Abstract
A 13-year-old girl presented with asymmetric breasts 18 months earlier. She visited a neighboring clinic and was referred to our hospital. A firm, elastic, well-defined tumor measuring 9 cm was found on palpation. On ultrasonography, the tumor was found to occupy nearly the entire left breast and compress the normal breast tissue laterally. We suspected juvenile fibroadenoma based on the clinical findings and core needle biopsy pathology. The tumor was resected using an inframammary incision under her left nipple without injuring the normal breast. Juvenile fibroadenomas usually enlarge rapidly in adolescent breasts. It is important to distinguish juvenile fibroadenoma from a phyllodes tumor. The postoperative pathological examination revealed juvenile fibroadenoma. She has had no recurrence 2 years postoperatively. She has no obvious deformity and her left breast is symmetric with her right breast. It is important to preserve a functional, cosmetically acceptable breast because juvenile fibroadenoma is a common benign tumor among young adolescents.
