The aims of this study were to examine prognostic significance of microvessel density
(MVD) in previously-untreated, advanced epithelial ovarian cancer (EOC) and explore
associations between MVD and factors that affect angiogenesis.
MVD was determined by immunohistochemical expression of CD31 or CD105 in tumor sections
from 106 women treated on GOG randomized phase III trials. Average MVD hotspots were
quantified by light microscopy at high power (x400) and categorized as low (<upper
quartile) or high (>or=upper quartile). Immunoblot expression of MASPIN, THBS-1, bFGF,
VEGF, VEGFR-1 and p53 status (mutation and overexpression) was previously determined.
Of 106 evaluable cases, 25% exhibited high CD31-MVD (>24.25 vessels/high power field
[HPF]) or high CD105-MVD (>19.25 vessels/HPF). After adjusting for age and stratifying
by GOG performance status, stage, cell type, grade, debulking status and treatment
regimen, high versus low CD105-MVD was associated with increased risk of disease progression
(hazard ratio [HR]=1.873; 95% confidence interval [CI]: 1.102-3.184; p=0.020), but
not death (HR=1.125; 95% CI: 0.654-1.935; p=0.670) whereas CD31-MVD was not associated
with risk of disease progression (HR=1.578; 95% CI=0.918-2.711; p=0.099) or death
(HR=1.678; 95% CI=0.957-2.943; p=0.071). CD31-MVD was correlated with CD105-MVD (p=0.001)
and MASPIN (p=0.016). Neither CD31-MVD nor CD105-MVD was associated with p53 status,
THBS-1, bFGF, VEGF or VEGFR-1.
High MVD assessed using CD105, a marker of proliferating endothelial cells and neoangiogenesis,
but not CD31 a pan-endothelial marker, appeared to be an independent prognostic factor
for worse progression-free survival in women with advanced EOC after adjusting for
prognostic clinical covariates.