Testicular-sparing surgery may avoid definitive testosterone supplementation and preserve fertility in selected cases of men presenting with bilateral testicular tumours or in case of monorchidia. Testicular-sparing surgery may enable the conservation of both endocrine function and spermatogenesis in selected young men in order to preserve natural fatherhood, avoid definitive androgen replacement therapy and probably improve quality of life by reducing psychosexual consequences of anorchia. The tumorectomy must be followed by an external irradiation of the remaining testicle to eradicate testicular intratubular neoplasia revealed in 82 % of cases after per-surgery biopsy. This approach concerns some rare indications. Dose level and technical consideration are still debated.