Prostate Cancer

Incidence

Approximately 20,000 new cases of prostate cancer are diagnosed in Australia annually. There are 3,300 deaths from prostate cancer each year.

One in nine men in Australia will develop prostate cancer in their lifetime. It is the most common cancer in Australian men and the second most common cause of cancer deaths in men.

PSA

Prostate Specific Antigen (PSA) is a glycoprotein secreted by the epithelial cells of the prostate gland. PSA is produced for the ejaculate, to liquify semen and allow sperm to swim freely. PSA is present in small quantities in the serum of men with healthy prostates but is often elevated in the presence of prostate cancer and in other conditions such as chronic prostatitis or urinary tract infection.

PSA Screening

Annual PSA testing and digital rectal examination have improved the ability to detect early, organ confined prostate cancer.

PSA screening has allowed us to diagnose prostate cancer before it has spread. Overtreating prostate cancer is a bigger problem than over-screening. While screening can detect prostate cancers that need to be treated earlier, it can also detect slow growing cancers which could be monitored every six months to a year for the rest of a patient's life. The current recommendation is that all men aged 50 or older with a life expectancy of at least 10 years, should discuss with their GP the benefits of a having a PSA test. Those men with a first degree relative who has been diagnosed with prostate cancer at the age of 65 or younger should commence screening at the age of 45 years.

Diagnosis

An elevated PSA level is not diagnostic of prostate cancer. Prostate cancer can only be diagnosed with a prostate biopsy which provides tissue for the pathologist to examine microscopically. Prostate biopsies are performed using transrectal ultrasound and can be performed under local anaesthetic or with a general anaesthetic on a day only basis.

Clinically Localized Prostate Cancer

Prostate cancer cells grow locally within the prostate gradually spreading through the sides of the prostate into the surrounding tissues. It then spreads into local lymph glands and also into the adjacent seminal vesicles and peri-prostatic fat. It spreads to the bones particularly the lumbar spine. The best chance for curing prostate cancer is when it is confined within the prostate. The further it tracks through the sides of the prostate the less likely the chance of cure.

MRI Prostate

The use of MRI in those patients who have had negative prostate biopsies previously and whose PSA continues to rise is gaining increasing relevance. MRI may detect suspicious areas which can be directly targeted and help identify areas of cancer within the prostate which have been missed by trans-rectal ultrasound guided biopsies. MRI also plays an important role in preoperative assessment of tumour extent within the prostate, extra-capsular extension or seminal vesicle invasion.

Treatment

The decision to treat clinically localized prostate cancer is dependent upon the patient's age, the PSA level, the grade of the cancer, and a patient's pre-existing comorbidities which may limit his survival to less than 10 years. Definitive treatments to attempt to cure prostate cancer are for those with a life expectancy of 10 years or more.

The specific treatments which may cure prostate cancer are surgery or radiotherapy. Hormone therapy is not curative.

Surgery for Prostate Cancer

There are various surgical techniques that one can use, but the results of all of these techniques are similar when compared with respect to cancer clearance rates, maintenance of bladder control and preservation of erectile function.

The surgical options are open retropubic prostatectomy, radical perineal prostatectomy, laparoscopic prostatectomy and robot assisted laparoscopic prostatectomy.

Radiotherapy

Radiotherapy can be performed by utilizing external beam radiation therapy, radioactive seeds or high density radiotherapy in which case radioactive rods are temporarily inserted into the prostate and a lower dose of external beam radiation therapy administered.

Radical Perineal Prostatectomy

Radical perineal prostatectomy is a time-honoured surgical technique for removing the cancerous prostate. It is the original radical prostatectomy surgical technique and was followed by open prostatectomy and the more recent endoscopic techniques. Radical perineal prostatectomy is considered minimally invasive surgery as are the laparoscopic techniques. Radical perineal prostatectomy has the same cancer outcomes as open and robotic prostatectomy, with minimal pain, minimal blood loss and early return to work. To read more on radical perineal prostatectomy go to:

Alternative Therapy

The alternatives to radical prostatectomy are observation, hormone deprivation and radiation therapy. Observation or hormone deprivation are not curative and the patients for whom this is a good option are those patients with less than five years of life expectancy, patients who are over 70-years-old with a well differentiated cancer, or patients who are at a high risk for surgery and refuse radiotherapy. Radiation therapy however may be curative and has an equivalent five and 10 year survival. The recurrence rates with radiation therapy are bimodal with initial recurrences within one to two years of treatment and a delayed peak at five to seven years after treatment.