停留精巣の未来を探る : 造精機能獲得のための未来の治療

Abstract

Orchiopexy is one of the most frequently used surgical procedures for cryptorchidism and has been shown to have a beneficial effect on fertility. However, orchiopexy, especially for bilateral cryptorchidism, does not always guarantee subsequent fertility and paternity. Compared with a control group, paternity was significantly compromised in men with previous bilateral, but not unilateral cryptorchidism. Recent techniques of assisted reproductive technology, especially testicular sperm extraction with intracytoplasmic sperm injection (TESE-ICSI), have brought revolutionary changes in clinical therapy for infertiliy. If spermatozoa exists in testis of infertile men, logically there is a possibility of paternity. However, our study demonstrated that about 20% of pubertal boys who had had orchiopexy, were predicted to have lost their future paternity potential even if TESE-ICSI were conducted, because they were predicted to have no spermatozoa in the testis. To prevent or reverse the damage of spermatogenesis at prepuberty or puberty, we should not take a wait-and-see attitude but should consider a countermeasure for the pubertal boys who had had bilateral orchiopexy in childhood, especially when the serum follicle stimulating hormone level is elevated and testicular volume is lowered, before paternity is lost. In this review, we discuss the potential approaches including epidermal growth facter therapy, gene therapy and stem-cell therapy for cryptorchid patients in the future.