, torsion was excluded. The ovary was preserved, and histopathologic examination excluded the malignant nature of the lesion. CONCLUSION: A detailed analysis of the clinical status, laboratory tests, and imaging studies is necessary before making a final decision on further therapeutic, especially surgical management of a newborn with an ovarian lesion.