Relationships of 18F-FDG uptake by primary tumors with prognostic factors and molecular subtype in ductal breast cancer

Abstract

Objectives: In this study, we aimed to investigate the correlation between SUVmax of primary tumor and prognostic factors/molecular subtype in ductal breast cancer patients. Materials and methods: We retrospectively reviewed 150 female patients with pathologically proven invasive ductal breast cancer from January 2015 to October 2019 who underwent 18F-FDG PET/CT for initial staging. Histopathological prognostic features of the primary tumor (histological grade, hormone receptor status, Ki-67 index, vb.) were obtained from the tru-cut biopsy report. In 18F-FDG PET/CT studies, the maximum standardized uptake value (SUVmax) of the primary breast tumor was calculated and compared with the presence of axillary lymphadenopathy and/or distant metastases, histopathological prognostic factors and molecular subtype. Results: The high SUVmax of primary breast tumors is significantly correlated with the clinicopathological factors: high tumor size, high histologic grade, high Ki-67 index, axillary lymph node positivity and distant metastasis. SUVmax value was significantly higher in patients with basal subtype than patients with Luminal A subtype (8.14 ± 3.71 and 4.64 ± 2.45, p = 0.002). Correlation analysis revealed a low correlation between Ki-67 index and SUVmax (r = 0.276, p = 0.001) and moderate correlation between tumor size and SUVmax (r = 0.470, p = 0.001). In multivariate linear regression analysis, Ki-67 index and tumor size had a statistically significant effect on SUVmax values. As these parameters increase, it is seen that it increases SUVmax values (p = 0.004, Std Beta: 0.228, 95% CI: 0.010–0.055 and p = 0.001, Std Beta: 0.374, 95% CI: 0.55–0.136, respectively). Conclusión: High SUVmax value is associated with prognotic factors suggesting poor prognosis. Pretreatment 18F-FDG PET/CT can be used as a tool to predict prognosis in breast cancer. © 2021 Sociedad Española de Medicina Nuclear e Imagen Molecular