Are Breast Masses in Teenagers Always Benign? Undifferentiated Mesenchymal Sarcoma in a 14-Year-Old Girl.

BACKGROUND: This article is concerned with the evaluation of an adolescent breast mass using imaging methods. CASE REPORT: A 14-year-old girl presented with progressive asymmetric enlargement of the left breast. She had felt a breast lump about 4 months earlier, and over the last 2 months it had been growing progressively. Tumor markers, including AFP, CEA, CA15-3, and CA125, were all normal. Ultrasonography showed a hypoechoichyperechoic, solid mass. Magnetic resonance imaging of the breast revealed a well marginated mass with hypointensity on T1-weighted images and mild hyperintensity on T2-weighted images, which showed mild contrast uptake. Biopsy revealed an undifferentiated malignant mesenchymal sarcoma. The patient underwent mastectomy with axillary lymph node sampling. After the operation, she received 3 cycles of chemotherapy and radiotherapy. CONCLUSION: Due to the rarity of breast sarcoma and inadequate imaging methods to establish an exact diagnosis, radiologists and clinicians may misdiagnose and merely follow these tumors. As in our case, the histology of the patient may be the leading factor in the management of these tumors. Even in very young patients, progressively growing breast masses should alert the clinician to check for malignancy verified by biopsy.