Study of Pretargeted Radioimmunotherapy of a Anti-CEA Bispecific Antibody and Lu177-labeled Peptide in Colorectal Cancer

Inclusion Criteria: * Patients with CEA expressing advanced colorectal tumors for which no standard treatment is available * WHO performance status: 0 or 1 * Having normal hematological function: Neutrophils \> 1.5 x 109/l; Platelet count \> 150 x 109/l, without transfusion during the previous month; Hemoglobin \> 5.6 mmol/l * Total bilirubin \< 2 x upper limit of normal (ULN) * ASAT, ALAT \< 3 x ULN * Serum creatinine \< 2 x ULN * Cockcroft clearance \> 50 ml/min * Negative pregnancy test for women of child¬bearing potential (urine or serum) * Age over 18 years * Ability to provide written informed consent Exclusion Criteria: * Known metastases to the brain * Chemotherapy, external beam radiation or immunotherapy within 4 weeks prior to study. Limited field external beam radiotherapy to prevent pathological fractures is allowed, when unirradiated, evaluable lesions elsewhere are present. * Prior angiogenesis inhibitors within 4 weeks; bevacizumab within 8 weeks * Cardiac disease with New York Heart Association classification of III or IV * Patients who are pregnant, nursing or of reproductive potential and are not practicing an effective method of contraception * Any unrelated illness, e.g. active infection, inflammation, medical condition or laboratory abnormalities, which in the judgement of the investigator will significantly affect patients' clinical status * Life expectancy shorter than 6 months.