Introduction: Fibroadenoma is the most common benign lesion of breast in young women, characterized by an aberrant proliferation of both epithelial and mesenchymal elements. It is termed giant fibroadenoma when it is larger than 5 cm or weighs more than 500 g with an incidence of 0.5-2% of all fibroadenomas.Presentation of case: In this report, we discuss a case of a 13-year-old Pakistani girl who presented with a giant juvenile fibroadenoma in left breast and was treated by a subareolar lump excision through a periareolar incision with excellent cosmetic outcome. To the best of our literature search, this is the first case of giant juvenile fibroadenoma in an adolescent being reported from Pakistan.Discussion: Surgical management of giant juvenile fibroadenoma in immature breast is challenging as it may either result in asymmetric defect or damage to developing breast tissue resulting in long term poor outcomes. Surgical decision should be carefully undertaken and reported for future reference in such cases.Conclusion: The diagnosis and management of giant juvenile fibroadenoma can be challenging because these tumors clinically and histologically mimic phyllodes tumor due to their rapid growth and large size. Excision through a periareolar approach for fibroadenomas located in subareolar region provides good cosmetic results in these patients with minimal scar visibility
