Prognostic Factors for Effectiveness Outcomes After Transarterial Radioembolization in Metastatic Colorectal Cancer: Results From the Multicentre Observational Study CIRT

This study explored factors that can predict effectiveness outcomes after transarterial radioembolization in colorectal liver metastases in the liver. In a cohort of 237 patients, among other factors, we found that an Aspartate transaminase to Platelet Ratio Index (APRI) value of > 0.40 was a particularly strong independent predictor of worse overall survival, progression-free survival and hepatic progression-free survival outcomes. Background: Transarterial radioembolisation (TARE) with Yttrium-90 resin microspheres is a treatment option for patients with metastatic colorectal cancer in the liver (mCRC). A better understanding of the prognostic factors and treat-ment application can improve survival outcomes. Methods: We analysed the safety and effectiveness of 237 mCRC patients included in the prospective observational study CIRSE Registry for SIR-Spheres Therapy (CIRT) for indepen-dent prognostic factors for overall survival (OS), progression-free survival (PFS) and hepatic progression-free survival (hPFS) using the Cox proportional-hazard model. Results: The median OS was 9.8 months, median PFS was 3.4 months and median hPFS was 4.2 months. Independent prognostic factors for an improved overall survival were the absence of extra-hepatic disease ( P = .0391), prior locoregional procedures ( P = .0037), an Aspartate transaminase to Platelet Ratio Index (APRI) value of <= 0.40 ( P < .0001) and Inter national Nor malized Ratio (INR) <= 1 ( P = .0078). Partition model dosimetry resulted in improved OS outcomes compared to the body surface area model ( P = .0120). Independent predictors for PFS were APRI > 0.40 ( P = .0416) and prior ablation ( P = .0323), and for hPFS these were 2 to 5 tumor nodules ( P = .0148), Albumin-bilirubin (ALBI) grade 3 ( P = .0075) and APRI > 0.40 ( P = .0207). During the study, 95 of 237 (40.1%) patients experienced 197 adverse events, with 28 of 237 (11.8%) patients having a grade 3 or higher adverse events. Conclusion: Including easy-to-acquire laboratory markers INR, APRI, ALBI and using partition model dosimetry can identify mCRC patients that may benefit from TARE.