SAN DIEGO – Endorectal balloons appeared to protect against rectal complications from prostate cancer radiation in a small randomized trial from Australia.
The balloons have been around for years, but the Australian study is likely the first randomized trial of long-term clinical outcomes. The balloons are inserted and inflated during radiation treatments, which in the study were daily for 6-7 weeks. They distend the rectum, reducing radiation exposure, and also stabilize the prostate. The investigators used the RectalPro balloon from Qlrad.
M. Alexander Otto/Frontline Medical News
Rochelle Botten
The 40 men were all undergoing image-guided radiation therapy; 20 got the balloon, 20 did not. At 2 years, four balloon patients (25%) had rectal bleeding, versus 10 (50%) of the controls (P less than .001). Balloon patients also had fewer bowel symptoms, less rectal hypersensitivity, and less reduction in internal anal sphincter thickness. Three (15%), versus six controls (30%), reported declines in physical function from their preradiation baseline, and one balloon patient (5%), versus three controls (15%) reported declines in role functioning (P less than .05 for both).
Rectal pain, however, was more common with the balloon at 2 years (six patients [30%] versus two [10%], P less than .001), and balloon patients had reduced anal squeeze pressures (P less than .05). They also reported a higher prevalence of urinary symptoms.
Further follow-up is needed to determine if benefits outweigh risks; if they do, then the balloon “will become standard procedure in our hospital,” said investigator Rochelle Botten, a research scientist in the department of radiation oncology at the Royal Adelaide Hospital.
Given the study’s small numbers, it’s unclear if urinary problems – for instance, incontinence, pain, frequency – are truly associated with the balloon, but it’s “something we’ve got to look at. We are going to study” the men “again at 3 years to see if they’ve resolved, and we’ll have more patients for 2-year follow-up. If we are pressing everything towards the bladder, it [could make] sense that the bladder is getting more radiation.
“We are hoping as the numbers increase, we’ll be able to look at how much of the bladder and how much of the rectum are actually irradiated, and if there’s a difference with the balloon,” she said at the annual Digestive Disease Week meeting.
Ms. Botten had no disclosures.