Electrophysiological differences between typical and dense benign prostatic hyperplasia tissues retrieved after holmium laser enucleation of the prostate

Abstract

Electrophysiological differences between typical and dense (beach ball) benign prostatic hyperplasia (BPH) tissues were investigated using a needle device with a micro-electrical impedance spectroscopy (µEIS) sensor. Ten pieces of typical BPH tissues and beach balls were collected from ten patients during the morcellation procedure of Holmium laser enucleation of the prostate. Their impedance was measured at a frequency range from 100 to 1 MHz using the µEIS-on-a-needle (µEoN). The impedance data (magnitude) were compared between the two tissue types and their correlation with the pathologic features was investigated. The mean magnitude of the beach balls tended to be larger than that of the typical BPH tissues at all investigated frequencies. Notably, significantly larger magnitudes were observed in the beach balls at the frequencies higher than 15.9 kHz (p ≤ 0.02). The variation of mean log-transformed magnitudes by frequency was significantly different between both tissue types (p < 0.001). The pathologic features of the beach balls presented pure stromal nodules of nodular hyperplasia, while the typical BPH tissues presented mixed epithelial-stromal nodules. The impedance difference between typical BPH tissues and beach balls is assumed to be attributed to the amount of their stromal content.