Interindividual Variation in Distribution of Extramural Ganglion Cells in the Male Pelvis: A Semi-Quantitative and Immunohistochemical Study Concerning Nerve-Sparing Pelvic Surgery

We examined distribution and numbers of extramural ganglion cells in the male pelvis, classifying them as sympathetic or parasympathetic. Specimens were obtained from 14 formalin-fixed donated male cadavers. Semiserial sections were processed for histologic examination, and for immunohistochemistry using anti-tyrosine hydroxylase (TH) or anti-peptide histidine isoleucine (PHI). Like those along the sacral sympathetic trunk, most other pelvic ganglion cells were located in and along nerve components. Yet the ganglion cell clusters attached to pelvic viscera accounted for 22% to 38% of ganglion cells. These were seen at the dorsal aspect of the bladder, the bladder/prostate junction, the dorsal aspect of the seminal vesicle, and along the prostate, but not along the extrapelvic pudendal nerve, cavernous tissues including the penile hilum, the rhabdosphincter, retropubic fat or recto-urethral muscle. Two fold interindividual variation was seen for total ganglion cell number (3044 to 6522) in the pelvis. TH-positive and PHI-positive cells intermingled at various ratio in every ganglion cell cluster. Sympathetic TH-positive proportions tended to be site-specific. Pelvic autonomic cells exist not only in nerve components but also along viscera. Even nerve-sparing radical prostatectomy can compromise visceral ganglia. Simple classification of pelvic nerve components as sympathetic or parasympathetic would seem misleading given coexistence of both cell types in a ganglion.