Puberty stage and spontaneous descent of acquired undescended testis: implications for therapy?

We assessed spontaneous descent of acquired undescended testis (UDT) at puberty. 299 Boys (aged 1.2-16.5 years, mean 9.4) with 350 acquired-UDT were examined annually during a 12.6-year period (mean 3.1). An acquired-UDT was defined as a previously intrascrotal testis which can no longer be manipulated into a stable scrotal position. Each year, position of the testis and pubertal development according to Tanner's stages were assessed. Early puberty was defined as puberty stage G2 (testicular volume 4-9 mL), mid-puberty as puberty stages G3 (testicular volume 10 mL) and G4 (testicular volume 11-15 mL), and late puberty as puberty stage G5 (testicular volume >15 mL). Follow-up was completed if spontaneous descent had occurred, if mid-pubertal orchidopexy (ORP) had to be performed, if the boy was lost for follow-up, or if pre-pubertal ORP was performed in another hospital. In 139 boys with 164 acquired-UDT follow-up was meanwhile completed. Twelve boys with 14 UDT were lost for follow-up. In an additional 16 boys with 21 UDT, ORP was performed in another hospital. In 98 of the remaining 129 (76.0%) acquired-UDT spontaneous descent at puberty occurred. Mean follow-up was 2.5 years (range 0.2-8.5). In 70 of 98 testes (71.4%) descent occurred in early puberty, in 26 of 98 testes (26.5%) in mid-puberty, and in two testes in late puberty. In 31 of 129 testes (24.0%) ORP had to be performed at mid (30 cases) or late (one case) puberty. In this series, 98 of 129 acquired-UDT (76.0%) descended spontaneously at puberty, whereas in 31 of 129 (24.0%) pubertal ORP was performed. If ORP is postponed until puberty stage G3 (testicular volume of 10 mL) three of four acquired-UDT will descend spontaneously.