The prediction value to the grade of pathology in meningiomas with 99Tcm-HYNIC-octreotide imaging

Objective: Octreotide is a somatostatin analogy with a high affinity to somatostatin receptor subtype 2 (SSTR2). Meningiomas were shown to express SSTR2 above 80%. Convention imaging can be used to diagnose meningioma, but they can not reflect the pathological grade of meningioma. The aim of this study was to explore the relationship between 99Tcm-hydrazinonicotinamide (HYNIC) -octreotide imaging and the pathological grade of meningioma. Methods: Thirty meningiomas were performed head transverse imaging of SSTR scintillography (SRS) with SPECT/CT after 4 h intravenous injection of 740-925 MBq 99Tcm-HYNIC-octreotide. Furthermore, the relationships between tumor and corresponding region of opposite side (T/NT) and its grade of pathology were investigated. All the pathological tissues were checked with immunofluorescence. The l-test was used to compare T/NT ratios. Spearman analysis was used to analyze the relation of T/NT ratios and pathological grade or immunofluorescence. Results Totally 30 meningioma patients were included. The rate of positive imaging and expression of SSTR2 were 100% in all. The value in grade I of meningioma was 4.15 ± 1.59 [90% confidence interval (CI) =1.53 to 6.77] and was 9.78 ± 1.72 (90% CI:6.95 to 12.61) in grade II (t=3.396, P=0.002). Positive correlation relationship between T/NT and the level of immunofluorescence was observed in both grade I and II meningioma (r=0.824, 0.85 1; P<0.01). Conclusion: 99Tcm-HYNIC-octreotide SPECT/CT imaging has potential to predict the pathology grade of meningioma. (authors)