Bexxar Therapy

Indications:
-Threatment of patients with:
  • Non hodgkins lymphoma (follicular)

Contraindications:
Patients with known hypersensitivity to murine proteins.

Questions asked in Patient History:

List the common questions asked when taking a patient history for this specific procedure.
  1. Are you allergic to murine proteins?
  2. Have any allergies towards any medications?
  3. Are you taking any medication?

Radiopharmaceutical information:
  • Radionuclide: I-131
  • Radiopharmaceutical: I-131 Bexxar (tositumomab)
  • Adult dosing: 5mCi
  • Pediatric dosing:
  • Method of administration: I.V. butterfly (18-22 gauge) over 20 minutes
  • Method of Localization: compartmental, blood flow
  • Physical Half-life: 8 days

Patient Preparation:

What does the patient need to do prior to coming for the procedure?


Obtain a signed consent form from patient for the 131 therapy.
Obtain appropriate written directives for iodine dosages.
Ensure patient supplies list of history of allergies and prior exams.
Female patients of childbearing age should be advised to avoid becoming pregnant during ther-apy.
Pregnant females should be counselled as to the potential hazard to the fetus.
Patients who have had a previous Moab test should have a HAMA titer (human anti-mouse anti-body) performed before another injection.
Patient should have > 50,000/mm3 platelet count and ANC > 800/mm3
Patient to receive thyroid-blocking medication at least 24 hours before and continuing until 14 days after the therapeutic dose.
Patient to be medicated with 650 mg acetaminophen and 50 mg diphenhydramine PO beforereceiving the cold tositumomab.
Platelet counts should be taken before regimen and continued for 10 weeks or longer
•TSH levels and serum creatinine should be monitored.
Patient should be well hydrated before 131 dosing


Side Effects:

Will the patient feel any different during or after the procedure?
  • neutropenia
  • thrombocytopenia
  • asthenia
  • fever
  • nausea
Equipment Used:
Type of Camera or Probe
Gamma camera, full FOV
Collimator used: High energy

Acquisition Setup:

Photopeak(s): 364 KeV

Window(s): 15-20%


Dynamic: View(s)
Matrix:
Time/Frame:
Number of Frames:

Statics: View(s)
Matrix: 128x128 or 256x256
Total Counts or Duration: 600 seconds or 1000k counts per view

Whole body: View(s)
Matrix: 128x128 or 256x256
Scan Speed: 10cm/minute
Start/stop points:

SPECT:
180 or 90 degree configuration
Total Rotation: 180 or 360
Starting point:
Matrix:
Time/Azmuiths
Number of Azmuiths:

Processing:


Filter:
Cut-off:
Frequency:


Procedure:
Describe the procedure from verifying the requisition to completing the scan. Include any patient instructions pre- or post- injection/scan, delays between injection and imaging, and any side effects.
Day 0: administer SSKI 4 drops TID or potassium iodide: 130 mg QD (started 2 days before and continued for 2 weeks post procedure)
Day 1: premedicate: acetaminophen, diphenhydramin, pretreatment with Tositumomab-450 mg over 60 minutes, I-131 Bexxar- 5 mCi over 20 minutes, dosimitery WB scan prevoid image
Day 2,3, or 4: WB dosimetery scan
Day 6 or 7: WB dosimetery scan, calculate patient specific dose
Day 7 up to day 14: Therapy administration, pretreat w/tositumomab, therapy dose I-131 Bexxar over 20 minutes


Normal Uptake and common varients:
Insert an image of a normal scan. Describe the normal uptake, and any normal varients visualized.
Fig-1-8892.jpg
This image shows an administration of Bexxar for three days and then therapeutic administration.

http://www.molecularimagingcenter.org/index.cfm?PageID=8892

Abnormal Uptake and causes:
Insert an image of an abnormal scan. Describe the abnormal uptake, and the cause of the abnormal uptake.
F2.medium.gif
Anterior whole body images after injection, splenic uptake.

http://tech.snmjournals.org/content/30/3/109/F2.expansion.html

Artifacts:
Insert an image with an artifact, and explain what the artifact is.
F5.medium.gif
star artifact

http://tech.snmjournals.org/content/30/3/109/F2.expansion.html

References:

http://www.gsk.ca/english/docs-pdf/Bexxar_PM_20071220.pdf
Shackett, Pete. Nuclear Medicine Technology: Procedures and Quick Reference. Philadelphia: Wolters Kluwer Health/Lippincott Williams & Wilkins, 2008. Print.