title: Prepubertal unilateral gynecomastia in the absence of endocrine abnormalities.
abstract: Gynecomastia is defined as the excessive development of breast tissue in males, which can occur as unilateral or bilateral. Although the overall prevalence of gynecomastia is 40%-65%, the prepubertal unilateral gynecomastia in the absence of endocrine abnormalities is unusual, with only a few case reports in literature. Idiopathic gynecomastia in prepuberty is benign but a diagnosis of exclusion. We here report two cases of healthy prepubertal boys aged 8.8 and 9.6 years old, respectively, presented with painful palpable mass in their unilateral breast. Breast tissue with glandular proliferation was confirmed on ultrasonography. Serum levels of estradiol, testosterone, and other laboratory findings were within normal range. They seem to have the prepubertal idiopathic gynecomastia but further follow-up to see their progression is needed.
authors.affiliation: Department of Pediatrics, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea.
authors.forename: Min
authors.initials: M
authors.lastname: Kang
authors.affiliation: Department of Pediatrics, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea.
authors.forename: Chan Jae
authors.initials: CJ
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Hallym University Kangdong Sacred Heart Hospital, Hallym University College of Medicine, Seoul, Korea.
authors.forename: Il Tae
authors.initials: IT
authors.lastname: Hwang
authors.affiliation: Department Diagnostic Radiology, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea.
authors.forename: Kwanseop
authors.initials: K
authors.lastname: Lee
authors.affiliation: Department of Pediatrics, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Korea.
authors.forename: Min Jae
authors.initials: MJ
authors.lastname: Kang
keywords: Child; Gynecomastia; Prepuberty