Histologic effects of testicular sperm extraction on the testicle in men with nonobstructive azoospermia

Testicular sperm extraction (TESE) is a therapeutic technique that has revolutionized the treatment of severe male infertility presenting as nonobstructive azoospermia. However, the procedure is not without side effects, involving at least a transient effect on spermatogenesis. The purpose of this study was to demonstrate the histologic effects of TESE on the testicle.

Testicular biopsy specimens were analyzed from 7 patients with nonobstructive azoospermia who each underwent two consecutive TESE procedures. We evaluated two biopsies at the same site on the testicle so that we could examine the histologic effects of the first TESE procedure with the second biopsy specimen. First, a quantitative evaluation of seminiferous tubular volume was performed with a 121-point grid over multiple fields of the testicular specimen slides. The second step of the analysis involved a comparison of the number of germ cells per tubule in each set of specimens. Both Student's t test and Wilcoxon matched pairs tests were used for analysis.

In the first set of TESE specimens, tubules comprised 33,158 of 63,525 grid points, or 52.2% of the specimen area. This decreased to 28,637 points, or 45.1%, in the second set of specimens. This decrease in seminiferous tubular volume and corresponding increase in interstitial tissue was statistically significant (P <0.00042). Our data also showed a 5.5% decrease in the number of germ cells per 91 tubules in each data set (from 3222 to 2887, P = 0.25), which suggests a trend toward a lower number of germ cells per tubule.

These findings support our clinical observation that TESE causes a decrease in seminiferous tubular volume within the testicular parenchyma adjacent to the biopsy site. This reflects a potentially adverse local effect of TESE on the testis that may have important clinical consequences for men with nonobstructive azoospermia.