The Death D-Fying Vitamin D3 for Digestive Tract Cancers—The p53 Antibody Connection
Menée au Japon à partir d'échantillons sériques prélevés sur 392 patients atteints d'un cancer du tube digestif et présentant des anticorps sériques et nucléaires anti-p53, cette étude évalue l'effet d'une supplémentation en vitamine D3 sur le risque de récidive et de décès
In 2019, Urashima et al reported results of a randomized, double-blind, placebo-controlled clinical trial that evaluated the efficacy of improving relapse-free survival for patients with cancers of the digestive tract who received 2000 IU vitamin D3 supplementation daily for 8 years. Based on the results from this clinical trial, the authors concluded that vitamin D3 supplementation did not improve relapse-free survival at 5 years. In this issue of JAMA Network Open, Kanno et al report a post hoc subgroup analysis of this clinical trial. They evaluated the p53-immunoreactive subgroup defined by positivity for both anti-p53 antibodies in serum and nuclear accumulation of p53 by immunohistochemistry in more than 99% of cancer cells, which was considered a biomarker for p53-missense mutations. Patients who had detectable serum anti-p53 antibody and received 2000 IU daily had a significant, more than 2.5-fold improvement in relapse or death compared with the placebo group that had detectable p53 immunoreactivity. The observed 27% absolute risk reduction translates to a number needed to treat of 4. In those patients who had no p53 immunoreactivity, 2000 IU of vitamin D3 daily provided insignificant benefit for 5-year relapse-free survival.