Nabe Yusuke, Hashimoto Teppei, Tanaka Kanji, Fujita Yasuhiro, Yoshimatsu Katsuma, Nemoto Yukiko, Oyama Rintaro, Matsumiya Hiroki, Mori Masataka, Kanayama Masatoshi, Taira Akihiro, Shinohara Shinji, Kuwata Taiji, Takenaka Masaru, Tashima Yuko, Kuroda Koji, Tanaka Fumihiro
Second Department of Surgery, School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
Gland Surg. 2021 Aug;10(8):2408-2413. doi: 10.21037/gs-21-287.
Approximately 15-29.6% of patients with thymoma have myasthenia gravis (MG). Some of these patients develop MG after thymectomy despite having no history of MG or related symptoms. Few previous studies have examined the risk factors for the development of post-thymectomy MG in patients with thymoma. Herein, we retrospectively reviewed our institutional experience with patients with thymoma who developed MG after thymectomy.
Twenty-six patients with thymoma but without MG, who were tested preoperatively for anti-acetylcholine receptor antibody (anti-AChR-Ab) levels, underwent surgical resection at our hospital between 2013 and 2020. Patients with thymic carcinoma were excluded from the study. We evaluated the association of outcomes with preoperative anti-AChR-Ab levels and post-thymectomy MG. We performed a χ test for bivariate analysis of categorical data. Differences were considered significant at P<0.05.
The characteristics of the 26 patients (median age: 62 years; 8 men, 18 women) were as follows: World Health Organization (WHO) classifications AB (n=8), B1 (n=9), B2 (n=6), B3 (n=1), and others (n=2) and Masaoka stage I (n=12), II (n=9), III (n=3), and IVa (n=2). Among the 26 patients, only five had high (>0.3 nmol/L) preoperative anti-AChR-Ab levels. Post-thymectomy MG occurred in two of the five patients (40%) with high preoperative anti-AChR-Ab levels. A high preoperative serum anti-AChR-Ab titer was significantly associated with post-thymectomy MG (P=0.0267). The anti-AChR-Ab titer was also measured postoperatively in four of the five (80%) patients with high preoperative levels. The anti-AChR-Ab titer decreased in two of these four patients, and neither developed postoperative MG.
Preoperative and postoperative anti-AChR-Ab positivity might be associated with post-thymectomy MG. Therefore, regular measurement of anti-AChR-Ab levels after thymectomy is required.
约15%-29.6%的胸腺瘤患者合并重症肌无力（MG）。其中一些患者在胸腺切除术后出现MG，尽管术前并无MG病史或相关症状。此前很少有研究探讨胸腺瘤患者胸腺切除术后发生MG的危险因素。在此，我们回顾性分析了我院胸腺切除术后发生MG的胸腺瘤患者的情况。
2013年至2020年间，我院对26例无MG的胸腺瘤患者进行了手术切除，术前检测了抗乙酰胆碱受体抗体（抗AChR-Ab）水平。胸腺癌患者被排除在研究之外。我们评估了术前抗AChR-Ab水平与胸腺切除术后MG之间的相关性。我们对分类数据进行双变量分析，采用χ检验。P<0.05时差异具有统计学意义。
26例患者（中位年龄：62岁；男性8例，女性18例）的特征如下：世界卫生组织（WHO）分类AB型（n=8）、B1型（n=9）、B2型（n=6）、B3型（n=1）及其他类型（n=2），Masaoka分期I期（n=12）、II期（n=9）、III期（n=3）及IVa期（n=2）。26例患者中，仅5例术前抗AChR-Ab水平较高（>0.3 nmol/L）。术前抗AChR-Ab水平较高的5例患者中有2例（40%）在胸腺切除术后发生MG。术前血清抗AChR-Ab高滴度与胸腺切除术后MG显著相关（P=0.0267）。术前抗AChR-Ab水平较高的5例患者中有4例（80%）术后也检测了抗AChR-Ab滴度。这4例患者中有2例抗AChR-Ab滴度下降，且均未发生术后MG。
术前及术后抗AChR-Ab阳性可能与胸腺切除术后MG有关。因此，胸腺切除术后需要定期检测抗AChR-Ab水平。
