Who Are the Super Survivors of Y-90 Treatment?

Some patients with unresectable hepatocellular carcinoma (HCC) have prolonged survival after treatment with yttrium-90 radioembolization. Researchers conducted a study to analyze which factors can help predict “Super Survivor” outcomes, which were defined as surviving 3 or more years after Y-90 treatment.

There were 67 Super Survivors found within a database of 1000 patients who received Y-90 from 2003 to 2017. Patients received baseline imaging and then follow-up imaging at 1 month after Y-90 treatment and then continually every 3 months. Overall survival was determined using Kaplan-Meier estimates with log-rank test in subgroups—Child-Pugh score, distribution of disease, portal vein thrombus (PVT), and segmental vs lobar Y-90 technique.

Results revealed that Super Survivor patients had a median age of 69.5 years, with a range of 45 to 94 years. Nearly 70% of the patients were male, while 60% had solitary HCC, 79% had unilobar disease, 12% had portal vein thrombosus, and 10% had ascites.

“While we expected strong survival outcomes in patients with small solitary HCC, 40% of Super Survivors had multifocal disease,” the researchers wrote.

According to the Barcelona Clinic Liver Cancer Stages, 54% were in stage A, 28% in B, 16% in C, and 2% in D. Regarding Child-Pugh scores, 70% of patients were Child-Pugh A, 28% were B, and 2% were C. Either a partial or complete response was seen on imaging in all patients.

The median overall survival for the patients in the study was 67.5 months, but survival greater than 3 years was linked with segmental vs lobar Y-90 treatment, likely as a result of segmental technique sparing the liver in patients who did not have surgical intervention. Those who received segmental survived a median of 80.2 months, compared with 46.7 months for those with lobar treatment. The investigators noted that dosing of greater than 200 Gy did not significantly predict better overall survival in patients.

“Super Survivors spanning the BCLC staging system maintained durable overall survival after radioembolization that was stratified by the extent of underlying liver disease. The common variable among all patients was an imaging response. Segmental versus lobar Y90 may have a long-term associated overall survival benefit,” the study’s authors concluded.

Reference

Gordon AC, Gabr A, Riaz A, et al. Radioembolization Super Survivors: Extended Survival in Non-operative Hepatocellular Carcinoma. Cardiovasc Intervent Radiol. 2018 Jun 12. doi: 10.1007/s00270-018-2008-y. [Epub ahead of print]