title: Age as an independent prognostic factor in patients with glioblastoma: a Radiation Therapy Oncology Group and American College of Surgeons National Cancer Data Base comparison.
abstract: Glioblastoma (GBM) is rare in early adulthood and little information is available on this subgroup. We investigated whether young age (18-30 years) had an independent effect on survival. We retrospectively reviewed patients from two large databases: Radiation Therapy Oncology Group (RTOG) and American College of Surgeons National Cancer Data Base (NCDB). In the RTOG evaluation, we analyzed all eligible GBM cases from 17 RTOG studies from 1974 to 2002. All patients with GBM during 1985-1998 in the NCDB were examined for comparison. Patients were divided into three cohorts: ages 18-30, 31-49, and ≥50. Overall survival, as a function of age (discreet and continuous), was assessed. The RTOG review included 3,136 patients: 112 (3.6%) were 18-30, 780 (24.9%) were 31-49, and 2,244 (71.6%) were ≥50. The median survival times of the three groups were 21.0, 13.5, and 9.1 months (P < 0.0001). Significant improvement in survival for younger patients was demonstrated with adjustment for recursive partitioning analysis (RPA) class. Of the 37,260 patients analyzed in the NCDB, 796 (2.1%) were 18-30, 5,711 (15.3%) were 31-49, and 30,753 (82.5%) were ≥50. The median survival times of the three groups were 18.0, 12.8, and 6.3 months (P < 0.0001). Data were not available for RPA class from this series. GBM is rare in young adulthood, comprising 2.1-3.6% of our patients. They have superior survival, even when adjusted for RPA class. More investigations on the unique biologic and clinical characteristics of tumors in this population are needed.
authors.affiliation: Department of Radiation Oncology, Medical College of Wisconsin, 9200 West Wisconsin Avenue, Milwaukee, WI 53226, USA.
authors.forename: Malika L
authors.initials: ML
authors.lastname: Siker
authors.forename: Meihua
authors.initials: M
authors.lastname: Wang
authors.forename: Kimberly
authors.initials: K
authors.lastname: Porter
authors.forename: Diana F
authors.initials: DF
authors.lastname: Nelson
authors.forename: Walter J
authors.initials: WJ
authors.lastname: Curran
authors.forename: Jeff M
authors.initials: JM
authors.lastname: Michalski
authors.forename: Luis
authors.initials: L
authors.lastname: Souhami
authors.forename: Arnab
authors.initials: A
authors.lastname: Chakravarti
authors.forename: W K Alfred
authors.initials: WK
authors.lastname: Yung
authors.forename: John
authors.initials: J
authors.lastname: Delrowe
authors.forename: Christopher T
authors.initials: CT
authors.lastname: Coughlin
authors.forename: Minesh P
authors.initials: MP
authors.lastname: Mehta
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000375:Aging; D001932:Brain Neoplasms / Q000401:mortality / Q000532:radiotherapy*; D005260:Female; D005909:Glioblastoma / Q000401:mortality / Q000532:radiotherapy*; D006801:Humans; D017567:Karnofsky Performance Status; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D018787:Radiation Oncology / Q000379:methods*; D012189:Retrospective Studies; D012955:Societies, Medical / Q000706:statistics & numerical data; D013997:Time Factors; D055815:Young Adult