Hormone therapy for prostate cancer
What is hormone therapy for prostate cancer?
With hormone therapy for prostate cancer, the androgen dependence of prostate cancer is used for therapeutic purposes. Androgens such as Testosterone, are male sex hormones that are produced in the testes and, to a small extent, in the adrenal gland. Among other things, they lead to the growth and multiplication of prostate cancer cells.
Hormone therapy is more precisely a hormone withdrawal therapy in which the growth stimulus for the tumor cells is reduced by suppressing the release of hormones. Hormone therapy is also known as chemical castration, as it has the same effect as castration by surgical removal of both testicles. Various active ingredients are used for hormone therapy that intervene at different points in the process of androgen release.
Read more on the subject at: Prostate cancer
Who is hormone therapy suitable for?
The therapy of prostate cancer is divided into curative, i.e. healing, therapy options and palliative, i.e. soothing, therapy options.
Radical prostate removal is part of curative therapy (Prostatectomy) with lymph node removal, which can be supplemented with radiation if necessary. Alternatively, irradiation can take place from the outside. These two treatment options are equivalent.
The hormone therapy is carried out both curative and palliative. As part of curative therapy, hormone therapy is used in addition to external radiation. It can help improve the outcome of radiation treatment for prostate cancer.
If a decision is made against curative therapy or if distant metastases are present, hormone therapy is used as part of a palliative therapy concept. As an alternative to hormone therapy, the concept of watchful waiting can be pursued as part of a palliative approach. This means that the progression of the tumor is only observed until symptoms appear.
Read more on the subject at: Treatment of prostate cancer
Which hormones are used?
Strictly speaking, no hormones are used. Medicines are used that act like certain hormones.
The regular release of testosterone works in the following ways. In part of the diencephalon (Hypothalamus) the luteinizing hormone releasing hormone (LH-RH or GnRH) is released. This leads to the pituitary gland (Pituitary gland) for the release of luteinizing hormone (LH). The LH in turn leads to the production of the androgen testosterone in the testes. The testosterone slows down the release of LH through a feedback mechanism.
The drugs for hormone therapy in prostate cancer are divided into different groups depending on where they act. These are:
direct testosterone synthesis inhibitors
A combination of several drugs from different groups is also possible.
The drugs for hormone therapy can be given in the form of intermittent or continuous treatment. With continuous treatment, patients receive the medication permanently. In intermittent treatment, the therapy is carried out until a control value (PSA value) falls below a specified lower limit. Therapy is now paused until the control value exceeds the upper limit again. The advantage of intermittent treatment is, on the one hand, the rarer occurrence of side effects and a longer treatment duration until castration resistance occurs.
LH-RH analogs, also called LH-RH agonists, act like LH-RH itself. They lead to the release of LH in the pituitary gland. This in turn leads to an increase in testosterone production in the testes. This initial surge in testosterone is known as the flare-up phenomenon. The sustained stimulation reduces the number of receptors for LH-RH on the pituitary gland and leads to an insensitivity to the LH-RH. As a result, the testosterone level also drops and the tumor cells lose their growth stimulus.
LH-RH analogs are used in the form of depot injections into the muscle or under the skin.
LH-RH antagonists act opposite to LH-RH. They block the receptor for LH-RH on the pituitary gland. As a result, less LH is released and fewer androgens are produced in the testes. The growth of prostate cancer cells is slowed down.
In contrast to the LH-RH analogues, the LH-RH antagonists do not initially have increased testosterone concentrations.
LH-RH antagonists are also given as a depot syringe.
Antiandrogens, also known as androgen receptor antagonists, have a similar structure to androgens themselves. They can block the androgen receptors on prostate cancer cells and thus prevent the hormone from working locally. Antiandrogens also to a small extent inhibit the release of LH from the pituitary gland and consequently also lower the release of testosterone.
They are often used in combination with LH-RH analogues. The combination is called complete androgen block. This is particularly helpful at the beginning of therapy in order to reduce the initial rise in androgen in LH-RH analogues
Antiandrogens are taken as tablets. Newer substances in this group of active ingredients are still effective even after the tumor has become castration-resistant, i.e. the hormone therapy has no effect.
What are the side effects of hormone therapy?
The side effects of hormone therapy for prostate cancer can be summarized under the term androgen withdrawal syndrome. They can be explained by the lack of effect of testosterone.
The side effects include:
Hot flashes and sweats
Loss of libido
Mammary gland enlargement (Gynecomastia)
Metabolic changes with a higher risk of diabetes mellitus and heart disease
Osteoporosis with an increased risk of fractures
Due to the wide range of side effects, the patient should be informed in detail about these side effects before starting hormone therapy and informed about alternative treatment options.
Colorectal cancer risk from hormone therapy
A study published in 2010 showed that hormone therapy for prostate cancer increased the risk of colon cancer in the examined patients by 30-40%. The study also showed that the longer the hormone therapy was on, the greater the risk.
What successes can be expected with hormone therapy?
If hormone therapy is used in prostate cancer as a complement to curative therapy, the goal is to increase the effectiveness of the radiation.
In the context of palliative therapy, the main goal is to use hormone therapy to delay the progression of the disease and the growth of the tumor. Furthermore, complications can be prevented by means of hormone therapy and symptoms caused by metastases can be alleviated.
What are the costs of hormone therapy?
There is no specific information about the cost of hormone therapy for prostate cancer. Whether the costs of such therapy are covered by health insurance varies depending on the health insurance.
What are the alternatives to hormone therapy?
An alternative to hormone therapy is surgical removal of both testicles (castration). The surgery also causes decreased testosterone production as the main testosterone production site is removed. However, removal of the testicles is very rarely done.
In the context of palliative therapy, the concept of “watchful waiting” is an alternative to hormone therapy. This means that the progression of the tumor can only be monitored through regular check-ups until symptoms appear. These complaints are then treated symptomatically. The advantage of this therapy is that the side effects of hormone therapy can be avoided and, in the best case, the quality of life is preserved. However, there may be a misunderstanding of the threat posed by cancer.
What is the life expectancy under hormone therapy?
If the hormone therapy is carried out as part of a curative therapy, prostate cancer is still curable. However, if the tumor has already spread and formed distant metastases, it is no longer considered curable. In this case, hormone therapy is carried out as palliative therapy. Life expectancy varies depending on how malignant the tumor is and where the metastases are. Despite distant metastases, life expectancy can be several years.
Read more on the subject at: Life expectancy in prostate cancer
Duration of hormone therapy
Hormone therapy for prostate cancer should be continued for as long as it is effective. In most cases, after about two years, the tumor develops resistance to the medication and the therapy is no longer effective. The tumor can continue to grow despite very low testosterone levels. Prostate cancer is called castration-resistant at this stage. There is now the option of treatment with newer substances from the class of antiandrogens or chemotherapy, which are still effective even in the case of resistance.