Denervation of Periurethral Prostatic Tissue by Transurethral Microwave Thermotherapy

Purpose: To determine whether transurethral microwave thermotherapy (TUMT) affects innervation of the urethra and periurethral prostate. Material and methods: Ten patients with troublesome benign prostatic hyperplasia (BPH) were treated with TUMT 1 week prior to transurethral resection of the prostate (TURP). At surgery, a biopsy was taken for histological examination and for immunohistochemical staining of the non-specific neuromarker protein gene product (PGP) 9.5. Control material consisted of identical biopsies from 10 patients undergoing TURP because of BPH, but not subjected to TUMT prior to surgery. Results: Histological examination revealed well-preserved, non-necrotic tissues in all biopsies. Nerve fibres were completely or almost absent in the smooth muscle layer in all but one of the TUMT cases, whereas all non-TUMT patients exhibited large numbers of nerve fibres in the smooth muscle layer. Conclusions: TUMT does affect innervation of the urethra and periurethral prostatic tissue.