title: Fractionated stereotactic radiotherapy for acoustic neuromas: a prospective monocenter study of about 158 cases.
abstract: OBJECTIVE
  To evaluate long-term outcomes and efficacy of fractionated stereotactic radiotherapy in the treatment of acoustic neuromas.
  
  
  METHODS
  Between January 1996 and December 2009, 158 acoustic neuromas were treated by FSR in 155 patients. They received a dose of 50.4 Gy, with a safety margin of 1-2mm with a median tumor volume at 2.45 mL (range: 0.17-12.5 mL) and a median follow-up duration at 60 months (range: 24-192).
  
  
  RESULTS
  FSR was well tolerated in all patients with mild sequelae consisting in radiation-induced trigeminal nerve impairments (3.2%), Grade 2 facial neuropathies (2.5%), new or aggravated tinnitus (2.1%) and VP shunting (2.5%). The treatment failed in four patients (2.5%) who had subsequent surgery respectively at 20, 38, 45 and 84 months post-FSR. The local tumor control rates were respectively 99.3%, 97.5% and 95.2% at 3, 5 and >7-year of follow-up. For initial Gardner-Robertson Grade 1 and 2 ANs, the preservation of useful hearing was possible in 54% of the cases; only Grade 1 ANs had stabilized during the course of the follow-up with 71% >7 years. However, hearing preservation was not correlated to the initial Koos Stage and to the radiation dose delivered to the cochlea. Tinnitus (70%), vertigo (59%), imbalance (46%) and ear mastoid pain (43%) had greatly improved post-FRS in most patients. Tumor control, hearing preservation and FRS toxicity were quite similar in patients with NF2, cystic acoustic neuroma, prior surgical resection and Koos Stage 4 AN. No secondary tumors were observed.
  
  
  CONCLUSIONS
  FSR is a safe and effective therapeutic for acoustic neuromas and could be an alternative to microsurgery. Compared to radiosurgery, there are no contraindications for fractioned doses of stereotactic radiotherapy especially for Stage-4 tumors and patients at high risk of hearing loss.
authors.affiliation: Hôpital Maison Blanche, Reims Cedex, France. flitre@chu-reims.fr
authors.forename: Fabien
authors.initials: F
authors.lastname: Litre
authors.forename: Pascal
authors.initials: P
authors.lastname: Rousseaux
authors.forename: Nicolas
authors.initials: N
authors.lastname: Jovenin
authors.forename: Arnaud
authors.initials: A
authors.lastname: Bazin
authors.forename: Philippe
authors.initials: P
authors.lastname: Peruzzi
authors.forename: Didier
authors.initials: D
authors.lastname: Wdowczyk
authors.forename: Philippe
authors.initials: P
authors.lastname: Colin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D019583:Dose Fractionation, Radiation; D005154:Facial Nerve / Q000528:radiation effects; D005260:Female; D006309:Hearing / Q000528:radiation effects; D006801:Humans; D008297:Male; D008875:Middle Aged; D009464:Neuroma, Acoustic / Q000601:surgery*; D011446:Prospective Studies; D016634:Radiosurgery / Q000009:adverse effects / Q000379:methods*; D014012:Tinnitus / Q000209:etiology; D014276:Trigeminal Nerve / Q000528:radiation effects