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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.
Cancer of unknown primary (CUP) represents a number of different cancers, so there is no known way to prevent it. Still, certain lifestyle changes may reduce the risk of many types of cancer. This might in turn reduce a person’s risk of CUP.
Smoking is one of the most significant risk factors that a person can control, and is thought to be directly related to deaths from cancer. Quitting or never starting reduces the risk of cancers of many types, including those of unknown primary. Please call us if you need help quitting tobacco. This, and a lot more information about tobacco, can be read online or mailed to you.
Factors linked with body weight, physical activity, and eating patterns are also known to affect the risk for different types of cancers and deaths related to cancer. Staying at a healthy weight throughout life, being physically active, following a healthy eating pattern, and limiting alcohol intake can all help reduce your risk of cancer.
Because the exact type and the origin of a CUP are unknown, it’s not possible to say how any particular case might have been prevented. It is important to realize that many people with cancer have no apparent risk factors, and there’s nothing they could have done to avoid the disease.
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.
Greco FA, Hainsworth JD. Carcinoma of Unknown Primary In: DeVita VT, Lawrence TS, Rosenberg SA, eds. DeVita, Hellman, and Rosenberg’s Cancer: Principles and Practice of Oncology. 10th ed. Philadelphia, PA: Lippincott Williams & Wilkins 2015: 1719-1736.
Hemminki K, Chen B, Melander O, Manjer J, Hallmans G, Hemminki A. Smoking and body mass index as risk factors for subtypes of cancer of unknown primary. Int J Cancer. 2015 Jan 1;136(1):246-7. doi: 10.1002/ijc.28969.
Rock CL, Thomson C, Gansler T, et al. American Cancer Society guideline for diet and physical activity for cancer prevention. CA: A Cancer Journal for Clinicians. 2020;70(4). doi:10.3322/caac.21591. Accessed at https://onlinelibrary.wiley.com/doi/full/10.3322/caac.21591 on June 9, 2020.
Søndergaard D, Nielsen S, Pedersen CNS, Besenbacher S. Prediction of primary tumors in cancers of unknown primary. J Integr Bioinform. 2017 Jul;14(2):pii. doi: 10.1515/jib-2017-0013.
Varadhachary GR, Lenzi R, Raber MN, Abbruzzese JL. Carcinoma of Unknown Primary In: Neiderhuber JE, Armitage JO, Doroshow JH, Kastan MB, Tepper JE, eds. Abeloff’s Clinical Oncology. 5th ed. Philadelphia, PA. Elsevier: 2014:1792-1803.
Last Revised: June 9, 2020
American Cancer Society medical information is copyrighted material. For reprint requests, please see our Content Usage Policy.