RapidArc™ yields shorter treatment times and lower dosage to surrounding areas in Verity patients.

RapidArc™ radiotherapy technology, a major advance from Varian Medical Systems, is setting new standards in treatment for Verity patients. By shortening treatment times by as much as 8 times faster than current dynamic treatments, patients are not uncomfortable as long and radiotherapy can be more effectively delivered to organs prone to frequent movement such as the prostate. Furthermore, RapidArc means lower dosages to healthy surrounding areas of the body including vital organs.

Instead of treating tumors from many different angles, as with conventional IMRT (Intensity Modulated Radiation Therapy), RapidArc treatment is given in one continuous arc. The shape of the treatment field and amount of dose changes to conform to the tumor volume while avoiding critical nearby body areas.

Lung Case Study: Less dosage to nearby organs greatly benefits lung cancer patient.

A female lung cancer patient in her 90s had a large tumor in her right lung, located very close to her heart. Treatment needed to avoid the spinal cord and her healthy lung. Additionally the patient was extremely uncomfortable, and had trouble breathing as well as constant pain. She was barely able to tolerate the traditional course of treatment, which lasted for 5½ minutes per session.

RapidArc treatments to the lung lasted only 75 seconds compared to 5½ minutes with conventional IMRT treatments. The same dose of radiation (as previously given) was delivered to the tumor area, but the patient’s comfort was improved because she only had to stay still for a shorter period of time. More importantly, the doses received by the surrounding structures were much lower with RapidArc. The spinal cord dose was reduced by 30% and the dose to the healthy lung were lowered by almost 50%. The overall dose to the heart was also reduced significantly.

Prostate Study: Reduced treatment time keeps moving organ in target field.

When Verity installed RapidArc, the 56-year-old prostate cancer patient was switched to from conventional IMRT radiotherapy to this more advanced method of treatment. The same dose was delivered to the prostate as with IMRT treatments, but the dose to such surrounding organs as the bladder and rectum was equal to or lower than that with IMRT.

On each day of treatment with RapidArc, there was a 4-minute savings in treatment time –down from 5½ minutes to 1½ minutes each day—and a significant savings in treatment time over the entire course of radiation therapy. Since the prostate typically is in constant motion (studies have shown that the longer the treatment lasts, the more the prostate moves), this faster delivery made a huge difference: the prostate did not have a chance to move out of the target treatment field. Overall patient comfort was also improved with the shorter treatment time.

Head & Neck Study: RapidArc brings significant relief to nasopharynx cancer patient.

Nasopharynx cancer—involving the head and neck—is especially uncomfortable to treat because the patient must wear an aquaplast mask that is both claustrophobic and tight fitting in order to keep the area still. A male patient (65 years old) had his treatment shortened from 9 minutes, 25 seconds each day with conventional IMRT therapy to just 3 minutes, 3 seconds per session using RapidArc. The patient suffered much less discomfort with RapidArc since he only had to wear the mask and be still for one-third of the time.

The primary dose was to the nasopharynx and neighboring lymph nodes. The dose to the adjacent parotid gland was decreased by 30%. One side effect of irradiation to the parotid is dry mouth; less dosage to this area minimized this discomfort. Both brain stem and spinal cord doses were lower, as were doses to other normal tissues nearby.