The purpose of this trial is to determine the safety of 90Y-hMN14 at different dose levels in the treatment of residual colorectal cancer following recent surgery.

Disease Characteristics:

• Patients with documented histologic and cytologic diagnosis of colon or rectal malignancy
• Patients with documented status post surgical resection of primary cancer or metastases
• Limited residual disease (i.e., CEA serum levels < 15 ng/mL and negative baseline CT scans, or no lesion > 1 cm)

Prior/Concurrent Therapy:

• Patients must have completed chemotherapeutic agents, biologic therapy, radiotherapy, other investigational therapy for cancer, or surgical procedures at least six weeks prior to study entry.
• Patients must have recuperated from surgery and toxicities (as a result of previous therapy) sufficiently prior to study entry
• Biologic Therapy: Patients who have received a murine, chimeric, CDR-grafted (humanized), or human IgG will be eligible provided pre-study evaluations demonstrate no significant reactivity with hMN-14 IgG (i.e., HAHA)
• Radiotherapy: No prior external beam irradiation to a field that includes more than 30% of the red marrow. No prior radiation to maximal tolerable levels for any critical organs (e.g., 3000 cGy for the liver; 2000 cGy for the lungs and kidneys)

Patient Characteristics/Inclusion Criteria:

• Performance Status: Patients with Karnofsky performance status > 70%
• Hematopoietic: ANC >/= 1.5 x 10/L; Hemoglobin >/= 10 g/dL; Platelets >/= 100 x 10/L
• Renal: Serum Creatinine </= 1.5 x ULN
• Hepatic: Serum Bilirubin </= 1.5 ULN; AST and ALT </= 2.5 x ULN; Alk Phosphatase </= 2.5 x ULN
• Cardiovascular: Patients with LVEF >/= 50% by required MUGA/2D-ECHO tests
• Pulmonary: Patients with DF and FEV1 >/= 60% by required Pulmonary Function Tests
• Central Nervous System: Patients with known metastatic disease to the CNS are excluded.
• Other: Patients agreeing to use a medically effective method of contraception during and for a period of three months after the treatment period. A pregnancy test will be preformed on each premenopausal female of childbearing potential immediately prior to entry into study. Patients must understand and give written informed consent.