title: Involvement of platelets in extrahepatic metastasis of hepatocellular carcinoma.
abstract: OBJECTIVE
  Recently, a relationship between platelets and cancer metastasis has been reported. The aim of this study is to elucidate the risk factors for extrahepatic metastasis (EHM), with emphasis on association with platelets in patients, with hepatocellular carcinoma (HCC).
  
  
  METHODS
  We examined risk factors for EHM in 1613 consecutive, newly diagnosed HCC patients by logistic regression analysis (case-control study). We also examined the factors by Cox proportional hazard model in a retrospective cohort fashion in 803 patients who received non-curative treatment for HCC.
  
  
  RESULTS
  In the case-control study, multivariate analysis revealed that high platelet counts (odds ratio [OR] = 4.84; 95% confidence interval [CI] = 1.29-29.54; P = 0.01), high tumor number and the presence of macroscopic vascular invasion were significantly associated with EHM. In the cohort study, EHM was diagnosed in 71 patients during the study period (mean observation time = 23.3 months). On multivariate analysis, high tumor number, high des-γ-carboxyprothrombin (DCP) and Child-Pugh class A were significantly correlated with EHM, and the patients with high platelet counts tended to develop EHM (OR = 1.73; 95% CI = 0.99-3.14; P = 0.055).
  
  
  CONCLUSIONS
  HCC patients with high platelet counts, as well as large numbers of tumors, high serum DCP and Child-Pugh class A, are at risk for EHM.
authors.affiliation: Department of Gastroenterology and Hepatology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
authors.forename: Yuki
authors.initials: Y
authors.lastname: Morimoto
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Nouso
authors.forename: Nozomu
authors.initials: N
authors.lastname: Wada
authors.forename: Yasuto
authors.initials: Y
authors.lastname: Takeuchi
authors.forename: Hideaki
authors.initials: H
authors.lastname: Kinugasa
authors.forename: Koji
authors.initials: K
authors.lastname: Miyahara
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yasunaka
authors.forename: Kenji
authors.initials: K
authors.lastname: Kuwaki
authors.forename: Hideki
authors.initials: H
authors.lastname: Onishi
authors.forename: Fusao
authors.initials: F
authors.lastname: Ikeda
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Miyake
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Nakamura
authors.forename: Hidenori
authors.initials: H
authors.lastname: Shiraha
authors.forename: Akinobu
authors.initials: A
authors.lastname: Takaki
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Yamamoto
keywords: extrahepatic metastasis; hepatocellular carcinoma; platelet counts; prognosis