title: Surgical strategy in grade II astrocytoma: a population-based analysis of survival and morbidity with a strategy of early resection as compared to watchful waiting.
abstract: BACKGROUND
  We recently demonstrated a survival benefit of early resection in unselected diffuse low-grade gliomas (LGG). However, heterogeneity within the LGG entity warrants investigation in a homogenous subgroup. Astrocytoma represents the largest subgroup of LGG, and is characterized by diffuse growth and inferior prognosis. We aimed to study the effects of early resection compared to biopsy and watchful waiting in this subgroup.
  
  
  METHODS
  Patient data was retrospectively reviewed in two neurosurgical departments with regional referral practice. In one hospital, initial diagnostic biopsies and watchful waiting was favored, while early resections guided with three-dimensional (3D) ultrasound were advocated in the other hospital. This created a natural experiment with patient management heavy influenced by residential address. In the hospitals' histopathology databases, all adult patients diagnosed with supratentorial LGG from 1998 through 2009 were screened (n = 169) and underwent blinded histopathological review. Histopathological review concluded with 117 patients with grade II astrocytomas that were included in the present study. The primary end-point was overall survival assessed by a regional comparison.
  
  
  RESULTS
  Early resections were performed in 51 (82 %) versus 12 (22 %) patients in the respective hospitals (p < 0.001). The two patient populations were otherwise similar. Median survival was 9.7 years (95 % CI 7.5-11.9) if treated in the hospital favoring early resections compared to 5.6 years (95 % CI 3.5-7.6) if treated at the hospital favoring biopsy and watchful waiting (p = 0.047). No difference in surgical-related neurological morbidity was seen (p = 0.843).
  
  
  CONCLUSIONS
  Early 3D ultrasound guided resections improve survival, apparently without increased morbidity, compared to biopsy and watchful waiting in patients with diffuse World Health Organization (WHO) grade II astrocytomas.
authors.affiliation: Department of Neurosurgery, St.Olavs University Hospital, N-7006, Trondheim, Norway, asgeir.s.jakola@ntnu.no.
authors.forename: Asgeir Store
authors.initials: AS
authors.lastname: Jakola
authors.forename: Geirmund
authors.initials: G
authors.lastname: Unsgård
authors.forename: Kristin Smistad
authors.initials: KS
authors.lastname: Myrmel
authors.forename: Roar
authors.initials: R
authors.lastname: Kloster
authors.forename: Sverre Helge
authors.initials: SH
authors.lastname: Torp
authors.forename: Ole Kristian
authors.initials: OK
authors.lastname: Losvik
authors.forename: Sigurd
authors.initials: S
authors.lastname: Lindal
authors.forename: Ole
authors.initials: O
authors.lastname: Solheim
mesh_terms: D001254:Astrocytoma / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D001706:Biopsy; D001932:Brain Neoplasms / Q000401:mortality / Q000473:pathology / Q000601:surgery*; D018479:Early Intervention, Educational; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods; D016343:Monitoring, Intraoperative / Q000379:methods; D038361:Neuronavigation / Q000379:methods; D019635:Neurosurgical Procedures / Q000379:methods; D012189:Retrospective Studies; D016896:Treatment Outcome; D057832:Watchful Waiting