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Why does your hair fall out when you have cancer?

Asked by: Alexis Garbarino
School: Maine Endwell Middle School
Grade: 7
Teacher: Roberta Rittenhouse
Hobbies/Interests: Swimming, Soccer and Piano
Career Interest: Pediatrician

Answer from Mary Muscari

Associate Professor, Binghamton University

Research area:
Youth violence, parenting.
PhD school:
Adelphi University.
Lots of fur babies!
Writing, pet rescue and gardening.

Cancer is such a common illness that most of us know someone - family member, neighbor or friend - who has or had it. There are many troubling issues a person faces when they have cancer, and hair loss may be one of them. Cancer is a group of diseases that develop when abnormal body cells grow very quickly. These cells can invade nearby body organs and spread through the blood and lymphatic fluid to other parts of the body. For example, leukemia is a cancer that starts in the blood-making tissues, such as the bone marrow, and causes large numbers of abnormal white blood cells to be made and enter the bloodstream. The rapid growth of cancerous cells causes health cells to die and the person with cancer to get sick. Some cancers are treated with radiation therapy (also called radiotherapy), which uses high doses of radiation to kill cancer cells and stop them from spreading. This is the same type of radiation that is used in x-rays, like the ones you get if you break a bone. But in cancer treatment, the doses of radiation are much higher. Radiation therapy is usually used directly over the area where the cancer is located. The skin covering that area may become reddened, and the hair may fall out. This hair loss may be temporary or permanent. Another treatment for cancer is a group of medicines commonly called 'chemotherapy' (key-mow-ther-uh-pee). The word chemotherapy actually means the use of any drug to treat any illness, but most people use the word to mean anticancer medications, which are also called antineoplastic (anticancer) therapy and cytotoxic (cell-killing) therapy. There are numerous types of chemotherapy drugs, but most act in a similar fashion. Chemotherapy kills fast growing cancer cells and, unfortunately, it may also kill other fast growing cells in the human body, including the ones in hair roots. People usually have to take their chemotherapy for weeks or months. The hair starts to fall out about two weeks after the person with cancer starts taking their chemotherapy. Hair may fall out a little at a time, or it may all fall out very quickly. Some people become completely bald, and some people lose their eye lashes, eye brows and body hair. The hair loss from chemotherapy is temporary. It usually starts to grow back about six weeks after the person finishes their chemotherapy, and it may look and feel different from the person's original hair. It may be curlier or a slightly different color. Sometimes hair grows in grey until the person's hair color (also called pigment) cells begin to work again. Most people will have a full head of hair again about six months to a year after they stop taking chemotherapy. Even though hair loss is temporary, it can be very upsetting. Therefore, it helps for people to plan ahead if they are going to get chemotherapy. People can get wigs that look like their real hair. They can also get hats or scarves. A lot of children who lose their hair to chemotherapy become hat collectors, getting caps from different major league baseball teams or different police departments. Health care professionals help find wig programs, hats and scarves, and they also help people with chemotherapy hair loss deal with their feelings. A little preparation can go a long way to help someone who loses their hair from chemotherapy.

Last Updated: 3/1/17