Systematic fine-needle aspiration of the testis: Correlation to biopsy and results of organ “mapping” for mature sperm in azoospermic men

Abstract

Objectives This study compares fine-needle aspiration (FNA) and testis biopsy for the ability to detect mature sperm in the testes of azoospermic men. In addition, we introduce the concept of testis “mapping” with FNA and apply it to detect sperm in men with severe testis failure. Methods Sixteen patients were evaluated for azoospermia in a university-based infertility clinic. All men had testis biopsies and FNAs from matched testicular sites to assess for the presence of spermatozoa. Adequacy criteria for FNA specimens were strictly defined, and correlative analysis of the two techniques was performed. In addition, a subset of 12 men with nonobstructive azoospermia (NOA) had systematic FNA mapping (more than four FNA sites per testis) to detect mature sperm for potential clinical use. Results Adequate FNA specimens were obtained in 115 (91.3%) of 126 FNA attempts. Of 34 paired biopsy FNA sites, FNA was seen to be more sensitive than, and equally specific as, testis biopsy for sperm detection. When compared with the biopsy touch imprint, FNA was equally as sensitive and specific. Among men with NOA who underwent FNA mapping, 4 (33%) of 12 had localized “patches” of sperm detected in areas distant from sperm-negative biopsy sites. In 1 case, a pregnancy was achieved with later biopsy and sperm extraction “directed” by previous FNA. Conclusions For sperm detection, testis FNA provides equivalent or better information than a testis biopsy. FNA can localize areas of sperm production within the testis and accurately guide sperm extraction procedures in men with NOA.