Multiple hyperechoic testicular lesions are a common finding on ultrasound in Cowden disease and represent lipomatosis of the testis.

Cowden disease (CD) is a genetic disease associated with multiple hamartomas and malignant neoplasms. During investigations for possible subnormal fertility, a series of eight males with CD underwent ultrasound scanning of their testes. Our findings detail the seven adult patients that were found to have multiple and bilateral testicular lesions on ultrasound. These lesions in Cowden's patients represent a newly described testicular pathology - lipomatosis of the testis. Here we detail the radiological findings. Ultrasound findings showed multiple (estimated 40+) discreet lesions randomly scattered thoughout the parenchyma of each affected testis. The lesions themselves had heterogeneous echo texture, but all being hyperechoic and with a variable size from 1 mm to 6 mm. One patient underwent MR examination of the lesions in which a high T(1) signal was seen, but no useful characteristic features were identifiable.