In simple words: Special X-ray pictures, called port films, are taken during radiation treatment to make sure the radiation is aimed correctly at the tumor.

Therapeutic radiology port films are X-ray images, typically taken by a radiation therapist, of the treatment area.The provider uses these films to show the precise shape, size, and area covered by the treatment beam during radiation therapy, ensuring accurate positioning.

Example 1: A patient undergoing external beam radiation therapy for lung cancer. Port films are taken weekly to verify beam placement and adjust for any tumor movement or changes in anatomy., A patient receiving intensity-modulated radiation therapy (IMRT) for prostate cancer. Port films are acquired after each fraction to ensure the radiation beam conforms precisely to the target area., A patient with head and neck cancer undergoing image-guided radiation therapy (IGRT). Port films are used in conjunction with other imaging modalities (CT or MRI) to confirm accurate target localization and to correct for any patient motion.

* Physician's order specifying the need for port films.* Documentation of the date and time of each port film acquisition.* Indication of the treatment fraction number.* Identification of the specific port(s) imaged.* Clear correlation between the port films and the treatment plan.

** This code describes the technical component of obtaining port films only.Any professional component related to interpretation and medical decision making should be reported separately using appropriate E/M codes.