title: Tumor recurrence and survival in patients treated for thymomas and thymic squamous cell carcinomas: a retrospective analysis.
abstract: OBJECTIVE
  Thymic epithelial tumors (TET) are rare epithelial neoplasms of the thymus with considerable histologic heterogeneity. This retrospective study focused on the correlation of WHO-defined TET histotypes with survival and tumor recurrence in a large cohort of patients receiving different modes of treatment.
  
  
  METHODS
  Two hundred twenty-eight patients were followed for up to 21 years (median, 60 months; range, 1 to 252 months) after primary surgery. Forty-two patients received adjuvant radiotherapy (mean dose, 53 Gy), and 33 patients received adjuvant chemotherapy.
  
  
  RESULTS
  Seventy-six (88%) of 86 patients with WHO type A, AB, and B1 thymomas were treated by surgery alone, with three tumor relapses after 3 to 10 years (median, 3.4 years). Twelve of 67 patients with WHO type B2 and B3 thymomas in Masaoka stages I and II were treated by adjuvant radiotherapy without evidence of tumor recurrence after 1 to 12 years (median, 4 years). Among 75 patients with B2 and B3 thymomas with incomplete resection or a tumor stage III or higher, the recurrence rate was 34% (n = 23) after 0.5 to 17 years (median, 5 years) in patients receiving adjuvant radiochemotherapy, compared to 78% (seven of nine patients) in patients without adjuvant radiochemotherapy. Incomplete tumor resection was associated with a high recurrence rate (65%) and a poor prognosis (P <.01).
  
  
  CONCLUSIONS
  The long-term outcome of TET patients is related to tumor stage, WHO histotype, completeness of surgical removal, and type of treatment. Prospective trials are warranted to formally address the efficacy of adjuvant therapy in the treatment of localized and advanced malignant TETs.
authors.affiliation: Institute of Pathology, University of Würzburg, Josef-Schneider-Strasse 2, D-97080 Würzburg, Germany. path036@mail.uni-wuerzburg.de
authors.forename: Philipp
authors.initials: P
authors.lastname: Ströbel
authors.forename: Andrea
authors.initials: A
authors.lastname: Bauer
authors.forename: Bernhard
authors.initials: B
authors.lastname: Puppe
authors.forename: Til
authors.initials: T
authors.lastname: Kraushaar
authors.forename: Axel
authors.initials: A
authors.lastname: Krein
authors.forename: Klaus
authors.initials: K
authors.lastname: Toyka
authors.forename: Ralf
authors.initials: R
authors.lastname: Gold
authors.forename: Michael
authors.initials: M
authors.lastname: Semik
authors.forename: Reinhard
authors.initials: R
authors.lastname: Kiefer
authors.forename: Wilfred
authors.initials: W
authors.lastname: Nix
authors.forename: Berthold
authors.initials: B
authors.lastname: Schalke
authors.forename: Hans Konrad
authors.initials: HK
authors.lastname: Müller-Hermelink
authors.forename: Alexander
authors.initials: A
authors.lastname: Marx
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000401:mortality / Q000473:pathology*; D005500:Follow-Up Studies; D006801:Humans; D009364:Neoplasm Recurrence, Local / Q000401:mortality / Q000473:pathology*; D012189:Retrospective Studies; D015996:Survival Rate; D013945:Thymoma / Q000401:mortality / Q000473:pathology* / Q000628:therapy; D013953:Thymus Neoplasms / Q000401:mortality / Q000473:pathology* / Q000628:therapy