Prostate Cancer Flashcards
What is the function of the prostate gland?
The prostate gland is a specialised type of exocrine gland called and apocrine gland (and merocrine).
The main function of the prostate is to produce prostatic fluid that creates semen when mixed with the sperm produced by the testes.
What are the different phases of development of the normal prostate (4)?
Prostate gland development can be separated into phases :
- hormone-independent from embryonic development up to puberty - enlargement during puberty - hormone-dependent maintenance thereafter in adulthood - And – reactivation of prostate growth in old age – leading to hyperplasia and prostate cancer
What developmental abnormalities can occur with the prostate?
Inflammation, e.g. due to infection - Prostatitis - linked to infertility Dysregulated growth of prostate - Benign: Benign Prostatic Hyperplasia (BPH) - Malignant: Prostate Cancer
What are the symptoms of prostate cancer?
- frequent trips to urinate
- poor urinary stream
- urgent need to urinate
- hesitancy whilst urinating
- lower back pain
blood in the urine (rare)
Where does prostate cancer start?
Prostate tumours originate in those cells that line the lumen, these are the luminal epithelial cells
First they will hyper-proliferate forming what is called prostate intra-epithelial neoplasia (PIN)
And then they will become invasive adenocarcinomas
The prostate cancer cells will divide rapidly, filling the lumen, and then they will begin to invade outwards from the prostate
What are the three methods you can use to detect prostate cancer?
- Digital recta examination (DRE)
- PSA test- blood sample; antibody based assay
- Ultrasound- to detect tumour outside prostate capsule
How does the TNM prostate cancer staging system work?
Done by taking a biopsy and scans
This data is taken and converted into the TNM system
T1: Small, localised tumour
T2 : Palpable tumour by DRE
T3: Escape from prostate gland
T4: local spread to pelvic region
N+: Tumour in lymph nodes
N0- No cancer cells found in any lymph nodes
N1: 1 positive lymph node < 2cm across
N2: >1 positive lymph node or 1 between 2-5cm across
N3: Any positive lymph node >5cm across
M+; metastatic M1a; non-regional lymph nodes M1b; bone M1c; other sites Detected by a PET sca
What is the Gleason grading system?
The Gleason grading system is used to help evaluate the prognosis of men using prostate biopsy samples.
The samples are examined by a clinical histologist.
Prostate cancer staging predicts prognosis and helps guide therapy.
Cancers with a higher Gleason score are more aggressive and have a worse prognosis.
What are the different prostate cancer treatments?
Watchful waiting- Low grade tumour, older patients
- The tumour may never advance enough before the patient dies of old age
Radical prostatectomy- Stage T1 or T2 (confined to prostate gland)
Radical radiotherapy
- External up to T3 (spread past capsule)
- Internal implants (brachytherapy) for T1/2
Hormone therapy
- ± prostatectomy or radical radiotherapy
- Metastatic prostate cancer
What are the current therapies for prostate cancer?
Watchful waiting or active surveillance
Watchful waiting
- Recommended for older men when it’s unlikely the cancer will affect their natural lifespan.
- If the cancer is in its early stages and not causing symptoms, you may decide to delay treatment and wait to see if any symptoms of progressive cancer develop.
Active surveillance
- Aims to avoid unnecessary treatment of harmless cancers while still providing timely treatment for men who need it.
- Active surveillance involves having regular PSA tests, MRI scans and sometimes biopsies to ensure any signs of progression are found as early as possible.
What is a risk factor?
A risk factor is anything that raises your risk of getting the disease
Some risk factors can be changed (exposure / non-heritable), whilst others can’t be changed (heritable).
Having a risk factor, (or several), does not mean that you will get the disease. Many people with one or more risk factors never get cancer, while others who get cancer may have had few or no known risk factors.
What are the risk factors for prostate cancer?
Age- the chances of developing prostate cancer rises significantly after the age of 50
Race/ethnicity- The lifetime risk of being diagnosed with prostate cancer is 13.2-15.0% for White males, while in Black males it is significantly higher (23.5-37.2%), and in Asian males, it is significantly lower (6.3-10.5%)
Geography- Most common in North America, NW Europe, Australia, and on Caribbean islands
Family history
Diet- Slightly higher in those who eat a lot of dairy
Obesity- Get more aggressive prostate cancer
Chemical exposures
Prostate inflammation
(STIs perhaps but controversial studies)
Which genes increase the chances of developing prostate cancer?
Several inherited gene changes seem to increase prostate cancer risk, but they probably account for only a small percentage of cases overall.
Inherited BRCA1 or BRCA2 gene mutations, can also increase prostate cancer risk in men (especially mutations in BRCA2)
Men with Lynch syndrome, a condition caused by inherited gene changes, have an increased risk for a number of cancers, including prostate cancer.
What is PTen?
PTEN is a phosphatase that antagonizes the phosphatidylinositol 3-kinase signalling pathway.
As PTEN is the only known 3′ phosphatase counteracting the PI3K/AKT pathway.
Loss of PTen results in increased growth factor signalling.
What is the TMPRSS2-ERG fusion?
TMPRSS2 gene is normally driven by the androgen receptor transcription factor
TMPRSS2-ERG fusion gene is the most frequent, present in 40% - 80% of prostate cancers in humans.
When the promoter of the gene is fused with the gene coding for the protooncogene ERG there is a strong proliferation signal driven by testosterone
AR now drives proto-oncogene ERG which leads to inappropriate gene activation.
