Synchronous Bilateral Primary Testicular Tumors With Discordant Histopathology.

Concomitant presentation of histologically distinct bilateral testicular tumors is exceedingly rare. Here we report the case of a 20-year-old male who presented with a left testicular mass. He was found to have bilateral testicular masses on ultrasound and underwent bilateral orchiectomy. Left testicular pathology revealed a mixed germ cell tumor consisting of teratoma, seminoma, and germ cell neoplasia in situ; right testicular pathology revealed two foci of pure seminomas. He is currently on active surveillance and remains in remission at 18-month follow-up. Our case demonstrates the rare occurrence of bilateral primary synchronous testicular tumors with different histopathology in each testis. Despite the rarity of this condition, its treatment is based on standard management of unilateral testicular carcinoma, with the added element of prioritization of one tumor over the other. It is important for clinicians to tailor management for bilateral testicular germ cell tumors according to the most aggressive component.