Dose-Response Relationship in Patients with Liver Metastases from Neuroendocrine Neoplasms Undergoing Radioembolization with ⁹⁰Y Glass Microspheres.

Abstract

The benefit of multicompartment dosimetry in the radioembolization of neuroendocrine neoplasms is not firmly established. We retrospectively assessed its potential with patient outcome. <b>Methods:</b> Forty-three patients were eligible. The association of mean absorbed dose (MAD) for tumors and treatment response was tested per lesion with a receiver operating characteristic curve analysis, and the association of MAD with progression-free survival (PFS) and overall survival was tested per patient using uni- and multivariate Cox regression analyses. <b>Results:</b> The area under the curve for treatment response based on MAD was 0.79 (cutoff, 196.6 Gy; <i>P</i> < 0.0001). For global PFS, grade (grade 2 vs. 1: hazard ratio [HR], 2.51; <i>P</i> = 0.042; grade 3 vs. 1: HR, 62.44; <i>P</i> < 0.001), tumor origin (HR, 6.58; <i>P</i> < 0.001), and MAD (HR, 0.998; <i>P</i> = 0.003) were significant. For overall survival, no prognostic parameters were significant. <b>Conclusion:</b> In line with prior publications, a MAD of more than 200 Gy seemed to favor treatment response. MAD was also associated with PFS and may be of interest for radioembolization planning for neuroendocrine neoplasm patients.