Recent initiatives for radiation oncology resident education in radiation and cancer biology.

Nearly all residents from accredited radiation oncology residency programs in the United States are required to take the American College of Radiology (ACR) In-Training examination each year. The test is comprised of three sections: Clinical Radiation Oncology, Radiological Physics, and Radiation (and Cancer) Biology. Here we provide an update on changes to the biology portion of the ACR exam. We also discuss the availability and use of the ACR and biology practice exams as assessment and teaching tools for both the instructors of radiation and cancer biology and the residents they teach.