Abstract
Peptide receptor radionuclide therapy (PRRT) has been used for more than twenty years as a systemic treatment approach in inoperable or metastatic somatostatin receptor (SSTR)-positive tumors. The purpose of this study was to analyze the long-term outcome of PRRT with regard to the most commonly used radiopharmaceuticals, 90Y-DOTA-Tyr3-octreotide (90Y-DOTA-TOC) and 177Lu-DOTA-Tyr3-octreotate (177Lu-DOTA-TATE). Methods: This retrospective clinical study included a total of 44 consecutive patients (27 men) with advanced tumors and enhanced SSTR expression. Mean age at initial diagnosis was 60 years (SD 11.3, range 40 to 84 years). Median follow-up was 80 months. In the mean 5.3 ± 2.5 cycles were administered for 177Lu-PRRT with mean activity of 27.2 ± 14.9 GBq per patient and 5.5 ± 2.6 cycles for 90Y-PRRT with mean activity of 14.7 ± 7.3 GBq. Overall, 378 cycles were administered (mean 8.6 ± 3.4 cycles per patient) with an overall cumulative activity of 1514.1 GBq. Results: Median overall survival (OS) was 79 months. Twenty-one (77.8%) of the 27 men and nine (52.9%) of the 17 women had died 12 years after commencement of PRRT. Shortest duration of illness was eight months, longest 155 months. Severe side-effects (WHO Grades III and IV) are seen in nine of the 14 patients still alive. Chronic kidney disease in combination with anemia is the most common finding in the nine patients with severe side-effects. Very poor prognosis was found for those patients who showed progressive disease (PD) in comparison with patients with cumulative disease control after initial PRRT (log-rank, p<0.001), while women and patients with no more than two tumor sites seem to especially benefit from PRRT not reaching significance levels. Conclusion: PRRT is very encouraging in terms of long-term outcome. Thirty-two percent (14/44 patients) of the patients with metastatic or inoperable disease are still alive more than 12 years after the beginning of radionuclide therapy. Possible predictors for favourable outcome are initial response to PRRT, number of affected sites and female gender.
- Neuroendocrine
- Oncology: GI
- Radionuclide Therapy
- Long-term outcome
- Neuroendocrine tumors
- Overall survival
- PRRT
- Radionuclide therapy
- Copyright © 2018 by the Society of Nuclear Medicine and Molecular Imaging, Inc.