A practical guide to prostate cancer diagnosis and management
ABSTRACTScreening, diagnosis, and management of prostate cancer can be complicated, with no clear consensus about key issues. We present our approach, which reflects the guidelines of the American Urological Association (AUA).
KEY POINTS
- The AUA recommends annual screening with both digital rectal examination (DRE) and prostate-specific antigen (PSA) testing starting at age 40 for all men whose life expectancy is more than 10 years. Guidelines from other organizations differ somewhat.
- If the DRE is abnormal or if the PSA level is persistently higher than 2.5 μg/L, then biopsy should be considered.
- In low-risk cases, active surveillance may be acceptable in lieu of immediate treatment. Patient education, accurate disease assessment, and compliance with monitoring are critical considerations.
- The most common primary treatments are active surveillance, prostatectomy, interstitial brachytherapy, external beam radiotherapy, and cryotherapy. Newer ablative and focal therapies may offer an advantage in select patients. Which treatment to use is highly patient-dependent.
- Single-institution, single-surgeon reports and advertisements tend to underestimate rates of impotence after prostatectomy, and as a result patients may have false expectations.
RADICAL PROSTATECTOMY: SEVERAL OPTIONS, EQUIVALENT EFFICACY
Radical prostatectomy is widely used for treating prostate cancer of any risk level. The operation entails removing the prostate and seminal vesicles, as well as the pelvic lymph nodes in patients with intermediate or high-risk cancer.
This procedure was increasingly used in the 1990s with the introduction of PSA screening and nerve-sparing surgical techniques that preserve continence and erectile function.
Radical prostatectomy can be done via a standard open approach or a minimally invasive laparoscopic approach with or without robotic assistance. Open surgery, laparoscopic surgery, and robotic prostatectomy offer equivalent rates of oncologic efficacy, continence, and potency.24 The more experienced the surgeon, the better the outcome is likely to be.
The average biochemical recurrence rate at 5 years after radical prostatectomy is approximately 6% for patients with low-risk cancer, 23% for those with intermediate-risk cancer, and 45% for those with high-risk cancer.25 The rate of death from prostate cancer at 10 years is about 1% for patients with low-risk cancer, 4% for those with intermediate-risk cancer, and 8% for those with high-risk cancer.12
Secondary therapy
Pathologic staging of the surgical specimen after radical prostatectomy yields information that can be beneficial in terms of initiating early secondary therapy.
Patients with node-positive disease should immediately undergo androgen deprivation treatment.26
Evidence of positive surgical margins, seminal vesicle invasion, bladder neck invasion, and extracapsular extension also increase the risk of recurrence. This additional risk can be ascertained via the use of a postoperative nomogram. Patients at high risk of recurrence should be considered for early adjuvant external beam radiotherapy to the surgical field 3 to 6 months after surgery.
Advantages and disadvantages of radical prostatectomy
Advantages of radical prostatectomy include the ability to accurately stage the cancer with the surgical specimen and the ability to remove the pelvic lymph nodes in patients at intermediate and high risk. Another advantage is that postoperative surveillance is straightforward: PSA should become undetectable after surgery, and a measurable increase in PSA represents disease recurrence.
Disadvantages include:
- The risk of surgical complications (reported in 3% to 17% of cases)24
- An average hospital stay of 1 to 3 days (and a typical 3 to 6 weeks before returning to work)
- The need for a Foley catheter for 10 to 14 days
- The risk of incontinence and impotence, which are very distressing to patients.
Postoperative incontinence is typically defined as the need for any type of protective pad for leakage. Up to 70% of patients have incontinence in the first 3 months after surgery, but 82% to 94% of patients regain continence by 12 months.24 A small percentage of patients (3% to 5%) have significant permanent incontinence.
Counseling about postoperative erectile dysfunction
All patients should be counseled about the risk of a postoperative decrease in erectile function, especially those with pre-existing erectile dysfunction. Potency is defined as the ability to have an erection suitable for intercourse (with or without phosphodiesterase type 5 inhibitors) more than 50% of the time. In men with bilateral nerve-sparing open prostatectomy, potency rates at 12 months have been reported between 63% and 81%.13
Data on potency rates vary widely because of differences in how potency was defined, selection bias, and the multifactorial nature of erectile dysfunction. Also, because single-institution, single-surgeon reports and advertisements tend to underestimate rates of impotence after radical prostatectomy by any approach, many patients have false expectations.
INTERSTITIAL BRACHYTHERAPY FOR LOW-RISK CANCERS
Interstitial brachytherapy delivers a localized, high dose (125 to 145 Gy) of radiation to the prostate, with minimal radiation dosing to the bladder, rectum, or other adjacent organs and tissues. “Seeds” or small pellets containing a radioisotope (iodine 125 or palladium 103) are stereotactically implanted through the perineum into the prostate under ultrasonographic guidance. Computerized mapping done before or during surgery helps determine the optimal placement of the seeds, the object being to cover at least 90% of the prostate with 100% of the radiation dose.
In permanent brachytherapy, the implants give off radiation at a low dose rate over weeks to months and are left in place permanently. In temporary brachytherapy, seeds are implanted to deliver a low or high dose rate for a specified period, and then they are removed.
“Implant quality,” ie, delivery of more than 90% of the radiation dose, is a major predictor of success and can depend on both the available instrumentation and the skill of the operator.
Caveats about brachytherapy
The evidence in support of combining androgen deprivation therapy and interstitial brachytherapy is poor, and there is some evidence of increased rates of irritative voiding symptoms,27 so this is generally not recommended.
Interstitial brachytherapy as monotherapy has usually been reserved for patients with low-risk cancer with a low likelihood of extracapsular disease extension or pelvic lymph node involvement. No randomized controlled clinical trial has compared brachytherapy with radical prostatectomy or external beam radiotherapy. One large long-term study reported an 8-year biochemical recurrence rate of 18% in patients with low-risk cancer and 30% in patients with intermediate-risk cancer.28 The long-term efficacy of brachytherapy for intermediate- and high-risk prostate cancer is still under investigation.
