In laypersons' terms, chemotherapy is the use of drugs to treat cancer. More precisely, however, differentiations are made between anti-cancer medications such as chemotherapy, immunotherapy and antihormone therapy.
Chemotherapeutic substances are drugs which interfere in the metabolism of the cancerous cells. They inhibit the growth of the cancer cells or kill them off. Therefore, they are also known as cytostatic drugs. Over time, more than 100 different cytostatics have been developed which can be used for different cancers.
Artificial antibodies are administered during immunotherapy for cancer patients. These either stimulate the immune system directly or bind themselves to the cancer cells, thus supporting the immune cells in their fight against the cancer cells. By marking the cancer cells with the antibody, the immune system recognises the cancer cells and can destroy them.
Antihormone therapy combats hormones which encourage the growth of cancer cells in the body. It is used, for example, in patients with breast cancer or prostate cancer. The medication inhibits the hormone completely or prevents it having any effect on the cancer cells.
What preparations are carried out before the procedure?
Before suitable medical cancer treatment can be found, examinations must be undertaken to determine the type and function of the cancer cells. For example, in the case of breast cancer, examinations are done to see whether the growth of the cancer cells is stimulated by oestrogen, which would make subsequent antihormone treatment sensible.
Different examinations such as MRI, computer tomography or skeletal scintigraphy are used to clarify whether further metastases have already formed in the body. The stage of the cancer has a significant bearing on the treatment chosen. Cancer treatment requires collaboration between specialists from different fields. It is planned to the letter in interdisciplinary teams known as tumour boards.
How is the procedure performed?
Medical cancer treatment must usually be performed consistently over a long time or in several cycles. Depending on the type of cancer, lifelong treatment is required. The cancer drug must often be injected or administered over an infusion. However, there are also many medications which exist in tablet or capsule form.
Chemotherapy with medication which directly kills the cancer cells or inhibits their growth is used in many different types of cancer. Certain types of cancer such as leukaemia or lymphoma are primarily treated with chemotherapeutics. In the case of other cancers such as lung cancer, breast cancer or bowel cancer, chemotherapy is used after an operation or irradiation. In such cases, this is referred to adjuvant chemotherapy. Chemotherapeutics can cause nausea and vomiting. This is why a medicine against nausea is often administered at the same time as chemotherapy.
Immunotherapy, antibody therapy
Immunotherapy or antibody therapy sets artificially created antibodies against the cancer. These bind themselves with structures on the surface of the cancer cells, and are known as receptors. As a result, the characteristics of the cancer cells change. It dies or is better recognised by the immune system of the body and destroyed. With the immunotherapy, major progress has been made in the treatment of cancers. It is used in the case of certain types of breast cancer, which show HER2 receptors on their surface. Another example are tyrosine kinase inhibitors, which are used on different types of leukaemia such as chronic myeloid leukaemia (CML).
Certain types of cancer such as breast cancer, cancer of the uterus or prostate cancer react to hormones. Their growth is promoted through sex hormones such as oestrogen or testosterone. In the case of breast cancer and uterine cancer, therefore, clarification is always made of whether they show cancer hormone receptors. If this is the case, the antioestrogen hormone therapy is initiated. In the process, either the production of oestrogen in the body is inhibited or medications are used which inhibit the effect of oestrogen on the cancer cells.
In the case of prostate cancer, no hormone receptor measurement must be undertaken. The growth of this type of cancer is at the beginning also dependent on the hormones. Antihormone treatment consists of the suppression of the male sexual hormone (androgens, testosterone). This antiandrogenous treatment is primarily used in patients with prostate cancer which can no longer be healed with surgery.
The medications are administered in different forms: in the form of tablets which must be taken on a daily basis or in a deposit which is injected in larger intervals under the skin or implanted.
What is the success rate of this procedure?
The treatment success during drug-related treatment of cancer is dependent of various factors. The aggression of the cancer and the degree of spread play a decisive role in the process. Many types of cancer can be well treated with chemotherapy, immunotherapy or antihormone therapy over the long term, or sometimes even cured. However, the growth of other cancers can only be suppressed for a certain period of time.
What are the possible complications and risks of this procedure?
Cancer drugs are medications which have a major effect on the body. This is necessary to successfully treat the cancer. Despite the progressively more targeted medications, the treatment is usually not without side effects. Chemotherapeutics work primarily on cells which divide quickly, i.e. mucous membrane cells in the digestive tract, hair roots and blood cells. Typical side effects are the corresponding hair loss, digestive disorders, nausea, increased risk of infection and clotting disorders.
Antihormone therapy can lead to menopause-like symptoms. It can also impact on the sexual function of men.
The effectiveness of drug-related cancer treatment must always be weighed up against the possible side effects.
What happens after the treatment?
Regular checks are required to monitor how the disease is progressing and whether the treatment has been successful. The length of the drug-related treatment is dependent on the situation and the type of cancer. Sometimes drugs must be adjusted or the dosage changed.