Liver function as assessed by breath tests in patients with hepatocellular carcinoma

BACKGROUND: Little is known on hepatic function in patients with hepatocellular carcinoma (HCC). Metabolic changes were explored in HCC patients before/after nonsurgical therapy. MATERIALS AND METHODS: HCV-related Child-Pugh A cirrhotic patients with (n = 37) or without HCC (n = 14) and healthy controls (n = 23) were enrolled. Subjects underwent breath testing with (13)C-methacetin or (13)C-ketoisocaproate for exploring microsomal and mitochondrial function, respectively. HCC patients repeated the tests 1-2, 30, and 180 d after radiofrequency ablation (n = 27, RFA) or transarterial chemoembolization (n = 10, TACE). RESULTS: At baseline, cirrhotic patients showed decreased methacetin demethylation capacity compared with controls (8.1 +/- 2.1 versus 13.7 +/- 1.3% cum. dose exhaled at 60 min, M +/- CI, P < 0.001) and minor changes in ketoisocaproate decarboxylation. HCC patients had methacetin demethylation comparable to cirrhotic subjects, but a significantly lower ketoisocaproate decarboxylation (8.5 +/- 1.0 versus 11.6 +/- 1.9% cum. dose exhaled at 60 min, P < 0.001). Methacetin metabolism was significantly decreased following TACE (-28%, P < 0.05) but not RFA. Ketoisocaproate decarboxylation was unaffected by TACE but decreased after RFA (-27%, P < 0.05). A recovery was noticed with ketoisocaproate as a probe after 1 and 6 mo (P < 0.003). HCC recurrence was associated with early decrease of ketoisocaproate decarboxylation. CONCLUSIONS: Liver mitochondrial function is decreased in cirrhotic patients with HCC suggesting a possible tumor-induced suppressant effect. RFA but not TACE appears to spare residual (microsomal) liver mass, but induces such a transient stunning effect on mitochondrial function. Improved mitochondrial function after 1 and 6 mo from RFA may represent an additional parameter of treatment efficacy. Breath test assessing liver function may have potential applications in HCC management