[Durgical](https://durgical.com/en/) › [DurgiPedia](https://durgical.com/en/durgipedia/) › [Anatomy](https://durgical.com/en/anatomy/) › [Pelvis · Male](https://durgical.com/en/anatomy/region/pelvis/) › Prostate [Reproductive system](https://durgical.com/en/anatomy/system/reproductive-system/) · [Pelvis · Male](https://durgical.com/en/anatomy/region/pelvis/) # Prostate The prostate is a walnut-sized gland below the bladder, around the urethra and in front of the rectum; it makes part of the fluid of semen. [See in 3D →](https://durgical.app/?from=durgipedia&lang=en#region=pelvis&variant=male&select=prostate&side=r) Opens in the Durgical app, no sign-up needed. ## What it is A walnut-sized gland (about 20 g in a young adult) below the bladder, wrapped around the first part of the urethra and lying just in front of the rectum. It is described in zones: peripheral, central and transition, plus the [anterior fibromuscular stroma](https://durgical.com/en/anatomy/isthmus-of-prostate/). ## What it does Makes part of the fluid of semen (including PSA, which keeps semen liquid); its smooth muscle helps push semen out. ## Key points - Its posterior surface lies against the rectum, so it is felt on digital rectal examination: normally rubbery, smooth and symmetric, with a shallow median groove - McNeal zones, not lobes, explain disease: BPH grows from the [transition zone](https://durgical.com/en/anatomy/transition-zone-of-prostate/) around the urethra, while most cancers start in the [peripheral zone](https://durgical.com/en/anatomy/peripheral-zone-of-prostate/) at the back - The neurovascular bundles with the cavernous nerves run along its posterolateral surface; their injury in radical prostatectomy causes erectile dysfunction - Its apex rests on the external urethral sphincter; sparing the sphincter and the length of the membranous urethra is key to continence after surgery ## Key facts **Where** Below the bladder neck, around the prostatic urethra; base up, apex down on the external sphincter; behind the pubic symphysis, in front of the rectum (rectoprostatic or Denonvilliers fascia between) **Blood supply** Prostatic arteries from the inferior vesical artery (also middle rectal and internal pudendal); veins to the prostatic venous plexus, linked to the vertebral plexus (bone metastases) **Nerve** Prostatic plexus (from pelvic plexus): sympathetic T10–L2 contracts smooth muscle (alpha-adrenergic) at emission; parasympathetic S2–S4 drives secretion **Function** Secretes a thin, slightly acidic part of semen with PSA (liquefies the coagulum), citrate and zinc; McNeal zones: peripheral, central, transition, plus anterior fibromuscular stroma ## Relations **Above** Base against the bladder neck; the [seminal vesicles](https://durgical.com/en/anatomy/seminal-gland/) and the ampullae of the [ductus deferens](https://durgical.com/en/anatomy/ductus-deferens/) lie on the back of the [urinary bladder](https://durgical.com/en/anatomy/urinary-bladder/) just above it **Below** Apex on the [external urethral sphincter](https://durgical.com/en/anatomy/female-external-urethral-sphincter/), where the [prostatic urethra](https://durgical.com/en/anatomy/prostatic-urethra-seminal-colliculus/) becomes the [membranous urethra](https://durgical.com/en/anatomy/intermediate-part-of-male-urethra/) **In front** Retropubic (Retzius) space with the dorsal vein complex and the puboprostatic ligaments, behind the [pubic symphysis](https://durgical.com/en/anatomy/pubic-symphysis/) **Behind** [Rectum](https://durgical.com/en/anatomy/rectum/), separated by the rectoprostatic (Denonvilliers) fascia, the plane used in radical prostatectomy and in rectal cancer surgery **Lateral** Prostatic venous plexus, neurovascular bundles and the [levator ani](https://durgical.com/en/anatomy/levator-ani/) ([pubococcygeus](https://durgical.com/en/anatomy/pubococcygeus-muscle/) fibres) of the pelvic floor **Contents** Prostatic urethra and the two [ejaculatory ducts](https://durgical.com/en/anatomy/ejaculatory-duct/), which pass obliquely through the [central zone](https://durgical.com/en/anatomy/central-zone-of-prostate/) to open on the verumontanum ## How to find it On digital rectal examination, with the person on the left side and knees drawn up or standing bent forward, the gland is felt through the front wall of the rectum a few centimetres in. Size, consistency, symmetry, the median groove, nodules and tenderness are noted; the top of the gland and the seminal vesicles are usually out of reach. ## Examination - Digital rectal examination: a hard, irregular nodule or a lost median groove suggests cancer; smooth, symmetric, rubbery enlargement suggests BPH; a very tender, warm, boggy gland suggests acute bacterial prostatitis ## On imaging Transrectal ultrasound measures volume and guides biopsy (through the rectum or the perineum). Multiparametric MRI shows the zones best and is reported with PI-RADS, a 1–5 scale of how likely a clinically significant cancer is. The blood PSA is context only: it can rise with BPH, prostatitis and cancer. ## Common problems - Benign prostatic hyperplasia (BPH): growth with age, mainly of the transition zone, that squeezes the urethra. - Prostate cancer, one of the most common cancers in men; most start in the peripheral zone. - Prostatitis (infection or inflammation). ## How it is diagnosed Digital rectal examination; PSA blood test; MRI and a needle biopsy if cancer is suspected; ultrasound. ## Treatment - Medicines for BPH (alpha-blockers, 5-alpha-reductase inhibitors); surgery through the urethra (TURP) if needed. - Prostate cancer: active surveillance, radical prostatectomy or radiotherapy, depending on the risk. ## Clinical notes - BPH causes lower urinary tract symptoms: weak stream, hesitancy, straining, incomplete emptying, frequency, nocturia and urgency; it can end in urinary retention, infection or bladder stones - Transurethral resection of the prostate (TURP) removes transition-zone tissue from inside the urethra; retrograde ejaculation is common afterwards because the bladder neck no longer closes - Radical prostatectomy removes the prostate and seminal vesicles and joins the bladder neck to the urethra; erectile dysfunction (cavernous nerves) and urinary incontinence (sphincter) are its main long-term effects, lessened by nerve-sparing technique - Prostatitis ranges from acute bacterial infection with fever and perineal pain to chronic pelvic pain without proven infection ## Development Grows from endodermal buds of the urogenital sinus under dihydrotestosterone; this androgen dependence explains why 5-alpha-reductase inhibitors shrink BPH and why androgen deprivation is used in advanced cancer. ## Memory aid Peripheral is Palpable (cancer, felt on rectal exam); Transition is TURP (BPH, resected from inside). ## Related conditions - [Benign prostatic hyperplasia](https://durgical.com/en/conditions/benign-prostatic-hyperplasia/) - [Prostate cancer](https://durgical.com/en/conditions/prostate-cancer/) - [Prostatitis](https://durgical.com/en/conditions/prostatitis/) - [Acute urinary retention](https://durgical.com/en/conditions/acute-urinary-retention/) ## Test yourself Think of the answer, then tap the question to see it. ## In which McNeal zones do BPH and most prostate cancers arise? BPH from the transition zone around the urethra; most cancers from the peripheral zone at the back (peripheral is palpable). ## What findings on digital rectal examination suggest cancer, BPH and acute prostatitis? Cancer: hard irregular nodule or lost median groove. BPH: smooth, symmetric rubbery enlargement. Acute prostatitis: very tender, warm, boggy gland. ## What are the main long-term effects of radical prostatectomy, and which structures explain them? Erectile dysfunction (cavernous nerves in the neurovascular bundles) and urinary incontinence (external sphincter). ## Why is retrograde ejaculation common after TURP? The bladder neck no longer closes once transition-zone tissue is removed from inside the urethra. ## Which fascia separates the prostate from the rectum, and why does it matter surgically? The rectoprostatic (Denonvilliers) fascia; it is the plane used in radical prostatectomy and rectal cancer surgery. [Add to my cards (5)](https://durgical.app/estudiar/?add=/en/anatomy/prostate/) Educational information, not medical advice. For any symptom, see a health professional. ## Its names **Official Latin (TA2)** prostata **Official Spanish (DeCS)** Próstata **English (TA2)** Prostate **Also called** prostate gland ## Related - [Urinary bladder](https://durgical.com/en/anatomy/urinary-bladder/) - [Rectum](https://durgical.com/en/anatomy/rectum/) - [Peripheral zone](https://durgical.com/en/anatomy/peripheral-zone-of-prostate/) - [Central zone](https://durgical.com/en/anatomy/central-zone-of-prostate/) - [Transition zone](https://durgical.com/en/anatomy/transition-zone-of-prostate/) - [Anterior fibromuscular stroma](https://durgical.com/en/anatomy/isthmus-of-prostate/) - [Prostatic urethra](https://durgical.com/en/anatomy/prostatic-urethra-seminal-colliculus/) - [Pelvic plexus and cavernous nerves](https://durgical.com/en/anatomy/inferior-hypogastric-plexus/) Sources: [Anatomy, Abdomen and Pelvis, Prostate](https://www.ncbi.nlm.nih.gov/books/NBK540987/). ## **Spotted a mistake?** We are always improving for the community. Tell us what is wrong and our team will review it. Report a mistake Representative model, for educational purposes only. --- Source: https://durgical.com/en/anatomy/prostate/ License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Cite as: DurgiPedia (durgical.com), https://durgical.com/en/anatomy/prostate/