Combination of giant fibroadenoma and galactocele: two rare benign breast lesions in a 27-year-old mother presenting with a long-standing breast mass: a case report

Introduction and Importance: A galactocele is a rare, benign cystic breast lesion caused by obstruction of the lactiferous ducts, leading to milk accumulation. Fibroadenoma is the most common benign breast tumor; however, giant fibroadenomas account for only 0.5% of cases. While isolated giant galactoceles and giant fibroadenomas have been reported as causes of long-standing breast masses, their simultaneous occurrence within a single mass has not been previously described. This case highlights the rare coexistence of these lesions and underscores the need for a multidisciplinary approach involving surgeons, pathologists, radiologists, and reconstructive specialists. Clinical Presentation: A 27-year-old para I woman presented with a left breast swelling of three years’ duration. It began as a small, palpable lump that gradually increased in size. She did not seek medical attention during the first 2 years. Over the past year, the mass enlarged rapidly, causing pain and pressure that disrupted her sleep and daily activities. Physical examination revealed a 20 × 15 cm mass in the left breast. Breast ultrasonography and fine-needle aspiration cytology were performed, and the patient opted for mastectomy. Histopathologic examination confirmed the diagnosis. Clinical Discussion: The coexistence of a giant fibroadenoma and a galactocele within a single breast mass is extremely rare. Radiologic imaging can support the diagnosis; however, definitive diagnosis often requires histopathologic evaluation. Conclusion: Although both giant fibroadenomas and galactoceles are benign lesions, they can mimic malignant breast tumors. Careful evaluation is necessary to distinguish them from malignancy and to ensure the early detection or exclusion of breast cancer.