Initial Experience with CT-Guided High-Dose-Rate Brachytherapy in the Multimodality Treatment of Neuroendocrine Tumor Liver Metastases.

PURPOSE: To evaluate efficacy of computed tomography (CT)-guided high-dose-rate brachytherapy (HDRBT) of neuroendocrine liver metastases (NELM) with the goal of local tumor control (LTC). MATERIALS AND METHODS: This retrospective study included all patients with unresectable NELM treated with CT-guided HDRBT between January 2007 and April 2015. Magnetic resonance imaging follow-up was performed 6 weeks after ablation and then every 3 months. The primary endpoint was LTC. Secondary endpoints included progression-free survival (PFS), overall survival (OS), and complications. RESULTS: In 27 patients, 52 NELM were treated in 40 sessions. Three patients (11.1%) developed local progression with LTC of 1.9-36.8 months (median 10.4 months, mean 16.4 months). The remaining 24 patients (89.9%) had LTC of 3.1-106.1 months (median 31.3 months, mean 32.6 months). Progression or death was observed in 19 patients (70.4%) with PFS of 1.9-55.3 months (median 7.3 months, mean 16.3 months); the remaining 8 patients (29.6%) had PFS of 3.7-50.1 months (median 13.4 months, mean 19.6 months). Four patients (14.8%) died of causes unrelated to the procedure; their OS was 11.7-52.3 months (median 48.7 months, mean 40.4 months). OS was 4.2-106.1 months (median 30.3 months, mean 34.1 months) in the 23 surviving patients (85.2%). One patient experienced pain with nausea and vomiting, and 1 patient with biliodigestive anastomosis had a hepatic abscess. CONCLUSION: CT-guided HDRBT is a promising therapy with excellent LTC rates and low morbidity for patients with isolated/oligometastatic NELM.