Characterization of Rectal Cancer Hypoxia Using pO2 Histography and Immunohistochemistry for Hypoxia-Related Proteins

Characterization of Rectal Cancer Hypoxia Using pO2 Histography and Immunohistochemistry for Hypoxia-Related Proteins

Characterization of Rectal Cancer Hypoxia Using pO2 Histography and Immunohistochemistry for Hypoxia-Related Proteins

The purpose of this study is to see if the cells in rectal cancer are oxygen-starved, or hypoxic. We know that as cancers grow bigger, parts of them are cut off from the oxygen supply and they become hypoxic, basically, lacking oxygen. Research has shown that cells that are oxygen-starved respond differently to treatment such as chemotherapy and radiation when compared to cells that are oxygen rich.

In patients meeting eligibility requirements outlined below, comparisons will be made between direct pO2 measurements using a tissue hypoximeter and IHC-assessed expression of hypoxia related proteins (HIF-1α, VEGF, CA IX and GLUT-1) in both normal and tumor tissue.

Patients consented to the protocol will proceed to their surgery date without any change in the standard preoperative period. After arriving in the operating room, the patient will undergo intravenous general anesthesia (or spinal/epidural anesthesia) by the anesthesiologist and will receive 40% oxygen. At this time, the principal investigator (along with the assistance of the operating surgeon and a member of the Department of Medical Physics) will use the Eppendorf hypoximeter to gather pO2 measurements. We anticipate that this will add no more than fifteen minutes to the planned procedure. Once the measurements are collected, the anesthesia will be adjusted as appropriate for the surgery and the procedure will continue as usual.

Inclusion Criteria: Biopsy proven adenocarcinoma of the rectum. If a biopsy was taken at an outside hospital, the slides and diagnosis will be reviewed and confirmed by a pathologist at MSKCC. Mid to distal rectal tumors not requiring pre-op radiation or chemotherapy Age ≥ 18 Age < 90 Karnofsky performance status ≥ 60 Ability to understand and the willingness to sign a written informed consent document. Exclusion Criteria: Current pregnancy Uncontrolled intercurrent illness that would limit compliance with study requirements.