Pre-clinical in vivo diagnostic of the efficacy of carbon ion therapy in anaplastic thyroid cancer

Ziel/Aim: Despite new advancements for the treatment of anaplastic thyroid cancer, the way to find an effective and less toxic therapy is still challenging. The aim of this study was to investigate the efficiency of carbon ion therapy by performing ¹⁸F-FDG PET/CT in chick chorio allantoic membrane (CAM) xenograft of human anaplastic thyroid cancer cells, which have been previously irradiated.

Methodik/Methods: Human anaplastic thyroid cancer (ATC) cells C643 and two patient-derived cells (Patient 1 and Patient 2) have been seeded in 25 cm² flasks and irradiated once with carbon ion (3 Gy). The next day, the control and irradiated cells have been harvested, mixed 1:1 with matrigel and xenografted in CAM. After 6 days, the survived CAM xenografts, obtained from untreated and irradiated cells, were injected systemically with 10 MBq of ¹⁸F-FDG. The injection was performed through a peripheral vein of the CAM. After 60 minutes of incubation, PET/CT was performed.

Ergebnisse/Results: After irradiation with 3 Gy, the growth of the ATC xenografts, monitored for six days, evidenced that both untreated and irradiated cells were able to grow. However, the xenograft showed a significant difference in size. In particular, the irradiated cells were able to form a three-dimensional mass but smaller than untreated cells, probably because of the irradiation affecting their proliferation. The FDG PET/CT evidenced a strong positive signal obtained from the untreated cells derived xenografts. Instead, the irradiated cell-derived xenografts were absolutely negative on PET/CT scan.

Schlussfolgerungen/Conclusions: FDG-PET/CT appears a valid diagnostic tool for pre-clinical investigation of CAM xenograft derived from carbon ion irradiated anaplastic thyroid cancer cells. Future immunohistochemical analysis of the CAM xenograft viability are expected to further support the current findings.

Publication History

Article published online:
12 March 2025