Exploring the Potential of High-Molar-Activity Samarium-153 for Targeted Radionuclide Therapy with [(153)Sm]Sm-DOTA-TATE

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.

153Sm-labeled Fe3O4@lapatinib nanoparticles as a potential therapeutic agent for breast cancer: synthesis, quality control, and in vivo evaluation

The present study introduces Fe3O4-coated lapatinib-labeled 153Sm nanoparticles (denoted as Fe3O4@lapatinib-153Sm) as a promising avenue for advancing breast cancer treatment. The radiolabeled nanoparticles combine various attributes, offering enhanced therapeutic precision. The integration of lapatinib confers therapeutic effects and targeted delivery. The inherent magnetic characteristics of Fe3O4 nanoparticles contribute to improved imaging contrast and targeted localization. Incorporating the gamma-emitting 153Sm isotope permits single-photon emission computed tomography imaging and radiation dose evaluation, while its beta-emitting nature ensures targeted cancer cell eradication. The synthesis of Fe3O4@lapatinib-153Sm was meticulously optimized by investigating the effects of parameters on radiolabeling efficiency. Physicochemical attributes were scrutinized using several analytical techniques. In-depth in vivo assessment evaluated the biocompatibility, toxicity, and biodistribution in a murine model, illuminating clinical utility. Optimal conditions (153SmCl3 concentration of 10 mCi mL-1, pH 7.4, a reaction time of 30 min, and a temperature of 25 °C) achieved >99% labeling efficiency and radiochemical purity. The TEM analysis indicated that the diameter of Fe3O4@lapatinib-153Sm nanoparticles ranged from 10 to 40 nm. Vibrating-sample magnetometry verified their superparamagnetic behaviour with a saturation magnetization of 41.4 emu g-1. The synthesized radiopharmaceutical exhibited high sterility and in vitro stability. Acute toxicity studies showed the mild effects of Fe3O4@lapatinib-153Sm at a dose of 20 mCi kg-1, with no observed mortality. Notably, lesions from Fe3O4@lapatinib-153Sm use recovered naturally over time. Radiation doses below 20 mCi kg-1 were recommended for clinical trials. The biodistribution study in BT474 xenograft mice revealed rapid clearance of Fe3O4@lapatinib-153Sm within 48 h. Significant accumulation occurred in the liver, spleen, and tumor tissue, while minimal accumulation was found in other tissues. Future steps involve studying biocorona formation and therapeutic efficacy on tumour models, refining its clinical potential.

Recent Pre-Clinical Advancements in Nuclear Medicine: Pioneering the Path to a Limitless Future

The theranostic approach in oncology holds significant importance in personalized medicine and stands as an exciting field of molecular medicine. Significant achievements have been made in this field in recent decades, particularly in treating neuroendocrine tumors using 177-Lu-radiolabeled somatostatin analogs and, more recently, in addressing prostate cancer through prostate-specific-membrane-antigen targeted radionuclide therapy. The promising clinical results obtained in these indications paved the way for the further development of this approach. With the continuous discovery of new molecular players in tumorigenesis, the development of novel radiopharmaceuticals, and the potential combination of theranostics agents with immunotherapy, nuclear medicine is poised for significant advancements. The strategy of theranostics in oncology can be categorized into (1) repurposing nuclear medicine agents for other indications, (2) improving existing radiopharmaceuticals, and (3) developing new theranostics agents for tumor-specific antigens. In this review, we provide an overview of theranostic development and shed light on its potential integration into combined treatment strategies.

Radiopharmaceuticals for Cancer Imaging and Therapy

Nuclear medicine has emerged as a pivotal player in cancer patient care, revolutionizing the way cancer is detected, diagnosed, monitored, and treated [...].