Prognostic factors of
M. Frenay, A. Ramaioli, D. Fontaine, V. Bourg, F. Vandenbos, C. Lebrun
Centre Antoine Lacassagne, Nice, France; Hopital Pasteur, Nice,
Oligodendrogliomas (OG) have better prognosis than other
glial tumors, maybe due to a better response to chemotherapy and molecular
profile, as 1p/19q deletions.
We evaluated 100 consecutive patients, representing 9% of
patients with PBT in our database, with newly diagnosed OG from 1995 to 2002, in
order to identifie prognostic factors.
Three subgroups of patients were defined: group A: low
grade (LOG) or grade II; group B: LOG with malignant transformation during the
follow-up or Transformed AOG (TOG); group C: de novo anaplastic (AOG) or
The prognostic significance of individual factors was
evaluated by comparing the 2, 5 and 10-year survival rates.
Patients characteristics were: 66 men, 34 women; median
follow-up: 4 years; mean age at the first symptom: 46 years; mean age at
diagnosis: 46.7 years.
The initial presenting symptom was: partial seizures,
neurological deficit, headache or cognitive changes.
Sixty patients had gadolinium enhancement (A: 15%, C:
After histological diagnosis, symptomatic patients had a
second line of treatment (chemotherapy or radiotherapy).
Mean time for transformation for group B was 72 months
with a median survival of 86 months (14 months after malignant
Survivals at 2, 5 and 10 years were: A: 88%, 88%, 85%; B:
79%, 64%, 42%; C: 43%, 16%, 15% (p<0.0001).
No difference in survival was observed between groups B
and C after the diagnosis of malignant transformation (p=0.57).
Using univariate analysis, age < 40years (p<0.0003),
lack of contrast enhancement at diagnosis (p<0.00001) and epilepsy
(p<0.007) were correlated with good prognosis.
Complete surgery, compared partial resection or biopsy,
did not influence survival time.
In multivariate analysis, the strongest prognostic factor
was lack of contrast enhancement (RR=3.4), followed by revealing symptom
(RR=1.27) and age <40 years (RR=1.04).
Relative risk for the grade II was age < 40years: 1.04;
epilepsy: 1.6; enhancement: 2.66.
For the grade III patients, only age remained significant
OG have a good prognosis.
Whatever the grade considered, contrast enhancement is the
strongest prognostic factor.
Copyright 2004 American Society of Clinical Oncology All rights