Clinical significance of relationship between the myasthenia gravis and the WHO histological type & Masaoka clinical stages of thymoma

Objective To investigate the clinical significance of relationship between the myasthenia gravis and WHO histological types & Masaoka clinical stage of thymoma.Methods Retrospective analysis of resection specimen in thymoma and complete medical records in 81 cases from December 2004 to September 2009,using the analysis of statistical software between myasthenia gravis and both thymoma Masaoka clinical stages & the WHO histological types.Results The difference of merger with MG of thymoma Masaoka among different clinical stages was statistically significant (P ＜ 0.05).The difference of merger with MG Thymoma WHO among different histological types was statistically significant (P ＜ 0.05).The difference of thymoma Masaoka between the WHO histological type and Masaoka clinical stages was statistically significant (P ＜ 0.05,kappa =0.580,C =0.503).Conclusions There are some relationships between thymoma Masaoka clinical stages and MG,so had some relationships between thymoma WHO histological types and MG.At the same time,the thymoma WHO histological types reflects the Masaoka clinical stages in a certain extent.This relationship would be used as one of the important indicators to evaluate the prognosis of patients at some extent. Key words: Thymoma ;  WHO type;  Masaoka stage ;  Myasthenia gravis ;  Correlation ;  Prognosis