Prostate Cancer (2) Flashcards
Risk factors for developing prostate cancer
Age (over 65)
-65% of men over 65 develop prostate cancer
Race
-highest in African Americans (followed by white, then Asian)
Genetics
-BRCA 1 or 2 +
Family history
-immediate family (brother/father) = 2x risk
Diet
-high red meat consumption (red meat increases testosterone)
What is the most common type of cancer to occur in the prostate
Adenocarcinoma (95% of prostate cancers) - arises in the cells of glands
2 Screening Methods for Prostate Cancer
- Digital Rectal Exam
-done annually during physical - physician places finger in rectum and feels to see if the prostate is enlarged
-but just because the rectum is enlarged doesn’t mean its cancer, there could be other reasons - BPH, age, high levels of red meat, bike or horse riding, recent sexual intercourse, etc. - PSA
-prostate specific antigen - this is produced only from the prostate gland, and more of it is produced if the prostate is enlarged
-if PSA is greater than 10 ng/mL - patient should undergo further testing, or if patient is younger (age 40-60) and PSA is greater than 4 ng/mL- they should undergo further testing
Again, there could be other reasons for enlarged prostate (and therefore elevated PSA) - but just a good reason to do further screening (MRI/biopsy)
Prostate cancer presentation/symptoms
Sexual dysfunction
Bladder habit changes (prostate is around the urethra- so when it is larger it makes is harder to expel urine)
^but these are just symptoms of an enlarged prostate, not necessarily cancer …
These are symptoms that suggest cancer…
-blood in the urine
-pain
-weakness or numbness of legs (because it metastasizes to the bone)
Metastatic sites of prostate cancer
Most common: bone
Also - liver and lung
Prostate cancer staging
Previously - Gleason’s scale was used
-score from 1-5 based on cell differentiation
-biopsy was done, cells were looked at under the microscope and the worst 2 were chosen and the score were added up (so the total score could range from 2-10)
This scoring tool didn’t work well, so there is a new prostate grading system
-based on the traditional Gleason’s scale, but is overall rated 1-5 grades
Prostate cancer treatment approach
Treatment isn’t necessarily based on stage, it is based on if it is early or advanced disease or recurrent disease
If early stage - curative therapy ….
-observation (if prostate is enlarged/PSA high, but MRI/biopsy are normal)
-radiation
-radical prostatectomy (remove prostate)
If advanced stage…
-androgen ablation (deprivation of testosterone)
-orchiectomy (removal of testis to decrease testosterone)
If recurrent disease (despite other treatments) …
-chemotherapy
-more radiation
Early stage treatment differs slightly based on what?
How high risk the patient is
(early stage is observation, radiation, and surgery - there are differences in the radiation and surgery based on if the patient is “very low risk” or “intermediate risk”)
Very low risk…
-grade 1
-PSA < 10 ng/mL
Intermediate risk…
-grade 2-3
-PSA 10-20 ng/mL
Early stage treatment
Observation, radiation, surgery
Radiation
-for very low risk: conventional beam radiation (from external source)
-for intermediate risk: brachytherapy (radiation occurs from the inside, something is placed inside and becomes radioactive)
Surgery
-for very low risk: TURP (transurethral resection of the prostate) - go up the urethra to remove the piece of the prostate that is cancerous
-for intermediate risk: prostatectomy - complete removal of the prostate through the rectum (many complications)
What are side effects of early stage radiation?
For external beam radiation (low risk patients)…
-dysuria, diarrhea, hematuria (blood in urine), cystitis, erectile dysfunction
For brachytherapy (intermediate risk patients)…
-obstructive urinary problems
What are complications of prostatectomy?
(removal of the prostate - done through the rectum so there are more complications than TURP)
Incontinence
Cystitis
Erectile dysfunction
Advanced stage treatment
Orchiectomy
-removal of the testis to decrease testosterone
-this has psychological and cosmetic consequences - so patients often opt to try other therapies
GnRH agonist + antiandrogen
or
GnRH antagonist
-but these treatments also have ADRs including impotence, bone density loss, weakness, and hot flashes
How do GnRH agonists vs antagonists work?
Antagonists will directly block GnRH receptors -causing a decrease in LH and therefore testosterone production
-immediate action
-can be used alone
Agonists - work through the negative feedback loop… they first cause an increase in testosterone, but eventually will result in downregulation of GnRH receptors due to the negative feedback
-because they take time to do this and because of the initial surge in testosterone, they must be used with a antiandrogen
Which 2 drugs are GnRH AGONISTS
Leuprolide (IM injection)
Goserelin (SC injection)
(REMEMBER - these need to be used with an antiandrogen)
GnRH agonist ADRs and management
Initial tumor flare - (due to testosterone surge) - this is why they need to be used with an antiandrogen to prevent this
Decreased bone density (they also decrease estrogen production) - supplement with calcium/vitamin D
QT prolongation (check for DDIs)
Hot flashes, impotence, gynecomastia, bone pain
