Over the course of a 4-5 week treatment the investigators know that some patients may lose weight, some become more relaxed after a few days, and some have trouble with the movement in their shoulders; all of these factors influence the positioning of the patient. Measurements taken on the treatment unit often change during the course of a patient's treatment, but no further verification is performed to ensure that the treated area is still what was initially intended. It is important from a quality assurance standpoint to see if more frequent checking of the radiation treatment set-up is indicated.