Every year around 22,000 men in New Zealand and Australia develop prostate cancer. It is the most common cancer diagnosis in many developed countries. It is the result of abnormal cells in the prostate multiplying when they shouldn’t, causing a lump or tumour. These cancerous cells can grow throughout the prostate and through the capsule surrounding the prostate. They can spread to sites well away from the prostate, such as the bones and lymph nodes, known as a metastases or secondaries.
Prostate cancer is usually slowly growing, although some are more aggressive. Either way, as men are living longer and prostate cancer can cause many unpleasant problems and even death, treatment is often recommended to ‘cure’ the disease before it spreads outside the prostate.
If cancer travels away from the prostate region it can appear in bones and other organs. Although some treatment is likely still helpful, long term ‘cure’ is no longer possible. Therefore, early detection and careful monitoring and/or treatment are important for many men who have prostate cancer.
What Are the Causes of Prostate Cancer?
The exact cause is not known, however some factors are known to increase the risk. Only men have a prostate gland (beneath the bladder) meaning that women can not get prostate cancer.
Prostate cancer is rare before the age of 40, with the risk increasing substantially after age 50.
A strong family history of prostate cancer is associated with an increased risk, particularly in those with specific genetic conditions which are also associated with breast and ovarian cancer in women (BRCA mutations). The influence of diet on the risk of prostate cancer is unclear, however large amounts of red meat and dairy are thought by some to be associated with prostate cancer.
There are some variations between race and incidence of prostate cancer – Caucasian and African-American men have a higher risk than Asian men for example.
What Are the Symptoms of Prostate Cancer?
Most men with prostate cancer do not have symptoms. Importantly, prostate symptoms do not usually signify prostate cancer. However as the cancer grows, changes in urination are more common. Symptoms of prostate cancer may include
- increased trips to the toilet,
- difficulty starting or stopping,
- urinary dribbling or a slow flow of urine may be symptoms of prostate cancer.
In more aggressive disease, difficulty gaining an erection, pain or blood with ejaculation, and pelvic pain can occur. When prostate cancer is detected after it has spread, then bone pain is a common consequence.
What Are the Treatments for Prostate Cancer?
Treatments aimed at curing prostate cancer include external beam radiation therapy (EBRT or radiotherapy), brachytherapy, and surgery. The most suitable treatment will depend on many factors to do with the patient and the cancer, and often there are choices for the patient about which treatment he would prefer.
The patient should be helped to make a decision after discussions with the specialists who manage prostate cancers. The relevant specialists are the urologist (surgeon) who usually makes the diagnosis using biopsies, and the radiation oncologist.
External Beam Radiation Therapy is often performed using Intensity-Modulated Radiation Therapy (IMRT), a modern, technology allowing high doses of precisely targeted radiation to be delivered to the prostate using x-rays, with minimal impact on the surrounding tissues.
The most modern approach of IMRT utilises Image-Guided Radiation Therapy to image the prostate for each treatment to ensure millimetre accuracy. External Beam Radiation Therapy is usually delivered once a day, Monday to Friday, over a number of weeks (usually 7 – 9 weeks), the treatment itself taking around 10 minutes per day.
The treatment uses x-rays so patients are not radioactive after treatment. The benefits of External Beam Radiation Therapy include the ability to treat prostate cancer that has invaded locally outside the capsule surrounding the prostate, or into tissues around the prostate, which is not possible to cure with surgery alone. It involves no stay in hospital or recovery from an operation.
Radiation therapy is often combined with 6-24 months of hormone treatment, shown in scientific studies to increase the treatment cure rates for some prostate cancers. All prostate cancers localised to within or just outside the prostate can be treated with radiation therapy. This is not the case with other treatment approaches, such as surgery (see below).
Prostate brachytherapy involves implanting radioactive ‘seeds’ or sources into the prostate, which deliver targeted radiation to kill cancer cells. The seeds can be implanted permanently, called Low Dose Rate Brachytherapy (LDR), or the sources inserted briefly using a special machine, then removed.
This is called High Dose Rate Brachytherapy (HDR) and is usually combined with a short course of External Beam Radiation Therapy and may be used for slightly more aggressive cancers.
Surgery to remove the entire prostate is called a radical prostatectomy, and can be performed with an incision in the lower abdomen, or assisted with cameras inserted through small holes in the abdomen (laparoscopy). Some centres perform robotic prostatectomies, which is a special type of laparoscopic procedure which involves the surgeon controlling surgical tools at a distance from the actual patient.
If the prostate cancer is seen to have extended beyond the prostate capsule after surgery, radiation therapy may be required to treat the prostate cancer left behind.
If cancer cells have travelled further outside the prostate (metastasised), it is still treatable, however long term ‘cure’ is not possible. Hormonal (ant-testosterone) treatment is often used to slow down or control the cancer. External Beam Radiation Therapy is very effective in treating any painful metastases, and is commonly used if the prostate cancer has spread to the bones.
Chemotherapy and other drug treatments can be used later in the course of prostate cancer treatment, especially after hormonal therapy becomes ineffective.
How Effective Is Radiation Therapy For Prostate Cancer?
All conventional options (surgery, radiation therapy or brachytherapy) offer the same chance of cure for the same cancer.
The effectiveness of ‘seed’ brachytherapy for suitable (early) prostate cancers is now accepted as being at least as good as radical prostatectomy with overall lower side effects, better quality of life and equal survival rates than surgery.
The effectiveness of external beam radiation therapy for prostate cancer appears to be at least as good as surgery, with recent dramatic improvements in modern radiation therapy techniques occurring as a result of innovative technology. These advances have allowed radiation therapy to be more accurately targeted to the site of cancer, reducing the chance of serious side effects and allowing higher doses of radiation to be delivered to the tumour.
In the case of prostate cancer, this ‘dose-escalation’ has led directly to more cancer cells being killed and higher cure rates compared to, say, 15-20 years ago. This is why it is very important that men have the option of talking to a radiation oncologist who is up-to-date with the modern technology about this management option.
What Are the Side Effects for Radiation Therapy?
Side effects during/soon after treatment (Early or ‘acute’ side effects)
General – Fatigue is quite common in the second half of treatment and is very variable between patients. It may be worse for men on hormone treatment as well having radiation therapy. This may persist for a few weeks after treatment but for most men, as for other early side effects, this has usually settled within 4 -6 weeks after radiation therapy is completed.
Local – All other side effects of radiation therapy come from the structures/organs in and just next to where the radiation is being targeted. For the prostate this means the bottom of the bladder, the urethra (the tube through the prostate where urine passes) and the front part of the rectum (lower bowel). These can commonly cause the following side effects, which usually have fully settled by 4- 6 weeks after treatment is finished.
Bladder/urethra – in weeks 3-4 of treatment it is common to start to get some or all of the following: increased frequency of urine, especially at night; stinging or burning while passing urine; a sense of not fully emptying the bladder; a poorer stream than before. These symptoms are usually mild to moderate but can be worse if there were significant urinary problems before treatment.
Rectum – it is common in the second half of treatment that the bowel motions may be a bit more frequent or there is a sense to needing to go more frequently or urgently to open the bowels though not much may be passed. There may be some more mucous production, excess wind and/or discomfort on opening bowels. Diarrhoea is very uncommon.
What can help reduce side effects?
Resting as needed can help with fatigue though some men find regular exercise helps as well. During treatment patients are given advice about their bowels and bladder and are encouraged to drink plenty of water especially in the earlier part of the day and to keep the motions soft and easy to pass. Over the counter medicines can help with stinging in the urine. If bowel symptoms are more severe, suppositories can prescribed by the doctor though this is quite unusual with modern radiation therapy. These side effects are rarely severe with modern targeted radiation therapy and commonly settle quickly after treatment.
Side effects well after treatment (Late or long-term side effects)
Late side effects may occur a few months or years after treatment though they are much more rare than early side effects. Depending on the problem these may occur once and then go or may be more persistent over the long term or may come and go over time.
Local side effects
Bladder/urethra – Incontinence is very rare after radiation therapy alone but is more common when combined with surgery. Tightening of the urethra with scarring (structuring) occurs in about 2-3% of men having radiation therapy alone. Bleeding from abnormal blood vessels in the bladder as a result of previous radiation therapy is not common but is seen in some cases, and needs to be investigated to exclude another more serious cause .e.g bladder cancer.
Rectal (lower bowel) changes from radiation therapy can cause (usually minor) change in bowel habit, excess mucous production, or bleeding in <10% of men (though this does not necessarily occur all the time). These symptoms are severe enough to impact significantly on long term quality of life < 5% of the time.
Sexual function (erections) can be reduced over time after radiation therapy (more so if men are on hormone treatments), especially if there was some decline before treatment. For men with ‘normal’ sexual function, erections are reduced over time in around half, although there may be many other factors that affect this. The ejaculate becomes less in amount and fertility is affected.
Second cancers occurring as a result of radiation therapy seem to be an extremely rare side effect of radiation therapy to the prostate.
What can be done to treat late side effects?
Bleeding from the bladder or rectum can be treated with techniques that use laser to close up bleeding blood vessels if this problem persists. This is especially effective for the rectum. Dietary measures can help if the bowels are more urgent or frequent over the longer term. Stretching of urethral strictures by a urologist can alleviate a worsening urine stream from this cause. Medical treatments can be used to improve erections after a discussion with doctor (tablets and/or penile injections).
The correct person to discuss radiation therapy treatment for prostate cancer is a Radiation Oncologist. You can ask your Urologist or General Practitioner for a referral to a Radiation Oncologist for a discussion about whether radiation therapy is a good option for you.
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Haines Ian. The scandal of prostate cancer management in Australia Medical Journal of Australia Issue 45, 21 November 2016
Hamdy FC, Donovan JL, et al. Prostate Testing for Cancer Treatment (ProtecT) Trial Study Group, 10-Year Outcomes after Monitoring, Surgery, or Radiotherapy for Localized Prostate Cancer. The New England Journal of Medicine, 14 September 2016
Prostate Cancer Treatment Options Cancer Institute NSW Fact Sheet, June 2016
Comparing Treatment Results Of Prostate Cancer- Prostate Cancer Results Study Group- Updated June 2015
LDR Brachytherapy: Latest Advances In Prostate Therapy Treatment- BJUI Supplements
What is brachytherapy and how effective is it for prostate cancer? Interview with A/Prof Jeremy Millar, Director, Radiation Oncology, Alfred Health
What are the indications for radiotheapy for distant metastatic diesase? Interview with A/Prof Jeremy Millar, Director of Radiation Oncology, Alfred Health
Donald Patterson was the 400th man to be treated with LDR brachytherapy. View his experience.
Radiation Therapy for Prostate Cancer, Targeting Cancer, April 2017