The indications for tumor mass reduction surgery and subsequent multidisciplinary treatments in stage IV hepatocellular carcinoma.

The indications for tumor-mass reduction surgery and subsequent immunotherapy in patients with stage IV hepatocellular carcinoma (HCC) were elucidated in this study. About 42% of the resected specimens from stage IV-A patients (n = 26) contained well-differentiated multicentrically occurring HCC, which was not found in any of the stage IV-B patients (n = 9). The 2-year survival rate after reduction surgery was 49% for the stage IV-A patients and only 13% for the stage IV-B patients, while 6 of the stage IV-A patients who survived for more than 2 years had no vascular invasion or distant organ metastases. Some of the stage IV patients maintained normal peripheral natural killer (NK) activity and were also able to tolerate surgical insults immunologically, provided that appropriate postoperative immunotherapy was given. Thus, stage IV-A HCC has a greater possibility of containing slow-growing intrahepatic tumor clusters, and the removal of any rapidly growing tumors from among these should be undertaken by reduction surgery followed by subsequent multidisciplinary treatment for residual tumor cells, including appropriate immunotherapy.