胸腺瘤术后放疗疗效与WHO组织学分型和Masaoka分期相关性分析

Prognostic value of WHO histological subtype and Masaoka clinical stage in postoperative radiotherapy for thymoma

目的探讨不同WHO组织学分型及Masaoka临床分期及其他因素与胸腺瘤术后放疗生存率的关系。方法回顾分析2000--2006年间胸腺瘤患者的临床资料，符合入组条件者共94例。其中男40例，女54例，中位年龄46岁。WHO组织学分型AB型3例，B1型7例，B2型22例，B3型44例，C型18例；Masaoka临床分期Ⅰ期9例，Ⅱ期36例，Ⅲ期38例，Ⅳ期11例。所有患者均给予术后常规放疗，中位剂量为5442cGy（4011—6213eGy）。用Kaplan—Meier法计算生存率，Pearson复相关分析组织学分型与分期间的相关性，Cox回归模型用于影响预后的多因素分析。结果随访率91％，5年随访31例。5年总生存率为72％。Masaoka分期Ⅰ、Ⅱ、Ⅲ、Ⅳ期的5年生存率分别为100％、83％、66％、36％。WHO组织学分型AB、B1、B2、B3、C型的5年生存率分别为100％、86％、76％、67％、44％。相关分析发现WHO组织学分型与Masaoka分期具有一定相关性（r=0．614，P=0．000）。多因素分析显示WHO组织学分型、手术切除完全性、肿瘤包膜有无侵犯是影响长期生存的独立预后因素。结论WHO组织学分型、Masaoka分期、手术切除完全性、肿瘤包膜完整与否均为胸腺瘤术后长期生存重要的预后因素。WHO组织学分型与Masaoka分期二者具有一定相关性，两者结合对胸腺瘤术后治疗具有指导意义。

Objective To evaluate the prognositic significance of WHO histological subtype and Masaoka clinical stage in postoperative radiotherapy for thymoma. Methods Between October 2000 and December 2006,94 eligible patients with thymoma were retrospectively analyzed, including 40 male and 54 female. The median age was 46 years. The WHO histological subtypes were type AB in 3 patients, type B1 in 7, type B2 in 22, type B3 44, and type C in 18. The Masaoka clinical staging was stage Ⅰ in 9 patients, stage Ⅱ in 36, stage Ⅲ in 38, and stage Ⅳ in 11. All patients received conventional radiotherapy after thymoma resection. The median dose was 5442 cGy （4011 -6213 cGy）. Kaplan-Meier method was used to calculate survival rate, and correlation analysis method was used to analyze the correlation between WHO histological subtype and Masaoka clinical stage. Cox regression model was used for multivariate analysis. Results The follow-up rate was 91%, with a 5-year follow-up in 31 patients. The 5-year overall survival rate was 72%. According to Masaoka staging system, the 5-year survival rates of stage Ⅰ , Ⅱ, Ⅲ and Ⅳ were 100%, 83%, 66% and 36%, respectively. In patients with WHO type AB, B1, B2, B3 and C, the 5-year survival rates were 100%, 86%, 76%, 67% and 44%, respectively. There was a correlation between WHO histological subtype and Masaoka clinical stage （r = 0. 614,P = 0. 000）. In multivariate analysis, WHO histological subtype, resection completeness and capsule invasion were independent prognostic factors for long-term survival. Conclusions Masaoka clinical stage, WHO histological subtype, resection completeness and capsule invasion are important prognostic factors for long-term survival in patients with thy- morea after surgery. There is a certain correlation between WHO histological subtype and Masaoka clinical stage, and their combination is valuable for guiding postoperative treatment in thymoma.