Erlotinib Completed Phase 2 Trials for Stage IIIC Rectal Cancer / Recurrent Colon Cancer / Recurrent Rectal Cancer / Stage IIB Colon Cancer / Stage IIC Rectal Cancer / Stage IIIA Colon Cancer / Stage I Colon Cancer / Stage IIIC Colon Cancer / Stage IIIB Colon Cancer / Adenomatous Polyps / Stage IIB Rectal Cancer / Stage IIC Colon Cancer / Stage IIIB Rectal Cancer / Stage I Rectal Cancer / Stage IIA Rectal Cancer / Stage IIA Colon Cancer / Stage IIIA Rectal Cancer Prevention