Andrology and Interventional Radiology Unit, Mayanei Hayeshua Medical Center, Bnei Brak, Israel.
Department of Condensed Matter Physics, The Weizmann Institute of Science, Rehovot, Israel.
Prostate. 2020 Nov;80(15):1297-1303. doi: 10.1002/pros.24051. Epub 2020 Aug 24.
Age-dependent increase in the incidence of benign prostatic hyperplasia (BPH) and prostate cancer (PCa) are both related to cell proliferation and survival controlled by intraprostatic free testosterone (FT) concentration. Paradoxically, BPH and PCa occur as circulating testosterone levels decrease, so any possible relationship between testosterone levels and development of BPH and PCa remains obscure.
In BPH the enlarging prostate is exposed to high testosterone levels arriving directly from the testes at concentrations about hundredfold higher than systemic FT. This occurs because venous blood from the testes is diverted into the prostate due to the elevated hydrostatic pressure of blood in the internal spermatic veins (ISVs). Elevated pressure is caused by the destruction of one-way valves (clinically detected as varicocele), a unique phenomenon related to human erect posture. While standing, human males are ISVs vertically oriented, resulting in high intraluminal hydrostatic pressures-a phenomenon not found in quadrupeds. In this communication, we demonstrate the fluid mechanics' phenomena at the basis of varicocele leading to prostate pathology.
So far, varicocele has been studied mostly for its etiologic role in male infertility and, thus, for its effects on the testes. It is becoming clear that varicocele is a major etiologic factor in BPH and likely also in PCa. Restoring normal testicular venous pressure by treatment of the abnormal ISV's in varicocele has been shown to avert the flow from the prostate with the effect of reducing prostate volume, alleviating symptoms of BPH, and increasing concentrations of circulating FT.
良性前列腺增生（BPH）和前列腺癌（PCa）的发病率随年龄增长而增加，这两者都与前列腺内游离睾酮（FT）浓度控制的细胞增殖和存活有关。矛盾的是，BPH 和 PCa 发生时循环睾酮水平下降，因此睾酮水平与 BPH 和 PCa 发展之间的任何可能关系仍然不清楚。
在 BPH 中，不断增大的前列腺暴露于来自睾丸的高浓度睾酮中，其浓度比全身 FT 高约 100 倍。这是因为睾丸的静脉血由于内部精索静脉（ISV）中的血压升高而被分流到前列腺中。升高的压力是由单向阀的破坏引起的（临床上表现为精索静脉曲张），这是一种与人类直立姿势相关的独特现象。当人站立时，ISV 呈垂直方向，导致管腔内静水压力升高——这种现象在四足动物中不存在。在本通讯中，我们展示了精索静脉曲张导致前列腺病变的基础流体力学现象。
到目前为止，精索静脉曲张主要因其在男性不育中的病因作用而受到研究，因此其对睾丸的影响也受到研究。越来越清楚的是，精索静脉曲张是 BPH 的主要病因因素，可能也是 PCa 的主要病因因素。通过治疗精索静脉曲张中的异常 ISV 来恢复正常睾丸静脉压力，已被证明可以阻止血流从前列腺流出，从而减少前列腺体积、缓解 BPH 症状并增加循环 FT 浓度。
