Why is it that cancer cells stimulate angiogenesis even if they are known to constitutively perform glycolysis?

Wow...molecular: Listen, i'm just a practicing oncologist but i'll give it a crack. If i remember well, glycolysis is a fairly ineffective way to produce ATP compared to cellular respiration so my guess would be that malignant cell will still try to go the route that provides the best production of energy. This requires oxygen and by necessity requires blood flow, achieved by neovascularization thru angiogenesis.