EGFR and Lynch syndrome: The purpose of this study was three-fold: first, develop organoid models of uninvolved colon and colon polyps from subjects with SPS; second, compare EGFR and COX signaling in colon organoids derived from SPS, FAP and Lynch syndrome; and third, determine the effects of EGFR (erlotinib) and COX (sulindac) inhibitors on colon organoid stem cell growth and differentiation in the three high-risk groups.