合并重症肌无力的胸腺瘤治疗与预后特点分析

目的 探讨合并重症肌无力(MG)的胸腺瘤与单纯胸腺瘤在临床病理特点上的差别.方法 回顾性分析1992年1月至2007年12月首都医科大学附属北京同仁医院胸外科采用手术治疗的胸腺瘤患者228例.其中男性102例,女性126例;年龄24 ～ 79岁,中位年龄51岁.根据是否合并MG分为复合组(125例)和单纯组(103例).根据WHO组织分型和改良Masaoka临床分期对胸腺瘤进行分型和分期.手术方式包括胸骨正中劈开153例,胸腔镜手术75例.按美国重症肌无力协会标准进行疗效判断.采用x2检验比较两组的临床特征,Cox生存分析比较两组治疗效果.结果 全组无术中死亡.复合组6例、单纯组13例未切除胸腺瘤(x2=4.52,P =0.035).复合组无A型胸腺瘤和胸腺癌患者,单纯组这两者的比例分别为10.5％(11/103)和11.6％(12/103).复合组和单纯组瘤周围胸腺组织胸腺增生比例分别为28.8％ (36/125)和5.8％ (6/103)(x2=20.91,P=0.000),复合组3例于瘤周围胸腺组织中发现微小胸腺瘤.复合组Ⅲ和Ⅳ期胸腺瘤占24.8％(31/125),单纯组这一比例为33.0％(34/103).198例患者获得随访,随访率86.8％(198/228).除A型外,其他各型胸腺肿瘤均有复发病例.完整切除病例中,复合组复发率为9.4％ (10/106),单纯组复发率为11.7％(9/77);前者术后5和10年生存率分别是89.3％和81.2％,后者分别是90.0％和78.9％.术后5年,复合组死亡9例,6例死于肌无力危象;单纯组死亡7例,6例为Ⅳ期未切除胸腺瘤和胸腺癌.结论 合并MG对胸腺瘤患者远期疗效影响不大,但MG的存在有利于胸腺瘤的早期诊断及治疗.无论是否合并MG,胸腺瘤手术均应采用胸腺扩大切除.肌无力危象和Ⅳ期胸腺瘤、胸腺癌分别是合并MG胸腺瘤和单纯胸腺瘤的主要死亡原因.     

胸腺瘤与胸腺瘤合并重症肌无力的临床探讨

目的　探讨胸腺瘤 (TT)及胸腺瘤合并重症肌无力 (TTMG)的临床特点。方法　对 2 2年间外科治疗的TT 2 5 8例 ,其中单纯TT 16 8例 (组 1) ,TTMG 90例 (组 2 )的临床特点进行对比分析。结果　组 1平均年龄 38 4岁 ,93 4%的病人肿瘤直径大于 5cm ,病理分期多为III、IV期 (6 1 2 % )。组 2平均年龄 46 2岁 ,肿瘤直径 5cm以下占 6 5 6 % ,5 5 2 %为病理I期。结论　早期胸腺瘤诊断标准为 :肿瘤直径<3cm和病理分期I期 ;TTMG的特征是肌无力 (MG)的症状重、病史短、症状进展快、胸腺危象的发生率高。     

重症肌无力合并胸腺瘤的手术治疗和临床病理分析

目的 探讨重症肌无力（myasthenia gravis，MG）合并胸腺瘤患者的临床病理特点及合理的外科治疗疗案。方法 回顾性分析47例MG合并胸腺瘤患者的临床资料。其胸腺瘤Masaoka病理分型：Ⅰ期22例，Ⅱ期12例，Ⅲ期13例；MG改良Osserman法分型：Ⅰ型20例，Ⅱa型14例，Ⅱb型7例，Ⅲ型6型。采用胸骨正中切口23例，前胸切口19例，后外侧切口15例。以累积生存率、MG转归为指标进行统计分析。结果本组平均随诊76．5（10～178）月。①11例（显性MG10例，隐性MG1例）术后围手术期出现肌无力危象（23．4％）。全组随诊共6例死于MG（12．8％），7例死于胸腺瘤（14．9％）。②显性MG32例，术后随诊5年总完全缓解率达34．4％，总改善率为62．5％。隐性MG15例，发作时间平均为术后37．7（0～137）d，出现MG后的5年自然缓解率为25．0％。③影响MG转归的因素为术后围手术期是否出现危象，出现者MG转归较差（P〈0．05）。④经COX模型预后多因素分析，随诊中MG病情反复且有加重（优势比OR=2．16），胸腺瘤病理分期（OR=2．03）和手术方式（OR=1．63）为影响预后的主要因素。结论 扩大胸腺切除术、术后肿瘤综合治疗、MG的围手术期综合处理及其长期治疗是提高疗效的有效手段。     

胸腺瘤切除术后重症肌无力的临床分析

目的 探讨胸腺瘤切除术后出现重症肌无力(MG)患者的临床病理特点。方法 回顾性分析15例胸腺瘤切除术后出现MG患者的临床资料,并与同时期手术平均随诊5．5年未发现：MG的全部112例单纯胸腺瘤患者的临床资料比较。15例胸腺瘤切除术后出现MG患者中女性9例、男性6例;胸腺瘤Masaoka分期Ⅰ期7例、Ⅱ期4例、Ⅲ期4例;上皮细胞型3例、淋巴细胞型4例、混合型7例、不定1例。平均随诊时间为76．7个月(8～178个月)。结果 (1)胸腺瘤切除术后出现MG的时间为术后麻醉苏醒时至术后137个月(平均33．9个月),MG症状完全缓解时间平均为术后30．9个月(0．5～120个月);(2)麻醉苏醒时即出现：MG的4例患者中,均使用了非去极化肌松剂;(3)术后放射治疗患者中3例出现MG(3／67),出现时间平均为治疗第24天,已照剂量平均为36 Gy;(4)女性、病程较长,混合型,肿瘤较大,病期稍晚者,可能有发生术后MG的倾向。结论 手术、术后放射治疗及麻醉中肌松药选择和剂量控制,均可影响术后MG的发生。     

胸腔镜胸腺切除术治疗重症肌无力500例

目的 总结胸腔镜胸腺切除术治疗重症肌无力(MG)的经验,对比胸腺瘤和非胸腺瘤MG患者的术后效果,分析胸腔镜联合纵隔镜和单纯胸腔镜治疗非胸腺瘤MG的远期效果.方法 2001年至2011年,采用胸腔镜胸腺扩大切除术治疗MG患者500例,根据是否合并胸腺瘤和术中是否联合纵隔镜分组:胸腔镜胸腺瘤组(A组)118例,胸腔镜非胸腺瘤组(B组)301例,胸腔镜联合纵隔镜非胸腺瘤组(C组)81例.结果 全组无术中死亡.完全电视胸腔镜下完成手术495例.A组手术(128.5±77.8) min,术后24.6％患者出现肌无力危象;B组手术(111.3±31.6) min,术后11.0％患者出现肌无力危象;C组手术(145.0 ±71.6) min,术后9.9％患者出现肌无力危象.术后随访3个月至11年,A、B、C组患者完全缓解率(CSR)分别为28.7％、37.3％、36.5％.无病生存曲线示术后3年B、C组CSR高于A组,术后5年C组CSR高于B组.术后第5年C组CSR接近60％,B组为50％,而A组仅为36％.结论 胸腔镜基础上联合纵隔镜胸腺扩大切除手术清除颈部、前纵隔脂肪组织及异位胸腺更为彻底,远期效果更加理想.与非胸腺瘤MG患者相比,胸腺瘤MG患者术后远期效果较差.     

电视胸腔镜治疗胸腺瘤和重症肌无力

目的　探讨电视胸腔镜治疗胸腺肿瘤和重症肌无力 (MG)的手术方法和可行性。方法　1996年 3月至 2 0 0 2年 12月 ,2 2例病人行胸腺瘤和 (或 )重症肌无力胸腔镜手术治疗。其中男 16例 ,女 6例 ;年龄 14～ 77岁 ,平均 44 1岁。行胸腺全切 12例 ,合并MG者行胸腺扩大切除 10例。结果　所有手术均在胸腔镜下完成 ,无中转开胸者。 3例MG病例术后需短暂呼吸机辅助通气 ( <2 4h) ,二次气管插管1例 ,余无严重并发症 ,无手术死亡。平均手术时间 10 8min ,平均胸腔引流 2d ,平均术后住院 4 5d。结论　胸腔镜治疗Ⅰ期胸腺瘤较开胸手术具有创伤小、恢复快等显著优势 ,且符合该类肿瘤的外科治疗原则 ;胸腔镜胸腺扩大切除治疗重症肌无力在技术上是可行的。     

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.     

重症肌无力术后延长拔管时间的临床价值

目的　探讨重症肌无力 (MG)胸腺切除术后 ,延长气管拔管时间 ,减少气管切开的价值。方法　回顾分析 1978年至 2 0 0 2年 12月行MG胸腺切除 2 36例 ,按时间分A组 :1996年 12月以前手术者116例 ,对术后可能发生肌无力危象的高危因素病人施行预防性气管切开 ;B组 :1997年后手术 12 0例 ,对具发生危象高危因素者采用延长气管拔管时间 ,并对两组危象发生率及气管切开率进行比较。结果　全组发生危象 4 4例 (18 6 % ) ,气管切开 4 6例 (ARDS 1例除外 )占 19 5 %。其中A组发生危象 2 3例(19 8% ) ,气管切开 34例 (2 9 3% ) ;B组发生危象 2 1例 (17 5 % ) ,气管切开 12例 (10 % )。两组危象发生率无明显差异 ,但A组的气管切开率明显高于B组 (P <0 0 0 1)。结论　对MG胸腺切除术后具发生危象高危因素病人 ,采用延长气管插管时间及辅助通气 ,可显著减少气管切开率。     

胸腺扩大切除术治疗重症肌无力527例

目的总结胸腺扩大切除术治疗重症肌无力(myasthenia gravis,MG)的外科治疗经验,探讨MG外科治疗效果。方法回顾性分析我院1996年6月至2017年10月期间527例行胸腺扩大切除术的MG患者临床病例资料,其中男242例,女285例;年龄5~77岁,平均(52.6±13.7)岁。病程12天~18年。合并甲状腺功能亢进症22例,纯红细胞再生障碍性贫血7例,甲状腺机能减退症、肠激惹症、风湿性关节炎、强直性脊柱炎和血小板减少综合征各1例。改良OssermanⅠ型272例,Ⅱa型72例,Ⅱb型78例,Ⅲ型81例,Ⅳ型24例。所有患者肌疲劳试验、新斯的明试验阳性,胸部CT检查明确诊断。总结围手术期相关资料及术后随访情况。结果围手术期死亡3例,均为胸腺瘤合并MG,其中OssermanⅢ型MG 2例、Ⅳ型MG 1例。术后肌无力危象15例,其中OssermanⅡb型2例、Ⅲ型11例、Ⅳ型2例,气管切开7例。血浆置换70例,并发低渗综合征、下肢静脉血栓各2例。术后病理诊断胸腺增生293例(55.60%)、胸腺瘤207例(39.28%)、胸腺囊肿24例(4.55%)和胸腺萎缩3例(0.57%)。随访378例,平均随访(85.9±58.5)月;MG完全缓解、部分缓解、无变化和恶化患者分别为135例(35.71%)、192例(50.79%)、41例(10.85%)和10例(2.65%)。完全缓解率OssermanⅠ>Ⅱa>Ⅳ>Ⅱb>Ⅲ型,恶化率OssermanⅢ>Ⅳ>Ⅰ型。OssermanⅠ型外科治疗无效18例,术前病程>5~10年;恶化1例,为应用电视胸腔镜胸腺切除的眼肌型MG患者,遗留胸腺左叶未切除,6年后发展为重度全身型,再次手术切除遗留的左叶胸腺,证实左叶胸腺代偿性肥大增生。恶化患者中死亡6例,均为胸腺瘤合并MG,其中OssermanⅢ型5例、Ⅳ型1例;死亡原因为肌无力危象3例,快速停服溴吡斯的明3个月后突发呼吸骤停猝死2例,胆碱能危象1例。结论规范的胸腺扩大切除是治疗MG的有效方法,眼肌型MG尽早手术可有效降低其全身性转化风险。OssermanⅡb型以上MG易发生肌无力危象,围手术期采取综合处理措施有助于降低MG相关风险。重症术后远期可反复发生肌无力危象,须规律用药,并采取MG综合治疗措施。     

胸腺扩大切除术治疗重症肌无力527例

目的总结胸腺扩大切除术治疗重症肌无力(myasthenia gravis,MG)的外科治疗经验,探讨MG外科治疗效果。方法回顾性分析我院1996年6月至2017年10月期间527例行胸腺扩大切除术的MG患者临床病例资料,其中男242例,女285例;年龄5~77岁,平均(52.6±13.7)岁。病程12天~18年。合并甲状腺功能亢进症22例,纯红细胞再生障碍性贫血7例,甲状腺机能减退症、肠激惹症、风湿性关节炎、强直性脊柱炎和血小板减少综合征各1例。改良OssermanⅠ型272例,Ⅱa型72例,Ⅱb型78例,Ⅲ型81例,Ⅳ型24例。所有患者肌疲劳试验、新斯的明试验阳性,胸部CT检查明确诊断。总结围手术期相关资料及术后随访情况。结果围手术期死亡3例,均为胸腺瘤合并MG,其中OssermanⅢ型MG 2例、Ⅳ型MG 1例。术后肌无力危象15例,其中OssermanⅡb型2例、Ⅲ型11例、Ⅳ型2例,气管切开7例。血浆置换70例,并发低渗综合征、下肢静脉血栓各2例。术后病理诊断胸腺增生293例(55.60%)、胸腺瘤207例(39.28%)、胸腺囊肿24例(4.55%)和胸腺萎缩3例(0.57%)。随访378例,平均随访(85.9±58.5)月;MG完全缓解、部分缓解、无变化和恶化患者分别为135例(35.71%)、192例(50.79%)、41例(10.85%)和10例(2.65%)。完全缓解率OssermanⅠ>Ⅱa>Ⅳ>Ⅱb>Ⅲ型,恶化率OssermanⅢ>Ⅳ>Ⅰ型。OssermanⅠ型外科治疗无效18例,术前病程>5~10年;恶化1例,为应用电视胸腔镜胸腺切除的眼肌型MG患者,遗留胸腺左叶未切除,6年后发展为重度全身型,再次手术切除遗留的左叶胸腺,证实左叶胸腺代偿性肥大增生。恶化患者中死亡6例,均为胸腺瘤合并MG,其中OssermanⅢ型5例、Ⅳ型1例;死亡原因为肌无力危象3例,快速停服溴吡斯的明3个月后突发呼吸骤停猝死2例,胆碱能危象1例。结论规范的胸腺扩大切除是治疗MG的有效方法,眼肌型MG尽早手术可有效降低其全身性转化风险。OssermanⅡb型以上MG易发生肌无力危象,围手术期采取综合处理措施有助于降低MG相关风险。重症术后远期可反复发生肌无力危象,须规律用药,并采取MG综合治疗措施。     

Thymoma is associated with relapse of symptoms after transsternal thymectomy for myasthenia gravis

Thymectomy is considered a therapeutic option for patients with myasthenia gravis. A myasthenic patient who has not received any treatment for years and shows no signs or symptoms of the disease after operation is still susceptible to a recurrence of myasthenic symptoms. To investigate which factors are related to relapse of symptoms in patients having thymectomy, we conduct a retrospective review in the patients who had experienced complete remission after thymectomy. Complete remission was achieved in 92 of 154 patients who received extended transsternal thymectomy for myasthenia gravis. Among these 92 patients, 20 patients had relapse of symptoms and needed medication again after complete remission was achieved (21.7%). Ten of 22 patients in the thymomatous group had relapse of symptom after complete remission was achieved, while only 10 of 70 patients in the nonthymomatous group had relapse of symptom (P=0.006). Multivariate Cox regression analysis revealed that thymoma was an independent factor for the development of relapse of symptoms. In conclusion, thymoma is an adverse prognostic factor for the MG patients who have experienced complete remission after thymectomy. The patients with thymoma had a greater possibility to develop relapse of symptoms than the patients without thymoma.     

Prognostic significance of thymomas in patients with myasthenia gravis

BACKGROUND: The presence of thymoma may be a negative prognostic factor with respect to the outcome of myasthenia gravis (MG). METHODS: Of 122 consecutive patients with MG undergoing thymectomy between August 1994 and September 2000, 37 had a thymoma. Postoperative radiation was administered to all patients with stage II thymoma and higher. To determine differences in presentation and outcome, thymoma patients were compared with patients with atrophic (n = 49) or hyperplastic (n = 36) thymus gland on final pathology. RESULTS: Thymoma patients were significantly older (52 +/- 14 vs 36 +/- 15 years, p < 0.0001) and included a significantly higher proportion of males (54% vs 28%, p = 0.006) than patients without thymoma. However, the preoperative Osserman grade and the duration of symptoms before surgery were not significantly different between groups. Mean follow-up after thymectomy was not significantly different between patients with or without thymoma (32 +/- 23 vs 37 +/- 19 months, respectively, p = 0.3). At last follow-up, the proportion of asymptomatic patients (63% vs 70%, respectively, p = 0.5) and the mean Osserman grade (0.6 +/- 0.9 vs 0.5 +/- 0.9, respectively, p = 0.6) were similar in both groups. In addition, the rate of complete remission reached 36% at 5 years in patients with or without thymoma (p = 0.8). CONCLUSIONS: Although myasthenic patients with thymoma are significantly older and include a greater proportion of males, the overall outcome, including the rate of complete remission, was similar between patients with or without thymoma. Therefore, the presence of a thymoma should not necessarily be viewed as a negative prognostic factor regarding recovery from myasthenia gravis.     

胸腺瘤的诊断、治疗和预后

目的：探讨影响胸腺瘤的诊断,治疗及预后的相关因素。方法：回顾性分析116例胸腺瘤的临床资料,运用寿命表法计算其生存率,以生存,复发或转移率为指标,进行研究。结果：胸部X线等影像学检查是本病诊断的主要手段,重症肌无力是最常见的伴随疾病,发生率为25．0％（29／116）。扩大胸腺及胸腺瘤切除可降低Ⅰ、Ⅱ期肿瘤的复发率（x^2=4.941,P=0.0219),放疗和化疗等综合治疗可以提高疗效。组织学分型（M－H）法与临床分期有明显的相关性,能更有效地反映胸腺瘤的侵袭性(=0.385,P=0.007),本组患者3,5,10年生存率分别为81．2％,67．9％和40．5％,肿瘤分期与生存率明显呈负相关（r=-0.897,P=0.000)。结论：肿瘤的组织类型,病理分期及综合治疗方法是影响患者预后的重要因素,伴随疾病对患者的预后无明显影响。     

横断胸骨扩大胸腺切除治疗全身型重症肌无力

目的探讨经横断胸骨入路行扩大胸腺切除治疗重症肌无力的临床疗效。了解该入路的特点及临床疗效有助于该领域胸外科医师在临床实践中进行更好的临床决策。 方法对1998至2008年在复旦大学附属华山医院胸心外科行横断胸骨治疗全身型重症肌无力的211例患者的临床资料进行回顾性研究,分析患者术中和术后基本情况。并对术后5年进行随访的患者根据是否合并胸腺瘤进行分组,采用χ²检验比较两组间的疗效。 结果经横断胸骨入路能满足对合并Masaoka-Koga Ⅰ期及Ⅱ期胸腺瘤患者及无瘤患者实施扩大胸腺切除的需要,手术并发症较低,便于围术期护理,恢复迅速。对173例患者进行术后5年随访,总缓解率达到79.8%(138/173),无肿瘤复发。合并胸腺瘤组的总缓解率为81.9%(59/72),未合并胸腺瘤组的总缓解率为78.2%(79/101),两组间比较差异无统计学意义(χ²＝0.362,P＝0.548)。 结论与其他常用手术入路相比,横断胸骨入路的特点值得该领域胸外科医师关注。     

"Maximal" thymectomy for myasthenia gravis. Results

Thymectomy has been shown to be effective in the treatment of myasthenia gravis. The logical goal of operation has been complete removal of the thymus, but there has been controversy about the surgical technique and its relation to results. Surgical-anatomic studies have shown gross and microscopic thymus widely distributed in the neck and mediastinum. We believe that an en bloc transcervical-transsternal "maximal" thymectomy is required to remove all thymic tissue predictably. Ninety-five patients with generalized myasthenia gravis underwent "maximal" thymectomy consecutively between 1977 and 1985 and were evaluated 6 months to 89 months after operation. In Group A (N = 72), myasthenia gravis without thymoma, the uncorrected data revealed that 96% (69) had benefited from operation: 79% (57) had no symptoms; 46% (33) were in remission; 33% (24) were symptom free when receiving minimal doses of pyridostigmine; and none were worse. Life table analysis yielded a remission rate of 81% at 89 months. In group B (N = 8), myasthenia gravis without thymoma for which patients underwent reexploration for incapacitating weakness after earlier transcervical or transsternal operations, residual thymus was found in all. One patient was in remission, two were symptom free when receiving medication, one was unchanged, and none were worse. In group C (N 15), myasthenia gravis and thymoma, two patients were in remission and nine were symptom free when receiving medication. Two patients in this group died 2 and 4 years postoperatively in crisis. Response to thymectomy in group A was greater in patients with mild myasthenia gravis and may have been better in patients who had symptoms for less than 60 months preoperatively, but the response did not depend on age, sex, presence or absence of thymic hyperplasia or involution, or titers of acetylcholine receptor antibodies. The response to thymectomy in group B was striking but slower than in group A, perhaps because symptoms were more severe and of longer duration. The response in group C was also less good than in group A and proportionately fewer benefited. These results support the recommendation for thymectomy in the treatment of patients with generalized myasthenia gravis and indicate the desirability of a maximal procedure. For persistent or recurrent severe symptoms after previous transcervical or submaximal transsternal resections, reoperation by this technique is also recommended.     

Myasthenia gravis in elderly patients

The clinical features and the effect of thymectomy were compared between 27 elderly patients (Group 2) and 119 young adult patients (Group 1) with myasthenia gravis (MG). In the elderly group, MG was type I in 3 patients, type IIA in 6, type IIB in 17, and type III in 1; and in the young group, type I in 6, type IIA in 36, type IIB in 73, and type III in 4. The association rate with autoimmune disease in patients without thymoma was 12.5% (1/8) in Group 2 and 21.3% (20/94) in Group 1. Autoimmune diseases were not seen in any patients with thymoma. The clinical stage of thymoma was not significantly different between the two groups. The rates of remission and of palliation at 3 years after thymectomy were 18.2% and 72.7%, respectively, in Group 2 patients with thymoma, 21.4% and 78.6% in Group 1 patients with thymoma, 50% and 100% in Group 2 patients without thymoma, and 50% and 98.1% in Group 1 patients without thymoma.     

外科治疗重症肌无力的疗效分析

目的评价外科治疗重症肌无力的效果,探讨影响术后肌无力危象发生的因素以及预防治疗要点。方法回顾性分析1985年6月至2005年6月78例接受外科治疗重症肌无力患者的临床资料,对影响术后肌无力危象发生及程度的因素进行分析,比较不同围手术期处理方案的疗效差异。结果肌无力症状完全缓解21例,明显改善38例,改善11例,无变化8例。病程长短、血清抗乙酰胆碱受体抗体水平、Osserman分期和胸腺病理类型均是术后肌无力危象发生的独立相关危险因素。在围手术期处理方面,新方案疗效明显优于旧方案。结论外科治疗重症肌无力具有良好的效果和可行性。     

Clinical and pathologic predictors of outcome in thymoma-associated myasthenia gravis

BACKGROUND: Myasthenia gravis is by far the most common paraneoplastic syndrome of thymomas. There is little information regarding the influence of clinical variables and thymoma-associated factors on biologic development of myasthenia gravis. The aim of the study was to determine independent predictors of clinical outcome in thymoma with myasthenia gravis. METHODS: We studied 108 patients with thymoma-associated myasthenia gravis undergoing removal of the mediastinal mass between 1967 and 2000. Clinical and pathologic variables associated with clinical outcome of myasthenia were assessed by multivariate Cox regression analysis. RESULTS: Patients were followed for a mean period of 10 years (9 months to 33 years). A total of 38 patients died (35.2%), in 14 cases (37%) because of myasthenia gravis and in 6 (16%) because of recurrence of thymoma. With respect to clinical outcome of myasthenia gravis, at the end of the follow-up period, the rate of remission was 16% (n = 17). Of the 91 patients in whom remission was not achieved, 55 had no symptoms with immunosuppressive medication and 36 had symptoms with medication. CONCLUSIONS: In patients with thymoma-associated myasthenia gravis, well-differentiated thymic carcinoma (Müller-Hermelink system), age more than 55 years, and interval from the onset of symptoms to thymectomy of less than 1 year were found to be independent predictors of nonremission of myasthenia gravis after thymectomy.     

Flow cytometric study of lymphocytes associated with thymoma and other thymic tumors

BACKGROUND. A large number of immature T lymphocytes in thymoma may reflect the biological function of the neoplastic epithelial cells. However, to confirm that this lymphocyte-inducing activity is unique to thymoma, lymphocytes associated with other thymic tumors need to be studied. MATERIALS AND METHODS. We used flow cytometry to study lymphocytes recovered from various thymic tumors (65 thymomas, 24 with myasthenia gravis; 5 thymic cancers; 5 germ cell tumors including 3 needle biopsy samples; and 2 other tumors) and results were analyzed in reference to those from 36 normal thymuses. RESULTS. The frequency of CD4(+)CD8(+) (DP) thymocytes in the normal thymus declined with age (0.9-94%, r = -0.83, P < 0.001) reflecting the physiological involution. Association of lymphocytes with this DP phenotype was unique to thymoma: 61 of 65 thymomas but none of the other thymic tumors had more than 3% DP cells (frequency of DP cells; thymoma without MG, 59.5 +/- 31.4%; thymoma with MG, 59.4 +/- 22.1%; and other thymic tumors, 0.8 +/- 1.0; mean +/- SD). All the thymic tumors associated with myasthenia gravis were thymomas and had more than 18% DP cells. CONCLUSION. The presence of DP cells in thymomas but not in other tumors suggests that DP cells are induced by the epithelial cells of thymoma. This characteristic may help diagnose thymic tumors; the presence of more than 3% DP cells suggests a thymoma. Also, association of myasthenia gravis suggests a thymoma.     

Different Characteristics of Thymomas With and Without Myasthenia Gravis

Background  

The objective of this study was to evaluate the different pathological and clinical characteristics of thymomas with and without myasthenia gravis (MG) and to determine whether the presence of MG influences the prognosis in thymoma patients.