Patients treated with intensity-modulated radiation therapy (IMRT) for cervical or endometrial cancer have fewer adverse events and experience better quality of life than those treated with conventional radiation therapy (RT), according to research presented at the 2016 American Society for Radiation Oncology (ASTRO) Annual Meeting (September 25-28; Boston, MA).
Radiation therapy following surgery to remove cervical or endometrial tumors is fairly common, but questions remain about which method best eliminates tumors while minimizing the impact of radiation on surrounding healthy tissue. IMRT, an advanced form of external beam RT that delivers precise radiation doses highly tailored to patients’ individual tumors, has been proposed as an alternative to conventional four-field RT capable of improving patient outcomes with less toxicity.
In the study presented at ASTRO, researchers compared these two techniques by evaluating patient-reported acute toxicities in the gastrointestinal (GI) and genitourinary (GU) systems following IMRT or standard four-field RT.
A total of 278 patients with cervical or endometrial cancer who received post-operative pelvic RT were included in the study and randomly assigned to receive either IMRT or standard RT. Acute GI and GU toxicities were measured via multiple patient questionnaires.
Overall, patients in the IMRT arm of the study experienced significantly fewer bowel-related toxicities than patients who received standard RT. They also reported fewer high-level adverse events following treatment, including less diarrhea (33.7% vs 51.9%) and fecal incontinence (1.1% vs. 9.3%). Additionally, 20.4% of women in the RT group reported taking 4 or more anti-diarrheal medications daily while only 7.8% of women did the same in the IMRT group.
Further, patients in the IMRT group also experienced fewer urinary side effects than those who were treated with RT, as evidenced by a significant decline in average Expanded Prostate Cancer Index Composite scores for the IMRT arm (-5.6 vs. -10.4). IMRT also had less of an impact on patients’ quality of life and resulted in less of a change in physical well-being compared with conventional RT.
“Many radiation oncologists already use IMRT for women undergoing pelvic radiation, but this research provides data that using IMRT, which is a more resource intensive treatment, makes a real difference to patients receiving radiation therapy to the pelvic area,” said Ann H Klopp, MD, PhD, lead author of the study and an associate professor in the department of radiation oncology at the University of Texas MD Anderson Cancer Center in Houston. “When performed by an experienced radiation oncology team, IMRT reduces the risk of short-term bowel and bladder side effects for patients with endometrial and cervical cancer.”
