title: Pathological Findings in Myasthenia Gravis Patients with Thymic Hyperplasia and Thymoma.
abstract: Thymectomy is routinely carried out in patients with myasthenia gravis (MG) and thymomas. However, there is still a dispute as to whether MG patients with thymic hyperplasia should undergo thymectomy. We aimed to investigate the pathological findings in the thymus in patients with co-existing MG and thymic hyperplasia or thymomas treated with thymectomy, as well as effects of immunosuppression. Thirty-three patients with MG were selected and grouped accordingly: patients with no thymic abnormalities, patients with thymic hyperplasia, and patients with thymomas. All patients were treated with methylprednisolone alongside immunosuppression. A separate cohort of 24 MG patients with thymic hyperplasia or thymomas and treated with thymectomy were selected. As controls, 5 patients with thymomas or thymic carcinoma without MG were selected. Expression of CD5, extracellular regulated protein kinases1/2 mitogen activated protein kinase (ERK1/2MAPKs) and CD95 ligand (FasL) in the thymus was examined. Methylprednisolone and immunosuppressive therapy are highly effective in MG patients with normal thymus tissue and MG patients with thymic hyperplasia compared to MG patients with thymomas alone. CD5 expression was highest in MG patients with thymic hyperplasia, correlating with expression of ERK1/2MAPKs. FasL expression was similar across all groups. Thymomas may be distinguished from thymic hyperplasia by expression of CD5 and ERK1/2MAPKs. Thymectomy is the preferred treatment for MG patients with thymomas but may not be necessary in MG patients with thymic hyperplasia who are treated with immunosuppressive therapy.
authors.affiliation: Department of Neurology, Xijing Hospital, Fourth Military Medical University, No. 169, Changle West Road, Xi'an, 710032, China.
authors.forename: Ping
authors.initials: P
authors.lastname: Chen
authors.affiliation: Department of Neurology, Beijing Aerospace General Hospital, Beijing, 100076, China.
authors.forename: Ying-Peng
authors.initials: YP
authors.lastname: Wang
authors.affiliation: Department of Infectious disease, Beijing You'an Hospital, Capital Medical University, Beijing, 100075, China.
authors.forename: Dan-Lei
authors.initials: DL
authors.lastname: Mou
authors.affiliation: Department of Neurology, First Affiliated Hospital of Medical College, Xi'an Jiao Tong University, Xi'an, 710061, China.
authors.forename: Zheng-Yi
authors.initials: ZY
authors.lastname: Li
authors.affiliation: Department of Neurology, First Affiliated Hospital of Medical College, Xi'an Jiao Tong University, Xi'an, 710061, China.
authors.forename: Qiu-Min
authors.initials: QM
authors.lastname: Qu
authors.affiliation: Department of Pathology, First Affiliated Hospital of Medical College, Xi'an Jiao Tong University, Xi'an, 710061, China.
authors.forename: Hong-Yan
authors.initials: HY
authors.lastname: Wang
authors.affiliation: Department of Pathology, First Affiliated Hospital of Medical College, Xi'an Jiao Tong University, Xi'an, 710061, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Deng
authors.affiliation: Department of Pathology, First Affiliated Hospital of Medical College, Xi'an Jiao Tong University, Xi'an, 710061, China.
authors.forename: Xiao-Feng
authors.initials: XF
authors.lastname: Li
authors.affiliation: Department of Neurology, Xijing Hospital, Fourth Military Medical University, No. 169, Changle West Road, Xi'an, 710032, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Wang
authors.affiliation: Department of Neurology, Federal Ministry of Health Beijing Hospital, No. 1, Dahua Road, Beijing, 100730, China. xuxianhao99@aliyun.com.
authors.forename: Xian-Hao
authors.initials: XH
authors.lastname: Xu
authors.affiliation: Department of Neurology, Xijing Hospital, Fourth Military Medical University, No. 169, Changle West Road, Xi'an, 710032, China. zhaogang@fmmu.edu.cn.
authors.forename: Gang
authors.initials: G
authors.lastname: Zhao
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D014408:Biomarkers, Tumor / Q000378:metabolism*; D016022:Case-Control Studies; D002648:Child; D053222:Fas Ligand Protein / Q000378:metabolism; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D000074001:Intercellular Adhesion Molecule-3 / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D019950:Mitogen-Activated Protein Kinase 1 / Q000378:metabolism; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D009157:Myasthenia Gravis / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D011379:Prognosis; D012189:Retrospective Studies; D013945:Thymoma / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D013952:Thymus Hyperplasia / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D013953:Thymus Neoplasms / Q000188:drug therapy / Q000378:metabolism / Q000473:pathology*; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; C505661:FASLG protein, human; D053222:Fas Ligand Protein; D007166:Immunosuppressive Agents; D000074001:Intercellular Adhesion Molecule-3; C535150:MAPK1 protein, human; D019950:Mitogen-Activated Protein Kinase 1; D048052:Mitogen-Activated Protein Kinase 3
keywords: Myasthenia gravis; Thymectomy; Thymic hyperplasia; Thymoma