Based on the currently available theoretical and experimental data on the prospects and problems of using inorganic nanoparticles in oncology, the opportunities for design of an agent, which is a nanostructured complex of bismuth oxide and photodithazine, are discussed with a view to its potential application for detecting and possibly treating malignant neoplasms. The proposed approach mainly consists in bismuth oxide radioluminescence at a maximum of 550 nm. The initial results give reason to believe that this radiation can affect malignancy and cause the decomposition of photodithazine with the release of singlet oxygen, which enhances the effect of cell destruction.