Low attenuation nodal metastases in testicular carcinoma.

Abdominal and thoracic computed tomography examinations were abnormal in 23 of 57 patients (40.5%) with seminomatous and nonseminomatous testicular tumors. Lymph node metastases measuring less than 30 Hounsfield units (HU) occurred in 10 of these 23 patients (43.5%), five with seminoma, four with mixed germ cell tumors, and one patient with embryonal cell carcinoma. Biopsy material was obtained from low attenuation metastases in four patients. Three patients who had completed chemotherapy had evidence of extensive necrosis, but two of three had persistent tumor. In the fourth patient, a case of untreated mixed germ cell tumor, there were numerous small epithelial-lined cystic spaces. Biopsies from five patients with nodal masses measuring greater than 30 HU showed no necrosis or cystic change. There was no significant correlation between the attenuation characteristics of the metastases and clinical activity of the tumor.