Differential Diagnosis for a 15-year-old Girl with a Self-Palpated Breast Mass
- Single most likely diagnosis
- Fibroadenoma: This is the most common benign breast tumor in adolescents and young women. The description of the mass as firm, smooth, and mobile is consistent with a fibroadenoma. The patient's age and the fact that the mass is mildly tender also support this diagnosis.
- Other Likely diagnoses
- Breast cyst: Although less common in adolescents, breast cysts can occur and may present as a palpable mass. The mild tenderness could be related to a cyst, especially if it is fluctuant.
- Phyllodes tumor: These are rare but can occur in adolescents. They are usually firm and mobile, similar to fibroadenomas, but can grow larger.
- Normal breast tissue or fibrocystic changes: As the patient is in her early reproductive years, her breasts may be more dense and lumpy due to hormonal fluctuations, which could be mistaken for a mass.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed)
- Breast cancer: Although extremely rare in adolescents, breast cancer can occur, especially with a family history of breast cancer, as in this patient's case. It is crucial to not overlook this possibility, despite its low likelihood.
- Sarcoma (e.g., angiosarcoma, liposarcoma): These are very rare tumors that can occur in the breast and have a poor prognosis if not diagnosed early.
- Rare diagnoses
- Granulomatous mastitis: An inflammatory condition that can mimic a breast tumor. It's rare and more commonly seen in older women but should be considered if other diagnoses are ruled out.
- Pseudoangiomatous stromal hyperplasia (PASH): A rare benign condition that can form masses in the breast. It's more common in young women but is not as frequent as fibroadenoma.
- Hamartoma: A benign tumor-like growth that can occur in the breast, composed of normal breast tissue elements. It's rare and usually presents as a firm, mobile mass.