976P - Overall survival in advanced hepatocellular carcinoma treated with concomitant systemic therapy and stereotactic radiation therapy or systemic therapy alone

Background

First-line systemic therapy (ST) options in advanced hepatocellular carcinoma (HCC) include tyrosine kinase inhibitors and immunotherapy (IO). Evolving data suggest prolonged overall survival (OS) when ST approaches are combined with stereotactic radiation therapy (SRT), although evidence is limited in HCC populations. We hypothesized that advanced HCC patients in the United States National Cancer Database (NCDB) would have improved OS when receiving ST+SRT vs ST alone.

Methods

Stage III/IV HCC patients diagnosed from 2010-2020 and treated with first-line ST±SRT were identified from the NCDB. The primary endpoint was OS from date of diagnosis stratified by the receipt of SRT (ST+SRT vs ST alone). Survival was estimated using Kaplan-Meier methodology and compared via log-rank. Multivariate analysis (MVA) was performed by Cox regression.

Results

Of 10,505 eligible patients with stage III disease, 115 (1.1%) received ST+SRT and 10,390 (98.9%) received ST alone. Of 9,617 eligible patients with stage IV disease, 127 (1.3%) received ST+SRT and 9,490 (98.6%) received ST alone. Median follow-up time was 6.8 months. Baseline characteristics were similar between cohorts. Patients with stage III disease receiving ST+SRT had improved median OS (12.62 months vs. 8.38, log-rank P=0.0054) and higher rates of survival at 1-year (53.0% vs. 38.7%) and 2-years (27.0% vs. 20.7%) compared to those receiving ST alone. Similarly, patients with stage IV disease receiving ST+SRT had improved median OS (11.79 months vs 5.72 months, log-rank P<0.0001) and higher rates of survival at 1-year (49.6% vs 26.2%) and 2-years (23.6% vs. 12.0%). On MVA, receipt of SRT predicted for improved OS (HR=0.748, P=0.0178) and receipt of IO trended towards improved OS (HR=0.859, P=0.0538). Predictors of poor OS included stage IV disease (HR=1.509), primary tumor size > 5 cm (HR=1.354), and Charlson-Deyo Score >0 (HR=1.106) (P=<0.0001).

Conclusions

In patients with stage III/IV HCC, concomitant ST+SRT improved OS compared to ST alone. Prospective clinical trials are warranted to better identify HCC populations which may benefit from combined modality therapy.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Saint Louis University.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.