3D Voxel-Based Dosimetry to Predict Tumor Response after 90Y Resin Microsphere Radioembolization

Using 3D voxel-based dosimetry in patients with hepatocellular carcinoma (HCC) treated by yttrium-90 (90Y) resin microspheres radioembolization, a new study determined that complete  tumor targeting and 90Y dose to tumor are independent factors associated with clinical outcomes. The results were published in the Journal of Vascular and Interventional Radiology.

In this study, patients with intermediate and advanced stage HCC who received 90Y resin microspheres RE procedures from February 2012 to December 2015 were included. A total of 45 microspheres RE procedures were studied. Using a 3D voxel-based dosimetry to measure 90Y dose deposition, the area under the dose-volume histogram  were calculated. At 6 months, complete/partial response or stable disease on Modified Response Evaluation Criteria in Solid Tumors, and other factors associated with tumor control were investigated. Kaplan-Meier estimates of progression-free survival and overall survival were performed. The occurrence of radioembolization-induced liver disease was used to assess toxicity.

< 0.001) and area under the dose-volume histogram (odds ratio = 1.027; 95% confidence interval, 1.002–1.071; P = 0.033) independently predicted tumor control. An area under the dose-volume histogram ≥ 61 Gy predicted tumor control with 76.5% sensitivity and 75% specificity. In patients with incomplete tumor targeting, PFS were significantly shorter compared with patients with complete tumor targeting (median PFS, 2.7 months [range, 0.8–4.6 months] vs 7.9 months [range, 2.1–39.5 months], P < 0.001). Overall survival in patients with incomplete tumor targeting was also significantly shorter than in patients with complete tumor targeting (median OS, 4.5 months [range, 1.4–23 months] vs 19.2 months [range, 2.1–46.9 months], P < .001).

Median PFS in patients with incomplete tumor targeting and AUDVHtumor < 61 Gy was 2.7 months; incomplete tumor targeting and AUDVHtumor > 61 Gy was 1.8 months; complete tumor targeting and AUDVHtumor < 61 Gy was 6.3 months; and AUDVHtumor > 61 Gy was 12.1 months (P < 0.001)

The occurrence of radioembolization-induced liver disease (n = 4; 9.5%) was associated with higher dose delivered to normal liver (P = 0.04).

The authors concluded that, “complete tumor targeting and 90Y dose to tumor are independent factors associated with tumor control and clinical outcomes.”

--Kelsey Moroz

 

Reference

Allimant C, Kafrouni M, Delicque J, et al. Tumor Targeting and Three-Dimensional Voxel-Based Dosimetry to Predict Tumor Response, Toxicity, and Survival after Yttrium-90 Resin Microsphere Radioembolization in Hepatocellular Carcinoma. JVIR. 2018. Epub ahead of press. DOI: https://doi.org/10.1016/j.jvir.2018.07.006