Influences of platelet distribution width on the prognosis of patients with nasopharyngeal cancer

Abstract

Objective To investigate the influences of platelet distribution width (PDW) on the prognosis of nasopharyngeal cancer patients. Methods A total of 186 patients with nasopharyngeal cancer from January 2009 to December 2013 in our hospital were selected. The patients were aged from 48 to 79 years old, with an average age (61.8±8.2) years old. The age, gender, lung function, liver function, body mass index(BMI), smoking, drinking, histological type and staging of patients were recorded. The patients were followed up after discharge, and the mean follow up period was 28 months (12-36 months). The terminal event was nasopharyngeal cancer related death or the end of follow up. The best threshold of receiver operating characteristic (ROC) curve for the overall survival rate of PDW was tested, and the patients were divided into ≥ best thres-hold group and < best threshold group. The prognostic factors were analyzed by single factor analysis and Cox multiple regression analysis. Results The best threshold of ROC curve for the overall survival rate of PDW was 16.4%. The patients were divided into PDW≥16.4% group and PDW<16.4% group. There were no statistically significant differences in age (t=0.712, P=0.478), gender (χ2=0.044, P=0.834), BMI (t=0.593, P=0.554), smoking (χ2=0.063, P=0.802), drinking (χ2=0.555, P=0.456), forced expira-tory volume in one second/forced vital capacity (FEV1/FVC, t=1.711, P=0.089), alanine transaminase (ALT, t=1.756, P=0.081), histological type (χ2=0.259, P=0.879) and staging (Z=2.443, P=0.486) between the two groups. Results of single factor analysis showed that there were statistically significant differences in age (χ2=4.611, P=0.032), gender (χ2=3.952, P=0.047), smoking (χ2=5.564, P=0.018), FEV1/FVC (χ2=4.321, P=0.038), staging (χ2=6.021, P=0.014) and PDW (χ2=4.511, P=0.034) between the two groups. Cox risk model of multifactor analysis showed that the elderly (≥60 years, χ2=5.429, P=0.020), male patients (χ2=4.648, P=0.031), smoking (χ2=18.453, P<0.001), Ⅲ-Ⅳ staging (χ2=9.612, P=0.002) and PDW≥16.4% (χ2=6.008, P=0.014) were independent prognostic factors in patients with nasopharyngeal cancer. Conclusion The degree of PDW in patients with nasopharyngeal cancer affects the prognosis of patients, and the patients with PDW≥16.4% have the better prognosis. Key words: Nsopharyngeal neoplasms; Survival rate; Platelet distribution width