Alternative volumetric PET parameters for evaluation of breast cancer cases with 18F‐FDG PET/CT imaging: Metabolic tumour volume and total lesion glycolysis

We aimed to investigate the prognostic and clinical values of two volumetric PET parameters used in conjunction with SUV max at different thresholds in invasive ductal carcinoma (IDC). Methods A total of 139 metastatic IDC BC who underwent 18F‐FDG PET/CT imaging were included to study. MTV and TLG (40%, 50%, 60% and 70%) used in conjunction with primary tumour SUV max . Nodal involvement, distant metastasis, ER, PR, Ki‐67 expression and survival data evaluated by comparing FDG PET parameters. Results Mean ± SD SUV max of lesions ( n  = 139) was 13.97 ± 9.21. Primary tumour 18F‐FDG uptake associated increased tumour diameter (>2 cm), high Ki‐67 (>15%) and distant organ metastasis (DOM) ( P  = 0.015, 0.005 and 0.016, respectively). There was significant association between molecular subtypes and SUV max ( P  = 0.002). High MTV associated with tumour diameter (MTV 40–70%), axillary lymph node (ALN) diameter (MTV 40–70%), and distant nodal metastasis (DNM) (MTV 50–70%). High TLG associated with tumour diameter (TLG 40–70%), high Ki‐67 (TLG 40–70%), ALN metastasis (TLG 40%), ALN diameter (TLG 40–70%) and DNM (TLG 40–70%). Median survival found shorter in DOM patients ( P  = 0.030, Log Rank = 0.110). Conclusion We think evaluation of MTV and TLG at different thresholds in addition to SUV max would enhance diagnostic and prognostic value of 18F‐FDG PET/CT, and thus contribute to disease management.