Tumour-absorbed dose and efficacy of peptide receptor radionuclide therapy with [(90)Y]Y-DOTATOC in patients with refractory meningioma: a single-centre experience.

内容摘要

The management of treatment-refractory meningioma in patients with previous surgical resection and radiation therapy remains challenging due to the lack of effective systemic treatment options. Therefore, novel therapeutic applications, such as peptide receptor radionuclide therapy (PRRT) targeting somatostatin receptors, may offer a promising therapeutic strategy. We aimed to assess the lesion-based tumour-absorbed dose and efficacy of PRRT with [90Y]Y-DOTATOC in patients with treatment-refractory meningioma. In this study, 10 patients with therapy-refractory meningioma were retrospectively included. All patients received systemic [90Y]Y-DOTATOC therapy following prior surgical resection and radiation therapy. In total, 21 lesions were assessed morphologically by contrast-enhanced MRI and [68Ga]Ga-DOTATOC PET/CT both before and after therapy. All patients underwent dosimetry with [111In]In-DOTATOC prior to [90Y]Y-DOTATOC therapy. Treatment response was evaluated according to RANO bidimensional and volumetric criteria. Overall survival (OS) was defined from the first PRRT cycle until death. The median cumulative activity administered per patient was 3804 MBq (IQR, 3140-4050 MBq), with a median of 3 cycles (range: 1-7). On lesion-based analysis following PRRT, response assessment was available in 19/21 (91.5%) lesions. Among these, tumour stabilisation according to RANO criteria was observed in 7/19 (36.8%) lesions, with a median cumulative tumour-absorbed dose of 52.7 Gy. Morphological tumour progression was noted in 12/19 (63.2%) lesions, with a median cumulative tumour-absorbed dose of 43.8 Gy. The difference in tumour-absorbed doses between morphologically stable and progressive lesions according to RANO criteria was not statistically significant (P = 0.82). Values for SUVmax and SUVmean from pretherapeutic [68Ga]Ga-DOTATOC PET/CT significantly correlated with the tumour-absorbed doses (P = 0.018 for SUVmax, P = 0.021 for SUVmean, respectively). Post-therapeutic [68Ga]Ga-DOTATOC PET/CT demonstrated an increase in SUVmax in 19/21 (90.5%) lesions (median: 40.8%, range: 13.0% - 101.2%). The median OS in the whole cohort was 23.0 months (95% CI 12.5-33.5 months). Our preliminary results indicate no significant difference in tumour-absorbed doses between morphologically stable lesions and those with progressive disease, as defined by the RANO criteria. However, lesion-based analysis revealed a significant correlation between pretherapeutic [68Ga]Ga-DOTATOC PET/CT uptake and tumour-absorbed doses following [90Y]Y-DOTATOC therapy. These findings suggest that baseline PET/CT may serve as a valuable tool for estimating cumulative tumour-absorbed dose and guiding the optimal cumulative activity of PRRT.