Pérez García, Victor M.. Molina García, David. Pérez Beteta, Julián. Bosque Martínez, Jesús. García Vicente, Ana M.. 

Objective The normalized distance from the metabolic hotspot to the tumor centroid (NHOC) in Positron Emission Tomography (PET) scans is an imaging biomarker previously shown to have prognostic value in non-small cell lung cancer (NSCLC) and breast cancer (BC). The primary objective of this study was to assess whether this metric could also possess prognostic value in high-grade glioma patients. Methods We retrospectively collected 18F-FCHOL diagnostic PET studies from 61 patients with confirmed high-grade glioma. We delineated the metabolically active tumor regions and calculated the geometrical tumor centroid. SUVpeak was obtained and its distance to the geometrical centroid calculated and normalized by the mean spherical radius—a linear measure of tumor size. We used this metric (NHOCpeak) and SUVpeak to perform survival analysis using the Kaplan–Meier method and multivariable Cox regression analysis. Results Patients with low SUVpeak and low NHOCpeak, the most beneficial group, had the longest survival, with a median benefit of 16.4 months (p=0.017) compared to the second best (high NHOCpeak/low SUVpeak). Patients with low NHOCpeak and low SUVpeak had a median survival gain of 21.9 months (p<0.001) with respect to the group with the worst outcome (high SUVpeak/high NHOCpeak). NHOCpeak (p=0.02) and SUVpeak (p<0.001) were uncorrelated (rho=0.094) and separated patients in groups with different median survivals (10.1 and 7.7 months respectively). Taking NHOCpeak and SUVpeak as independent variables for the location and activity in the hotspot, we separated the patient cohort into four groups (high/low NHOCpeah and high/low SUVpeak). Conclusions The metric NHOCpeak, calculated as the relative distance between the hotspot of activity and the tumor centroid normalized by tumor size, provides complementary spatial information to SUVpeak, and their combination may improve prognostic stratification in high-grade glioma imaged with 18F-FCHOL.