Neurofibromatosis: a cause of prepubertal gynecomastia.

BACKGROUND

Atypical presentations of gynecomastia not associated with obesity are often underappreciated. Unilateral manifestation, prepubertal onset, and a history of associated disorders may contribute to a unique clinical presentation for which the diagnosis and management may remain uncertain. This report reviews neurofibromatosis as a cause for atypical presentation of gynecomastia in prepubertal boys to help establish guidelines for diagnosis and management.

METHODS

Six nonobese male patients (body mass index <or=20) had an onset of gynecomastia at younger than 9 years and were referred for evaluation between June of 1994 and December of 2006.

RESULTS

The median age of onset of breast enlargement was 7(1/2) years (range, 4 to 8 years). Three had bilateral involvement, four had localized involvement of the nipple-areola complex, and two had diffusely involved breast tissue. Five of the six patients were African American (compared with 20 percent for classic gynecomastia). Median postoperative follow-up was 7 years, and all were followed beyond puberty. No recurrences were seen, although one patient developed a metachronous lesion in the contralateral breast. No patient had an abnormal endocrine metabolic workup.

CONCLUSIONS

Atypical gynecomastia may present in the prepubertal boy and appears more prevalent in African Americans. For neurofibromatosis, it is more likely unilateral, can be localized to the nipple-areola complex, or entails diffuse breast involvement. An endocrine workup appears to be noncontributory.