90Y Radioembolization in the Treatment of Neuroendocrine Neoplasms: Results of an International Multicenter Retrospective Study

In neuroendocrine neoplasms (NENs), the presence of distant metastases has a severe impact on survival leading to a relevant decrease in the 5-y survival rate. Here, Y-90 radioembolization (Y-90 RE) might be an important treatment option; however, data to support clinical benefits for Y-90 RE are scarce. Therefore, the purpose of this study was to analyze the use of Y-90 RE in NEN patients with hepatic metastases in an international, multicenter retrospective analysis and assess the potential role of Y-90 RE in a multimodal treatment concept. Methods: In total, 297 angiographic evaluations in NEN patients before Y-90 RE were analyzed. Baseline characteristics and parameters derived from imaging evaluation and Y-90 RE were analyzed. Tumor response was assessed using RECIST 1.1, and survival data were collected. Mean overall survival (OS) between different groups was compared using Kaplan-Meier curves and the log rank test. A P value of less than 0.05 indicated statistical significance. Results: After Y-90 RE, the disease control rate according to RECIST 1.1 was 83.5% after 3 mo and 50.9% after 12 mo. OS in the entire population was 38.9 +/- 33.0 mo. High tumor grade (P < 0.006) and high tumor burden (P = 0.001) were both associated with a significant decrease in OS. The presence of extrahepatic metastases (P = 0.335) and the type of metastatic vascularization pattern (P = 0.460) had no influence on OS. Patients who received Y-90 RE as second-line therapy had a slightly longer but not statistically significant OS than patients who had Y-90 RE in a salvage setting (44.8 vs. 30.6 mo, P = 0.078). Hepatic and global progression-free survival after Y-90 RE was significantly decreased in heavily pretreated patients, compared with patients with second-line therapy (P = 0.011 and P = 0.010, respectively). Conclusion: Y-90 RE could be an important alternative to peptide receptor radionuclide therapy as second-line treatment in patients with progressive liver-dominant disease pretreated with somatostatin analogs.

Automated summary

Y-90 radioembolization (Y-90 RE) could be an important alternative treatment option for neuroendocrine neoplasms (NENs) patients with hepatic metastases, but more clinical evidence is needed.