The prostate is a donut shaped gland which lies at the base of the bladder. It surrounds the outlet pipe (urethra) which drains urine from the bladder through the penis. It grows, slowly at first, from at birth 1g and doubling in size to 2g by age 25. By age 50 however the prostate has grown 10 fold to 25g and by age 75 it reaches around 30g.
The job of the prostate is to make nutritional fluid, about 30% of the total fluid which accompanies sperm in ejaculation. Without prostate fluid those sperms wouldn't get very far!
There are 3 major things that can go wrong with the prostate. It can either
- enlarge – "Benign Prostatic Hyperplasia" or "BPH" is the technical term
- develop cancer or
- become inflamed – known as "prostatitis"
The detection and treatment of prostate disease is controversial and is best demonstrated by the case of Mick who is 50. Mick comes along to his GP for a prostate check...
Mick: G'day doc, I've come to get my prostate checked.
Doctor Bob: Umm... prostate?
Mick: Yes, I've come for the prostate blood test (enthusiastically)
Doctor Bob: You seem very keen to have this done?
Mick: Too right. I heard about prostate disease on the television – 60 Minutes I think? And I think my dad, who is 75, may have prostate cancer but he doesn't talk about it much. I want to make sure I don't get it either.
Doctor Bob: Do you know the risk factors for prostate cancer?
Mick: Not really, but I guess having a father with prostate cancer could be a risk.
Doctor Bob: Yep, you're right. Family history is important especially if your father develops prostate cancer before the age of 55. Other risk factors include age – the older you are the greater chance of developing this cancer – smoking and possibly vasectomy. Prostate cancer is rare before age 50 but it is the second most common cancer for men aged 60-69, and the most common cancer thereafter. Do you know what the symptoms are?
Mick: No, no, not really.
Doctor Bob: Well, first you should know that blokes with prostate cancer often have no symptoms. But when they do occur, the 3 most common symptoms are all related to urine flow – poor stream, hesitancy in starting urine flow and dribbling after stopping. Another important symptom is getting up to pass urine at night. At the same time, you should know that these symptoms are usually due to benign enlargement and not cancer.
Mick: Well, I'm glad you said that, I was starting to shit myself!
Doctor Bob: Why? Do you have some of these symptoms?
Mick: Well, put it this way…I can't piss over the back fence any more and my stream is generally OK but I do get up at night to pass urine at least twice at night.
Doctor Bob: We should check that out then.
Mick: So is there a screening test I take?
Doctor Bob: Let me say something about screening. Screening involves looking for evidence of prostate cancer in a healthy group of people. The aim of screening is to find disease at an early stage to improve chances of treatment benefit and cure. A screening test gives us an indication of the likely presence of a disease. But further tests and investigations are usually required before we can reach a diagnosis.
In the case of the prostate there is a choice of three different screening tests.
First, there is the Digital Rectal Examination – the old DRE – where I put my finger into your anus and feel the prostate.
Second is the Prostatic Specific Antigen (PSA) blood test. PSA is a normal product of the prostate gland and but you do produce more of it when there's prostate cancer. At the same time, there are other reasons why you might have more PSA in your blood.
Finally, there's the Trans-Urethral Ultrasound (TRUS) where an ultrasound probe is introduced into the anus and the prostate is viewed on a television monitor.
Mick: You call that a choice.?
Doctor Bob: If you want to be screened then I usually recommend the finger up the bum and the blood test. Now screening for prostate cancer is controversial. Screening for every bloke is not recommended at this time because: i) the current tests are not good enough for screening; and ii) there is no clear evidence that it will increase life expectancy or quality of life. Also the screening tests are not very specific. This means that over two-thirds of men who have a positive test will be found not to actually have the disease after undergoing further intensive tests. On top of this, available screening tests cannot tell whether it will be an aggressive, quick-killing tumour or slow-growing and probably non-lethal. Also, some treatments may occasionally be worse than the disease itself.
Mick: Great, so I get to avoid your finger up my backside?
Doctor Bob: Well because you have a risk factor – your Dad – and a symptom – getting up a couple of times to pee in the night – we should check it. In your case, Mick, it's not really a screening test we should be looking at but I would like to check your urine.
Mick: I'm not too keen having your finger up my back passage. What does it involve and what are you looking for? And, by the way, have you cut your nails recently?
Doctor Bob: Firstly, let me reassure you I do have trimmed nails and quite a small index finger. The examination feels a bit like passing a stool. I get you to lie on your side with your pants half mast and knees drawn up to your chest. You take a couple of deep breaths through your mouth and I gently introduce my finger into your anus. I then turn my finger 180 degrees and feel your prostate. I am looking for size, smoothness and irregularities.
Mick: What if you find an abnormality?
Doctor Bob: Well, the thing we're most likely to find is an enlarged prostate. Thirty percent of men at your age would have an enlarged prostate but over 95% of these would be benign – what we call BPH or benign prostatic hyperplasia.
Mick: So what would be the treatment if it was a benign enlargement?
Doctor Bob: Well, there's a few choices between herbs, drugs and a surgical boreout. A herb called Serenoa repens has been claimed to help although its safety has not been well established. Then there are certain blood pressure tablets such as prazosin, terazosin and another new drug finasteride which is rather expensive. All these help widen the outlet pipe from the bladder. For mild peeing problems we usually just wait and see or use medication or herbs. In 20% of men the condition will get better by itself.
Mick: And the 'boreout'? I don't think I like the sound of that!
Doctor Bob: This involves a spinal or general anaesthetic and then an instrument is passed up the penis and literally chips out the core of the prostate. Occasionally, if the prostate enlargement is only mild only a small cut needs to be made in the prostate. Some new techniques include the use of a laser. This is called a laser prostatectomy.
Mick: OK, I think I get the picture. What about complications?
Doctor Bob: Generally the boreout is well tolerated and you are out of hospital after 4 days. However, it can lead to permanent complications such as retrograde ejaculation (where the sperm shoot into the bladder rather than come out the penis on ejaculation), impotence (failure of erection) and incontinence (wetting yourself).
Mick: And what if it was cancer?
Doctor Bob: As I said this is only found in 5% of enlarged prostates. The treatment depends on how far advanced the tumor has got. If the cancer has spread out into the pelvis or abdomen, then I'm afraid it is usually incurable. If, however, the tumor is confined to the prostate the treatment is either a radiotherapy, a radical prostatectomy where they remove the cancer via a wound in the lower abdomen or a boreout. Occasionally hormone therapy is used either by adding medication or surgically removing the balls.
Mick: Like how they knacker sheep? How could that possibly help?
Doctor Bob: Well, in removing the testes the aim is to reduce the level of testosterone in the body. Most prostate cancers need testosterone to grow. So by removing testosterone from the body the cancer shrinks.
Mick: How do you know which cancers need to be treated?
Doctor Bob: It is often difficult to predict which cancers need treatment. Many cancers are slow growing and may never affect nor kill the patient. So for some men we use 'watchful waiting' where we do regular checks, usually the PSA blood test rather than rush in with surgery.
Mick: So you've mentioned benign prostate enlargement & cancer what about the third thing – prostatitis?
Doctor Bob: This is where the prostate gets inflamed either from a germ or for no specific reason. The symptoms usually occur in younger men and may include painful and frequent urination, dull groin ache, muscle aches and fever.
Mick: Is there a treatment?
Doctor Bob: Sure. A simple antibiotic usually fixes the problem.
Mick: That's a relief. Well doc, thanks for taking the time to explain it all to me. It's good to be properly informed about prostate screening so I can make the decision about what's best for me ...so, I suppose I'd better drop my strides, let you run your finger over my prostate and see how the little bugger is....
Images reproduced with permission from Merck, Sharp and Dohme and Oxford Clinical Communications.
If you would like to ask Nick a question about your prostate or anything else medical you can do so by visiting his Special Adviser's area by clicking on Special Advisers in the menu bar below. |