Find answers below to the questions we hear most often, such as what radiation therapy involves and what ASTRO does. For more information, visit RT Answers for brochures, videos and other patient-friendly information, or contact ASTRO's media relations team.
The American Society for Radiation Oncology (ASTRO) is the largest radiation oncology society in the world, with more than 10,000 members who specialize in treating patients with radiation therapies. As the leading organization in radiation oncology, biology and physics, ASTRO is dedicated to improving patient care through education, clinical practice, advancement of science and advocacy. Read more about ASTRO's history.
ASTRO’s members are physicians, nurses, biologists, physicists, radiation therapists, dosimetrists and other health providers and scientists who specialize in treating patients with radiation therapies. ASTRO’s membership consists of health care professionals from community medical centers as well as academic research facilities. Read more about ASTRO member demographics.
Within the field of radiation oncology, ASTRO promotes scientific and technological advancements by sponsoring meetings for oncologists and other health care providers, publishing three peer-reviewed research journals, and providing educational and professional development opportunities for its members.
Within the medical community, ASTRO fosters cooperative efforts between radiation oncologists, medical oncologists, surgeons and other physicians to provide effective treatment through a team approach.
ASTRO also publishes educational materials to keep patients and the general public informed about radiation therapy as a treatment option. ASTRO also works with the media to promote accurate articles on scientific breakthroughs involving radiation therapies and is a major contributor in the development of legislation and regulations affecting patient care.
Radiation therapy, also called radiotherapy or irradiation, is the careful, therapeutic use of high-energy waves or streams of particles called radiation. At low doses, physicians and radiologists use radiation for diagnostic purposes to take internal pictures (X-rays) of the body. Radiation oncologists, highly trained cancer treatment specialists, use higher doses of radiation to treat cancer and other diseases. Patients benefit from this type of treatment because the high-energy waves used in radiation therapy are able to kill fast-growing cancer cells while minimizing damage to healthy tissue.
A specially trained physician, called a radiation oncologist, is responsible for prescribing a patient’s radiation therapy treatment. The radiation oncologist works with a specially trained team of health care professionals, including radiation oncology nurses, medical physicists, dosimetrists and radiation therapists. This team works under the direction of the radiation oncologists to ensure high quality care for patients. Radiation oncologists are different from radiologists, who use radiation to diagnose disease and detect other health problems.
Depending on the location of the cancer, patients can receive radiation therapy either externally or internally. External radiation is created and delivered by special machines, typically linear accelerators. With external radiation, a machine directs the high-energy waves at the cancer and a small amount of the healthy tissue surrounding it. When internal radiation is used, the radiation source is placed inside the body. The radiation source can be delivered by an intravenous injection or by temporarily or permanently inserting radioactive pellets or wires directly into the tumor. The insertion of a radioactive substance into a tumor is called brachytherapy.
With external radiation, the total dose of radiation needed to kill the cancer cells is more than most patients can handle at one time so the dose is typically spread out over a series of daily outpatient treatments. Each treatment is brief and the radiation therapy machine will turn on and off throughout the treatment. The actual treatment is painless, but there can be side effects depending on what part of the body is being treated. The total number of treatments varies with the type of cancer and the extent of disease and can range from one to forty treatments. With internal radiation, some brachytherapy treatments are given more than once depending on the type and the extent of the patient’s cancer. Some types of brachytherapy are given on an outpatient basis while others require admission to a hospital for one or more days.
The radiation oncology team is made up of radiation oncologists, radiation oncology nurses, medical physicists, dosimetrists, radiation therapists and social workers. All states require continuing medical education for these professionals, and many states have programs to regularly inspect the radiation therapy equipment.
To become a radiation oncologist, you must complete four years of college, four years of medical school, one year of general medical training and four years of residency or specialty training in radiation oncology. In order to become board-certified in radiation oncology, you must pass a series of exams administered by the American Board of Radiology.
ASTRO’s Annual Meeting is the nation’s leading scientific meeting about advances in radiation oncology.
These meetings highlight the best and most up-to-date research in radiation oncology. Meetings also provide ASTRO members and other attendees with education and professional development opportunities, including continuing medical education (CME) credits for physicians, continuing education units for nurses and medical dosimetrists, and CAMPEP credits for physicists.
The Annual Meeting is held concurrently with annual gatherings of the American Society of Radiologic Technologists (ASTR) and the Society of Radiation Oncology Administrators (SROA).
ASTRO’s 64th Annual Meeting will be held October 1-4, 2023 at the San Diego Convention Center in San Diego. The theme of the meeting is “Pay it Forward: Partnering with our Patients.” Learn more about the upcoming Annual Meeting.
The ASTRO Annual Meeting attracts thousands of attendees including oncologists from all disciplines, medical physicists, dosimetrists, residents, radiation therapists, radiation oncology nurses and nurse practitioners, biologists, physician assistants, practice administrators, industry representatives and other health care professionals from around the world.
ASTRO Annual Meetings also include a press program, with news briefings that highlight a select group of top-rated studies from the meeting. View a recap of the most recent press program, including recordings and photos from the news briefings.
Cancer is the second leading cause of death among all Americans, exceeded only by heart disease. According to the American Cancer Society, approximately 606,520 Americans are expected to die of cancer in 2020 - roughly 1,660 people a day.
The death rate from cancer, however, dropped 29% from its peak in 1991 to 2017 (the most current data available), due mainly to reductions in smoking, as well as improvements in early detection and treatment.
More than 1.8 million new cancer cases will be diagnosed in 2020. Over the course of a lifetime, approximately 40 out of 100 men and 39 out of 100 women will develop cancer. About 80% of all cancers are diagnosed in patients aged 55 or older. More than 16.9 million U.S. adults and children with a history of cancer were alive on January 1, 2019, according to the American Association for Cancer Research, and the number of cancer survivors is projected to rise to 22.1 million by January 1, 2030.
The five-year relative survival rate for all cancers is 70%, which means that 70% of all patients diagnosed with cancer survive for five years or longer, and 30% live fewer than five years. The five-year relative survival rate has increased from 49% in the late 1970s, following advances in treatment, screening and diagnosis.
Skin cancer is the most commonly diagnosed cancer in the United States. The next most common cancer for men is prostate cancer, followed by lung cancer and colorectal cancer. The next most common cancer for women is breast cancer, followed by lung cancer and colorectal cancer. Among children age 14 and younger, the most common cancers are leukemias.
Approximately $80.2 billion was spent on cancer-related health care in the U.S. in 2015, the most current data available. This total includes costs paid by employers, insurance companies, public programs like Medicare and Medicaid, patients with cancer and their caregivers — including nearly $4 billion spent by patients out-of-pocket for cancer treatment.
Content last updated 1/15/2020.