title: Thymic carcinoma patients with myasthenia gravis exhibit better prognoses.
abstract: BACKGROUND
  Thymic carcinoma is an aggressive mediastinal neoplasm with a poor prognosis, but the factors that contribute to its prognosis are not completely understood. Myasthenia gravis (MG) can coexist with thymic carcinoma with low incidence, but the effect MG has on thymic carcinoma prognosis is unknown. Here, we investigated the prognostic factors of thymic carcinoma and the influence of MG on patients with this disease.
  
  
  METHODS
  Between January 1996 and December 2012, 49 patients were diagnosed with thymic carcinoma and surgically treated at our institution. Clinical data and survival information were recorded and systematically reviewed. Kaplan-Meier survival curves were generated, and independent prognostic factors were identified by Cox's proportional hazard model.
  
  
  RESULTS
  Complete resection was achieved in 30 patients (61.2 %), and incomplete resection was performed on the other 19 patients (38.8 %). Six of the 49 patients with thymic carcinoma also presented with MG (12.2 %). Interestingly, these 6 patients exhibited much better prognoses when compared to the other 43 patients. Patients with MG also had significantly smaller tumors (P = 0.045), earlier Masaoka stage (P = 0.048), and higher complete resection rates (P = 0.042). However, multivariate analysis demonstrated that complete resection was the only independent predictor for overall survival (OS) (P < 0.001).
  
  
  CONCLUSIONS
  The OS of patients with thymic carcinoma depends on complete resection, but patients with MG also demonstrate improved prognoses. MG patients have higher rates of complete surgical resection, which may account for their better prognoses. Patients with MG have unique features that may aid in the clinical management of these patients.
authors.affiliation: Department of Thoracic Surgery, The First Affiliated Hospital of China Medical University, No. 155 North Nanjing Street, Shenyang, 110001, Liaoning Province, China.
authors.forename: Wenya
authors.initials: W
authors.lastname: Li
authors.affiliation: Department of Surgical Oncology and General Surgery, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning Province, China.
authors.forename: Zhifeng
authors.initials: Z
authors.lastname: Miao
authors.affiliation: Department of Rheumatology and Immunology, The First Affiliated Hospital of China Medical University, Shenyang, 110001, Liaoning Province, China.
authors.forename: Xudong
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Thoracic Surgery, The First Affiliated Hospital of China Medical University, No. 155 North Nanjing Street, Shenyang, 110001, Liaoning Province, China.
authors.forename: Qigang
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Thoracic Surgery, The First Affiliated Hospital of China Medical University, No. 155 North Nanjing Street, Shenyang, 110001, Liaoning Province, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Sun
authors.affiliation: Department of Thoracic Surgery, The First Affiliated Hospital of China Medical University, No. 155 North Nanjing Street, Shenyang, 110001, Liaoning Province, China.
authors.forename: Peiwen
authors.initials: P
authors.lastname: Li
authors.affiliation: Department of Thoracic Surgery, The First Affiliated Hospital of China Medical University, No. 155 North Nanjing Street, Shenyang, 110001, Liaoning Province, China.
authors.forename: Wenke
authors.initials: W
authors.lastname: Liu
authors.affiliation: Department of Thoracic Surgery, The First Affiliated Hospital of China Medical University, No. 155 North Nanjing Street, Shenyang, 110001, Liaoning Province, China. 41578203@qq.com.
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009157:Myasthenia Gravis / Q000150:complications*; D011379:Prognosis; D016016:Proportional Hazards Models; D012189:Retrospective Studies; D013953:Thymus Neoplasms / Q000401:mortality*
keywords: Complete resection; Myasthenia gravis; Prognosis; Thymic carcinoma