What is cancer cells

The doctor will talk with the person about his or her medical history and symptoms. Then the doctor will do various tests to find out the cause of these symptoms. But many people with cancer have no symptoms. For these people, cancer is diagnosed during a medical test for another issue or condition. Sometimes a doctor finds cancer after a screening test in an otherwise healthy person.

Examples of screening tests include colonoscopy , mammography , and a Pap test. A person may need more tests to confirm or disprove the result of the screening test. For most cancers, a biopsy is the only way to make a definite diagnosis. A biopsy is the removal of a small amount of tissue for further study. Learn more about making a diagnosis after a biopsy. Request Permissions. What is Cancer? Approved by the Cancer. How cancer begins Cells are the basic units that make up the human body.

Types of cancer Doctors divide cancer into types based on where it begins. Four main types of cancer are: Carcinomas. There are as many types of cancer cells as there are types of cancer. Of the hundred-plus types of cancer, most are named for the type of cancer cells in which it began.

Carcinomas are cancers that arise in epithelial cells that line bodily cavities. Sarcomas are cancers that arise in mesenchymal cells in bones, muscles, blood vessels, and other tissues. Leukemias, lymphomas, and myeloma are "blood-related cancers" that are arise from the bone marrow leukemias and multiple myelomas or the lymphoid tissues lymphomas and "fed" by nutrients in the bloodstream and lymph fluid such that they don't need to form tumors.

Just as cancers may behave differently from one another, not all cancer cells behave the same way. Cancer cells appear through a series of genetic and epigenetic changes. Some of these changes may be either inherited or more often, caused by carcinogens cancer-causing substances in our environment.

In general, solid tumors, contain multiple mutations. Interestingly, the metastatic process that is the main culprit for the high mortality of advanced cancers is thought to be caused mostly by epigenetic changes as no specific genetic alterations have been found in metastases.

It also helps explain a genetic predisposition to cancer. A genetic predisposition does not mean you will get cancer, but, simplistically, if a few mutations are already in place, it will likely take fewer acquired mutations for a cell to become cancerous. The process of normal cells becoming cancer often goes through stages in which the cell becomes progressively more abnormal appearing. These stages may include hyperplasia, dysplasia, and finally cancer.

You may also hear this described as differentiation. Early on a cell may look much like normal cells of that organ or tissue, but as progression occurs, the cell becomes increasingly undifferentiated. This is, in fact, why sometimes the original source of cancer cannot be determined.

A cancer cell can have thousands of mutations, but only a certain number of these genetic changes in cancer cells cause cancer to divide and grow. Tumor suppressor genes , in contrast, are genes within the cell which tell cells to slow down and stop growing, repair damaged DNA, or tell cells when to die.

Most cancer cells have mutations in both oncogenes and tumor suppressor genes which lead to their behavior. There are many important differences between cancer cells and normal cells. Some of these include:. The ability to invade and metastasize is very important in differentiating a cancer cell from a normal healthy cell, but there are many other important distinctions as well.

Cancer cells remain alive either by evading detection they disguise themselves in different ways or by inactivating the immune cells that come to the scene. The ability of the immune system to recognize and eliminate cancer cells is thought to be responsible for the uncommon but well-documented phenomena of some cancers going away without treatment of the spontaneous remission of cancer.

This process also lies at the crux of the new field of cancer treatment known as immunotherapy. Once a cancer has formed, the cells don't remain the same, but rather continued mutations may occur. This, in fact, is why resistance develops to chemotherapy and targeted therapy drugs in time.

The cancer cell develops a mutation that allows it to bypass the damaging effects of these treatments. That cancer cells change is very important in treatment. For example, a breast cancer that is estrogen-receptor positive may be estrogen-receptor negative when it recurs or spreads. It also helps explain whey cancer cells in different parts of a tumor may be different.

This is referred to as "heterogenicity" and is important in diagnosis and treatment as well. Precancerous cells may look abnormal and similar to cancer cells but are distinguished from cancer cells by their behavior. Normally, our cells follow these instructions and we stay healthy.

But when there is a change in our DNA or damage to it, a gene can mutate. This can cause cells that should be resting to divide and grow out of control, which can lead to cancer. But cancer cells are different. Cancer cells have gene mutations that turn the cell from a normal cell into a cancer cell.

These gene mutations may be inherited, develop over time as we get older and genes wear out, or develop if we are around something that damages our genes, like cigarette smoke, alcohol or ultraviolet UV radiation from the sun. It starts to grow and divide out of control instead of dying when it should.

Although there are many different types of cancer, they all start because of cells that are growing abnormally and out of control. Cancer can start in any cell in the body. But as a tumour grows, it needs more blood to bring oxygen and other nutrients to the cancer cells. So cancer cells send signals for a tumour to make new blood vessels. This is called angiogenesis and it is one of the reasons that tumours grow and get bigger. It also allows cancer cells to get into the blood and spread more easily to other parts of the body.

There is a lot of research that is looking at using drugs that stop blood vessel growth called angiogenesis inhibitors , causing a tumour to stop growing and even shrink.

Cancer can also spread from where it first started to other parts of the body. Genomic tumor assessment may result in a more personalized approach to cancer treatment. Chat live now or call us Make a difference in the fight against cancer by donating to cancer research. Call us anytime. What is cancer? What are the most common forms of cancer?

There are five main categories of cancer: Carcinomas begin in the skin or tissues that line the internal organs. Sarcomas develop in the bone, cartilage, fat, muscle or other connective tissues.

Leukemia begins in the blood and bone marrow. Lymphomas start in the immune system. Central nervous system cancers develop in the brain and spinal cord. How is cancer treated?