The Care Quality Commission is the new health and social care regulator for England.
For example, you can search for your hospital or compare hospitals.
http://2009ratings.cqc.org.uk/findcareservices/informationabouthealthcareservices.cfm
If you look at the Royal Marsden they rank as Excellent across all of the measures, Quality of Services; Meeting Core Standards; Assessment of Existing Commitments; Assessment of National Priorities, etc.