Administer 20 to 30 mCi of Tc-99m labeled CEA-Scan and image 2 to 5 hrs post injection. To ensure proper patient hydration, it is best to have the patient drink plenty of fluids the day before the injection and stop taking additional fluids at time of injection. Hydration in this manner may minimize artifacts resulting from bladder-filling if the patient is not catheterized. Another benefit is a lower concentration of CEA-Scan in the kidneys, which often helps reduce artifacts.

CEA-Scan should not be administered to patients with hypersensitivity to murine derived products. Patients who have previously received murine derived monoclonal antibodies have a greater chance of developing HAMA, which increases the risk of allergic reactions, and altered biodistribution of CEA-Scan . HAMA may also interfere with two-site mMab based immunoassays, such as for CEA or CA-125. If HAMA is suspected, notify the clinical laboratory that interference might occur. Adverse reactions observed with CEA-Scan include transient eosinophilia, nausea, bursitis, urticaria, generalized itching, headache, upset stomach and fever. There has been one report of a grand mal epileptic seizure in a severely hypertensive patient that may have been possibly related to CEA-Scan infusion. Anaphylactic and other hypersensitivity reactions can occur following administration of mouse protein. Although serious reactions of this type have not been observed in clinical trials after CEA-Scan administration, medications for the treatment of hypersensitivity reactions (epinephrine, antihistamines and corticosteroids) should be available for immediate use in the event of an allergic reaction. A prudent practice is to monitor patients’ vital signs for about 20 minutes following after the injection of any protein-derived product. Before using CEA-Scan, be sure to check the latest prescribing information supplied with each package.

Unless medically contraindicted bladder catheterization prior to imaging is recommended for the patient with suspected disease within the pelvis. Urinary catheter should also be strongly considered for any patient who cannot empty the bladder, such as patients with benign prostatic hypertrophy (BPH). In high-risk patients, such as those with compromised immune systems as a result of age or disease, antibiotic therapy for asymptomatic bacteriuria should be considered. If bladder catheterization is being considered, the Nuclear Physician should consult with the patient's Doctor to determine if there are any contraindications.

The time between the injection and the scan can be used to catheterize the bladder, or for changing the ostomy bag. Activity within the ostomy bag can complicate scan interpretation. If the patient has a colostomy, the bag MUST be changed prior to imaging.