Inclusion Criteria:

- Patients must have a Karnofsky performance status of > 60%

- Patients must have histological confirmation of colorectal carcinoma with stage IV
disease or with unresectable disease

- Patients must have colorectal tumors that produce CEA as documented by either
immunohistochemistry or by an elevated serum CEA

- Prior radiotherapy, immunotherapy, or chemotherapy must have been completed no less
than 28 days prior to patient entry on this study and patients must have recovered
from all acute expected side effects of the prior therapy. For patients who have
undergone port placement, study treatment initiation must be at least 7 days post
port placement

- Adequate bone marrow function as evidenced by hemoglobin > 10 g/dL, WBC > 4000/ul, an
absolute granulocyte count of > 1,500/mm^3, and platelets > 150,000/ul; patients may
be transfused to reach a hemoglobin > 10 g/dL

- In the dose-escalation phase, patients may have had a history of a prior malignancy;
for the dose-expansion cohort, patients may have history of prior malignancy for
which they have been disease free for five years with the exception of basal or
squamous cell skin cancers or carcinoma in situ of the cervix

- Patients must have a total bilirubin < 1.5 mg/dL and a serum creatinine of < 2.0
mg/dL

- If a patient has previously received antibody, then serum anti-antibody testing must
be negative

- Serum HIV testing and hepatitis B surface antigen and C antibody testing must be
negative

- Women of childbearing potential must have a negative serum pregnancy test prior to
entry and while on study must be practicing an effective form of contraception

- Patients must have measurable disease as defined by the modified RECIST criteria

Exclusion Criteria:

- Patients who have received radiation therapy to greater than 50% of their bone marrow

- Patients with any nonmalignant intercurrent illness (example cardiovascular,
pulmonary, or central nervous system disease) that is either poorly controlled with
currently available treatment or that is of such severity that the investigators deem
it unwise to enter the patient on protocol shall be ineligible

- Patients with > 2+ protein by dipstick should undergo a 24 hour urine collection;
patients with > 1gram proteinuria/ 24 hours are not eligible

- Patients may have received neoadjuvant and/or adjuvant chemotherapy and/or
radiotherapy and present to the study in relapse; otherwise, no prior therapy is
allowed