Chemotherapy is a treatment used for certain types of cancer. In certain situations chemotherapy in lower doses is used to treat non-cancerous conditions. Chemotherapy uses anti-cancer drugs to destroy cancer cells like leukemia and lymphoma. The type of chemotherapy will depend on the type, spread and location of cancer. It may also be used in conjunction or in combination with other types of cancer treatments.
Chemotherapy drugs stop the division of cancer cells. Since it is administered through the blood stream, they can reach cancer cells anywhere in the body. Chemotherapy drugs can also affect some of the healthy cells in your body, which can cause unpleasant side effects. This damage is temporary and most side effects will disappear once the treatment is over.
Certain cells are more sensitive to chemotherapy drugs which include bone marrow, hair follicles, lining of mouth and digestive system. The treatment sessions are intermittent with period of rest in between which allows the normal cells and tissues to recover. Multiple cycles like this make up a course of treatment. With certain types of cancer, chemotherapy is likely to destroy all the cancer cells and cure the disease. Chemotherapy may also be given after surgery or radiotherapy to destroy any cancer cells that may remain. It also helps to shrink a cancer before another treatment such as surgery.Palliative chemotherapy is aimed at controlling and shrinking of cancer to prolong life.
Chemo prior to surgery known as neo-adjuvant or primary chemotherapy is aimed at reducing the size of a cancer that is too large-or too attached to surrounding healthy tissue. This can make removing the cancer easier during a later operation. Chemo given after a surgery known as adjuvant chemotherapy is aimed at removing any residual cancerous cells which are too small to be seen, and have been left behind. Chemotherapy may also be given if a cancer cannot be completely removed during an operation. In such cases the cancer may shrink and hence reduces symptoms.
Chemocan also be given at the same time as radiotherapy. In some types of cancer, high-dose chemotherapy is given. This is usually done after initial chemotherapy has got rid of the cancer cells but there is a high risk of the cancer coming back. High doses of chemotherapy would normally destroy the bone marrow-which makes the blood cells-so the bone marrow has to be replaced after the chemotherapy has been given. This is done using stem cells which have been collected from the bone marrow or blood. The stem cells are collected before the high-dose treatment, either from the patient, or from someone else (a donor) whose cells are a good match. They settle in the bone marrow and develop into the different blood cells.
Chemotherapy may be given in different ways, depending on the type of cancer you have and the chemotherapy drugs used.Most often chemotherapy is given by injection into a vein (intravenously) known as intravenous chemotherapy.
All the above methods are aimed at the drug entering the blood stream and traveling around the body to reach the cancer cells.
In intrathecal chemotherapy, the drugs are injected into the spinal fluid. When the drugs are injected into particular body cavities such as the pelvic cavity or bladder, it is known as intracavity chemotherapy. Drugs given in this way tend to stay in the area in which they are given and do not affect cells in other parts of the body. Chemotherapy creams may be used for some cancers of the skin: they only affect the cells in the area of skin to which the cream is applied. Sometimes, two or more types of chemotherapy may be used together; for example, intravenous and oral chemotherapy.Intravenous chemotherapy
There are four ways of giving chemotherapy drugs directly into the vein. These could be through a Cannula inserted into a vein in your arm or a Central line inserted through the skin of the chest into a vein near the heart, a PICC line (a peripherally inserted central catheter) in the bend or upper part of the arm and threaded through until the end of the tube lies in a vein near the heart, Implantable port (also called a portacath) that is put into a vein.
The cannula after insertion is secured by suitable tape to keep it in place. A bag of fluid is then attached to the cannula along with which the chemotherapy drugs are given.
When using a central line, a long, thin plastic tube is put into a vein in your chest after administering general or local anesthesia. Once in place, the central line is either stitched or secured suitably. A central line can stay in the vein for many months; utmost care has to be taken in maintaining sterility of the contact area. The line has to be flushed with a suitable sterile solution twice a week to prevent clotting.
In the case of a PICC line, you will be given a local anesthetic before the line is inserted. Once it is in place, the PICC line is taped firmly to your arm to prevent it being pulled out of the vein. Similar to the central line, a PICC line can also be maintained for months.Administering the drug.
There are different methods used in administering the drugs. Infusion pumps which give a controlled amount of drugs at a predetermined time may be used to give some types of chemotherapy. There portable pump comes in various sizes. Chemotherapy tablets or capsules can be taken at home as all or part of your treatment. Suitable advice on schedule will be given by the treating doctor. Oral chemotherapy can cause side effects and it is important to be aware of these when taking your medicine. Chemotherapy can be done Intramuscular (muscle of the leg or buttock) or as a Subcutaneous injection.Intrathecal chemotherapy
In some conditions such as leukemia or lymphoma (cancer which starts in the lymph system) cancer cells can pass into the fluid which surrounds the brain and spinal cord. This fluid is called cerebrospinal fluid. To prevent this from happening, or to treat it if it occurs, chemotherapy may be given into the cerebrospinal fluid. For this treatment you will usually need to lie on your side with your legs drawn up. The doctor will then use local anesthetic to numb an area of skin over your spine. A needle is inserted into the space between two of the spinal bones and into the cerebrospinal fluid and the chemotherapy is injected. This procedure is called a lumbar puncture.
It takes from 15 to 30 minutes and you may need to lie flat afterwards for a few hours. It is important to drink plenty of fluids to reduce the chance of getting a headache. If you get a headache, it may last for a few hours. Painkillers can be given to help. Chemotherapy given in this way does not usually cause any other side effects.Intracavity chemotherapy
To give chemotherapy drugs in this way, a tube is inserted into the affected body cavity, for example the bladder (intravesical treatment) or the abdominal area (intraperitoneal treatment). The chemotherapy is put in through the tube. It may then be drained out again after a set period of time. Drugs given in this way may cause some irritation or inflammation in the area they are given, but they do not tend to cause side effects in other parts of the body.The treatment schedule and type will depend upon a number of factors including the type, spread and location of the cancer. Before each cycle of chemotherapy, routine blood tests will be done to assess the patient. Regular checks will be done to understand the treatment response and effects on the other parts of the body. After chemotherapy you will have to undergo regular check-ups and possibly scans or x-rays. These will probably continue for several years.