Evaluation of a Cone-beam CT Scanner for Image Guided Radiotherapy

This study will examine the image quality generated by a new cone-beam CT (CBCT) imaging system integrated into an external beam radiation treatment delivery platform. Normally, CBCT images are acquired at the start of a daily radiation delivery treatment to align the patient with the images that were used to generate their radiation treatment plan. This alignment increases the precision of radiation delivery. This study will assess whether the improvements in image quality expected from the novel CBCT imaging system are sufficient for the images to be used for more than just patient alignment. The study will enroll patients who will be treated with external beam radiation therapy for the following conditions: head and neck cancers, stage I lung cancer, stage II to IV lung cancer, cancer in the left breast, tumors in the abdomen, and tumors in the pelvic region. Each patient will undergo one additional imaging session with the novel CBCT imaging system during which 1 or 2 CBCT images will be acquired. The number of novel CBCT images acquired depends on the location and type of the patient's tumor. The additional imaging session will occur on the same day as one of the patient's scheduled treatment delivery sessions to minimize impact on the patient's schedule. The patient's cancer treatment will not be affected by participation in this study. The methodology for the subject's treatment setup, CT simulation, treatment planning, image guidance and treatment delivery will be determined by the subject's treatment team. The images acquired by the novel CBCT imaging system will be compared to standard CBCT images acquired as part of the patient's treatment and to the CT simulation images used to define the patient's radiation treatment plan.