How Cancer Grows and Spreads
Cancer is a disease in which cells grow out of control and form a mass or lump called a tumor. These abnormal cells can also break away from the tumor and travel through the blood or lymph system to other parts of the body. These new cancer cells can then start growing and forming more tumors, which is called metastasis. There are over 100 different types of cancer. Some are more serious than others.
Normally, cells are programmed to grow and die in a controlled way. But sometimes, a mutation in one or more genes causes them to develop out of control. As these cells divide, they can acquire additional mutations that make them more malignant. Over time, the number of mutations can lead to a mass of abnormal cells that is cancer.
Genetic changes that cause cancer can happen by chance, or they may be inherited from parents. They can also result from exposure to certain chemicals or radiation. Most often, cancer-causing genetic changes accumulate slowly over a person’s lifetime. These gene changes can affect three main types of genes-proto-oncogenes, tumor suppressor genes, and DNA repair genes. These genes help control cell growth and regulate how quickly the cell divides.
Cancer can be classified according to its size and whether it has spread from where it started to other parts of the body. The stage of the cancer is a key factor in choosing the best treatment. A lower stage means the cancer is smaller and hasn’t spread very much. A higher stage means the cancer is bigger and has spread further.
Understanding how cancer grows and spreads can help doctors find better ways to treat it. The goal is to stop the cancer from developing in the first place, or at least detect it early and treat it before it has a chance to spread.
A new molecular view of cancer gives clues about how to accomplish this. Cancer development is viewed as a process of evolution by natural selection, in which the cancer cell is the unit of selection. This model helps explain why cancer is a multistep disease, rather than a single massive shift in cellular functions caused by one or two wayward genes.
During this process, heritable variation in cell traits arises through random mutations and the struggle for existence among competing cells drives the evolution of some cells toward a lethal phenotype. These evolutionary principles are well established in cancer research, even if they are rarely invoked explicitly. The current state of knowledge about the mechanisms of cancer initiation and progression allows us to view this as an evolutionary process, and to target prevention, detection, and treatment efforts specifically at the genes that drive it. This is the future of cancer medicine.
Cancer is a disease in which cells grow out of control and form a mass or lump called a tumor. These abnormal cells can also break away from the tumor and travel through the blood or lymph system to other parts of the body. These new cancer cells can then start growing and forming more tumors, which is called metastasis. There are over 100 different types of cancer. Some are more serious than others. Normally, cells are programmed to grow and die in a controlled way. But sometimes, a mutation in one or more genes causes them to develop out of control. As these cells divide, they can acquire additional mutations that make them more malignant. Over time, the number of mutations can lead to a mass of abnormal cells that is cancer. Genetic changes that cause cancer can happen by chance, or they may be inherited from parents. They can also result from exposure to certain chemicals or radiation. Most often, cancer-causing genetic changes accumulate slowly over a person’s lifetime. These gene changes can affect three main types of genes-proto-oncogenes, tumor suppressor genes, and DNA repair genes. These genes help control cell growth and regulate how quickly the cell divides. Cancer can be classified according to its size and whether it has spread from where it started to other parts of the body. The stage of the cancer is a key factor in choosing the best treatment. A lower stage means the cancer is smaller and hasn’t spread very much. A higher stage means the cancer is bigger and has spread further. Understanding how cancer grows and spreads can help doctors find better ways to treat it. The goal is to stop the cancer from developing in the first place, or at least detect it early and treat it before it has a chance to spread. A new molecular view of cancer gives clues about how to accomplish this. Cancer development is viewed as a process of evolution by natural selection, in which the cancer cell is the unit of selection. This model helps explain why cancer is a multistep disease, rather than a single massive shift in cellular functions caused by one or two wayward genes. During this process, heritable variation in cell traits arises through random mutations and the struggle for existence among competing cells drives the evolution of some cells toward a lethal phenotype. These evolutionary principles are well established in cancer research, even if they are rarely invoked explicitly. The current state of knowledge about the mechanisms of cancer initiation and progression allows us to view this as an evolutionary process, and to target prevention, detection, and treatment efforts specifically at the genes that drive it. This is the future of cancer medicine.