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Our 24/7 cancer helpline provides support for people dealing with cancer. We can connect you with trained cancer information specialists who will answer questions about a cancer diagnosis and provide guidance and a compassionate ear.
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At our National Cancer Information Center trained Cancer Information Specialists can answer questions 24 hours a day, every day of the year to empower you with accurate, up-to-date information to help you make educated health decisions. We connect patients, caregivers, and family members with valuable services and resources.
Or ask us how you can get involved and support the fight against cancer. Some of the topics we can assist with include:
For medical questions, we encourage you to review our information with your doctor.
You cannot “catch” cancer from someone else. Close contact or things like sex, kissing, touching, sharing meals, or breathing the same air cannot spread cancer. Cancer cells from someone with cancer are not able to live in the body of another healthy person. The immune system finds and destroys foreign cells, including cancer cells from another person.
Although cancer is not contagious, there are some situations that can make people think that cancer has spread from one person to another.
Although cancer itself is not contagious, there are some germs that can play a role in the development of certain types of cancer. This may lead some people to wrongly think that “cancer is catching.” Infections that have been linked to cancer include viruses, bacteria and parasites.
If cancer were contagious, we would have cancer outbreaks just as we do with the flu. We would expect a high rate of cancer among the families and friends of people with cancer and among health professionals who care for them. This is not the case.
The fact that cancer might happen more often in certain families does not mean that the family members have spread cancer to each other. Reasons for this include:
Some people point to “clusters” of cancer patients who have had contact with each other as proof that cancer is contagious. But clusters almost never reflect a higher rate of cancer than in the general public. In rare cases where there is more cancer in a group, it’s hard to know what other factors, such as exposure to cancer-causing agents and lifestyle, might be responsible for the cancer cluster.
In very rare cases, cancer cells from an organ donor have caused cancer to grow in the person who got the organ. This does not happen often, because our immune systems look for cells that are not our own and destroys them. However, people who get organ transplants must take medicines to weaken their immune systems so their body doesn't attack and destroy the transplanted organ. Organ donors are carefully screened for cancer to reduce this risk.
Still, recent studies have shown that cancer is more common in people who get organ transplants. This is likely because of the drugs given to reduce the risk of organ rejection, rather than cancer spreading from the donated organ. Because these drugs weaken the immune system, they can prevent the body from finding and attacking damaged cells and viruses that can lead to cancer.
Even if a woman has cancer during pregnancy, the cancer rarely affects the baby. Some cancers can spread from the mother to the placenta (the organ that connects the mother to the baby), but most cancers cannot affect the baby itself.
Even today, families, friends, and co-workers will sometimes stay away from a loved one with cancer. This can make the person with cancer feel isolated and alone. But you cannot “catch” cancer from them. Don’t be afraid reach out to the person with cancer. They need your visits and support.
The American Cancer Society medical and editorial content team
Our team is made up of doctors and oncology certified nurses with deep knowledge of cancer care as well as journalists, editors, and translators with extensive experience in medical writing.
Acuna SA. Etiology of increased cancer incidence after solid organ transplantation. Transplant Rev (Orlando). 2018 Oct;32(4):218-224.
Centers for Disease Control and Prevention. About Cancer Clusters. Cdc.gov; 2019. Accessed at https://www.cdc.gov/nceh/clusters/about.htm on March 3, 2021.
Greaves M, Hughes W. Cancer cell transmission via the placenta. Evol Med Public Health. 2018 Apr 14;2018(1):106-115
National Cancer Institute. Common Cancer Myths and Misconceptions. Cancer.gov. Updated August 22, 2018. Accessed at https://www.cancer.gov/about-cancer/causes-prevention/risk/myths on March 3, 2021.
Last Revised: March 4, 2021
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