Phase III trial of chemoradiotherapy for anaplastic oligodendroglioma: long-term results of RTOG 9402.
OBJECTIVE
Anaplastic oligodendrogliomas, pure (AO) and mixed (anaplastic oligoastrocytoma [AOA]), are chemosensitive, especially if codeleted for 1p/19q, but whether patients live longer after chemoradiotherapy is unknown.


METHODS
Eligible patients with AO/AOA were randomly assigned to procarbazine, lomustine, and vincristine (PCV) plus radiotherapy (RT) versus RT alone. The primary end point was overall survival (OS).


RESULTS
Two hundred ninety-one eligible patients were randomly assigned: 148 to PCV plus RT and 143 to RT. For the entire cohort, there was no difference in median survival by treatment (4.6 years for PCV plus RT v 4.7 years for RT; hazard ratio [HR] = 0.79; 95% CI, 0.60 to 1.04; P = .1). Patients with codeleted tumors lived longer than those with noncodeleted tumors (PCV plus RT: 14.7 v 2.6 years, HR = 0.36, 95% CI, 0.23 to 0.57, P < .001; RT: 7.3 v 2.7 years, HR = 0.40, 95% CI, 0.27 to 0.60, P < .001), and the median survival of those with codeleted tumors treated with PCV plus RT was twice that of patients receiving RT (14.7 v 7.3 years; HR = 0.59; 95% CI, 0.37 to 0.95; P = .03). For those with noncodeleted tumors, there was no difference in median survival by treatment arm (2.6 v 2.7 years; HR = 0.85; 95% CI, 0.58 to 1.23; P = .39). In Cox models that included codeletion status, the adjusted OS for all patients was prolonged by PCV plus RT (HR = 0.67; 95% CI, 0.50 to 0.91; P = .01).


CONCLUSIONS
For the subset of patients with 1p/19q codeleted AO/AOA, PCV plus RT may be an especially effective treatment, although this observation was derived from an unplanned analysis.
Department of Clinical Neurosciences, Foothills Medical Centre, 1403 29th St NW, Calgary, Alberta, Canada T2N 2T9. jgcairnx@ucalgary.ca
Gregory
G
Cairncross
Meihua
M
Wang
Edward
E
Shaw
Robert
R
Jenkins
David
D
Brachman
Jan
J
Buckner
Karen
K
Fink
Luis
L
Souhami
Normand
N
Laperriere
Walter
W
Curran
Minesh
M
Mehta
D000971:Antineoplastic Combined Chemotherapy Protocols / Q000008:administration & dosage; D001932:Brain Neoplasms / Q000235:genetics / Q000401:mortality* / Q000628:therapy*; D059248:Chemoradiotherapy / Q000379:methods*; D002878:Chromosomes, Human, Pair 1 / Q000235:genetics; D002888:Chromosomes, Human, Pair 19 / Q000235:genetics; D018572:Disease-Free Survival; D017353:Gene Deletion; D006801:Humans; D053208:Kaplan-Meier Estimate; D008130:Lomustine / Q000008:administration & dosage / Q000009:adverse effects; D009837:Oligodendroglioma / Q000235:genetics / Q000401:mortality* / Q000628:therapy*; D011344:Procarbazine / Q000008:administration & dosage / Q000009:adverse effects; D016016:Proportional Hazards Models; D011878:Radiotherapy; D013995:Time; D014750:Vincristine / Q000008:administration & dosage / Q000009:adverse effects
D011344:Procarbazine; D014750:Vincristine; D008130:Lomustine