Does Bead Size Affect Patient Outcome in Irinotecan-Loaded Beads Chemoembolization Plus Systemic Chemotherapy Regimens for Liver-Dominant Colorectal Cancer? Results of an Observational Study.

Purpose: We investigated the clinical effects of bead size in irinotecan-loaded beads chemoembolization (DEBIRI) used for treating liver-dominant colorectal cancer.

Materials And Methods: Between March 2009 and January 2018, all consecutive patients with colorectal cancer liver metastases referred for DEBIRI at our tertiary center were included in an observational study. Patients were treated exclusively with either 100-mg irinotecan-loaded DC beads of 70-150 μm (small bead group or SB) or 100-300 μm (large bead group or LB) in diameter, in addition to systemic therapy. Liver tumor response rate at 3 months, liver and overall progression-free survival (PFS) and overall survival were estimated.

Results: In total, 84 patients with liver-dominant progressive disease underwent 232 DEBIRI sessions. Fifty-four patients were treated in the SB group and 30 patients in the LB group. Liver progression-free rates at 3 months were 86.7% for the LB group and 79.6% for the SB group (NS). Median liver-PFS and overall PFS were, respectively, 7.15 months and 7.15 months for the LB group and 7.65 and 7.55 months for the SB group (NS). Median overall survival was 13.04 months for the LB group and 15.59 months for the SB group (p = 0.04). Specific treatment grade 3 + 4 toxicity occurrence was 5 (17%) in the LB group and 20 (37%) in the SB group.

Conclusion: No significant difference in patient outcome was observed between DEBIRI bead sizes of 70-150 μm and 100-300 μm. A trend toward higher treatment-specific toxicity was observed with the smaller beads.