Adjuvant Atezolizumab-Bevacizumab after Resection or Ablation for Hepatocellular Carcinoma.

Hepatic resection and radiofrequency ablation (RFA)/ microwave ablation are well-established curative treatments for hepatocellular carcinoma (HCC); however, the disease often recurs [1, 2]. Pathological studies of resected HCC specimens reported that microscopic intrahepatic metastases are present in about 10% of patients with a solitary HCC measuring 2 cm or less. Microvascular invasion is also present in about 27% of patients [3]. Based on these facts, it is believed that there is a certain risk of recurrence of intrahepatic metastasis, even for a single nodule measuring 2 cm or less. Furthermore, the larger the tumor, or the presence of multiple HCCs larger than 2 cm, increases the risk of intrahepatic metastasis and microvascular invasion, and therefore the risk of intrahepatic metastatic recurrence [4, 5]. There are two patterns of recurrence after curative treatment: early and late. Early recurrence involves mainly intrahepatic metastasis via the portal vein, while late recurrence has a more multicentric etiology [2]. About 80% of HCCs recur 5 years after RFA or resection [6]. The main reason for the poor prognosis associated with HCC is frequent recurrence, even after curative treatment. Repeated TACE to treat recurrence worsens liver function in many cases, resulting in death from liver failure. Conversely, if HCC recurrence after curative treatment can be suppressed, the prognosis should improve dramatically. Several adjuvant trials have been conducted to inhibit recurrence, but all yielded negative results [7–9]. To date, representative clinical trials of adjuvants that help to prevent recurrence include a trial of Vitamin K [7], the NIK-333 trial that used retinoid [8], and the STORM trial