Prostate gland & seminal vesicles
Benign lesions/conditions
Benign prostatic hyperplasia

Topic Completed: 1 January 2012

Minor changes: 9 January 2020

Copyright: 2003-2019,, Inc.

PubMed search: benign prostatic hyperplasia [title] "loattrfree full text"[sb] pathology

Ali Amin, M.D.
Page views in 2019: 22,955
Page views in 2020 to date: 13,942
Cite this page: Amin A. Benign prostatic hyperplasia. website. 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)
  • 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)
  • 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.

Missing Image

Stromal nodule,
a normal component of
benign prostatic

Images hosted on other servers:

Various images

Positive stains
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