Needle Aspiration Biopsy of Seminiferous Tubules (NABST) as a Diagnostic Method in Korea.

To evaluate the diagnostic efficacy of needle aspiration biopsy of seminiferous tubules (NABST) and to represent the redistributed diagnostic results corresponding to testicular volumes and follicle-stimulating hormone (FSH) levels. In this retrospective study, we investigated 65 infertile men with either azoospermia or oligoasthenoteratozoospermia. Following NABST, specimens were stained with hematoxylin and eosin and classified into five histological types. With pre-procedure FSH levels and testicular volumes, we evaluated the probabilities of detecting sperms within biopsy specimens. NABST led to the classification of normal spermatogenesis in 31 cases (47.7%), hypospermatogenesis in 23 cases (35.4%), maturation arrest in 4 cases (6.2%), and Sertoli cell only syndrome in 4 cases (6.2%). The success rate of reaching a histological diagnosis using NABST was 95.4% (62 out of 65 cases). Fourteen patients (21.5%) had a testicular volume <15 cc; of these, 8 patients (57.1%) had normal spermatogenesis, 2 patients (14.3%) had hypospermatogenesis, 2 patients (14.3%) had maturation arrest and 2 patients (14.3%) had Sertoli cell-only syndrome (SCO). Twelve patients (18.5%) had an FSH level ≥10 IU; of these, 6 (50%) had normal spermatogenesis, 2 patients (16.7%) had maturation arrest and 4 patients (33.3%) had SCO. Cases with an FSH level <10 IU were positively associated with a probability of detecting sperm using NABST (p<0.001). NABST is a reliable tool for the histological diagnosis of azoospermic and oligoasthenoteratozoospermic patients. The diagnostic success rate was high and associated with pathological accuracy. NABST is a convenient procedure with few complications.