Background: previous RCTs demonstrate calcium+ ASA lower risk of recurrent colon cancer after colonoscopy, and low vitamin D levels associated with elevated CRC risk.
1. n = 2259 patients (ages 45-75) with recent hx of adenomas got daily D3 (1000 IU), CaCO3 (1200mg), both or placebo. Recurrent adenomas and advanced adenomas were the same in all groups at 3- and 5-year followup.
2. n = 1107 patients got vitamin D (0.5 mcg calcitriol), ASA (75mg) and CaCO3 (1250mg) or placebo. At 3 years, the rates of adenoma recurrence were similar between groups.
Comment: The data still stands that ASA and other NSAIDs taken daily for many years likely decreases the risk of CRC in high-risk patients (pos family hx). However, it looks like Ca and vit D don’t.
N Engl J Med 2015 Oct 15; 373:1519
Gastroenterology 2015 Sep 21