Outcome of microdissection TESE compared with conventional TESE in non-obstructive azoospermia: a systematic review

Retrieval of spermatozoa is unfortunately still only successful in a subset of patients suffering from non-obstructive azoospermia (NOA) by conventional testicular sperm extraction (TESE). Microdissection TESE may have some theoretical benefits over conventional TESE, but uncertainty exists about its superiority. The objective of this systematic review was therefore to compare the efficacy and safety of microTESE with conventional TESE in men with NOA. The systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis statement. Literature was searched for studies comparing outcome of conventional TESE with microdissection TESE. Primary outcome was sperm retrieval rate (SRR). Secondary outcomes were clinical predictors of sperm retrieval as well as complication rate. Of 62 articles, a total of seven studies were included in the final analysis. Overall SRR was significantly higher in the microTESE group in comparison with conventional TESE in five of these studies. Overall sperm retrieval ranged from 16.7 to 45% in the conventional TESE vs. 42.9 to 63% in the microTESE group. A sub-analysis of the SRR according to testicular histology was available in four of the selected articles. MicroTESE in men with Sertoli cell only syndrome and hypospermatogenesis carried a small but significant more favourable outcome according to, respectively, two and one of the studies. Correlation of serum follicle stimulating hormone and testicular volume with positive outcome was variable. Fewer complications were observed on ultrasound examination after microTESE procedure. Clinical randomized studies comparing microTESE with conventional TESE in NOA are still lacking to date. Pseudo-randomized prospective data, however, show more favourable sperm retrieval in NOA for microTESE, especially in histological patterns of patchy spermatogenesis such as Sertoli cell only syndrome. However, in patients with uniform histological patterns such as maturation arrest outcome of microTESE seems less favourable.