This common benign neoplasm occurs most frequently in young women, usually within 20 years after puberty. It is somewhat more frequent and tends to occur at an earlier age in black women. Multiple tumors are found in 10-15% of patients.

The typical fibroadenoma is a round or ovoid, rubbery, discrete, relatively movable, nontender mass 1-5 cm in diameter. It is usually discovered accidentally. Clinical diagnosis in young patients is generally not difficult. In women over 30 years, fibrocystic condition of the breast and carcinoma of the breast must be considered. Cysts can be identified by aspiration or ultrasonography. Fibroadenoma does not normally occur after the menopause, but may occasionally develop after administration of hormones.

No treatment is usually necessary if the diagnosis can be made by needle biopsy or cytologic examination. Excision or vacuum-assisted core needle removal with pathologic examination of the specimen is performed if the diagnosis is uncertain. Cryoablation is being attempted as an alternative to excision. It is usually not possible to distinguish a large fibroadenoma from a phyllodes tumor on the basis of needle biopsy results.

Phyllodes tumor is a fibroadenoma-like tumor with cellular stroma that grows rapidly. It may reach a large size and if inadequately excised will recur locally. The lesion can be benign or malignant. If benign, phyllodes tumor is treated by local excision with a margin of surrounding breast tissue. The treatment of malignant phyllodes tumor is more controversial, but complete removal of the tumor with a rim of normal tissue avoids recurrence. Because these tumors may be large, simple mastectomy is sometimes necessary. Lymph node dissection is not performed, since the sarcomatous portion of the tumor metastasizes to the lungs and not the lymph nodes.

_{Barbosa ML et al: Cytogenetic findings in phyllodes tumor and fibroadenomas of the breast. Cancer Genet Cytogenet 2004;154:156. Pubmed: 15474152}

El-Wakeel H et al: Systematic review of fibroadenoma as a risk factor for breast cancer. Breast 2003;12:302. Pubmed: 14659144

Fine RE et al: Percutaneous removal of benign breast masses using a vacuum-assisted hand-held device with ultrasound guidance. Am J Surg 2002;184:332. Pubmed: 12383895

Kaufman CS et al: Cryoablation treatment of benign breast lesions with 12-month follow-up. Am J Surg 2004;188:340. Pubmed: 15474424