Bone marrow dosimetry for ¹⁴¹Ce-EDTMP as a potential bone pain palliation complex: A Monte Carlo study

Area of Science:

• Nuclear Medicine
• Radiopharmaceutical Therapy
• Medical Physics

Background:

• Metastatic bone cancer requires palliative therapy, often limited by bone marrow absorbed dose.
• 89SrCl2 is an FDA-approved radiopharmaceutical but has limitations.
• 141Ce radionuclide possesses favorable physical properties for potential therapeutic applications.

Purpose of the Study:

• To calculate the bone marrow absorbed dose of the 141Ce-EDTMP complex.
• To compare the bone marrow absorbed dose of 141Ce-EDTMP with 89SrCl2.
• To evaluate 141Ce-EDTMP as a potential alternative radiopharmaceutical for bone metastasis palliative therapy.

Main Methods:

• Utilized the GATE Monte Carlo toolkit for simulations.
• Employed two human bone models: vertebra and femur.
• Calculated bone marrow absorbed doses and bone-to-bone marrow absorbed dose ratios.

Main Results:

• 141Ce-EDTMP demonstrated significantly lower vertebra (29.1 mGy/MBq) and femur (4.3 mGy/MBq) bone marrow absorbed doses compared to 89SrCl2 (109.2 and 16.3 mGy/MBq, respectively).
• The bone-to-bone marrow absorbed dose ratio for 141Ce-EDTMP was higher (vertebra: 34.2, femur: 23.8) than for 89SrCl2 (vertebra: 11.6, femur: 7.5).

Conclusions:

• 141Ce-EDTMP exhibits a favorable profile with lower bone marrow toxicity and higher tumor targeting potential.
• The 141Ce-EDTMP complex is a promising candidate for palliative therapy in patients with bone metastasis.
• Further investigation into 141Ce-EDTMP as an alternative to 89SrCl2 is warranted.