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Contralateral testicular biopsy in testis cancer: current concepts and controversies

Of all patients with unilateral testis cancer, ≈5% harbour testicular intraepithelial neoplasia (TIN) in their contralateral testicle that will progress into an invasive germ cell tumour over time. The accurate diagnosis of TIN by a random two‐site surgical testis biopsy and effective therapy by local radiation has led to the concept of a contralateral screening biopsy in all patients with testis cancer. However, screening and preventive treatment are only indicated if the therapeutic outcome of the screened population is improved, and the physiological function of the affected organ is not impaired. Based on a critical review of previous reports, some drawbacks of this policy have to be considered and question the routine indication for contralateral testis biopsy: (i) all TIN‐negative patients still have to undergo meticulous follow‐up for metachronous testis cancer due to a false negative biopsy rate of 0.5–1.0%; (ii) local radiation of TIN results in irreversible infertility due to eradication of spermatogenesis; (iii) local radiation of TIN results in an impairment of endocrine Leydig cell function in 25% of the patients; (iv) therapeutic outcome and prognosis will not be improved in irradiated patients as compared to patients on surveillance; (v) local tumour resection for the management of metachronous testicular cancer represents an effective and viable option. Current reports do not support the strategy of contralateral testis biopsy in all patients with unilateral testicular germ cell tumours. According to the recommendations of the European Germ Cell Cancer Consensus Group, a testis biopsy might be offered to high‐risk patients for contralateral TIN (testicular volume <12 mL, history of cryptorchidism, age <30 years).