Somatostatin-based radiopeptide therapy with [177Lu-DOTA]-TOC versus [90Y-DOTA]-TOC in neuroendocrine tumours

Purpose

Somatostatin-based radiopeptide treatment is generally performed using the β-emitting radionuclides ⁹⁰Y or ¹⁷⁷Lu. The present study aimed at comparing benefits and harms of both therapeutic approaches.

Methods

In a comparative cohort study, patients with advanced neuroendocrine tumours underwent repeated cycles of [⁹⁰Y-DOTA]-TOC or [¹⁷⁷Lu-DOTA]-TOC until progression of disease or permanent adverse events. Multivariable Cox regression and competing risks regression were employed to examine predictors of survival and adverse events for both treatment groups.

Results

Overall, 910 patients underwent 1,804 cycles of [⁹⁰Y-DOTA]-TOC and 141 patients underwent 259 cycles of [¹⁷⁷Lu-DOTA]-TOC. The median survival after [¹⁷⁷Lu-DOTA]-TOC and after [⁹⁰Y-DOTA]-TOC was comparable (45.5 months versus 35.9 months, hazard ratio 0.91, 95 % confidence interval 0.63–1.30, p?=?0.49). Subgroup analyses revealed a significantly longer survival for [¹⁷⁷Lu-DOTA]-TOC over [⁹⁰Y-DOTA]-TOC in patients with low tumour uptake, solitary lesions and extra-hepatic lesions. The rate of severe transient haematotoxicities was lower after [¹⁷⁷Lu-DOTA]-TOC treatment (1.4 vs 10.1 %, p?=?0.001), while the rate of severe permanent renal toxicities was similar in both treatment groups (9.2 vs 7.8 %, p?=?0.32).

Conclusion

The present results revealed no difference in median overall survival after [¹⁷⁷Lu-DOTA]-TOC and [⁹⁰Y-DOTA]-TOC. Furthermore, [¹⁷⁷Lu-DOTA]-TOC was less haematotoxic than [⁹⁰Y-DOTA]-TOC.