P06.04 * PEPTIDE RECEPTOR RADIONUCLIDE THERAPY (PRRT) WITH 90Y-DOTATOC TARGETING OF RECURRENT ATYPICAL MENINGIOMA: A CASE REPORT

Abstract

BACKGROUND: At present, limited treatment options are available for patients with meningiomas after surgery and radiotherapy have failed. CLINICAL CASE: A 60 year old female patient presenting with a sensory hemi-syndrome on the right side was diagnosed with an extensive dural based left frontotemporal mass associated with perifocal edema. A gross total resection (GTR) was performed and histological work-up revealed an atypical meningioma WHO grade II. Four years later, MRI showed extensive multifocal tumor progression in the frontal, parietal and occipital lobes without clinical deterioration. Again, the patient underwent GTR of all tumor lesions followed by continuous clinical and imaging follow up visits. Two years later, the patient presented with epileptic seizures and MRI again revealed multifocal tumor progression. Therefore the patient was treated with external beam radiotherapy at a total dose of 59,4 Gy (single fraction 1,8 Gy). Six months after termination of radiotherapy, the performance status of the patient deteriorated and MRI showed enlarging tumor lesions. These tumor lesions revealed strong radiotracer uptake on 68Ga-DOTATOC PET. Based on this high expression of somatostatin receptors, the patient was treatd by peptide receptor radionuclide therapy (PRRT) with 90Y-DOTATOC consisting of 4 cycles (mean dose 4.115 MBq/cycle). This treatment was well tolerated and the patient experienced a significant improvement of the performance status with a reduction of seizure frequency. Three months after termination of peptide receptor radionuclide therapy, disease stabilization could be achieved on MR- and PET-imaging with persisting clinical improvement, which is still ongoing after one year of clinical and imaging follow-up studies. CONCLUSION: A patient with recurrent atypical multifocal meningioma resistant to conventional treatment underwent 4 cycles of peptide receptor radionuclide therapy with 90Y-DOTATOC. After treatment, the patient experienced a significant clinical improvement and a stable tumor disease remained in MRI and PET images. Hence, PRRT proved to be a safe and feasible approach in a palliative treatment setting of recurrent highly somatostatin receptor expressing meningiomas. Nevertheless, prospective clinical trials are warranted to define the value of peptide receptor radionuclide therapy as an additional treatment option for recurrent meningiomas after standard treatment has failed.