Determination of the most appropriate radionuclide for knee radiosynovectomy: Assessment of radiation dose, radiation-induced cancer risk, and post-treatment imaging feasibility.

Purpose: This study aims to systematically evaluate all radionuclides used in knee RSV to date and identify the most suitable radionuclide for knee RSV.

Methods: To compare knee RSV with Y-90, P-32, Ho-166, Re-188, Au-198, Lu-177, Sm-153, and Re-186, we measured the radiation dose to non-target organs and the inducing of secondary malignancies in knee RSV patient, the radiation dose to family member and medical staff from the knee RSV patients, and the quality of post-treatment images.

Results: The Lifetime Attributable Risks of cancer incidence and mortality and the Relative Risks of solid cancer incidence and mortality are significantly higher for Y-90 and P-32 in both adult and pediatric patients compared to other radionuclides used in knee RSV. Knee RSV with Re-188, Ho-166, Au-198, and Sm-153 induces a negligible risk of secondary malignancies. The average absorbed dose for medical staff and family members exposed to patients treated with Y-90 is also significantly greater than for those exposed to RSV patients treated with other radionuclides. In contrast, the absorbed dose for medical staff and family members exposed to RSV patients treated with Sm-153, Ho-166, and Au-198 is negligible. Sm-153, Ho-166, and Re-188 offer high-quality images in post-RSV planar imaging.

Conclusion: Based on the findings of this study and the therapeutic range of the radionuclides, Re-188 has been identified as a suitable alternative to Y-90 for knee RSV in adults. At the same time, Sm-153 and Ho-166 have been recognized as the most appropriate radionuclides for pediatric knee RSV.