True or False: Photon beams have a finite range in a patient.

Photon beams, such as those used in radiation therapy, indeed have a finite range within a patient. This is due to the fundamental interactions between photons and matter, primarily through processes like photoelectric absorption, Compton scattering, and pair production. As the photon beam travels through tissue, it loses energy and ultimately becomes ineffective at delivering therapeutic doses beyond a certain depth, depending on the energy of the photons.

In essence, as these photons penetrate the body, they gradually get absorbed or scattered, which limits their effectiveness and ultimately reduces the dose that can be delivered at deeper tissues. Therefore, the correct statement that accurately reflects the behavior of photon beams is that they do indeed have a finite range in a patient. The assertion that the answer is "False" does not accurately represent the physics involved. Understanding this property of photon beams is essential for effective treatment planning in radiation therapy, ensuring that the target area receives an adequate dose while sparing surrounding healthy tissues as much as possible.