- Patients must have histologically confirmed metastatic colorectal cancer, which has recurred or progressed following oxaliplatin- and irinotecan-based chemotherapy regimens administered for the treatment of metastatic disease, except if the patient was not a candidate for either agent or refused treatment with oxaliplatin or irinotecan. The diagnosis must be confirmed by the Laboratory of Pathology at the Clinical Center, NIH (National Institutes of Health), prior to patient enrollment.