[Nonpalpable testicular masses incidentally discovered by ultrasound]

To determine the diagnosis and management of impalpable testicular masses detected sonographically.

We analyzed retrospectively the sonographic findings and pathologic results of such cases and reviewed related literature.

In over 600 patients receiving scrotal ultrasound, 14 aged on average 42.4 years (14 to 71 years) had 16 impalpable testicular masses, with a diameter of 5 to 30 mm (mean 12.1 mm). All masses were predominantly hypoechoic except for one appeared hyperechoic and calcified. Pathological examination showed 2 seminomas, 2 lymphomas, 2 testicular tuberculoses and cysts respectively. The other six were embryonal cell carcinoma, metastatic adenocarcinoma, testicular fibrosis, partial infarction, testis abscess, and hematoma. Malignant lesions accounted for 42.86% (6/14). In 13 of 14 patients, the affected testis was resected, while in 1 the testis spared for frozen sectioning revealed a benign cystic lesion.

Ultrasound findings can not differentiate malignant from benign in the impalpable lesions, and clinical history should be considered. All patients with indefinite diagnosis should undergo inguinal exploration and the testis can be spared if intraoperative frozen section diagnosis is negative. Ultrasound follow-up should be used only if there is a strong evidence of infection or trauma.