Magnetic resonance imaging of pediatric liver tumors.

Liver tumors in children can be benign or malignant. Although several clinical factors are important in the evaluation of these lesions, MRI is particularly important for lesion characterization and tumor staging. In children, use of a hepatobiliary contrast agent is recommended to evaluate a known or suspected liver lesion. In this review, we discuss the most common benign and malignant pediatric liver tumors, including vascular tumors, mesenchymal hamartoma, focal nodular hyperplasia, hepatocellular adenoma, hepatoblastoma, hepatocellular carcinoma, fibrolamellar hepatocellular carcinoma, undifferentiated embryonal sarcoma and metastases, with emphasis on relevant clinical information and imaging appearance at MRI using hepatobiliary agents.

Nipple Adenoma: Correlation of Imaging Findings and Histopathology.

Nipple adenomas (NAs) are benign neoplasms composed of papillary hyperplasia of the epithelium of the major lactiferous ducts. Patients with NA may report bloody nipple discharge and clinically may resemble Paget disease, raising concern for malignancy. Mammographically, NAs are often occult. US can show a hypervascular circumscribed mass centered within the nipple with varying echogenicity. Diagnosis is usually made on punch biopsy or excision, but breast radiologists should be aware of this entity. Malignancy can be found elsewhere in the ipsilateral or contralateral breast, or very rarely may directly extend to involve an NA, but published experience with concurrent malignancies is small. We describe the radiologic-pathologic correlation of NAs.