Management of contralateral testicular intraepithelial neoplasia in patients with testicular germ-cell tumor.

Contralateral biopsies from 1810 consecutive patients with testicular germ-cell tumor were examined immunohistologically by staining for placental alkaline phosphatase. Contralateral testicular intraepithelial neoplasia (TIN; carcinoma in situ) was found in 89 patients (4.9%; 95% confidence interval, 3.9%-5.9%). Testicular atrophy was present in 45.9% of patients with TIN and in 13.1% of those without TIN (P < 0.01). There was a history of cryptorchidism in 16.2% of patients with TIN versus only 8.5% of those without TIN (P < 0.05). Patients with contralateral TIN presented at an earlier age (30.8 versus 33.3 years). In all, 23 patients with contralateral TIN had no specific risk marker. In 14 patients with contralateral TIN who had received local radiotherapy of 18-20 Gy to the testis, rebiopsy revealed the disappearance of TIN in all cases. Serum testosterone levels were within or above the normal range in 7 of 13 patients examined after local radiotherapy. Of 9 patients with contralateral TIN who had received chemotherapy, 2 were shown to have persistent TIN at rebiopsy. We conclude that all patients with testicular germ-cell tumor should be offered a contralateral biopsy. Local radiotherapy of the testis is the treatment of choice in patients with contralateral TIN.