Although Avastin can cost thousands of dollars a month as a cancer treatment, when used in the tiny portions required for eye-disease injections, it costs only about $30 to $50 per shot.But it was unclear how Medicare should reimburse eye doctors for that use of Avastin.lthough Avastin can cost thousands of dollars a month as a cancer treatment, when used in the tiny portions required for eye-disease injections, it costs only about $30 to $50 per shot.