The Prostate
the prostate is innervated by?
inferior hypogastric plexus
Transitional zone of prostate
Surrounds prostatic urethra
why is prostatic fluid acidic?
contains substances like: - citric acid - spermine - Zn - PSA - spermine these all contribute to *low pH = 6.5*
the prostatic utricle (contracts / relaxes) during sexual arousal
contracts
What does 5alpha reductase do?
converts testosterone to dihydrotestosterone (DHT)
What compensatory changes to other anatomical structures do you expect to occur as a result of an enlarged prostate and why?
*Detrusor muscle*: - thickens (small muscle cell hypertrophy) as it needs to work harder to contract & expel urine *bladder*: - increased collagen deposition ( becomes less elastic & can't stretch) *bladder neurons*: - hypertrophy (to facilitate micturition reflex)
BPH- what would you look for in urine?
*Leukocytes/nitrites* = Urinary tract infection (UTI) *Blood* = Infection/ malignancy/ renal stones/ trauma
prostate cancer- what would you look for in bloods?
*PSA (prostate specific antigen):* - increased levels (normal value varies with age) - can't diff b/w malignant/benign cancer
peripheral zone of prostate (PZ)
*Surrounds central zone* and occupies *posterior* & *lateral* parts of the gland
Q how would you examine?
*early stage*: - median sulcus palpable - single bump may be present *later stage*: - hard prostate - many bumps (uni/bi) - median sulcus absent *pelvic lymphadenopathy*
Trans-Urethral Resection of Prostate (TURP)
*gold standard* - resectoscope inserted thru penis to shave away prostatic tissue
what symptoms will a patient present with if the carcinoma of the prostate has spread to bones?
- Lower back pain - numbness, weakness, tingling (spinal cord compression due to tumor)
Trans-Urethral Vaporisation of Prostate (TUVP)
- removes prostatic tissue using heat from high-voltage electric current - less bleeding, reduces time for catheterisation
BPH symptoms:
- urinary retention - dribbling - hesitancy - frequency of urine inc - nocturia - urinary urgency
why does prostate cancer spread to bones (spine)?
1. due to lymphatic drainage system: pelvic ln --> para-aortic ln --> inguinal ln 2. haematogenous metastases (spread via blood vessels) 3. location 4. venous drainage of prostate is into inferior iliac vein & intervertebral plexus
prostate normal size
20g = 2 *finger breadth* (prostates size is = breadth of your 2 fingers)
Normal PSA level
<4 ng/dL
What is BPH (benign prostatic hyperplasia)?
Abnormal *proliferation* of prostatic *epithelial and stromal* cells --> epithelial lining obstruct the lumen of the glands
Lobes of the prostate gland
Anterior *(isthmus)* --> ant to urethra 2 lateral --> either side of urethra median (middle) --> b/w urethra & ejaculatory duct posterior --> behind urethra & inferior to ejaculatory ducts
carcinoma of (CZ/PZ) constricts urethra first?
CZ
Anterior muscular zone (stroma)
Comprised of dense irregular connective tissue and smooth muscle fibres
T/F: dysuria is specific to BPH
F
T/F: the prostate is mostly fibromuscular
F- *2/3 glandular & 1/3 fibromuscular*
T/F: prostate Is the largest producer of semen
F- *seminal vesicle*
T/F: LUTS is not associated with BPH
F- it is
hypertrophy vs hyperplasia
Hypertrophy: *bigger cell* (more protein) Hyperplasia: *more number* of cells.
If prostatic nerves were damaged, what would happen?
Impotency (erectile dysfunction)
during a BPH examination, the bladder (is/not) palpable
Is palpable
Management of BPH?
Medical: *Alpha-Blockers* --> Tamulosin *5-alpha reductase inhibitors* --> Finasteride Non-medical: exercise, Dietary changes (reduce fizzy drinks, caffeine, alcohol) Surgery: Trans-Urethral Resection of Prostate (TURP) Trans-Urethral Vaporisation of Prostate (TUVP) Holmium laser enucleation of the prostate (HoLEP)
where do most prostatic carcinomas occur?
PZ
T/F : the prostate atrophies as a man ages, and it usually causes no health problems
T
T/F: if the prostate is >20g, the symptoms of BPH manifest
T
Which zone is the site of BPH?
TZ
Q what investigations would you order? Why?
a. *PSA* (>10ng/dL) requires more tests b. *transrectal USS* --> Biopsy (Hypoechoiec region in US) c. *MRI* --> to look for extra-capsular extension (ie extension beyond prostate tissue
prostate surfaces
a. *base* - @ neck of bladder b. *apex* - on sup aspect of ext urethral sphincter c. *anterior surface* - covered by muscles related to the external urethral sphincter d. *posterior surface* - ampulla of rectum e. *inferolateral* - levator ani
A 70 year old gentleman presents to his GP after experiencing three episodes of haematuria. He also describes a 6 week history of lower thoracic/lumbar back pain which now wakes him at night. He takes Tamsulosin to manage ongoing urinary symptoms associated with BPH and Simvatin to manage high cholesterol levels, but is otherwise relatively fit and well. He has a family history of prostate cancer and breast cancer. Q. Initial diagnosis? how can you confirm?
a. *prostate cancer* - pain radiates to lumbar back - haematuria - LUTS - blood in semen - erectile dysfunction
functions of prostate gland
a. *prostatic nerves* --> *penile erection* b. location of *G-spot* --> sexual arousal, orgasm, ejaculation c. produces 5-alpha reductase d. produces prostatic fluid
prostate: a. where does it sit? b. dimensions
a. B/w the *base of the bladder & the penis* b. 3cm x 4cm x 2cm (lbh)
BPH complications
a. BOO (bladder outlet obstruction- urethral compression) b. UTI (LUTS- incomplete bladder emptying) c. kidney damage (pyelonephritis) d. hydronephrosis (due to distension)
which (PZ/CZ/TZ) is a. more glandular b. palpable c. contains mucosal glands d. susceptible to infection
a. PZ b. PZ c. TZ d. PZ
pelvic splanchnic nerves: a. innervates? b. function?
a. bulbourethral glands b. dilate penile arteries, erection
how does a normal prostate feel?
a. firm b. smooth c. presence of median sulcus d. no bumps e. symmetrical
dorsal penile nerve: a. branch of? b. function
a. internal pudendal nerve b. relays cutaneous information (e.g. about the skin) back to the spinal cord
why might haematuria be an indicative factor for prostate cancer?
a. invasion of tumor to nearby tissues b. angiogenesis of tumor c. vessel remodelling (damaged blood vessels due to tumor invasion)
which lobes of prostate: a. are palpable? b. usual site of BPH c. contain no glandular tissue
a. posterior b. median c. anterior
inferior hypogastric plexus constitutes which 2 plexuses?
a. sacral splanchnic (*T12-L2*) - *Sympathetic* b. pelvic splanchnic (*S2-4*) - *parasympathetic*
sacral splanchnic nerves: a. innervates? b. function?
a. seminal vesicles, prostate gland and smooth muscle b. ejaculation
pudendal nerve: a. innervates? b. @spinal level?
a. superficial perineal muscles b. S2-4
why are alpha blockers given @ night?
cause *hypotension*
Prostate lymph drainage
internal iliac and sacral nodes
Prostate arterial supply
internal iliac gives of: a. sup & inf vesicle b. mid rectal c. internal pudendal
PSA- how does it act as a *protease*?
liquefies semen and dissolves cervical mucus to allow free passage of sperm into the vagina
Peri-urethral zone
mucosal & submucosal gland
prostatic fluid enters the urethra thru ________
multiple prostatic ductules
what happens if dorsal penile.n is damaged?
numbness, tingling, aching, pain, or other sensitivity and discomfort
largest Male accessory gland?
prostate
prostate surrounds the _________ urethra
prostatic
accessory glands of male reproductive system
seminal vesicles, prostate gland, bulbourethral glands
prostatic utricle
small indentation in the prostatic urethra
Central zone of prostate (CZ)
surrounds ejaculatory ducts
Prostate venous supply
vesical venous plexus + prostatic venous plexus + internal pudendal + sup & inf vesical ---> Int iliac --> Common iliac --> IVC