Primary Objectives:~To evaluate the effect of naproxen or aspirin on the abundance of T cells and other im-mune cell types in the normal colorectal mucosa of participants with Lynch syndrome (LS) using single-cell approaches.~Secondary Objectives:~To evaluate cell-type specific effects of treatment with naproxen or aspirin on gene ex-pression in the normal colorectal mucosa and endometrium in participants with LS using single-cell approaches.~To evaluate the effect of treatment with naproxen or aspirin on the spatial distribution of immune-related cell types in the normal colorectal mucosa and endometrium in of partic-ipants with LS using multiplex imaging approaches.~To assess the effect of treatment with naproxen or aspirin on colorectal polyp burden in participants with LS.~To assess the safety profile of treatment with naproxen or aspirin in participants with LS.~To assess the effect of treatment with naproxen or aspirin in normal mucosa, stool and periodontal microbiome in participants with LS.~To compare the effect of naproxen or aspirin on the abundance of T cells and other im-mune cell types in the normal colorectal mucosa, endometrium and peripheral blood of participants with LS.~To assess the symptoms of LS participants randomized to naproxen or aspirin.
To learn about the effects of naproxen and aspirin on the normal colon in people with Lynch Syndrome.