Inclusion Criteria:

• * Subjects will be treated with external beam radiotherapy at the Perelman Center for Advanced Medicine for any of the following malignancies: head-and-neck, thoracic, breast, gastrointestinal, gynecologic, or genitourinary.
• * Age ≥ 18 years
• * Ability to understand the requirements of the study and to give written informed consent, as determined by the treating physician
• * Availability of a complete set of treatment plans, including CT simulation images, target and normal structure contours, and radiation treatment prescriptions

Exclusion Criteria:

• * Subjects who are pregnant or have plans for pregnancy during the period of treatment.
• * Any malignancy not stated above.
• * Those unable to be treated on any linear accelerator (whether Truebeam™ or Halcyon™) unit either due to subject anatomy or treatment plan.
• * Those undergoing proton therapy.