Testicular malignant lymphoma; imaging and diagnosis.

The sonographic and magnetic resonance imaging findings of three cases of surgically proven malignant lymphoma of the testis were reviewed and their diagnostic implications were evaluated. In all three cases ultrasonography showed striated hypoechoic bands with paralleling hyperechoic lines radiating peripherally from the mediastinum testis. We believe they represented blood vessels. On T1-weighted MR images, the tumor showed homogenous hyperintensity in one case and homogenous isointensity in the other two. On T2-weighted images the tumor showed homogenous hypointensity in two cases and homogenous isointensity in one. After Gd-DTPA administration, the tumor showed homogenous enhancement in two cases and inhomogenous enhancement in one. In two cases there were enhancing striated bands in the tumor. Despite the diffuse infiltration by the tumor, the basic architecture of the testis, epididymis, and spermatic cord was preserved. When MRI and ultrasonography show an infiltrative disease preserving the basic architecture of the testis and ultrasonography presents hypoechoic bands radiating peripherally from the mediastinum testis, a diagnosis of malignant lymphoma should be considered.