title: The role of Gamma Knife radiosurgery in the management of cavernous sinus meningiomas.
abstract: OBJECTIVE
  To evaluate the efficacy of Gamma Knife (GK) radiosurgery in terms of neurologic improvement and tumor growth control (TGC) in a large series of patients with cavernous sinus meningioma (CSM).
  
  
  METHODS
  One hundred thirty-eight patients with CSM (28 males, 110 females; mean age: 56.2 years) were treated with GK between February 1993 and February 2001. GK was used as a first-choice treatment in 68/138 patients and as postoperative adjuvant therapy in 70/138. In 32 patients, it was possible to compare the size of the planned treatment volume to tumor volume using the conformity index (CI); optimal CI values were taken to be < or =1.5 (range: 0.94-2.24).
  
  
  RESULTS
  A follow-up (FU) period of at least 12 months was available for 111 patients (median: 48.2 months, range: 12.1-84.5 months). Clinical conditions were improved or stable in 107/111 patients (96.5%). Neurologic recovery was observed in 76% of cases treated by GK alone and in 56.5% of adjuvant treatments (p < 0.03). Adequate TGC was documented in 108/111 tumors (97%), with shrinkage/disappearance in 70/111 (63%) and no variation in volume in 38/111 (34%); the overall actuarial progression-free survival rate at 5 years was 96%. Tumor size regression was observed in 79.5% of patients with FU >30 months, compared with 47.5% of patients with FU <30 months (p < 0.001). One hundred percent TGC was shown in treated patients with a CI < or =1.5 (20/32), compared with 92% TGC in cases with a CI >1.5 (p < 0.15, NS). Radiosurgical sequelae were transient in 4/111 cases (3.5%) and permanent in one case (1%).
  
  
  CONCLUSIONS
  For the FU period of our series (median: >4 years), GK radiosurgery seems to be both safe (permanent morbidity 1%) and effective (96% neurologic improvement/stability, 97% overall TGC, 96% actuarial TGC at 5 years) and might be considered as a first-choice treatment for selected patients with CSM.
authors.affiliation: Department of Neurosurgery, University Hospital, Verona, Italy. antonio.nicolato@mail.azosp.vr.it
authors.forename: Antonio
authors.initials: A
authors.lastname: Nicolato
authors.forename: Roberto
authors.initials: R
authors.lastname: Foroni
authors.forename: Franco
authors.initials: F
authors.lastname: Alessandrini
authors.forename: Sergio
authors.initials: S
authors.lastname: Maluta
authors.forename: Albino
authors.initials: A
authors.lastname: Bricolo
authors.forename: Massimo
authors.initials: M
authors.lastname: Gerosa
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001921:Brain / Q000473:pathology; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D008297:Male; D008577:Meningeal Neoplasms / Q000601:surgery*; D008579:Meningioma / Q000601:surgery*; D008875:Middle Aged; D016634:Radiosurgery / Q000379:methods*; D013997:Time Factors; D016896:Treatment Outcome