COVID-19 updates
Quality CareFind out why Mayo Clinic is the right place for your health care. Make an appointment.
Meet the StaffFind a directory of doctors and departments at all Mayo Clinic campuses. Visit now.
Research and Clinical TrialsSee how Mayo Clinic research and clinical trials advance the science of medicine and improve patient care. Explore now.
Visit Our SchoolsEducators at Mayo Clinic train tomorrow’s leaders to deliver compassionate, high-value, safe patient care. Choose a degree.
Professional ServicesExplore Mayo Clinic's many resources and see jobs available for medical professionals. Get updates.
Philanthropy at Mayo ClinicYour support accelerates powerful innovations in patient care, research and education. Give today.
Mayo Clinic offers appointments in Arizona, Florida and Minnesota and at Mayo Clinic Health System locations.
Subscribe to Housecall
Our general interest e-newsletter keeps you up to date on a wide variety of health topics.
To indicate the area where radiation should be aimed, your radiation therapy team uses a combination of laser lights and marks on your body. This also ensures that your body is precisely aligned and positioned properly for each treatment session.
What type of mark you receive depends on your cancer and your treatment. In certain cases, marks are drawn on your skin with a marker. You can wash these marks off once your final treatment is completed.
Mayo Clinic does not endorse companies or products. Advertising revenue supports our not-for-profit mission.
Check out these best-sellers and special offers on books and newsletters from Mayo Clinic.