ABSTRACT
INTRODUCTION AND IMPORTANCE: Breast pathology in adolescents is rare and predominantly benign, with abnormalities including congenital anomalies, infections, mastodynia, nipple discharge, and mostly benign breast masses. Fibroepithelial tumors, the most common type, form a heterogeneous group that includes benign, borderline, and malignant entities such as phyllodes tumors. Differentiation of these tumors, especially various types of fibroadenomas, requires histopathological examination due to their similar radiological appearances and lesion heterogeneity. Recognizing the nature of these lesions is crucial to avoid missing malignant forms with metastatic potential. Giant juvenile fibroadenoma is a quite rare benign fibroepithelial tumour, that cannot be differentiate from phyllodes tumors before anatomopathological examination. CASE REPORT: We report the case of a 14-year-old patient who presented with a rapidly enlarging mass in the left breast, and the diagnosis of giant juvenile adenofibroma was confirmed after surgical treatment. CLINICAL DISCUSSION: Giant juvenile fibroadenomas occurs in adolescent girl and constitutes 0.5 % - 4 % of all fibroadenomas cases. When it exceeds 5 cm, weighs more than 500 g, or occupies more than 4/5 of the breast, it is considered as giant. It is characterized by a rapid increase in size, causing distortion and compression of the breast. Breast ultrasound is the first imaging modality, showing a large, well-limited hypo or iso echoic mass. The main differential diagnosis should be made with phyllodes tumors. The diagnosis is considered based on clinical and radiological features but is confirmed only after surgical excision of the mass and histological study. CONCLUSION: The discovery of a breast mass in an adolescent should prompt further investigations to avoid overlooking a fibroepithelial tumour. The most probable diagnoses are giant juvenile fibroadenoma and phyllodes tumors.