目的：針對侵襲性胸腺瘤術後患者，探討相關之預後因子與術後輔助性放射線治療的模式。材料及方法：本研究包含63 位侵襲性胸腺瘤患者。所有病患均接受手術，其中49 位病患接受術後輔助性放療。回顧分析病人相關特徵如年齡、性別、胸腺瘤期別、有無重症肌無力以及治療相關因子如手術切除程度、放射線劑量與照野。結果：五年之存活率以及無病之存活率分別為83% 及81.5% 。最常見之復發位置為肋膜復發。單變項分析發現Mosaoka 期別與手術切除程度為重要之預後因子。第II 期與第III/IV 期病人之5 年存活率分別為95.8% 與71.9%（p= 0.06）。手術達到完全切除相較於顯微鏡下或巨觀殘存腫瘤的患者的5 年存活率分別為87.3% 與44.4%（p= 0.04）。接受大範圍縱膈腔或縱膈腔及鎖骨上淋巴照射的病人，與接受小範圍腫瘤切除周圍照射的病人在5 年的存活率沒有統計上顯著差異，分別為88% 與94.7%（p= 0.53）。在無病存活率方面，本研究並未找到重要的預後因子。結論：本研究發現手術切除程度為侵襲性胸腺瘤最重要之預後因子。預防性照射縱膈腔對治療結果並無顯著進步。

Purpose : To investigate the prognostic factors associated with outcome in patients with invasive thymoma undergoing surgery with or without adjuvant radiotherapy and strategies for optimal adjuvant radiotherapy.
Methods and Materials : This retrospective study included 63 patients with invasive thymoma. All patients received surgery and 49 patients underwent adjuvant radiotherapy.Patient characteristics and treatment related parameters were analyzed to correlate with overall survival and disease free survival. Results : The 5-year overall survival and disease-free survival rate was 83% and 81.5%, respectively. The most common site of failure is pleural seeding. The univariate analyses showed that Mosaoka stage and extent of surgical resection were important prognostic factors. The 5-year overall survival rate was 95.8 % in stage II thymoma and 71.9% in stage III/IV thymoma (p= 0.06). The 5-year survival rate was 87.3% for those who underwent complete resection compared with 44.4% for those with microscopic or gross residual disease (p= 0.04). Patients receiving extendedfield or involved-field radiotherapy had similar 5-year overall survival (88% versus 94.7%, p= 0.53). In this study, we can not identify significant prognostic factors for disease free survival.
Conclusion : In our study, the extent of resection is important prognostic factor for invasive thymoma. Extensive radivation field covering mediastinum is not associated with better outcome.