Intended preoperative trans-arterial embolization for large hepatocellular carcinoma: a retrospective cohort study

Background Generally, a large tumor size of hepatocellular carcinoma (HCC) is associated with poor visibility and uncertainty in the surgical field which results in increased surgical difficulty as well as unfavorable postoperative outcomes. We performed intended preoperative trans-arterial embolization (TAE) in patients with a large HCC. In this study, we investigated the oncological significance of intended preoperative TAE for a large HCC, using a comparison between patients with and without TAE, and detailed analyses for pre- and post-TAE status. Methods A total of 411 patients who underwent hepatectomy for primary HCC at the University of Yamanashi Hospital between January 2007 and December 2018 were included in this study. The patients were divided into two groups: patients with larger HCCs (>= 50 mm, n=51) and those with smaller HCC (<50 mm, n=360) according to the size of their HCCs. Comparison of clinicopathological features between these groups and clinical outcomes between the TAE and non-TAE groups were compared. In addition, a detailed analysis of each case in the TAE group was conducted, comparing clinicopathological factors between pre- and post-TAE status. Results The clinical unfavorable short- and long-term outcomes of patients with large HCCs (>= 50 mm) were revealed compared to those with small HCCs (<50 mm). The prognostic analyses showed that a large tumor size and increased tumor markers, multiple tumor numbers, and others were adverse prognostic factors, and vascular invasions and residual tumors were included in the multivariate analysis. Further detailed analyses revealed that the average rates of change in tumor size and tumor shrinkage after TAE were - 48.6 +/- 35.6 mm and - 30.7 +/- 17.0%, respectively. Pathological high necrotic changes in the tumor, after multiple-times TAE aiming to a better effect, were related to a better prognosis in patients with large HCC. Poor prognostic factors became less common in patients who underwent intended preoperative TAE, and these patients had better prognoses. Conclusions The large tumor size of HCC is associated with unfavorable outcomes; the intended preoperative TAE for large HCC patients performed multiple times aiming to affect the tumor as much as possible might improve their prognoses.