⁹⁰Y/¹⁷⁷Lu-DOTATATE therapy: survival of the fittest?

Excerpt

In this issue, Kunikowska et al. [1] provide a landmark study with the first clinical use of a combination of simultaneously administered (“cocktail”) radio-nuclides. In their theoretical paradigm [2], each radio-isotope with its spectrum of emitted beta energies has an optimal target diameter in which most of the beta energy is absorbed and so-called “energy escape” prevented, thereby optimising the radiation dose to the tumour. A cocktail of 50% ⁹⁰Y-DOTATATE (“⁹⁰Y”) + 50% ¹⁷⁷Lu-DOTATATE (“¹⁷⁷Lu”) was used in 25 patients and compared to another group of 25 patients treated by ⁹⁰Y-DOTATATE only. This followed pre-clinical work by de Jong et al., who, using a neuro-endocrine tumour rat model with one small and one large tumour subcutaneously implanted, found striking differences in overall survival and progressive disease in favour of the combination ⁹⁰Y+¹⁷⁷Lu compared with each single-agent treatment. Kunikowska et al. found greater overall survival in patients treated with ⁹⁰Y+¹⁷⁷Lu than with ⁹⁰Y alone and concluded that the tandem therapy is more effective, although tumour response and progression-free survival were not significantly different. …