Sorafenib for hepatocellular carcinoma managed by non-oncologists: Impact on drug exposure and survival.

Abstract

404 Background: Few data exist on practitioner type, initial dosing regimens, and survival for patients with HCC treated with sorafenib in a real-world setting. Methods: HCC patients exposed to sorafenib were identified from the VA CDW using ICD9 codes and pharmacy records. ICD9 codes, CPT codes, AUDIT-C surveys and laboratory tests were utilized to characterize underlying liver disease, calculate Child-Turcotte-Pugh (CTP) and MELD scores. Two abstractors achieved 100% chart verification of tumor number, size, macrovascular invasion and extrahepatic spread on imaging immediately proximate to sorafenib initiation to quantify Barcelona Clinic Liver Cancer (BCLC) stage and to determine the provider specialty initiating sorafenib. Results: 4838 patients prescribed sorafenib for HCC between 2008 and 2015 were included in this interim analysis. Median age was 62; 98.8% were male, 61.8% white/26.0% black; 44% EtOH/54% HCV/5% HBV/29% other; CTP A 58%/B 37%/C 4%; median MELD 11; 96% ECOG < 2; and pre-sorafenib BCLC 0-0%/A-5%/B-37%/C-49%/D-8%. Sorafenib was prescribed by oncologists (92%), GI/hepatologists (7.6%) and other practitioners (0.4%). Patients treated by GI/hepatologists rather than oncologists had similar BCLC distributions, similar treatment durations (median 90 vs. 90 days), received more pills (median 360 vs. 240, p = 0.0016), but had identical survival (median 234 vs. 239 days, p = NS). Hepatologists were more likely than oncologists to uptitrate during the first month (25% vs. 14%, p < 0.0001) whereas oncologists were more likely to uptitrate later (8.9% vs. 3.8%, p < 0.001). Oncologists were more likely to stop sorafenib due to progression (29 vs. 18%), while hepatologists were more likely to continue sorafenib until death (28 v. 18%) with no difference in discontinuation for AEs or functional decline. In multivariable models including CTP, BCLC, and ECOG PS, prescriber specialty had no impact on OS. Conclusions: In the VA, 8% of sorafenib is prescribed by GI/hepatologists. Despite modest differences in prescribing practices, hepatologists and oncologists achieve similar sorafenib exposure and overall median survival rates of 7.8 months in real-world practices.