Hyperplasia and Carcinoma of the Prostate Flashcards
Describe a normal prostate gland?
- In adult, normal weight is 20g
- Retroperitoneal organ
- Encircles the bladder and urethra
The prostate gland is divided into what zones anatomically?
Peripheral
Central
Transitional
Describe the histological regions that make up the prostate gland?
- fibromuscular stroma
2. glandular component
Describe the histology of the glandular component?
Compound tubuloalveolar glands lined by two layers
- Basal layer
- cuboidal epithelium
What controls the growth of the prostate gland?
Testicular androgens
Enlargement of the prostate is characterised by?
hyperplasia of the stromal and glandular epithelial cells
- benign process
Describe the epidemiology of benign prostate hyperplasia?
Common disorder in men over 50 yrs
- Hyperplastic process starts in young age
What zone does BPH usually affect?
transitional zone
- periurethral region
What forms as a result of BPH?
large, discrete nodules
- With resultant urethral obstruction in severe disease
What is the cause of BPH?
Dihydrotestosterone (DHT)
- metabolite of prostate is the mediator of prostatic growth
Describe the aetiopathogenesis of BPH?
- testosterone is converted to dihydrotestosterone by 5 alpha reductase enzyme in prostate stromal cells
- DHT binds to nuclear androgen receptors and signals transcription of growth factors
- DHT 10X potent in causing hyperplasia than testosterone
- can stay bound to androgen receptors for longer
Describe the pathological state of a BPH prostate?
- Can weigh more than 100g
- Composed of nodules of variable sizes
What are the nodules formed by BPH?
- Initial nodules are entirely of stromal cells
- Later epithelial nodules develop
- Mixed nodules (stroma and glandular)
What do these nodules do to surrounding structures?
Urethra compressed into slit like lumen with subsequent obstruction
Describe the pathology of glandular proliferation?
- Small to large to cystically dilated glands with intact basal cells and basement membrane
- Small areas of infarction present
- With surrounding foci of squamous metaplasia present
What are the secondary changes in the bladder?
- Hypertrophy
- Trabeculations
- Diverticular formation
Describe the clinical presentation of BPH?
- secondary changes in bladder
- Hydronephrosis
- excess fluid in the kidneys due to back up of urine - Urinary tract infections
- due to stagnation of urine
What are the clinical symptoms of BPH?
- Difficulty to pass urine: starting the flow and stopping
- Overflow dribbling
- Dysuria
- Frequency
- Nocturia
- Acute urinary retention
- Prone to urinary tract infections
Describe the treatment of BPH?
- 5α-reductase inhibitors
- Inhibit 5α-reductase hence blockin production of DHT - α- adrenergic inhibitors:
- Inhibit α- adrenergic receptors in prostate smooth muscle thereby reducing the muscular tone allowing urine to pass - Surgical correction
What is the most common form of carcinoma of the prostate?
adenocarcinoma of the prostate
- slow growing
Describe the epidemiology of adenocarcinoma of the prostate?
men >50
Which zone is most commonly affected by adenocarcinoma of the prostate?
peripheral zone
How does adenocarcinoma of the prostate come to our attention?
- Sometimes comes to attention with metastatic disease
2. Discovered through screening: Prostate specific antigen (PSA)
What are the risk factors of carcinoma of the prostate?
- Older age
- Positive family history
- Race
- commoner in blacks than white
- Rare in asians - Hormone levels
- Environmental factors: eg diet(fats)
What is a preneoplastic carcinoma of the prostate?
Prostatic intraepithelial neoplasia (PIN)
Describe the aetiopathogenesis of prostatic carcinoma?
- Androgens are believed to play a role in pathogenesis
- Evidenced by reduction in disease burden by orchidectomy - Androgen gene receptor mutation
- Germline mutations of prostate cancer susceptibility genes
Describe the pathology of carcinoma of the prostate?
- 70% arises in peripheral aspects thus palpable on rectal examination
- Cut surface: firm and gritty, if diffusely infiltrative may be difficult to see macroscopically
- Does not form nodules like of BPH
- Irregular glands, lack basal layer and basement membrane is disrupted
Describe the course of the metastases of carcinoma of the prostate?
- Local to adjacent structures
- Haematogenous - to bone and other organs
- Lymph - to regional and distant metastases
