It depends on whom you ask. If you ask NICE, they will tell you they have turned down only two cancer drugs in all of their history. If you ask the cancer community, they will say they have turned down 40-odd. The difference is that NICE will count.... If we say yes to a specific subgroup that is not all clinically indicated, we are saying yes. The patient advocacy groups will tend to say that unless you say yes to every patient group that is named in the licence, you are saying no.
Overall, the access to cancer drugs and most innovative medicines is pretty effective. There are a few exceptions, but overall there is very good access at reasonable prices.