Fine-needle aspiration of the testis in azoospermic men: the value of measuring serum follicle stimulating hormone and testicular size.

Testicular fine-needle aspiration biopsy (FNAB) is used as a primary tool in assessing azoospermic infertile men in our institution. If the FNA is negative for sperm, a subsequent testicular biopsy specimen and wet preparation are obtained with possible immediate fertilization. To our knowledge, the value of these techniques in the context of testicular size and serum levels of follicle stimulating hormone (FSH) has not been explored. We reviewed 453 FNA biopsies of the testis performed for the identification of sperm in infertile azoospermic males between 1999 and 2000. We identified cases that had all three procedures (FNA, wet preparation and biopsy) performed. These were the patients that were compared for testicular size using Seager orchiometry and serum levels of FSH. Of the 453 FNAs reviewed, 128 (21%) had all three procedures performed. Seventy-two cases (56%) were negative in all three tests, 26 (20%) cases were positive in all tests, and 30 cases (23%) had different results. These 30 cases were excluded. The testicular size in the negative group ranged from 4 to 16 ml (median, 10 ml) and the positive group had testicular sizes ranging from 10 to 25 ml (median, 15 ml; P = 0.0001). The negative group had serum FSH levels ranging from 3 to 52 IU/l (median, 19 IU/l) whereas the positive group had serum levels ranging from 3 to 26 IU/l (median, 10 IU/l; P = 0.0001). Our findings suggest that in infertile azoospermic men, a testicular size of <10 ml combined with a serum FSH level of >19 IU/l, the chances of retrieving sperm are minimal using all three diagnostic modalities. The use of this cutoff point would lead to a 30-50% reduction in the number of procedures performed. This reduction would have a significant impact on the management of these patients with a significant decrease in cost, logistics, and patient anxiety.