Sally Roberts has blamed legislation for stopping her son Neon from receiving alternative therapy.
Speaking exclusively to Daybreak, Ms Roberts said that the 1939 Cancer Act means doctors are prevented from using anything but radiotherapy to treat him.
Ms Roberts wants her son to have other treatments instead over fears the radiotherapy could harm him overall health even if it treats the cancer.
She said her fears stem from the radiotherapy "damaging the DNA, altering it. And him never recovering from that."
Ms Roberts said that the legislation prevents research in to other treatments which might help Neon.
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