Basically in those cases, the Oregon health system is refusing to pay for cancer drugs for certain cancer patients whose treatment they don't deem worthwhile (at the same time they are also explicitly offering to pay for the drugs for a physician-assisted suicide, but that is another matter). In those cases it is state bureaucrats who are making the decision about treatment; these are patients who cannot afford private coverage.

The two cases I'm specifically aware of from last year involved patients named Barbara Wagner and Randy Stroup. As far as I can tell the policy has not been revised since, although after the bad PR they are not pushing euthanasia so hard. In any case, Wagner's case was only resolved when the drug company offered to donate the medicine.

The reason I take Palin's scenario more seriously than I might otherwise is not because it bears a particular relation to the European experience, but because it describes things already happening in the US on a smaller scale.