3 strikes and yer out!
A good cause undoubtedly, but surely there are better / easier ways to raise funds for your charity trip that an empty blog with (traditionally poor paying) adverts on it.
Have you though about some mini-events you could do over the next year with sponsorship, or perhaps setting up some sort of charitable small business or event?
People come up with thousands of ideas every year (think children in need etc) - why not copy some of them?
Just to re-iterate am not against your cause or charity in general - almost everyone has been touched by cancer in some way - just trying to suggest things that might actually get you to China!
Eighty percent of success is showing up.