Prognostic Value of Tumor Heterogeneity on 18F-FDG PET/CT in HR+HER2− Metastatic Breast Cancer Patients receiving 500 mg Fulvestrant: a retrospective study

Abstract

Heterogeneity has been demonstrated to be a predictor of treatment failure and drug resistance. Our study aimed to investigate imaging parameters, including tumor heterogeneity, as prognostic factors of response to 500 mg fulvestrant using 18F-FDG PET/CT. Twenty-seven estrogen receptor (HR)-positive/HER2-negative metastatic breast cancer patients who received 500 mg fulvestrant and underwent 18F-FDG PET/CT before treatment were retrospectively included. In PET/CT scans, conventional parameters (maximum and mean standardized uptake value, metabolic tumor volume [MTV], total lesion glycolysis [TLG]) and heterogeneity parameters (intra-tumor heterogeneity index [HI] and inter-tumor heterogeneity coefficient of variation [COV]) were analyzed. Progression-free survival (PFS) was mainly assessed for efficacy. The survival analyses were performed using the Kaplan–Meier method. Univariate and multivariate analysis were performed using the Cox proportional hazard model. Univariate analysis indicated that a high SUVmax and a high tumor HI at baseline were associated with longer PFS of fulvestrant (P = 0.036 and P = 0.033, respectively). Liver metastasis, SUVmax and HI were statistically significant in multivariate analysis (P values of 0.017, 0.025 and 0.043, respectively). 18F-FDG based intra-tumor heterogeneity appears to be a potential predicator of efficacy of fulvestrant among HR+HER2− metastatic breast cancer patients.

Prognostic Value of Dual-Time-Point 18F-Fluorodeoxyglucose PET/CT in Metastatic Breast Cancer: An Exploratory Study of Quantitative Measures

“…However, SUVmax was found to be associated with patients' overall survival in other studies on breast cancer patients with distant metastasis [8,9,18,19]. It has also been reported that MTV and TLG were not predictive of patients' overall survival [18], which stands in contrast to our results.…”

“…However, SUVmax was found to be associated with patients' overall survival in other studies on breast cancer patients with distant metastasis [8,9,18,19]. It has also been reported that MTV and TLG were not predictive of patients' overall survival [18], which stands in contrast to our results. One reason could be the long follow-up time of our study (approximately 29 months) compared to previous studies with follow-up times of 15.6 [18], 26.6 [8], and 22.3 months [9].…”

“…It has also been reported that MTV and TLG were not predictive of patients' overall survival [18], which stands in contrast to our results. One reason could be the long follow-up time of our study (approximately 29 months) compared to previous studies with follow-up times of 15.6 [18], 26.6 [8], and 22.3 months [9].…”

“…Various imaging modalities have been suggested for diagnosing recurrent breast cancer, among which 18 F-fluorodeoxyglucose positron emission tomography (FDG-PET) with integrated computed tomography (FDG-PET/CT) is more accurate when compared to conventional imaging techniques [3]. FDG-PET/CT is even more accurate compared to conventional imaging in the detection of bone metastases (bone being one of the most probable sites of metastases in breast cancer) [4].…”

Treatment-related changes in neuroendocrine tumors as assessed by textural features derived from 68Ga-DOTATOC PET/MRI with simultaneous acquisition of apparent diffusion coefficient

“…80 lesions were segmented and the following parameters assessed: SUVmean, SUVstd, SUVmax, COV, TLRE, Entropy log10, Entropy log 2, Volume, Homogeneity. These features were selected based on prior studies showing their predictive value with regards to treatment response and histopathology [41][42][43][44][45].…”