Fludeoxyglucose F 18 PET Imaging in Determining Protein and Gene Expression Signatures in Patients With Premalignant Polyps or Colon Cancer

OBJECTIVES:

Primary

• To determine the feasibility of ex-vivo imaging of colon cancer and colon polyps using fludeoxyglucose F 18 positron emission tomography (FDG PET).
• To evaluate the differences in molecular and genetic profiles between FDG-positive polyps and FDG-negative polyps to suggest what gene mutations and abnormal mRNA and/or protein expressions may be required for FDG avidity ("signature" for FDG avidity).

Secondary

• To evaluate the differences in molecular and genetic profiles between FDG-positive polyps and FDG-positive cancers to suggest what gene mutations and abnormal mRNA and/or protein expressions may be required for cancer formation ("signature" for cancer).
• To evaluate the differences in molecular and genetic profiles between normal colonic mucosa, polyps, and cancer.
• To evaluate the differences and similarities in molecular and genetic profiles between FDG-positive cancers and polyps.

OUTLINE: Part I: Patients receive fludeoxyglucose F 18 (FDG) IV followed 45-60 minutes later by surgery to remove part or all of the colon. Tissue samples of the colon undergo positron emission tomography (PET) imaging.

Part II: Tissue samples are analyzed for glucose transporters proteins (Glut-1, 2, 3, 4, 5, 7) via IHC; presence of K-ras mutation (invariable mutant site on codon 12, 13) via PCR; 18q deletion via fluorescence in situ hybridization (FISH) or DCC IHC; MCT-1, Hex-1, Hex-2, and COX-2 expression levels via quantitative RT-PCR method or western blot; APC mutation via PCR- In Vitro Synthesized-Protein Assay or RT-PCR direct sequencing method; p53 mutation detection via immunochemistry, RT-PCR direct sequence methods, and western blot; methylation alteration of MGMT, CDKN2A, HLTF, MLH1, TIMP3, HIF1, BNIP3, and HRK via methylation detecting microchip; and specific gene methylations via methylation-specific PCR. Some tissue samples may be saved and banked for future studies.