title: Prognostic impact of the mean platelet volume/platelet count ratio in terms of survival in advanced non-small cell lung cancer.
abstract: BACKGROUND
  Mean platelet volume (MPV) is a platelet volume index. Classically, MPV was recognized as a hallmark of platelet activation. Recent studies have revealed that the MPV and MPV/platelet count (PC) ratio can predict long-term mortality in patients with ischemic cardio-vascular disease. In addition, these indices were correlated with the pathophysiological characteristics of patients with various disorders, including malignant tumors.
  
  
  METHODS
  We retrospectively analyzed various hematological indices of patients with advanced non-small cell lung cancer (NSCLC). The aim of this study was to evaluate the contribution of platelet volume indices to survival in these patients.
  
  
  RESULTS
  A total of 268 patients were enrolled in the study. The median age of the patients was 68 years (range: 31-87 years). We compared various hematological indices between the NSCLC group and an age- and sex-matched comparator group. MPV was significantly decreased in the NSCLC group compared to the comparator group. In contrast, the PC was significantly increased in the NSCLC group. Consequently, the MPV/PC ratio was also decreased in the NSCLC group (0.397 vs. 0.501). In receiver operating characteristics (ROC) curve analysis, the MPV/PC ratio was associated with a sensitivity of 62.3% and a specificity of 74.6% at a cutoff value of 0.408730 (area under the curve [AUC], 0.72492)]. Univariate analysis revealed that overall survival (OS) was significantly shorter in the group with a low MPV/PC ratio than in the other group (median survival time [MST]: 10.3 months vs. 14.5 months, log-rank, P=0.0245). Multivariate analysis confirmed that a low MPV/PC ratio was an independent unfavorable predictive factor for OS (hazard ratio [HR]: 1.668, 95% confidence interval [CI]: 1.235-2.271, P=0.0008).
  
  
  CONCLUSIONS
  These data clearly demonstrate that the MPV/PC ratio was closely associated with survival in patients with advanced NSCLC.
authors.affiliation: First Department of Internal Medicine, Kansai Medical University, 10-15 Fumizono-cho, Moriguchi-City, Osaka 570-8507, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Inagaki
authors.affiliation: First Department of Internal Medicine, Kansai Medical University, 10-15 Fumizono-cho, Moriguchi-City, Osaka 570-8507, Japan.
authors.forename: Kayoko
authors.initials: K
authors.lastname: Kibata
authors.affiliation: First Department of Internal Medicine, Kansai Medical University, 10-15 Fumizono-cho, Moriguchi-City, Osaka 570-8507, Japan.
authors.forename: Takeshi
authors.initials: T
authors.lastname: Tamaki
authors.affiliation: First Department of Internal Medicine, Kansai Medical University, 10-15 Fumizono-cho, Moriguchi-City, Osaka 570-8507, Japan. Electronic address: shimizto@takii.kmu.ac.jp.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Shimizu
authors.affiliation: First Department of Internal Medicine, Kansai Medical University, 10-15 Fumizono-cho, Moriguchi-City, Osaka 570-8507, Japan.
authors.forename: Shosaku
authors.initials: S
authors.lastname: Nomura
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001792:Blood Platelets / Q000473:pathology*; D063646:Carcinogenesis; D002289:Carcinoma, Non-Small-Cell Lung / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D002452:Cell Count; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000175:diagnosis* / Q000401:mortality / Q000473:pathology; D008297:Male; D063847:Mean Platelet Volume; D008875:Middle Aged; D009367:Neoplasm Staging; D011379:Prognosis
keywords: Mean platelet volume; Non-small cell lung cancer; Overall survival time; Platelet count; Predictive factor; Retrospective study