Abstract: Background The potential of a tumour?s volumetric measures
obtained from pretreatment MRI sequences of glioblastoma
(GBM) patients as predictors of clinical outcome has been
controversial. Mathematical models of GBM growth have
suggested a relation between a tumour?s geometry and its
aggressiveness.
Methods A multicenter retrospective clinical study was designed
to study volumetric and geometrical measures on pretreatment
postcontrast T1 MRIs of 117 GBM patients.
Clinical variables were collected, tumours segmented, and
measures computed including: contrast enhancing (CE), necrotic,
and total volumes; maximal tumour diameter; equivalent
spherical CE width and several geometric measures of the
CE ?rim?. The significance of the measures was studied using
proportional hazards analysis and Kaplan-Meier curves.
Results Kaplan-Meier and univariate Cox survival analysis
showed that total volume [p = 0.034, Hazard ratio
(HR)= 1.574], CE volume (p = 0.017, HR= 1.659), spherical
rim width (p =0.007, HR= 1.749), and geometric heterogeneity
(p = 0.015, HR= 1.646) were significant parameters in
terms of overall survival (OS). Multivariable Cox analysis
for OS provided the later two parameters as age-adjusted predictors
of OS (p = 0.043, HR = 1.536 and p = 0.032,
HR=1.570, respectively).
Conclusion Patients with tumours having small geometric heterogeneity
and/or spherical rim widths had significantly better
prognosis. These novel imaging biomarkers have a strong individual
and combined prognostic value for GBM patients.
