Imaging of bilateral synchronous testicular tumors of different histologic types and implications for surgical management

Bilateral testicular tumors are rare, accounting for only 0.5% to 5% of all testicular cancers. Most are metachronous, discovered in the contralateral testis during follow-up; less frequently (≈35%), they are synchronous lesions.1 Although the same histologic type is usually supposed for bilateral tumors, lesions with different histologic types are not unusual. Large studies on the incidence and clinical and histologic characteristics of bilateral germ cell tumors report that the number of patients with lesions of different histologic types varies widely, from 25% up to 70%.1–5 Different histologic types in patients with bilateral, synchronous lesions have been reported to occur in 31.6% of cases.1 The widespread use of imaging for any scrotal problem has shown that not all focal lesions in the testis are malignancies, especially when small.6 An effort to characterize them preoperatively is then worthwhile. When the lesion does not have malignant characteristics, a conservative surgical approach is suggested, and decisions are made after confirmation of its nature by a frozen section pathologic examination.6 There are only a few case reports of the imaging appearances of synchronous bilateral lesions of different histologic types.7–9 The purpose of this article is 2-fold: (1) to describe the imaging features encountered in 4 patients with bilateral synchronous testicular tumors that proved to be of different histologic types at pathologic examination; and (2) to discuss the role of imaging in guiding the surgical approach to patients with those lesions