Natural history and long-term testicular growth of acquired undescended testis after spontaneous descent or pubertal orchidopexy.

OBJECTIVE

To assess prospectively the natural history and long-term testicular growth of acquired undescended testis (UDT) after spontaneous descent or pubertal orchidopexy in case of nondescent.

PATIENTS AND METHODS

From 1996 until 2008, 391 boys with 464 acquired UDT were included in the study. In accordance with Dutch consensus on non-scrotal testes, spontaneous descent at puberty was awaited; if this did not take place, orchidopexy was performed at puberty. Acquired UDT was defined as a testis previously residing in the scrotum that can no longer be manipulated into a stable scrotal (high scrotal) or nonscrotal (inguinal, impalpable) position. After referral, testis position, testis volume and puberty stage were monitored annually until adolescence. Testis volume was assessed using an orchidometer and compared with the Dutch standard. All investigations were carried out by the same physician (W.H.). Of these boys, 84 (mean age 12.9 years, range 6.4-21.3) were also clinically assessed by a second physician (J.G.), unaware of the results of the first examination. In addition, these boys were assessed with testicular ultrasonography, carried out by both physicians.

RESULTS

Currently the mean (range) follow-up is 4.7 (0.1-12.0) years, and 253 acquired UDT have reached the scrotum. In 196 of these 253 cases (77.5%), there was spontaneous descent at puberty (mean age at descent 12.9 years, range 9.8-16.9); in the other 57 cases (22.5%), pubertal orchidopexy was required due to nondescent; five cases required orchidectomy. Of the 494 testis volume measurements after spontaneous descent, 458 (92.7%) were at ≥10th centile for age, of which 311 (63.0%) were ≥50th centile, and 107 (21.7%) ≥90th centile. After pubertal orchidopexy for nondescent, of the 85 measurements, 79 (92.9%) were at ≥10th centile, 53 (62.4%) ≥50th centile and 12 (14.1%) ≥90th centile. In unilateral cases, after spontaneous descent 174 of the 294 (59.2%) retained testes were found to be smaller than their counterpart and 90 of 294 (30.6%) were equal in size. After pubertal orchidopexy in unilateral cases, 40 of the 51 (78.4%) testes were smaller, and nine (17.6%) were equal in size. There was a strong correlation between both investigators for the measurement of testicular volume by orchidometer, and for the main investigator (W.H.) between his measurements by ultrasonography and the Prader orchidometer.

CONCLUSION

Acquired UDT has a 77.5% tendency of spontaneous descent at puberty. In nearly all cases, after spontaneous descent as well as after pubertal orchidopexy, long-term testicular growth is within the normal range.