185例胸腺瘤的临床特点

目的 探讨胸腺瘤及胸腺瘤合并重症肌无力(MG)的临床特征.方法 回顾分析1979年10月～2004年7月外科治疗的185例胸腺瘤患者的临床资料,其中单纯胸腺瘤94例(胸腺瘤组),胸腺瘤合并MG 91例(胸腺瘤合并MG组);手术根治性切除155例(83.8%),姑息性切除16例(8.6%),探查术14例(7.6%).分析两组患者的临床特点;按Masaoka病理分期法进行分期,运用寿命表法计算生存率,分析影响预后的因素.结果 术后死亡5例,其余均缓解或治愈.两组患者的Masaoka病理分期差异有统计学意义(χ2=53.14,P＜0.05);胸腺瘤病理分型与MG临床分型、病理分期差异无统计学意义(χ2=8.21,P＞0.05).胸腺瘤组随访57例,随访1～10年,平均随访40.7个月,1、3、5年生存率分别为70.2%(40/57)、66.7%(22/33)、59.3%(16/27);胸腺瘤合并MG组随访55例,1、3、5年生存率分别为98.2%(54/55)、86.4%(38/44)、81.6%(31/38),比较两组1、3、5年生存率差异无统计学意义(χ2=0.83,P＞0.05).随访112例中,Masaoka病理分期5年生存率分别为Ⅰ期93.7%,Ⅱ期79.2%,Ⅲ期51.4%,Ⅳ期0%,各分期比较差异有统计学意义(χ25年=51.62,P＜0.01).结论 胸腺瘤的病理类型与MG的临床分型无关,胸腺瘤术后生存率与分期显著有关,与是否合并MG无关.胸腺瘤伴MG以全身型为主,病理类型以淋巴细胞型常见.胸部CT检查有助于早期发现胸腺瘤.治疗原则应尽可能广泛切除肿瘤,术后根据具体情况辅以放疗、化疗.手术方式、病理分期对预后影响较大.     

胸腺瘤的外科治疗

目的 总结胸腺瘤的外科治疗经验，以提高手术疗效。方法 102例胸腺瘤患者按Masaoka法分期：Ⅰ期28例，Ⅱ期43例，Ⅲ期26例，Ⅳ期5例。所有患者均采用胸部正中切口和胸前外侧切口进行手术。完整摘除胸腺瘤85例，姑息性切除肿瘤17例。结果 1例胸腺瘤合并冠心病心房颤动患者术后死于心力衰竭。随访101例，随访时间1个月～10年，以寿命表法统计生存率，其Ⅰ期、Ⅱ期非侵袭性胸腺瘤患者的1年、3年、5年和10年生存率分别为97％、90％、84％和57％，Ⅲ期、Ⅳ期侵袭性胸腺瘤的1年、3年、5年和10年生存率分别为87％、74％、71％和23％。结论胸腺瘤为低度恶性肿瘤，积极手术切除肿瘤。可缓解症状、延长生存时间；肿瘤的Masaoka分期与其预后有关。     

胸腺瘤的外科治疗和预后分析

目的探讨外科治疗在胸腺瘤治疗中的作用及预后的影响因素。 方法回顾性分析2004年1月—2017年1月就诊于甘肃省人民医院胸外科并接受手术治疗的55例胸腺瘤患者的临床资料。生存率的计算及单因素生存分析采用Kaplan-Meier法进行,组间差异使用Log-rank检验进行计算,所有经单因素生存分析有意义的参数均纳入多因素生存,采用Cox分析确定与预后相关的因素。 结果55例胸腺瘤患者中,成功随访53例,失访2例。53例患者均接受手术治疗,中位随访时间75.3个月,1、3、5、10年生存率分别为71.1%、56.7%、39.3%和23.3%。单因素分析结果显示：临床症状、肿瘤直径、肿瘤切除范围、Masaoka分期、WHO组织学分类及放化疗对胸腺瘤患者术后长期生存率均有显著影响(P<0.01);多因素Cox分析表明肿瘤切除方式(HR＝5.15,95% CI：1.573～16.883,P<0.05)、肿瘤直径(HR＝5.53,95% CI：1.879～11.797,P<0.05)、WHO分型(HR＝13.23,95% CI：3.015～29.230,P<0.05)、Masaoka分期(HR＝5.18,95%CI：1.597～13.737,P<0.05)以及放化疗(HR＝12.14,95% CI：2.979～49.503,P<0.05)是影响胸腺瘤术后生存率的独立因素。 结论肿瘤直径、肿瘤切除方式、WHO分型、Masaoka分期以及术后放化疗是影响胸腺瘤患者预后的独立因素。     

晚期胸腺癌外科治疗模式的临床研究

目的探讨晚期胸腺癌外科治疗模式与预后的关系。方法回顾性分析进行手术且病理确诊的71例晚期胸腺癌患者的临床资料,按Masaoka分期标准:Ⅲ期55例,ⅣA期16例。均行手术治疗,其中根治性切除29例,姑息性切除25例,探查活检17例。单纯手术治疗10例,术后行放疗30例,化疗2例,放化疗29例。采用Kaplan-Meier法进行生存分析,并进行单因素和多因素分析影响预后的因素。结果单因素分析显示,切除范围、术后放疗与术后放疗+化疗均为晚期胸腺癌患者预后的影响因素(P 0. 05),术后辅助化疗未显示其与预后的相关性(P 0. 05)。多因素COX回归分析显示,切除范围和术后辅助放疗是影响预后的独立因素。结论晚期胸腺癌患者生存期短,治疗应以手术切除为主,同时辅以放疗为一体的综合治疗。     

胸腺瘤患者预后因素分析

目的 探讨影响胸腺瘤患者术后远期生存率的相关因素。方法 回顾性分析我科1973—2000年间手术治疗的69例胸腺瘤，应用Kaplan—Meier法和Cox比例风险模型对可能影响胸腺瘤术后远期生存率的因素进行单因素和多因素分析。结果 全组患者5年、10年、15年生存率分别为83．3％、67．4％、41．9％。单因素分析显示年龄、Masaoka分期、WHO组织学分类、肿瘤切除范围、Rosai／Levine分类对胸腺瘤患者术后长期生存率有显著影响(P＜0．01)，但经多因素分析表明仅Masaoka分期(P＜0．01)、肿瘤切除范围(P＜0．05)、年龄(P＜0．05)是独立的预后因素。结论 对胸腺瘤应积极进行手术治疗，即使姑息性切除亦有助于提高远期生存。     

化疗在胸腺肿瘤治疗中的临床价值:中国胸腺肿瘤研究协作组回顾性研究

目的分析探讨化疗在胸腺肿瘤治疗中的临床应用价值。方法回顾性分析中国胸腺肿瘤研究协作组(the Chinese Alliance of Research for Thymomas,ChART)数据库中1994年3月至2012年12月纳入的MasaokaⅢ/Ⅳa期及胸腺肿瘤化疗病例739例,初步评估不同模式化疗的临床价值,采用Kaplan-Meier法绘制不同亚组患者生存曲线,分析影响预后的因素。结果 Masaoka-Koga分期、手术的根治性和病理学类型是影响患者长期生存的主要因素。初始化疗有效率50.8%(30/59),客观缓解率11.9%(7/59)。初始化疗使R0切除率从66.6%(397/596)提高至72.9%(43/59)。Masaoka-KogaⅢ/Ⅳ期胸腺癌未术后化疗组与术后化疗组5年、10年生存率分别为71.0%、66.6%和53.5%、42.6%,两组间差异无统计学意义(χ~2=0.003,P=0.953)。Masaoka-KogaⅣ期胸腺瘤未术后化疗组与术后化疗组5年生存率分别为85.7%、76.1%,两组间差异无统计学意义(χ~2=0.030,P=0.862)。Masaoka-KogaⅢ胸腺瘤患者未术后化疗组和术后化疗组5年、10年生存率分别为92.1%、65.0%和88.1%、59.6%,未术后化疗组生存率显著优于术后化疗组(χ~2=13.294,P=0.000)。Masaoka-KogaⅢ/Ⅳ期胸腺瘤R0切除后患者未术后化疗组和术后化疗组5年生存率分别为92.8%和67.2%,未术后化疗组生存率也显著优于术后化疗组(χ~2=10.856,P=0.001)。结论初始化疗有提高R0切除率趋势,术后化疗未能改善胸腺肿瘤的总体预后,对于MasaokaⅢ期胸腺瘤和局部晚期R0切除的胸腺肿瘤患者术后化疗无益。     

胸腺瘤合并重症肌无力的外科治疗

目的报告1988年～2000年12月手术治疗36例胸腺瘤合并重症肌无力(MG)的结果.方法全部患者均行手术治疗,按Masaoka临床分期Ⅰ期6例,Ⅱ期15例,Ⅲ期12例,Ⅳ期3例.结果术后18例出现重症肌无力危象,均行气管切开及辅助呼吸,1例死于危象.术后随访半年～10年,3年内MG缓解率为72.2%,5年生存率为65.4%,10年生存率为24.8%.结论胸腺切除手术是治疗胸腺瘤合并重症肌无力的主要方法,术后肌无力危象发生率高,及时行气管切开及辅助呼吸是处理的关键.     

胸腺癌患者的手术预后及其影响因素

目的评估切除情况、病理类型、病理分期及围手术期治疗对胸腺癌手术预后的影响。方法回顾性分析2005年1月至2015年12月北京协和医院胸外科手术治疗56例胸腺癌患者的临床资料,其中男30例、女26例,年龄22~81(52.1±11.5)岁。用Kaplan-Meier法绘制生存曲线,用单因素方差分析评估影响总生存期及无病生存期的因素。结果 R0切除37例(67.9%),其它切除19例(32.1%)。Masaoka分期Ⅰ+Ⅱ期13例(23.2%),Ⅲ期26例(46.4%),Ⅳ期17例(30.4%)。低级别胸腺癌42例,高级别14例。术后放疗、化疗、化放疗及未治疗分别为17例、12例、18例、9例。随访时间1~10年,随访41例,随访率73%。1年、3年、5年生存率分别为93%、74%、61%。切除情况及病理分期影响总生存期,R0切除的术后放疗影响无病生存期,但不影响总生存期。结论手术治疗可以使大部分胸腺癌患者长期生存,R0切除是胸腺癌预后最重要的影响因素。MasaokaⅡ~Ⅲ期的R0切除推荐术后放疗。     

术后放疗在胸腺肿瘤治疗中的临床价值:中国胸腺肿瘤研究协作组回顾性研究

目的探讨术后放疗在Ⅱ、Ⅲ期胸腺肿瘤中的应用价值。方法回顾性分析中国胸腺肿瘤研究协作组(ChART)数据库中1994年4月至2013年3月间的接受手术治疗的Ⅱ期及Ⅲ期胸腺肿瘤病例共870例,最终共有548例符合条件纳入分析,分为术后放疗组(347例)和术后未放疗组(201例)。Kaplan-Meier法分析预后,Cox风险回归模型进行多因素生存分析。结果病理类型、MasaokaKoga分期和手术根治性是胸腺肿瘤主要的预后影响因素。接受根治性手术的胸腺肿瘤患者术后放疗组与未术后放疗组患者的5年、10年生存率分别为87.7%±2.5%、87.8%±4.0%和80.8%±3.6%、83.8%±5.4%,差异无统计学意义(P=0.529,log-rank检验)。接受姑息手术的胸腺肿瘤患者术后放疗组与未术后放疗组的5年、10年生存率分别为73.4%±6.1%、40.4%±15.5%和46.3%±12.4%、40.4%±15.5%,差异有统计学意义(P=0.017,log-rank检验)。胸腺癌患者术后放疗组与未术后放疗组的5年、10年生存率分别为79.3%±3.9%、65.4%±11.1%和49.2%±10.6%、54.5%±13.6%,差异无统计学意义(P=0.054,Breslow检验)。结论术后放疗未能改善根治性胸腺肿瘤的预后,但能改善胸腺瘤姑息切除患者的预后,并有改善胸腺癌患者预后的趋势。     

新辅助化疗肺癌患者长期随访结果分析

目的 探讨新辅助化疗肺癌长期生存率及预后影响因素.方法 回顾性分析1995年6月至2007年5月256例新辅助化疗后进行外科治疗的肺癌患者的临床资料.对性别、年龄、p-TNM分期、肿瘤大小、淋巴结转移情况、病理类型、手术性质和手术方式进行单因素和多因素分析,用Kaplan-Meier法绘制生存曲线和计算生存率,Log-rank检验进行生存率显著性检验.评价可能的预后因素对长期生存的影响.结果 本组手术切除率100%,无手术死亡病例,发生术后并发症11例(4.3%).根治性手术236例(单纯肺叶切除169例,全肺切除53例,扩大切除14例),姑息性手术20例.全组1、3和5年生存率分别为79.3%、38.7%和27.0%.单因素分析显示,年龄、P-TNM分期、肿瘤大小、淋巴结转移情况和手术方式是影响新辅助化疗患者术后长期生存的因素.多因素分析显示,p-TNM分期(0R=1.323,95% CI.068～1.641,P=0.017)和年龄(OR=1.562,95% CI:1.148～2.125,P=0.005)是影响预后的独立危险因素.结论 新辅助化疗可以提高肺癌患者的长期生存率.p-TNM分期和手术方式是影响新辅助化疗患者术后长期预后的主要因素.     

Therapy for thymic epithelial tumors: a clinical study of 1,320 patients from Japan

BACKGROUND: Surgery remains the mainstay of treatment for thymic epithelial tumors, and radiation and chemotherapy also have been applied widely as adjuvant and palliative procedures. METHODS: We compiled records of 1,320 patients with thymic epithelial tumors who were treated from 1990 to 1994 in 115 institutes certified as special institutes for general thoracic surgery by The Japanese Association for Chest Surgery. RESULTS: Patients with stage I thymoma were treated with only surgery, and patients with stage II and III thymoma and thymic carcinoid underwent surgery and additional radiotherapy. Patients with stage IV thymoma and thymic carcinoma were treated with radiation or chemotherapy. The Masaoka clinical stage is an excellent predictor of the prognosis of thymoma and thymic carcinoma, but not thymic carcinoid. In stage III and IV thymoma, the 5-year survival rates of total resection, subtotal resection, and inoperable groups were 93%, 64%, and 36%, respectively. On the other hand, in thymic carcinoma, the 5-year survival rates of total resection, subtotal resection, and inoperable groups were 67%, 30%, and 24%, respectively. Prophylactic mediastinal radiotherapy could not prevent local recurrences effectively in patients with totally resected stage II and III thymoma. Adjuvant therapy including radiation or chemotherapy did not improve the prognosis in patients with totally resected III and VI thymoma and thymic carcinoma. CONCLUSIONS: Total resection is the most important factor in the treatment of thymic epithelial tumors. There is value in debulking surgery in invasive thymoma, but not in thymic carcinoma. We doubt that adjuvant therapy is valuable for patients with totally resected invasive thymoma and thymic carcinoma.     

Which stages of thymoma benefit from adjuvant chemotherapy post-thymectomy?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was 'Which stages of thymoma benefit from adjuvant chemotherapy post thymectomy?' Altogether more than 150 papers were found using the reported search, of which only eight represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated; these studies have mainly reported the survival and recurrence rates of post-thymectomy patients who received adjuvant radiotherapy or chemoradiotherapy, and adjuvant radiotherapy alone was only used in a small group of patients in these studies. We did not find any randomized controlled trials comparing adjuvant chemotherapy with chemo/radiotherapy and, due to a very small incidence of this tumour, it is unlikely to see any trials in future. Studies were mainly retrospective or institutional reports and showed that, despite the high sensitivity of this tumour to chemotherapy agents and the use of chemotherapy as one of the main treatment modalities in the advanced stages of thymoma, current data are not supporting postoperative chemotherapy as a sole adjuvant treatment in advanced stages of thymoma. We conclude that, in patients with thymoma, surgical resection with or without radiation therapy is the gold standard treatment for early-stage disease (I and II). Adjuvant radiotherapy/chemoradiotherapy should be considered for Masaoka stage III (A and B) or above, and it is also advised to add adjuvant therapy for all patients with cortical fenestration, even in stages I and II. But there is no evidence that chemotherapy alone improves the survival in patients with completely resected stage III and IV thymomas and thymic carcinoma. In patients with extra-radiation field disease, however, the use of chemotherapy can potentially improve survival but no follow-up data on this group of patients are available.     

Multimodality Treatment of Thymoma: A Prospective Study

Background. Thymomas are a heterogeneous group of tumors. Treatment of invasive lesions is not well standardized. The aim of this study is to propose a clinicopathologically based protocol for multimodality therapy.

Methods. Between 1965 and 1988, we operated on 83 patients with thymoma who did not receive standardized adjuvant therapy. In 1989, on the basis of the retrospective analysis of the data, we started a multimodality therapy protocol and used it for 65 patients. Twelve patients had medullary thymoma (11 stage I and 1 stage II), 13 had mixed type (6 stage I and 7 stage II), and 40 had cortical thymoma (4 stage I, 11 stage II, 12 stage III, and 13 stage IV). We considered three groups. Group I (n = 18 patients), benign thymoma, included stage I and II medullary and stage I mixed thymomas; radical resection with no adjuvant therapy was performed. Group II (n = 22), invasive thymoma, included stage I and II cortical and stage II mixed thymomas; postoperative chemotherapy plus radiotherapy was always administered. Group III (n = 25), malignant thymoma, comprised stage III and IV cortical thymomas and stage III mixed thymomas; resectable stage III lesions were removed, and highly invasive stage III and stage IV lesions underwent biopsy, neoadjuvant chemotherapy, and surgical resection; postoperative chemotherapy and radiotherapy was administered to all patients.

Results. The 8-year survival rate for patients in stages I, II, III, and IV was 95%, 100%, 92%, and 68%, respectively. Patients with medullary thymoma had a 92% 8-year survival rate; those with mixed type, 100%; and those with cortical thymoma, 85%. Group I had an 8-year survival rate of 94%; group II, 100%; and group III, 76%. Survival was compared with that of patients operated on before 1989: differences were not significant for group I; survival improved in group II (100% versus 81%; p = not significant); and group III showed significant improvement (76% versus 43%; p < 0.049).

Conclusions. Multimodality treatment with neoadjuvant chemotherapy and adjuvant chemotherapy plus radiotherapy may improve the results of radical resection and the survival of patients with invasive and malignant thymoma.     

Intraoperative Chemotherapie nach radikaler Pleurektomie oder extrapleuraler Pneumonektomie

Trimodality treatment including induction and/or adjuvant chemotherapy, surgical resection and in some cases radiotherapy offers a curative intention in selected patients with pleural malignancies (malignant pleural mesothelioma, thymoma with pleural spread). Nevertheless, locoregional tumor recurrence mainly limits the outcome and the quality of life. A few years ago an additional intraoperative chemotherapy perfusion was developed in order to improve local tumor control and prognosis after surgical resection in a multimodality treatment setting. Cytoreductive surgery with the purpose of a macroscopic complete resection could be achieved by radical pleurectomy or extrapleural pneumonectomy. The concept, techniques and perioperative management of this additional treatment option are presented along with a detailed review of the recent literature.     

Adjuvant radiation therapy for stage II thymoma

BACKGROUND: Thymoma is difficult to study because of its indolent natural history. The criteria for administration of adjuvant radiation therapy remain controversial, and it is unclear whether patients with Masaoka stage II thymoma benefit from adjuvant radiation. The goal of this report was to determine whether or not this group benefits from radiation therapy in terms of disease-specific survival and tumor recurrence. METHODS: Case records of the Massachusetts General Hospital were retrospectively reviewed from 1972 to 1999. One hundred fifty-five patients underwent resection for thymoma, of which, 49 had stage II disease. The world literature was reviewed using a Medline search (1966 to 2001), and a secondary review of referenced works was performed. RESULTS: Fourteen stage II patients underwent radiation therapy. Thirty-five did not receive radiation therapy. Baseline prognostic factors between radiated and nonradiated groups were similar. All patients underwent complete resection. The addition of adjuvant radiotherapy did not significantly alter local or distant recurrence rates in stage II thymoma. Disease-specific survival at 10 years in stage II patients was 100% with radiotherapy and without radiotherapy (p = 0.87). There was one recurrence in the nonradiated group at 180 months, which was outside the usual radiation portal. CONCLUSIONS: Most stage II patients do not require adjuvant radiation therapy and can be observed after complete resection.     

Number of recurrent lesions is a prognostic factor in recurrent thymoma

In advanced stage thymomas, recurrence is not uncommon but prognostic factors in recurrent thymoma have not been determined and standardized treatment for recurrence has not yet been established. A retrospective analysis was conducted on 24 thymoma patients who underwent treatment for recurrence in our institution to determine the prognostic factors for overall survival. Recurrence of thymoma appeared 11.6-109.6 months after the primary operation (34.6±25.7 months). Pleural disseminated recurrence was common (n=21) as the primary recurrent lesions. Single or combined modality therapy was performed in 19 patients; surgical resection in 12, radiotherapy in 10, and chemotherapy in six patients. A third surgical resection was performed in two patients. There was no difference in overall survival between the groups with or without treatment nor in those with or without resection. Old age and chemotherapy were factors for poorer prognosis. Patients with one or two recurrent lesions detected on CT examinations showed better prognosis. Prognosis in thymoma patients with recurrence was reviewed in the present study. Patients with a small number of recurrent lesions showed better prognosis irrespective of the treatment.     

Long-term survival and prognostic factors in thymic epithelial tumours.

OBJECTIVE: The aim of this study is to analyze long-term survival and the prognostic significance of some factors after surgical resection of thymic epithelial tumours. METHODS: We performed a retrospective analysis of clinical and histopathological data on 132 patients operated on for thymic tumours, from 1970 and 2001. Histologic diagnosis based on the new WHO classification system was made by a single pathologist. A univariate and multivariate analysis of prognostic factors predicting survival was carried out. RESULTS: There were: 108 complete resections (81.8%), 12 partial resections (9.1%) and 12 biopsies (9.1%). Overall 5, 10 and 15-year survival rate was 72, 61 and 52.5%, respectively. The Masaoka staging system showed 44 stage I, 18 stage II, 52 stage III and 18 stage IV. Histologic results were: 14 subtype A, 31 AB, 20 B1, 28 B2, 29 B3 and 10 C; the respective proportions of invasive tumour (stage II-IV) was 28.6, 58.1, 50, 75, 86.2 and 100%. There were 16 tumour recurrences (14.8%) of 108 radically resected thymomas, 10 were treated with radical re-resection. In univariate analysis, four prognostic factors were statistically significant: radical resection, Masaoka clinical staging, WHO histologic subtype and resectable tumour recurrence. In multivariate analysis, the independent factors predicting long-term survival were WHO histology and Masaoka stage. CONCLUSIONS: The WHO histologic classification seems to be the most significant prognostic factor reflecting the invasiveness of the thymic tumour. Completeness of resection and Masaoka stage I and II assure a better survival. Unresectable recurrence of thymic tumour predicted a worse prognosis.     

Evaluation of the prognostic factors after thymoma resection

We discuss the prognostic factors of thymoma clinicopathologically. Regarding the survival rate by the clinical stage classification of Masaoka, significant correlation was made between stage I and stage III (P < 0.05) and stage I and stage IVa (P < 0.03). The tumor resectability was classified into complete and incomplete resection, and a significant difference was shown by the survival rate of the complete resection at P < 0.0001. Regarding the survival rate by the invasive organ of the tumor, significant correlation was made between no invasion and the great vessel invasion (P < 0.0004) and between invasion except for the great vessel and great vessel invasion (P < 0.004). As for the histological type, the tendency in which the epithelial cell type predominancy increased with the progress of the clinical stage was shown. A significant correlation was not shown in the evaluation by adjuvant therapy. However, recently we have done chemotherapy and/or radiotherapy periodically for invasive thymoma.     

Recurrent myasthenia gravis due to a pleural implant 3 years after radical thymectomy

Although recurrence of a thymoma is rare, pleural dissemination or local relapses have been described. We present a patient who underwent complete thymectomy for a thymoma, type AB according to the World Health Organization classification and stage II according to Masaoka, followed by adjuvant radiotherapy. Three years later, a relapse of the myasthenic symptoms occurred. An isolated pleural implant above the left diaphragm was removed by video-assisted thoracoscopy. Pathology confirmed the recurrence of the thymoma. As this is a rare occurrence, no precise therapeutic guidelines exist. In our case, surgical resection of the recurrence with adjuvant immunomodulating therapy for myasthenia provided good results.     

Results from surgical treatment for thymoma. 43 years of experience.

OBJECTIVE: The biological behavior of thymoma and its prognosis after surgical intervention remain still controversial. The efficacy of surgical treatment for thymoma was investigated by examining long-term follow-up data. SUBJECTS AND METHODS: Follow-up data for patients undergoing surgical resection of histopathologically-confirmed thymoma between 1954 and 1997 were obtained and were retrospectively analyzed. Clinical staging was based on Masaoka's staging system, and histological classification on Rosai's proposed criteria. RESULTS: Data for 140 patients were collected. Sixty-four patients had stage I, 32 had stage II, 28 had stage III, and 16 had stage IV thymoma. There were significant differences in survival between patients with stage I and stage III, stage I and stage IV and stage II and stage III disease, but not between those with stage I thymoma and stage II thymoma. No significant difference in survival was observed between the 56 patients with myasthenia gravis (MG) and the 84 without MG. The 38 patients classified as having a predominantly-epithelial thymoma had a poorer prognosis than the 41 with a predominantly-lymphocytic thymoma. Until 1975, there were four patients with stage I thymomas who later showed recurrence, compared with 21 among those with stage II, III and IV diseases. Since 1976, extended thymectomy with thymomectomy under median sternotomy has been adopted as the standard operation for a thymoma, and there has been no recurrence in stage I patients. CONCLUSIONS: Patients with stage III or IV invasive thymoma have a poorer prognosis and a higher recurrence rate than those with encapsulated thymoma, and patients with a predominantly-epithelial thymoma have a poorer prognosis than those with a predominantly-lymphocytic thymoma. Extended thymectomy with thymomectomy under median sternotomy can be considered as adequate treatment for a stage I thymoma. Myasthenia gravis does not appear to affect the prognosis of patients with a thymoma.