Lecture 8: Prostate Pathology Flashcards
What is the function of the prostate gland?
It is the exocrine compound tubule-alveolar gland
Function is to secrete a slightly ALKALINE fluid (to counter acidic vagina)
Milky, or white in appearance
Usually constitutes 20-30% of semen volume along with spermatozoa and seminal vesicle fluid
Sprematozoa that is expelled in prostatic fluid have better motility, longer survival and better protection of DNA
What is the McNeal Anatomic model for prostate?
- Glandular Compartments
2. Non-glandular compartments
What are in the GLANDULAR compartments for the Mcneal Anatomic model for the prostate?
- Peripheral Zone (PZ)
- Central Zone (CZ)
- Transitional Zone (TZ)
- Periurethral gland Region (PU)
What are in the non-glandular compartments?
- Anterior fibromuscular stroma
2. Preprostatic Sphincter
What is the “lobe” classification of prostate used in?
Used for anatomy NOT for pathology Anterior lobe (isthmus) = part of transitional zone Posterior lobe = peripheral zone Lateral lobe spans all zones Median lobe = part of central zone
What does PUGR stand for?
Periurethral gland region
One of the 4 zones
What does PU stand for? Significance?
Prostatic urethra
Used by McNeal as key anatomic landmark
What does UP stand for?
Proximal prostatic urethra
What does UD stand for?
Distal prostatic urethera
What does SV stand for?
Seminal vesicle
Where do the ejaculatory ducts pass?
The central zone
What are the key characteristics of the peripheral zone?
Approximately 70% of normal gland in young men
Sub-capsular portion of the POSTERIOR aspect of the gland that surrounds the distal urethra
70-80% of prostatic cancers originate from the peripheral zone
What is the key characteristics of Central zone?
25% of normal gland
Surrounds the ejaculatory duct
Secondary involvement in prostatic cancers
What are the key characteristics of the transition zone?
5% of normal gand
Responsible for BENIGN PROSTATIC HYPERPLASIA
10-20% of prostate cancers
Surrounds proximal urethra
What are the key characteristics of the anterior fibro-muscular zone?
5%
Devoid of glandular components
Composed only of muscle and fibrous tissue
What part of the prostate is responsible for benign prostatic hyperplasia (BPH)?
Transitional zone (TZ)
What are the two layers of cells in the prostate?
- Basement membrane
2. Epithelial layer
What does the normal microscopic anatomy of prostate look like?
- branching tubuloalveolar system
- originate from urethra in curvilinear pattern
- apical and basal layer in glands
- FEW endocrine cells
- glands sit in fibromuscular stroma
What types of cells in prostate?
- secretory cells
- Basal cells
- Endocrine-paracrine cells
What does PSA stand for?
Prostate specific antigen
…could also be misconstrued as prostate-specific
actin
What is the definition of BPH?
Nodular prostate enlargement due to cellular proliferation of prostatic glands and stroma associated with lower UTI symptoms
LUTS = lower urinary tract symptoms
What is the etiology of BPH?
Pathophysiology remains poorly understood
Perhaps hormonal alterations play a major role (accumulation of testosterone?)
What are risk factors of BPH?
Aging
Family history
Estrogen
What is the prevalence of BPH?
50% of men in 50s
80% men in their 80s
What is the most common cause of non cancerous rise in PSA?
BPH
PSA – prostate-specifc antigen
What is the significance of LUTS features?
Without lower urinary tract symptoms, glandular and stromal proliferation is NOT BPH
What is the hallmark of BPH?
Nodular prostatic enlargement
Hyperplastic nodules
-mainly centered on proximal prostatic urethra
-involve transition zone and submucosal compartment
When do you biopsy patients who are asymptomatic??
Increased serum PSA
Abnormal digital rectal exam
Peripheral zone is enlarged (posterior)
This is prostate carcinoma
What is PCA?
Prostate carcinoma
What is DRE?
Digital Rectal exam
What is the epidemiology of PCA?
6th most common cancer in world
PCA is the MOST COMMON malignancy in men
Affects AFRICAN-AMERICANS much more
2nd most lethal cancer after lung cancer
What are risk factors for PCA?
Red meat Animal products (heterocyclic amine content?)
What are the two types of PCA?
- Asymptomatic
2. Symptomatic
What are the characteristics of Symptomatic Prostate carcinoma?
- Obstructive bladder symptoms
- transition zone cancer therefore may have had cancers before
- Pelvic pain
- local extension
- Bone pain
- bone metastasis
What does the term PCA include?
- acinar adenocarcinoma
- ductal adenocarcinoma
- adenosquamous and squamous cell carcinoma
- basaloid and adenoid cystic carcinoma
- small cell carcinoma
- sarcomatoid carcinomas
What produces prostate specific antigen? Purpose?
It is synthesized by secretory cells of the epithelium
Increased diffusion into serum when basement membrane is breached by PCA
Liquefies semen and increases motility
What are the macroscopic features of PCA?
Lack of necrosis or hemorrhage
No sharp borders
Indurated yellow mass
Is there a PSA cut off at which a man can be guaranteed to be free from prostate cancer?
No
Where do PCA usually arise from?
Peripheral zone (75-80%)
Tranistional zone responsible for 15-25%
50% are multifocal
What are the categories of microscopic features of PCA?
- Architectural featuers
- Nuclear and cytoplasmic features
- Intraluminal features
- Pathognomic features
What are the pathognomonic features of PCA?
- Circumferential perineural invasion
- collagenous micronodules
- glomerulations
- growth within adipose tissue
What is corpora amylacea?
Prostatic concretions…suggests benign cancer
Hyaline masses of unknown significance found in prostate gland, neuroglia and pulmonary alveoli
-derived from secretions and increase with age
What is the verumontanum?
AKA seminal colliculus
An important landmark near the ENTRANCE of the seminal vesicles
Means mountain ridge in Latin
What is Gleason Grade 1?
Tightly cohesive nodule of WELL FORMED glands
What is Gleason Grade 2?
Loosely cohesive nodule of well formed glands
What is Gleason Grade 3?
Haphazard infiltration of irregular glands
What is Gleason Grade 4?
Large cribriform plates and small sheets of cells with glandular lumens
No space where the glands should be..
What is Gleason Grade 5?
Sheets of cells WITHOUT any gland formation
What is the gleason score?
GS 5-6 = lower progression rates
GS 7-10 = worse prognosis
Predictive value of GS enhanced when combined with PSA level and DRE findings
What are the genes implicated in prostate cancer?
Deletions in 8p PTEN P53 RB1
