- Patients must consent to utilization of tissue for research in this protocol. Tissue will be evaluated via immunohistochemical staining for deoxycytidine kinase, ERCC-1 and ERCC-2 (XPD). Patients may be asked if they are willing to allow their tissue to be used for future studies that are not defined in this protocol. Disallowing the use of tissue for future studies does not limit eligibility in this protocol.