How ethical is human radiation experiments?

Abstractly human radiation when used with patients' consent with full understanding of why it will be used being in the light in regards to its benefits and adversities, is in my opinion ethical.
when further supported by the fact that all the 'before' medical means of cure and intervention have been resorted to with no avail leaving no other alternative than radiation with the assurance that the medical case will not further deteriorate if unsuccessful then by all means radiation is ethical.