UROLOGICAL SURVEY   ( Download pdf )

 

INVESTIGATIVE UROLOGY

Relationship between adult dark spermatogonia and secretory capacity of Leydig cells in cryptorchidism
Zivkovic D, Bica DT, Hadziselimovic F
Institute for Child and Youth Health Care, Paediatric Urology, Novi Sad, Serbia and Montenegro
BJU Int. 2007; 100: 1147-9

  • Objective: To examine whether hormonal therapy before orchidopexy affects the histology of the testis and to assess the responsiveness of the Leydig cells, as it has been shown that although basal plasma testosterone levels are within the ‘normal’ range in cryptorchid boys there is an insufficient increase of testosterone after a human chorionic gonadotrophin (hCG) stimulation in approximately 30% of cryptorchid boys.
  • Patients and Methods: In all, 55 boys (aged 1-7 years) with a unilateral undescended testis were included in the study and divided into two groups. Group I (32 boys) received hormonal therapy before orchidopexy; 17 boys received a long-acting LHRH analogue (buserelin) administered as a nasal spray in doses of 20 microg/day for 28 days, followed by 1500 IU hCG intramuscularly (i.m.) once a week for 3 weeks, and the remaining 15 received 1500 IU hCG i.m. once a week for 3 weeks. Group II (33 boys) had orchidopexy alone. During orchidopexy biopsies were taken from the undescended and contralateral descended testes of the boys in both groups for histological analyses. Variations in the number of adult dark (Ad) spermatogonia per tubule (Ad/T) were assessed and testosterone levels were measured during the course of the hormonal therapy (before treatment, 14 days after initiation of buserelin administration, 24 h after each hCG injection, and 3 months after cessation of therapy).
  • Results: In group I, 17 boys (53%) had a ‘normal’ Ad/T after hormonal treatment vs only six (18%) in group II after orchidopexy alone (P = 0.019). In the hormonally treated boys (group I) we compared the testosterone values 24 h after the second injection of hCG (when the response was most pronounced). Those with a normal Ad/T had a mean (sd) testosterone level of 199.5 (97.6) ng/dL vs 99.6 (85) ng/dL in those with an inadequate Ad/T response to hormonal therapy (P < 0.003).
  • Conclusion: We have confirmed that there are two subgroups of cryptorchid boys. Patients with a sufficient Leydig cell secretory capacity will have normal testicular histology and Ad spermatogonia count after hormonal treatment. While those with a suboptimal Leydig cell capacity will have a low Ad spermatogonia count and consequently poor prognosis for future fertility, despite successful surgery. As to whether different types and durations of the hormonal therapy in patients with impaired Leydig cell response could lead to improved testicular histology and consequently improved prognosis for future fertility, remains to be answered.

  • Editorial Comment
    This paper presents new important insights on the understanding of cryptorchidism and its treatment and I will highlight some important points.
    The authors demonstrated for the first time, that the transformation of gonocytes into Ad spermatogonia is a testosterone-dependent process. If an adequate increase in plasma testosterone follows hormonal stimulation, normal germ-cell maturation occurs. Patients that have an insufficient Leydig cell response to hormonal stimulation, resulting in an inadequate testosterone increase, will have poor testicular histology and a low Ad spermatogonia count.
    Interesting, the authors concluded that appears to be two subgroups of cryptorchid boys; those with a sufficient Leydig cell secretory capacity and those with a suboptimal Leydig cell secretory capacity.

Dr. Francisco J.B. Sampaio
Full-Professor and Chair, Urogenital Research Unit
State University of Rio de Janeiro
Rio de Janeiro, RJ, Brazil