MSH2 and colorectal carcinoma: Aspirin. A randomized controlled trial by Burn (2020) estimated a CRC HR for individuals with an MLH1, MSH2, or MSH6 PV taking 600mg of aspirin per day, compared with those not taking aspirin, to be 0.56 at 2 years from the start of the intervention, 0.63 at 5 years, and 0.65 at 10 years [14].