Table 4.

Multivariate Analysis of Overall Survival and Progression-Free Survival in Oligodendrogliomas

Overall survival with 1p/19q FISH criteria			Progression-free survival with 1p/19q FISH criteria
Variable	Relative Risk (95% CI)	p	Variable	Relative Risk (95% CI)	p
age < 45 y	0.12 (0.042—0.37)	0.0002	age < 45 y	0.25 (0.11—0.60)	0.0017
GTR or STR	0.51 (0.16—1.6)	0.24	GTR or STR	0.52 (0.17—1.5)	0.24
adjuvant Rx	0.62 (0.26—1.5)	0.29	adjuvant Rx	0.58 (0.26—1.3)	0.18
WHO grade II	0.16 (0.065—0.39)	0.0001	WHO grade II	0.14 (0.060—0.34)	0.00001
1p19q codeleted	1.68 (0.47—6.1)	0.42	1p19q codeleted	1.8 (0.58—5.8)	0.31
10q intact	0.36 (0.15—0.88)	0.026	10q intact	0.41 (0.18—0.95)	0.037
Overall survival with 1p/19q PCR-based LOH			Progression-free survival with 1p/19q PCR-based LOH
Variable	Relative Risk (95% CI)	p	Variable	Relative Risk (95% CI)	p
age < 45 y	0.15 (0.048—0.44)	0.0007	age < 45 y	0.27 (0.11—0.63)	0.0025
GTR or STR	0.75 (0.30—1.9)	0.55	GTR or STR	0.79 (0.32—1.9_	0.61
adjuvant Rx	0.75 (0.31—1.8)	0.52	adjuvant Rx	0.69 (0.30—1.6)	0.39
WHO grade II	0.13 (0.048—0.34)	0.00001	WHO grade II	0.13 (0.050—0.32)	0.00001
1p19q LOH	0.44 (0.15—1.3)	0.13	1p19q LOH	0.59 (0.22—1.6)	0.30
10q intact	0.46 (0.19—1.1)	0.09	10q intact	0.51 (0.22—1.2)	0.12

Sixty-four grade II and 20 grade III oligodendrogliomas were modeled by Cox Proportional Hazards according to key clinical, histologic, and molecular variables. The most powerful factors for favorable progression-free and overall survival were age <45 years, WHO grade II histology, and intact 10q (underlined). When incorporating 10q status with the multivariate analyses, 1p/19q status was not an independently prognostic variable. CI = confidence interval; FISH = fluorescence in situ hybridization; GTR = gross total resection; LOH = loss of heterozygosity; STR = subtotal resection. (Relative to the 1p/19q FISH data, similar p values were seen when using the modified 1p/19q FISH criteria, not shown.)