[۱۸F]FDG PET/CT volumetric biomarkers for non-invasive prediction of HER۲ expression in breast cancer patients

Objective(s): to investigate the capability of ۱۸F-fluorodeoxyglucose positron emission tomography/computed tomography ([۱۸F]-FDG PET/CT) derived volumetric parameters to predict human epidermal growth factor receptor ۲ (HER۲) status in breast cancer patients.Methods: retrospective study enrolled ۴۷ female patients with breast cancer. All patients had pretreatment [۱۸F]-FDG PET/CT. Clinical data, pathology report and HER۲ status were retrieved from medical records. In an attempt to assess the predictive value of the PET-derived metabolic parameters, Receiver operating characteristic (ROC) curve was constructed with area under curve analysis performed to detect best cutoff value of significant parameters for detection of HER۲ positive.Results: No statistically significant difference was noted among both groups (HER۲ positive and negative) in respect to age, menopausal status, histology, grade, T-stage, N-stage, or antigen Kiel ۶۷ (Ki-۶۷) index. ROC curve successfully marked cutoff point ≥۴۲.۳۵ for total lesion glycolysis (TLG) and ³۱۲.۷۵ for metabolic tumor value (MTV) that are capable to discriminate positive versus negative HER۲ expression in breast cancer patients with area under curve (AUC) ۰.۷۲۸ and ۰.۷۲۳ and P-values ۰.۰۰۲ and ۰.۰۰۴ respectively. Such cutoff point was not deduced for standard uptake value (SUV) max. Primary tumor TLG cutoff correlated well with age where ۷۷.۸% of patients with TLG  ³۴۲.۳۵ were older than ۴۵ years old compared to ۲۲.۲% of them who were younger than ۴۵ years, P-value=۰.۰۴۷. Also ۷۰.۳% of patients with TLG exceeds  ³۴۲.۳۵ had T۳ and ۴ primary tumors while ۶۵% of those with TLG <۴۲.۳۵ their primary tumors were T۱ and ۲, P-value=۰.۰۳. As regards Primary tumor MTV cutoff point, significant correlations were noted in respect to T-stage where ۷۸.۲% of the patients with primary tumor MTV ³۱۲.۷۵ were T۳ and ۴, compared to ۶۶.۶% of those with primary tumor MTV <۱۲.۷۵ were T۱ and ۲, P-value=۰.۰۱۱.Conclusion: PET-derived volumetrics may serve as non-invasive predictors of biological processes represented here as HER۲ expression in breast cancer patients.

کلیدواژه ها:

PET/CT ، HER۲ ، Breast Cancer