Prostate Cancer 5

Question 1

Describe active surveillance for prostate cancer.

Answer 1

• Involves monitoring patients with PSA testing every 3 to 6 months
• Perform surveillance needle biopsies of the prostate every 1-2 years
• Usually reserved for men with less than a 10 year life expectancy and Gleason < 6 disease
  
  • Active surveillance is more risky in patients with a long life expectancy or a higher grade tumor
• Drawbacks of active surveillance are that 30%-40% of patients are “undergraded” or “understaged” on their initial biopsy, and up to half of patients who receive delayed treatment are not cured following delayed treatment

Question 2

Describe the process of radiotherapy for prostate cancer.

Answer 2

• More often used to treat older patients or patients who are not suitable candidates for surgery due to co-morbid medical conditions or because their tumor may be too advanced for complete surgical excision
• There are several options for delivery of radiotherapy:
  
  • external beam (intensity-modulated radiation therapy [IMRT]
  • proton-beam
  • Cyberknife
  • radioactive “seeds” [brachytherapy]
  • combination of external beam and brachytherapy
• Drawbacks of radiotherapy:
  
  • not all cancer cells are sensitive to radiation doses that can be safely delivered
  • geographic misses can spare some cancer cells
  • the genetic changes that caused the first prostate cancer can induce second cancers
  • the risks for bladder (radiation cystitis), rectal (radiation proctitis), and sexual side effects
• If there is tumor recurrence after radiation therapy, the patient cannot safely receive more radiotherapy or radical prostatectomy, and salvage treatment with cryoablation or hormonal therapy is never curative

Question 3

Describe the process of radical prostatectomy as a treatment for prostate cancer.

Answer 3

• Performed as an open surgical procedure (through an abdominal or perineal incision) or as a robotic-assisted laparoscopic approach
• The advantages of surgery are that removal of the prostate gland eiminates the possible development of subsequent de novo cancers arising within the gland
  
  • potentially curative adjuvant or salvage external-beam radiotherapy can be used for patients who have adverse pathology findings or evidence of tumor persistence or recurrence
• The disadvantage of radical prostatectomy is the risk for surgical complications and erectile and urinary dysfunction
  
  • in general, younger patients with a tumor that appears to be highly likely confined to the prostate are the ideal candidates for nerve-sparing (i.e., erection sparing) radical prostatectomy

Question 4

Describe the process of cryoablation used for prostate cancer therapy.

Answer 4

• Can be used as whole-gland or focal therapy
• Argon gas is circulated through hollow needles to freeze the prostate while at the same time, helium gas is circulated to warm the urethra
• It is currently used primarily as salvage treatment of local tumor recurrence following radiotherapy
• The initial results have been suboptimal, with high complication rates, including perineal pain, erectile dysfunction, and rectourethral fistula

Question 5

Describe the process of using HIFU for prostate cancer therapy.

Answer 5

• Can be used as whole-gland or focal therapy
• The prostate tissue is heated up to 100 degrees C, which produces a cavitating lesion over days to months
  
  • It can be repeated if necessary
• A large prostate volume is a limiting (40cc) factor, and a preliminary transurethral resection of the prostate (TURP) is often required
• Complications are similar to those that occur with cryoablation