What is the primary purpose of a bolus in radiation therapy?

The primary purpose of a bolus in radiation therapy is to modify the beam. Bolus materials are used to bring the radiation dose closer to the surface of the patient’s skin, which helps to ensure that the prescribed dose covers the tumor effectively. By doing this, bolus can compensate for tissue inhomogeneities and create a more uniform dose distribution in areas that might not receive adequate radiation if the beam were applied without an additional layer of material. This becomes particularly important in treating superficial tumors, as it allows for better targeting of cancer cells while minimizing exposure to surrounding healthy tissues.

In this context, while comfort, enhancing dosage, and stabilizing equipment might be considerations in a clinical setting, they do not represent the primary function of a bolus in radiation treatments. The bolus's specific role is to modify how the radiation is delivered to optimize treatment effectiveness.