Evaluating therapeutic efficacy of extended shelf-life 90Y glass microspheres in transarterial radioembolization for colorectal cancer: a quantitative FDG PET/CT analysis

Objectives There is a lack of sufficient evidence regarding the use of extended shelf-life (ExSL) Yttrium-90 (Y-90) glass radiomicrospheres in metastatic colorectal cancer (mCRC) patients. We aimed to investigate the efficacy of ExSL Y-90 glass radiomicrospheres with a personalized treatment approach by analyzing F-18-FDG PET/CT quantitative parameters [metabolic tumor volume (MTV) and total lesion glycolysis (TLG)] separately before and after the treatment. Methods A total of 93 radioembolization sessions involving 77 patients were included. Simplicit(90)Y software was utilized to perform multicompartmental voxel-based dosimetry. Adverse events were recorded using the CTCAE v5.0 criteria. The survival data were recorded in detail. Results The overall disease control rate was 84.9%, with a median overall survival (OS) of 12.7 months and median progression-free survival (PFS) of 8.3 months. A statistically significant increase in treatment response rate was observed when there was an increase in absorbed tumor dose for pre-treatment unit MTV (P = 0.005) and TLG (P = 0.004) values. We didn't observe any additional side effects/vital risks that could be considered clinically significant. Conclusion Our study has provided evidence on the therapeutic effectiveness and safety in terms of dose-toxicity profile of ExSL Y-90 glass microspheres in a large cohort of mCRC patients. With a personalized treatment approach, the increase in radiation dose absorbed by the tumor has shown a significant contribution to treatment response rate, as indicated by quantitative measurements obtained through F-18-FDG PET/CT.