> Making the glucose the patient intakes mildly radioactive The carbon and oxygen in glucose used as fuel doesn't stay in the cell - it becomes lactic acid (or

> Making the glucose the patient intakes mildly radioactive The carbon and oxygen in glucose used as fuel doesn't stay in the cell - it becomes lactic acid (or carbon dioxide and water), which leaves the cell. You could make a weaponised version of something which does get retained in the cancer cell. For example, nucleosides, which are the raw material for DNA, and which are needed in volume to support cancer cells' rapid proliferation. These drugs are called nucleoside analogues, and are used to treat cancer and viruses: https://en.wikipedia.org/wiki/Gemcitabine https://en.wikipedia.org/wiki/Gemcitabine