Total Lesion Glycolysis and Sequential (90)Y-Selective Internal Radiation Therapy in Breast Cancer Liver Metastases: Preliminary Results.

To assess the prognostic role of total lesion glycolysis (TLG) in patients with breast cancer liver metastases (BCLM) after sequential lobar (90)Y-radioembolization ((90)Y-RE). Seventeen patients with bilobar BCLM underwent FDG PET/CT and TLG calculation before (90)Y-RE. The hepatic lobe with the highest TLG was treated in the first session. PET was performed 6 weeks postprocedure and decrease in TLG (ΔTLG) in the treated lobe was calculated before the second (90)Y administration. Subjects were divided in two groups (group 1: ΔTLG >50%, group 2: ΔTLG <50%). After the two consecutive (90)Y-therapies, patients underwent follow-up until death. Statistical analysis was performed to identify prognostic factors on overall survival (OS). After the first (90)Y administration, 10 cases showed a ΔTLG >50% and seven had a ΔTLG value <50%. After the two consecutive procedures, the mean OS for all patients was 13.5 ± 0.8 months. Subjects with a ΔTLG >50% and ΔTLG <50% had a mean OS of 16.4 ± 0.6 and 10.3 ± 0.4 months, respectively (p < 0.001). Cox regression analysis demonstrated hepatic tumor load (p = 0.048) and ΔTLG as the only significant (p = 0.005) predictors of survival. ΔTLG after the first (90)Y administration agrees with final outcome in BCLM patients after separate sequential lobar (90)Y-RE.