MRI in patients with axillary metastases of occult breast carcinoma.

In 4 women with adenocarcinoma metastasis in an axillary lymph node and no primary tumor found, we investigated whether Magnetic Resonance Imaging (MRI) of the breast could detect a clinically and mammographically occult breast tumor. MRI detected an enhancing lesion in 3 women and an enhancing double lesion in one patient. MRI directed ultrasound guided fine needle aspiration cytology confirmed the 5 breast carcinomas in the 4 women. In women with metastasis in an axillary lymph node consistent with breast cancer and without a primary tumor, MRI of the breast should added to clinical examination and mammography before defining it as an occult primary and planning therapy.