Intraprostatic spermatozoa: zonal distribution and association with atrophy

Intraprostatic spermatozoa (IS) have been demonstrated in only 2 articles in the literature reporting on postmortem prostates. Intraprostatic spermatozoa have not been previously described in radical prostatectomies. This is the first study that describes the presence of IS in radical prostatectomies with prostatic carcinoma (PC) and its association with atrophy.

We examined whole mount sagittal sections from 69 consecutive radical prostatectomy cases for PC. A central section including the seminal vesicle ejaculatory duct urethra complex (SVEDU) from each case was stained with Berg's stain to identify spermatozoa and their location. The extent and the type of atrophy were assessed on the entire prostate by using a grid method. Eighteen cases (26.1%) revealed spermatozoa both in the SVEDU and in the prostate (IS) (group 1). Twenty-two cases (31.9%) showed spermatozoa exclusively in the SVEDU but not in the prostate (group 2). The remaining 29 cases (42.0%) had no spermatozoa in either site. Location of IS was 72.2% peripheral zone, 22.2% central zone, and 5.6% transitional zone. Intraprostatic spermatozoa were frequently seen accompanied by inflammatory infiltrate in the periglandular stroma. The extent of atrophy was greater in group 1 than in group 2 (25.7% versus 15.3%; P = .006). Postatrophic hyperplasia was seen more frequently in group 1 than in group 2 (72.2% versus 40.9%; P = .025). In conclusion, the frequency of IS is 26.1% when including all prostates and 45.0% when including prostates with evidence of residual ejaculate (spermatozoa in the SVEDU), more than previously reported. Intraprostatic spermatozoa are predominantly located in the peripheral zone similar to atrophy and PC. Prostates with IS have larger atrophic areas and increased frequency of postatrophic hyperplasia. The role of IS in the pathogenesis of prostate inflammation and atrophy should be investigated.