Prostate Cancer 2

Question 1

What is the physiologic function of the prostate gland? What happens when this function goes awry?

Answer 1

• To produce prostate-specific antigen (PSA)
  
  • enzyme that liquefies the seminal coagulum
  • facilitates the fertilization process
• PSA is normally secreted in a polar fashion from the epithelium of the prostate acini into the prostate ductal system
• When the normal physiology and architecture of prostatic tissue is perturbed by cancer, inflammation, or benign hyperplasia (BPH), the polar secretion of PSA is altered
  
  • PSA diffuses through the basement membrane of the prostatic glands (called acini) into the bloodstream.

Question 2

What is a good diagnostic test for prostate cancer? What are some of its downsides?

Answer 2

• Serum PSA test is a useful first-line screening test for prostate cancer
• However, serum PSA levels also can be increased by benign conditions such as prostatitis, BPH, ejaculation or digital rectal examination (DRE) of the prostate

Question 3

What are the findings of prostate cancer on digital rectal examination (DRE)

Answer 3

• Because most of the prostatic acini are situated in the peripheral zone of the prostate, approximately 70% of prostate cancers arise in this region
• On digital rectal examination (DRE) of the prostate, prostate cancer has a hard consistency in contrast to the soft, yielding consistency of the normal prostate or BPH tissue
• Thus, the DRE may reveal regions of induration (called “nodules”), irregularity, or asymmetry
• DRE is a complementary screening test for prostate cancer, as together, they greatly enhance the early detection of prostate cancer

Question 4

What are the downsides of serum PSA and DRE for prostate cancer detection? What is a good confirmatory test?

Answer 4

• Neither DRE nor PSA is specific for cancer, and both may yield false positive or false negative results
• Multiparametric magnetic resonance imaging (MRI) scans are also used in deciding whether or not to perform a needle biopsy of the prostate

Question 5

What are some important symptoms of advanced prostate cancer?

Answer 5

• Lymph node enlargement
• Bone pain
• Urinary tract obstruction