Background: Transarterial chemoembolization (TACE) is the most commonly used adjuvant therapy for hepatocellular carcinoma (HCC) after curative resection. Responses to TACE are variable due to tumor and patient heterogeneity. We had previously demonstrated that expression of Granulin-epithelin precursor (GEP) and ATP-dependent binding cassette (ABC)B5 in liver cancer stem cells was associated with chemoresistance. The present study aimed to evaluate the association between GEP/ABCB5 expression and response to adjuvant TACE after curative resection for HCC.

Methods: Patients received adjuvant TACE after curative resection for HCC and patients received curative resection alone were identified from a prospectively collected database. Clinical samples were retrieved for biomarker analysis. Patients were categorized into 3 risk groups according to their GEP/ABCB5 status for survival analysis: low (GEP-/ABCB5-), intermediate (either GEP+/ABCB5- or GEP-/ABCB5+) and high (GEP+/ABCB5+). Early recurrence (recurrence within 2 years after resection) and disease-free survival were analyzed.

Results: Clinical samples from 44 patients who had followed-up for more than 2 years were retrieved for further biomarker analysis. Among them, 18 received adjuvant TACE and 26 received surgery alone. Patients with adjuvant TACE in the intermediate risk group was associated with significantly better overall survival and 2-year disease-free survival than those who had surgery alone (P = 0.036 and P = 0.011, respectively). Adjuvant TACE did not offer any significant differences in the early recurrence rate, 2-year disease-free survival and overall survival for patients in low and high risk groups.

Conclusions: Adjuvant TACE can only provide survival benefits for patients in the intermediate risk group (either GEP+/ABCB5- or GEP-/ABCB5+). A larger clinical study is warranted to confirm its role in patient selection for adjuvant TACE.