When is hormone treatment used?
This is not a simple question to answer, for many factors need to be considered prior to choosing this treatment option. In general, hormonal therapy is used when there is evidence that the cancer is no longer confined to the prostate (and sometimes to shrink the gland prior to removal or radiotherapy).
Commonly hormone treatment is used for men in whom radical treatments have not succeeded in curing the disease, ie following radical surgery or radiotherapy. Often our best indicator of recurrent prostate cancer growth is from a rising PSA level (PSA is a blood test which, after surgery or radiotherapy, indicates the amount of cancer activity still remaining in the body - see information sheets 2 and 4). The exact timing of hormone treatment in response to a rising PSA level is variable and based to some extent on the speed of tumour growth and the sites of the tumour.
Hormone treatment is also the principal therapy for metastatic prostate cancer when the prostate cancer cells have escaped from the prostate to grow in other sites of the body. In this case, the treatment may be started soon after this diagnosis is made, although on occasions a delay in starting does not pose serious risk to the patient.
Hormone therapy may also be used to shrink the tumour prior to or in conjunction with other treatments. There is some evidence that it may be beneficial when used with radiotherapy, however, its use in conjunction with surgery is controversial (if proposed, this should be discussed with a specialist). Once the prostate treatment has been completed, the hormone treatment is usually stopped and the response observed, by following the PSA levels.
What does hormone treatment involve?
Essentially, there are two ways of reducing male hormones:
* By surgery where the testicles are removed (orchidectomy)
* By medication, either in the form of regular injections or tablets. Both are effective. (Refer to Table 1 and Figure 1).
Since the testicles provide over 95% of the male hormones it is obvious that their removal will reduce the levels. This occurs very quickly after the operation, which is performed sometimes as day surgery but more commonly with an overnight stay in hospital. An advantage of this form of hormone treatment is that the inconvenience and cost of regular medications is avoided.
Medications are available as an alternative to orchidectomy. The injectable drugs act on the brain to reduce the production of male hormones in the testicles and currently last from 1- 3 months per injection. This means that regular monthly or 3-monthly injections are required to control the cancer cell growth, and should these be stopped, the prostate cells will begin to grow.
Tablets are available to control the cancer cells also, although they are not frequently recommended by themselves as a first choice method of cancer control. In the past, both injectables and tablets were frequently used in combination to control prostate cancer cell growth (called total androgen ablation). However, we are currently not certain of the additional effectiveness of taking a tablet whilst on an injectable drug or in combination with orchidectomy (removal of the testicles). Sometimes hormone therapy may be given in cycles ie started and stopped repeatedly.
This type of treatment is called intermittent hormonal therapy. Typically, hormone treatment is continued for several months until PSA has reached a low level, and then discontinued. Once the PSA level in blood rises to a particular level again (and this can take many months), hormone therapy is started again. The benefits of this approach are a reduction in side effects (see the next section), and potentially prolonging the effectiveness of hormone therapy (although we are not yet sure that this is the case).
What are the current medications available in Australia?
A list of current medications available in Australia is shown in Table 1.
What are the side effects of hormone treatment?
Many of the side effects of hormone treatment are related to the lack of normal levels of male hormone within your body and occur whether you choose surgery or medications. These are summarised in table 2 below. Typically, most men suffer from poor or absent erections (impotence) and there is also a lack of interest in sexual activity (reduced libido). Your voice will not change; however, some men notice an alteration of their body hair, such that it is a different texture and may grow again on previously quite bald areas. Tiredness is a common complaint, and is related to the main male fuel being suppressed.
Hot flushes are very common in the early stages of treatment but may decline spontaneously after several months of treatment. There are medications available to reduce the intensity of this sometimes disabling symptom if required. Over many months or years there may be a decline in muscle strength and some tenderness or enlargement in the breast area.
Before commencing on hormonal therapy, it is helpful to discuss the possibility of side effects with your wife or partner. Good communication is important in dealing successfully with these changes and maintaining your close relationship.
A word about hormonal therapy
The very nature of this treatment, the removal of male hormone or its effects means that a man will experience changes in the way he feels, his attitudes, and of course his sex life. While this can be distressing, and it means communication with your partner is particularly important, it does not change who you are. It does not change your identity as a man and your ability to direct your own life. Some men feel a need for a change in focus in their lives at this stage, however, and they may take up activities which are more meaningful to them. According to these men, the years that follow can be rewarding and productive.
Hormone resistance: what if the treatment stops working?
The ability of hormone treatment to control your cancer is quite variable. Some men (approximately one in five) have recurrent growth within a year from starting hormone treatment whereas others have no sign of recurrent disease after 10 years of treatment. The average time to PSA evidence of regrowth (hormone resistance) is 2.5 years. The delivery of hormone therapy in bursts (ie intermittent rather than continuous) as a way of delaying the onset of resistance is possible with medications, but not after the removal of the testicles with an operation. Whilst this approach has some theoretical advantages, its benefits have not yet been established, and continuous hormonal therapy is still regarded by most doctors as the best option.
When resistance to hormonal therapy occurs (usually indicated by rising PSA in the blood), treatment is frequently tailored to an individual’s symptoms. Symptoms typically occur many months to years after evidence of cancer regrowth and are related either to growth of the cancer in the pelvic region (blood in the urine, reduced ability to pass urine) or growth at distant sites such as the bones (pain in the pelvis, back, etc).
Treatment Options for Hormone-resistant Cancer:
Options available for this stage of the disease are:
(1) Radiotherapy, to alleviate pain and control cancer growth at sites away from the prostate. Radiation is usually delivered by ‘external beam’ (meaning from outside the body) in this setting although agents which are injected are sometimes used.
(2) Additional hormone treatments, typically tablets. Not many men have a lasting favourable effect from “second-line” hormonal therapy; however, a downward trend to the PSA can occur for some months. Stopping one tablet and using a different one is also sometimes helpful.
(3) Steroids such as prednisolone to control pain and reduce tumour growth.
(4) Non-specific pain relief medications, including arthritis-type tablets and morphine.
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