P2/MS is known as a simple, accurate, and noninvasive marker for determination of the degree of hepatic fibrosis in patients with viral hepatitis. We aimed to validate P2/MS in patients with HCC.

Consecutive HCC patients who underwent surgical resection between June 2007 and March 2009 at Seoul National University Hospital were enrolled. Fibrosis stage was reviewed and assessed according to METAVIR scoring. P2/MS values [platelet count (10⁹/L)]²/[monocyte fraction (%)×segmented neutrophil fraction (%)] and other noninvasive fibrosis scoring systems were calculated.

A total of 171 patients were included; seven patients with METAVIR F1, 31 with F2, 41 with F3, and 92 with F4. The area under the receiver-operating characteristic curve of P2/MS was 0.804 [95% confidence interval (CI), 0.681~0.927] for detection of significant fibrosis (F2-F4) and 0.769 (95% CI, 0.698~0.839) for detection of histological cirrhosis (F4). At a value < 62, P2/MS detected significant fibrosis with a specificity of 85.7% (95% CI, 42.0~99.2) and a positive likelihood ratio of 4.268 (95% CI, 0.692~26.309); and at a value > 115, P2/MS ruled out significant fibrosis with a sensitivity of 90.2% (95% CI, 84.4~94.1) and a negative likelihood ratio of 0.34 (95% CI, 0.106~0.095). P2/MS had a superior efficacy for detection of hepatic fibrosis in patients with HCC compared to the other noninvasive panels.

P2/MS can accurately detect fibrosis in patients with HCC. Thus, P2/MS might be utilized as a noninvasive index reflecting the degree of hepatic fibrosis in HCC patients.