A little update about Avastin. It has been thought for a while that Avastin can actually cause more problems than it solves. Evidence suggested that it can increase the blood flow to the tumour (increased vascularity) and therefore increase tumour invasion, causing more tumours to grow. According to this piece of research published It would seem that this might be true.
Tumour angiogenesis and anti-angiogenic therapy in malignant gliomas revisited
Plate KH et al. – The anti–angiogenesis drug Avastin (Bevacizumab), which targets VEGF, has become one of the most popular cancer drugs in the world. Anti–angiogenic therapy may lead to vascular normalization and as such facilitate conventional cytotoxic chemotherapy. However, preclinical and clinical studies suggest that anti–VEGF therapy using bevacizumab may also lead to a pro–migratory phenotype in therapy resistant glioblastomas and thus actively promote tumor invasion and recurrent tumor growth.
The full abstract can be seen on PubMed.gov, the US National Library of Medicine, National Institutes for Health: www.ncbi.nlm.nih.gov/pubmed/23143192