I could bring it down to a very practical approach, to answer the previous questioner.
It's never the cost; it's whether you want to do it and how much you want to do. If you had a pilot study of expensive cancer drugs for two years, sampling major cancer centres' use of those drugs for adverse events and efficacy, and learned from that pilot study as a start, you would have a major step forward in addressing the issue in respect of these expensive but effective cancer drugs.