title: Long-term surgical outcome and biological prognostic factors in patients with skull base meningiomas.
abstract: OBJECTIVE
  Although gross-total resection (GTR) is a preferable treatment for skull base meningiomas, subtotal resection (STR) with or without radiation therapy can be considered as an alternative treatment for patients at considerable surgical risk. The long-term prognosis of such patients might be related to the biological activity of the tumor. This study examined predictors of progression-free survival (PFS) and sought to determine the optimal treatment strategies, focusing on the pathobiological findings of skull base meningiomas.
  
  
  METHODS
  This study included 281 patients with skull base meningiomas (mean follow-up period 88.4 months). Risk factors for tumor progression were examined using a multivariate analysis. The PFS and overall survival (OS) rates were evaluated using the Kaplan-Meier method. The functional outcomes of the patients were measured using the Karnofsky Performance Scale (KPS).
  
  
  RESULTS
  The 10-year PFS and OS rates were 66.4% and 97.4%, respectively. Overall, 83.3% of patients achieved a favorable outcome, that is, an improved or unchanged KPS score. The extent of resection, additional radiotherapy, histological grade, MIB-1 index, and p53-positive rate were significantly associated with PFS. The PFS of patients undergoing STR without radiation therapy was significantly shorter than that of either those undergoing STR with radiation therapy or GTR, while no statistical difference was observed between the latter 2 groups. Among the patients undergoing STR with pathobiological risk factors (histological grade, MIB-1 index, and p53-positive rate), the PFS of the patients who received radiation therapy was better than that of those who did not receive radiation therapy. Among the patients undergoing STR without such risk factors, the PFS was not significantly different between patients who received radiation therapy and those who did not.
  
  
  CONCLUSIONS
  For patients with skull base meningiomas, a GTR is desirable and additional radiation therapy after STR may contribute to a longer PFS. Additional radiation therapy should be recommended, especially for patients with pathobiological risk factors, but not necessarily for those without such risks.
authors.affiliation: Department of Neurosurgery, Keio University School of Medicine, Tokyo, Japan. shigeo.ohba@gmail.com
authors.forename: Shigeo
authors.initials: S
authors.lastname: Ohba
authors.forename: Masahito
authors.initials: M
authors.lastname: Kobayashi
authors.forename: Takashi
authors.initials: T
authors.lastname: Horiguchi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Onozuka
authors.forename: Kazunari
authors.initials: K
authors.lastname: Yoshida
authors.forename: Takayuki
authors.initials: T
authors.lastname: Ohira
authors.forename: Takeshi
authors.initials: T
authors.lastname: Kawase
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis*; D002648:Child; D003131:Combined Modality Therapy; D018572:Disease-Free Survival; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted; D019394:Ki-67 Antigen / Q000032:analysis; D008279:Magnetic Resonance Imaging; D008297:Male; D008577:Meningeal Neoplasms / Q000175:diagnosis / Q000401:mortality / Q000532:radiotherapy / Q000601:surgery*; D008579:Meningioma / Q000175:diagnosis / Q000401:mortality / Q000532:radiotherapy / Q000601:surgery*; D008875:Middle Aged; D018365:Neoplasm, Residual / Q000175:diagnosis / Q000209:etiology* / Q000401:mortality / Q000532:radiotherapy; D011183:Postoperative Complications / Q000209:etiology* / Q000401:mortality; D011379:Prognosis; D018714:Radiotherapy, Adjuvant; D019292:Skull Base Neoplasms / Q000175:diagnosis / Q000401:mortality / Q000532:radiotherapy / Q000601:surgery*; D014057:Tomography, X-Ray Computed; D016159:Tumor Suppressor Protein p53 / Q000032:analysis*; D044767:Ubiquitin-Protein Ligases / Q000032:analysis*; D055815:Young Adult
chemical_list: D014408:Biomarkers, Tumor; D019394:Ki-67 Antigen; D016159:Tumor Suppressor Protein p53; C513496:MIB1 ligase, human; D044767:Ubiquitin-Protein Ligases