Chemotherapy circulates throughout your body in the bloodstream. So it can treat cancer cells almost anywhere in the body. This is known as systemic treatment. Nội dung chính Chemotherapy kills cells that are in the process of splitting into 2 new cells. Body tissues are made of billions of individual cells. Once we are fully grown, most of the body's cells don't divide and multiply much. They only divide if they need to repair damage. When cells divide, they split into 2 identical new cells. So where there was 1 cell, there are now 2. Then these divide to make 4, then 8 and so on. In cancer, the cells keep on dividing until there is a mass of cells. This mass of cells becomes a lump, called a tumour. Because cancer cells divide much more often than most normal cells, chemotherapy is much more likely to kill them. Some drugs kill dividing cells by damaging the part of the cell's control centre that makes it divide. Other drugs interrupt the chemical processes involved in cell division. The effects on dividing cellsChemotherapy damages cells as they divide. In the centre of each living cell is a dark blob, called the nucleus. The nucleus is the control centre of the cell. It contains chromosomes, which are made up of genes. These genes have to be copied exactly each time a cell divides into 2 to make new cells. Chemotherapy damages the genes inside the nucleus of cells. Some drugs damage cells at the point of splitting. Some damage the cells while they're making copies of all their genes before they split. Chemotherapy is much less likely to damage cells that are at rest, such as most normal cells. You might have a combination of different chemotherapy drugs. This will include drugs that damage cells at different stages in the process of cell division. This means there's more chance of killing more cells. Why chemotherapy causes side effectsThe fact that chemotherapy drugs kill dividing cells helps to explain why chemotherapy causes side effects. It affects healthy body tissues where the cells are constantly growing and dividing, such as:
Because these tissues have dividing cells, chemotherapy can damage them. But normal cells can replace or repair the healthy cells that are damaged by chemotherapy. So the damage to healthy cells doesn't usually last. Most side effects disappear once your treatment is over. Some side effects such as sickness or diarrhoea might only happen during the days you are actually having the drugs. How you have chemotherapyYou can have chemotherapy as:
Chemotherapy drugs that you have in these ways circulate all around the body in the bloodstream. They can reach cancer cells almost anywhere in the body. This is known as systemic treatment. How well chemotherapy worksThe chance of the chemotherapy curing your cancer depends on the type of cancer you have.
Examples of cancers where chemotherapy works very well are testicular cancer and Hodgkin lymphoma. With some cancers, chemotherapy can't cure the cancer on its own. But it can help in combination with other types of treatment. For example, many people with breast or bowel cancer have chemotherapy after surgery to help lower the risk of the cancer coming back. With some cancers, if a cure is unlikely, your doctor may still suggest chemotherapy to:
What remission meansRemission is a word doctors often use when talking about cancer. It means that after treatment there is no sign of the cancer. You might hear your doctor talk about complete remission and partial remission. Complete remissionThis means that the cancer can't be detected on scans, x-rays, blood tests or other tests. Doctors sometimes call this a complete response or they might say there is no evidence of disease. Partial remissionThis means the treatment has killed some of the cells, but not all. The cancer has shrunk, but can still be seen on scans and doesn't appear to be growing. The treatment might have stopped the cancer from growing. Or the treatment could have made the cancer smaller so that other treatments are more likely to help, such as surgery or radiotherapy. This is sometimes called a partial response. Another term doctors use is stable disease. This can mean that the cancer has stayed the same size or it might even have grown by a small amount. Which of the following best explains how treatment with a drug that stimulates the production?What explains how treatment with a drug that stimulates the production of insulin receptors on target cells will affect insulin signaling pathway in an individual with type 1 diabetes? The drug will have little to no effect on the signaling pathway because the receptors will not be activated in the absence of insulin. Which of the following best describes the effect of a drug that blocks the production of the mitotic?Based on the model of eukaryotic cell cycle regulation shown in the figure, which of the following best describes the effect of a drug that blocks the production of the mitotic cyclin? The cell would be prevented from entering mitosis, and the cell would stop dividing. Which of the following is the best explanation for the fact that the transduction step of cell signaling has multiple steps?Which of the following is the best explanation for the fact that most transduction pathways have multiple steps? Multiple steps provide for greater possible amplification of a signal. Which of the following best describes the role of growth factors in cell division quizlet?Which of the following statements best describes how a growth factor stimulates cell division from outside a cell? The growth factor binds to receptors on the cell surface, initiating a signal transduction pathway that activates specific target genes. Cancer can result from a variety of different mutational events. |