Seystahl and colleagues [38] investigated the safety and effectiveness of PRRT in a cohort of 20 patients affected by progressive or therapy-refractory meningiomas and also correlated clinical outcome with pre-therapeutic expression of SSR2 assessed through 68Ga-DOTATATE PET/CT (n = 17) or 111In-pentetreotide scintigraphy (n = 3). The gene discussed is SSR2; the disease is meningioma.