Dr. Dawson on the Addition of SBRT to Sorafenib in Locally Advanced HCC

Laura Dawson, MD, FRCPC, clinician scientist, Princess Margaret Cancer Centre in Toronto, Ontario, Canada, discusses results from the phase 3 NRG/RTOG 1112 trial (NCT01730937) of stereotactic body radiation therapy (SBRT) plus sorafenib (Nexavar) compared with sorafenib alone in patients with locally advanced hepatocellular carcinoma (HCC).

Findings presented at the 2023 Gastrointestinal Cancers Symposium showed that patients treated with SBRT/sorafenib experienced a median overall survival 15.8 months (90% CI, 11.4-19.2) vs 12.3 months (90% CI, 10.6-14.3) with sorafenib alone (HR, 0.77; 90% CI, 0.59-1.01; 1-sided P = .55).

Patients in the SBRT/sorafenib arm also achieved an improvement in progression-free survival (PFS). Those treated with SBRT plus sorafenib had a median PFS of 9.2 months (95% CI, 7.5-11.9), compared with from 5.5 months (95% CI, 3.4-6.3) for those given sorafenib alone (HR, 0.55; 95% CI, 0.40-0.75; P = .0001). Moreover, patients in the SBRT/sorafenib arm experienced a median time to progression of 18.5 months, vs 9.5 months for patients in the sorafenib monotherapy arm.

The study enrolled patients with aggressive locally advanced HCC with a sum of tumor mass of up to 20 cm. Dawson notes that patients were also permitted to have any degree of vascular invasion and up to 3 cm of extrahepatic spread. Excluding vascular invasion, patients had a median baseline tumor size of 7.8 cm (range, 1-19.1).

Additionally, 74% of patients had vascular invasion, which was higher than any randomized phase 3 study to date, according to Dawson. The majority of patients with vascular invasion had invasion into the main right or left portal vein, which is associated with worse prognosis, making this a difficult-to-treat subgroup of patients.

Patients were randomly assigned to receive 400 mg of oral sorafenib twice daily, or between 27.5 and 50 Gy of SBRT in 5 fractions, followed by 200 mg of oral sorafenib twice daily for 4 weeks.