Taking selenium and vitamin E supplements does not reduce the risk of recurrence in patients with superficial bladder cancer and does not affect disease progression or overall survival. In contrast, vitamin E supplementation may be harmful in this population.
Researchers from the Institute of Cancer Research London, the University of Birmingham and several urology and cancer centers in the UK and the Netherlands studied the effect of selenium and/or vitamin E on the risk of disease progression or recurrence in patients with newly diagnosed superficial bladder cancer. The study results were published in the journal JAMA Network Open.
|Four years of data were analyzed from 270 adult patients with newly diagnosed superficial bladder cancer who were treated at 10 UK centres. The average age was 69 years. Participants were evenly assigned to four groups: selenium (200 micrograms of high micronutrient yeast per day) plus placebo, vitamin E (200 IU d-alpha tocopherol per day) plus placebo, selenium plus vitamin E, and placebo plus placebo. Treatment lasted an average of 1.5 years, observation – more than five years. The periods before relapse, disease progression, as well as safety and overall survival were assessed.
There was no effect of selenium on the relapse-free interval. Surprisingly, vitamin E supplementation was statistically significantly (46%) associated with an increased rate of disease relapse. There were no significant differences in the effect on progression-free survival or overall survival between the two supplements.
A total of 1957 cases of adverse events were reported, 85 of which were reported as serious adverse events. However, all cases were considered unrelated to study treatment.