Deoxyribonucleic Acid Flow Cytometry in the Assessment of Spermatogenesis

Purpose

We compared deoxyribonucleic acid (DNA) flow cytometric analysis of testicular tissue to quantitative assessment of spermatogenesis.

Materials and Methods

We studied 35 infertile men with azoospermia or oligospermia. All patients underwent incisional testicular biopsies. DNA flow cytometric analysis was performed on each specimen to evaluate the ability of the method to quantify alterations in spermatogenesis. The results were compared to quantitative histological examination. At least 100 spermatic tubules were examined on each specimen and the number of spermatids per tubule was counted. All histological specimens were examined by the same pathologist.

Results

Of the 35 specimens analyzed with DNA flow cytometry 5 were normal, while the percentage of haploid cells (spermatids and spermatozoa) was decreased (hypospermatogenesis) in 14, complete maturation arrest was noted in 2 and almost complete absence of haploid cells was found in 14. Comparing the findings on histological examination with histograms, excellent correlation was noted in cases of the Sertoli-cell-only syndrome and complete maturation arrest, while 3 of 14 histograms with hypospermatogenesis demonstrated normal spermatogenesis on histological examination. Additionally 1 of 5 histograms with normal spermatogenesis demonstrated hypospermatogenesis on histological examination.

Conclusions

DNA flow cytometry of the testicular tissue seems to be an objective and quantified method that can be used to investigate spermatogenesis in infertile men. It is also less time-consuming than any histological examination, permits management decisions within 1.5 hours after biopsy and may replace testicular histopathological study. Flow cytometric diagnoses correlated well with histopathological findings.