Medical Matters: Prostate cancer is a disease at a medical crossroads. Key questions continue to be debated. Should all men be screened, whether or not they show symptoms? What is the best treatment for early prostate cancers? Is it reasonable to adopt a policy of watchful waiting? Prostate cancer is the sixth commonest cancer around the world.
It is the most common cancer in Europe and North America. And although its incidence is rising steadily, we know little about what causes the disease.
Here, a new treatment option has become available. In March last year, Dr Michael Maher, director of radiotherapy at the Mater Private Hospital in Dublin, started to offer brachytherapy to patients with early-stage prostate cancer. He and his team are the only centre in the Republic to offer the treatment. Brachytherapy involves implanting radioactive seeds in the prostate gland. Brachy comes from the Greek for near or close - a reference to the placing of radiation close to the cancer rather than by the more usual route of external beam irradiation.
The prostate gland lies just below the bladder, at the point where the urethra collects the urine before carrying it through the penis. Unlike a benign enlargement of the prostate, which causes symptoms by squeezing the urethral tube, prostate cancer often remains within one area of the gland, causing few initial symptoms. By feeling your rectum, however, your doctor may detect a cragginess or lumpiness in the prostate gland. Combined with a blood test that measures prostate-specific antigen, the check can help to detect prostate cancer early.
Treating early-stage cancer traditionally involved choosing between a radical prostatectomy, in which a surgeon removed the entire gland, or radiotherapy given from outside the body. Brachytherapy now offers a third option. It is a two-stage procedure. The first, which involves a two-day hospital stay, is called the volume study. Carried out under general anaesthetic, it involves a detailed examination of the prostate using an ultrasound probe placed in the rectum. Images are transferred to a scanning computer, where a picture of the gland is reconstructed by Dr Michelle McNicholas, consultant radiologist at the hospital. The patient is discharged the next morning.
During a two- to three-week interval, Dr Maher and the medical-physics team at the Mater Private calculate the dose of radiation and ideal location of the seeds within the prostate gland. The patient is then admitted for a further two days. Again under anaesthetic, he is put in exactly the same position as before, so the iodine seeds - which lose half their radioactivity in two months - can be injected using an image from the first admission. Once he urinates successfully, he can go home.
There is a 10-15 per cent risk of developing an inflammation of the urethra, which means the patient will need a urinary catheter for four to six weeks, until the problem settles. For most patients, who do not need catheters, passing water may be painful for a time. They may also have to urinate more often than usual. Feeling sore for two or three days is also common. But probably a key statistic is that fewer than 1 per cent of men who choose brachytherapy go on to have problems with incontinence or sexual function.
So how have patients fared with the new treatment? As one might expect, there have been a range of experiences.Dr Maher describes a case from either end of the spectrum. A farmer from the south-east was admitted on a Tuesday, had brachytherapy the following day and was back home on Thursday. Despite being advised to take things easy for a few days, he felt well enough to cut 300 acres of corn the following weekend. A retired administrator from Dublin had a more difficult time. He developed acute urinary retention - a sudden, painful inability to pass water - 10 days after brachytherapy. An attempt to remove his urinary catheter after three weeks failed. It took a further three weeks for him to pass water spontaneously, although he is now well.
Brachytherapy is therefore not ideal for every patient with early-stage prostate cancer. Nor is the procedure available in the public health system. But as Dr Maher, who has now used brachytherapy on 34 men, says: "I think it is an ideal treatment for patients in their 60s and 70s with low-volume prostate cancer."
• You can e-mail Dr Muiris Houston at mhouston@irish-times.ie. He regrets he cannot answer individual queries