Aim: This study was carried out to compare the efficacy of Y, Lu, and combination of both radiotracers (tandem) peptide receptor radionuclide therapy (PRRT) in patients with inoperable and metastatic neuroendocrine tumors.
Materials and methods: Systematic searches of PubMed and SciVerse Scopus databases were performed till December of 2016. The data were categorized into three groups: Y-PRRT, Lu-PRRT, and tandem-PRRT. Each group was subdivided on the basis of the response criteria used: Response Evaluation Criteria in Solid Tumors (RECIST) or Southwest Oncology Group (SWOG) criteria. Disease response and disease control rates of each group were analyzed.
Results: For the RECIST group, Y-PRRT disease response rates ranged from 22.81 to 56.1%, with a pooled random effect of 42.92%, and the disease control rate was 100%. Lu-PRRT disease response rates ranged from 27.63 to 57.35%, with a pooled random effect of 33.41%, and disease control rates ranged between 71.88 and 100%, with a pooled fixed effect of 79.32%. As for tandem-PRRT, disease response rates ranged between 42.11 and 66.67%, with a pooled fixed effect of 50.52%, and the disease control rate ranged between 93.33 and 100%, with a pooled fixed effect of 98.97%.For the SWOG group, Y-PRRT disease response rates ranged from 5.13 to 26.56%, with a pooled random effect of 13.4%, and disease control rates ranged between 76.56 and 85.9%, with a pooled fixed effect of 80.93%. Lu-PRRT disease response rates ranged from 6.06 to 60.29%, with a pooled random effect of 26.4%, and the disease control rates between 48.48 and 85.29%, with a pooled random effect of 74.53%.
Conclusion: Y-PRRT had the highest disease control rates under both RECIST and SWOG criteria. Tandem-PRRT had the highest disease response rate in the RECIST criteria, indicating that PRRT should be customized to each patient individually for maximum benefit.