Is Radioembolization with a Boosted Dose Associated with Favorable Tumor Response?

A new study found that Y90 radioembolization with glass microspheres given at a boosted dose in patients with large hepatocellular carcinomas (HCCs) may show favorable tumor response. The results, which were published in the Journal of Vascular and Interventional Radiology, also found that the higher dose may lead to considerable biliary complications.

In this retrospective study, 80 patients with HCC who underwent Y90 radioembolization with the use of glass microspheres from July 2016 to August 2017 were treated at the study institution. Inclusion criteria included nodular tumor, tumor size >5 cm, Barcelona Clinic Liver Cancer stage A/B disease, target perfused tissue dose >150 Gy, and all tumors treated in a single radioembolization session. Twenty patients met the inclusion criteria and were included. Among the 20 patients, 13 (65%) had a single nodular tumor and 7 (35%) had multiple nodular tumors. The median tumor diameter was 7.6 cm (range, 5.1 – 13.0 cm). A retrospective review of follow-up radiologic findings and clinical outcomes was done until May 2018. Modified Response Evaluation Criteria In Solid Tumors was used to determine tumor response.

At 1 month complete response rates were 25% and at 3 months were 60%. Complete response for the entire liver was achieved in 14 patients (70%) and complete response for the primary index tumor was achieved in 16 patients (80%).

The median follow-up period was 11.6 months (mean, 13.0 months ± 4.2; range, 6.3 – 22.2 months). At 6 months, local progression-free survival and progression-free survival rates were 94.1% and 85.0%, respectively. At 1 year, they were 94.1% and 74.7% at 1 year, respectively.

As of May 2018, all 20 patients were alive and only 1 patient (5%) had progression of the primary index tumor.

Four patients (20%), however had symptomatic (n = 3) or asymptomatic (n = 1) benign biliary strictures.

“In the present study, bile duct stricture requiring antibiotic therapy and biliary drainage developed in 3 patients. Because the perfused volume supplied by the caudate artery is commonly less than 100 mL, the tissue dose supplied by the caudate artery may be excessive. Adjustment of the treatment schedule to reduce activity of glass microspheres at administration might decrease the incidence of biliary complications. If the manufacturer can provide vials smaller than 3 GBq at calibration, adjustment of the treatment schedule may become easier,” the authors concluded.

--Kelsey Moroz

 

Reference

Kim HC, Kim YJ, Lee JH. Feasibility of Boosted Radioembolization for Hepatocellular Carcinoma Larger than 5 cm. J Vasc Interv Radiol. 2018. pii: S1051-0443(18)31326-5. doi: 10.1016/j.jvir.2018.07.002. [Epub ahead of print]