Avastin treatment

My name is Gary and I am 42. I have Stage IV Mets Bladder Cancer. I need molecular therapy. One of the drugs is called Avastin. My Aetna PPO has denied my oncologists request for this therapy.
Has anyone had this drug approved through their insurance company? Has anyone had success with this method of treatment?
I am currently undergoing chemo and have had 26 radiation treatments. The chemo makes me terribly sick and will not work much longer.
I had a complete bladder removal/rebuild in Aug. 2007 and the cancer came back.
Can anyone help me? My wife and I are desperate to find someone who has had this treament so we can file an appeal with our insurance company.