The aim of this non-randomised, prospective study is to investigate the applicability and prognostic value of angiogenesis PET/MR with the radioligand 68Ga-NODAGA- E[c(RGDyK)]2 in patients with sporadic Vestibuarl Schwannomas.

The radioligand 68Ga-NODAGA- E[c(RGDyK)]2 targets the Arg-Gly-Asp (RGD) sequence known to bind with the αvβ3 integrin that is expressed on the surface of angiogenic blood vessels or tumor cells. The radioligand can be used to visualize tumor angiogenesis using PET/MR.

A total of 40 patients diagnosed with sporadic vestibular schwannomas will be subjected to an angiogenesis-PET/MR scan. Follow-up MR-only scan will be performed (from the time of the angiogenesis PET/MR) minimum 2 months later in regards to calculate growth rate. The uptake of 68Ga-NODAGA-E[c(RGDyK)]2 (Standardized Uptake Values, SUVmax) in tumor lesions will be quantified as Standardized Uptake Values (SUVmax/SUVmean) and compared with PFS, DSS and OS (dichotomized above/below median SUVmax and analyzed by Kaplan-Meier).

Inclusion Criteria:

• Patients > 18 years with MRI verified sporadic vestibular schwannomas
• Patients > 18 år whom max has been in watchful waiting regime in 12 months and/or max. received 1 follow-up MRI scan.
• Must be able to read and understand the patient information in Danish and to give informed consent

Exclusion Criteria:

• Pregnancy
• Breast-feeding
• Weight more than the maximum weight limit for the PET/MR bed of the scanner (140 kg)
• History of allergic reaction attributable to compounds of similar chemical or biologic composition to 68Ga-NODAGA-E[c(RGDyK)]2
• Recent systemic treatment with steroids
• Hormone treatment incl. birth control pills.
• Claustrofobia
• Non-MRI compatible implants.