Prostate gland & seminal vesicles
Benign lesions/conditions
Benign prostatic hyperplasia
Author: Ali Amin, M.D.
Topic Completed: 1 January 2012
Minor changes: 9 January 2020
Copyright: 2003-2019, PathologyOutlines.com, Inc.
PubMed search: benign prostatic hyperplasia [title] "loattrfree full text"[sb] pathology
Table of Contents
Definition / general | Pathophysiology | Clinical features | Treatment | Gross description | Gross images | Microscopic (histologic) description | Microscopic (histologic) images | Positive stainsCite this page: Amin A. Benign prostatic hyperplasia. PathologyOutlines.com website. https://www.pathologyoutlines.com/topic/prostatenodhyper.html. Accessed August 3rd, 2020.
Definition / general
- Also known as benign prostatic hypertrophy (BPH)
- Present in 20% of men at age 40, 50% at age 50 and 70% at age 60
- No correlation between histology and symptoms (50% with histologic findings have clinical enlargement of prostate, only 50% of these have symptoms)
- Incidence higher in African Americans
- Recommended to not use this diagnosis on biopsies due to lack of correlation with obstructive symptoms; however, presence of stromal nodules does correlate with increased prostatic weight (Hum Pathol 2002;33:796)
Pathophysiology
- Requires intact testes
- Testosterone and dihydrotestosterone (DHT, 10x more potent than testosterone because it dissociates from receptor more slowly) bind nuclear androgen receptors in stromal and epithelial cells, causing growth factor activation
- Stromal cells produce 5 alpha reductase (converts testosterone to DHT)
- Estradiol, increased in aging men, may also increase androgen receptors
Clinical features
- Periurethral (transitional zone) nodules may compress urethra and cause obstructive symptoms of urinary tract infection, obstruction, acute urinary retention, bladder hypertrophy, trabeculation
- Diverticula NOT associated with prostatic adenocarcinoma, although it may develop in residual gland after TURP
- One study showed transition from nodular hyperplasia to transition zone adenocarcinoma (Hum Pathol 2003;34:228)
Treatment
- Transurethral resection of prostate (TURP, #2 most common surgery after cataracts in men > 65, 400,000 per year in US)
- Suprapubic prostatectomy
- Androgen antagonists, smooth muscle relaxers (5 alpha reductase inhibitors decrease DHT and in many cases, prostatic volume and symptoms), minimally invasive treatment (i.e. ethanol ablation in Europe)
- Note: may recur after TURP as peripheral tissue expands to surround the prostatic urethra
Gross description
- Large, discrete, periurethral nodules
- Mean size of surgical prostatectomy specimens is 100 g
- Usually in transitional and periurethral zones (5% in peripheral zone), although enlarged prostate may compress other zones
- Glandular hyperplasia is yellow-pink, soft, oozing prostatic fluids
- Stromal hyperplasia is gray, tough
Gross images
Images hosted on other servers:
Various images
Microscopic (histologic) description
- Hyperplasia of glandular and stromal tissue with papillary buds, infoldings and cysts
- Associated with squamous metaplasia and infarction
- Begins around urethra where ejaculatory ducts enter prostate (transitional or periurethral zone)
- Basal cell layer is continuous
- Stromal changes are increased smooth muscle, lymphocytes and ducts (not associated with infectious process of prostatitis in most cases), reduced elastic tissue
- Variations include sclerosing adenosis, fibroadenoma-like and phyllodes-like hyperplasia, leiomyoma-like nodules, fibromyxoid nodules; associated with infarct
Microscopic (histologic) images
Contributed by Grzegorz Gurda M.D., Ph.D.,
Gundersen Health Systems, Wisconsin
Nodular hyperplasia (BPH), 4x, 10x, 20x
Contributed by
Kenneth Iczkowski, M.D.
Stromal nodule,
a normal component of
benign prostatic
hyperplasia
Images hosted on other servers:
Various images
Positive stains
