This study was designed to determine whether oral retinol palmitate (vitamin A) can reduce the symptoms of radiation proctopathy.
Dr Ehrenpreis and colleagues from Chicago, America conducted a randomized, double-blind trial comparing retinol palmitate (10,000 IU by mouth for 90 days) to placebo.
The investigators enrolled patients with more than 6 months postpelvic radiotherapy that had symptoms as measured with the Radiation Proctopathy System Assessments Scale (n=19).
|Symptoms were measured with the Radiation Proctopathy System Assessments Scale|
|Diseases of the Colon & Rectum|
The research team randomised 10 to retinol palmitate and 9 to placebo.
Radiation Proctopathy System Assessments Scale scores before and every 30 days for 90 days were measured by the researchers.
The team crossed over 5 placebo nonresponders to the retinol palmitate for another 90 days.
The researchers defined response as a reduction in 2 or more symptoms by at least 2 Radiation Proctopathy System Assessments Scale points.
7 of 10 retinol palmitate patients responded, whereas 2 of 9 responded to placebo.
The research team noted that the mean pre-post-treatment change in Radiation Proctopathy System Assessments Scale in the retinol palmitate group was 11, and 2.5 in the placebo group.
In addition, the researchers observed that all 5 placebo nonresponders who were crossed over to treatment with retinal palmitate responded to treatment.
Dr Ehrenpreis concluded, “Retinol palmitate significantly reduced rectal symptoms of radiation proctopathy, perhaps because of wound-healing effects.”
”The current results can serve as the foundation for future trials examining retinol palmitate in the multi-institutional setting.”