My mother started avastin in the beginning of August and it took about a couple of weeks before we started noticing that she was getting more alert. The tumor shrank 1.2 cm which is to me a good sign, in June it was 4.5cm. She started with 7cm in February and now it's at 3.3cm I understood that it depends on each individual and how well they respond to it.
My husband just began avastin one month ago. I am wondering the same question as you and notice there has been no response. I too am interested in the timeline and length of treatment.