Correlations between Tumor to Background Ratio on Breast-Specific Gamma Imaging and Prognostic Factors in Breast Cancer

Abstract

The purpose of this study was to investigate the correlations between tumor-to-background ratio (TBR) obtained from breast-specific gamma imaging (BSGI) and the prognostic factors of breast cancer. Sixty-seven patients with invasive ductal carcinoma who underwent preoperative BSGI were enrolled. The BSGI images were visually scored from 1 to 5 according to a breast imaging reporting and data system (BIRADS). The TBR results obtained from positive BSGI images were compared according to the following prognostic factors: tumor size; axillary lymph node metastasis; nuclear grade (NG); histologic grade (HG); subtype; Ki-67; and the expression profile of estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2). Among 67 images, 60 were classified as a positive finding (sensitivity 89.6%). A higher TBR value was significantly correlated with tumor size ≥ 2 cm (P = 0.001), axillary lymph node metastasis (P = 0.007), high HG (P = 0.029), negative PR status (P = 0.036), and Ki-67 ≥ 14% (P = 0.007). The TBR showed a significant difference between the luminal A and non-luminal A subtypes (P = 0.007). On multivariate analysis, TBR had a high correlation with tumor size ≥ 2 cm, axillary lymph node metastasis, and negative PR status (P = 0.003, 0.048, and 0.030, respectively). A high TBR on BSGI was significantly correlated with poor prognostic factors of breast cancer. Luminal A subtype, a breast cancer subtype with more favorable prognosis, was associated with a low TBR on BSGI.

Unsupervised Clustering Reveals Sarcoidosis Phenotypes Marked by a Reduction in Lymphocytes Relate to Increased Inflammatory Activity on 18FDG-PET/CT

“…Liver mean-SUV uptake was calculated using a volume-of-interest of 3cm 3 from the subject's right hepatic lobe. SUV ratio, shown to be a reliable measure for prognostication and treatment response, and not SUV Max , was utilized to minimize observer variability and standardize PET scan acquisition and reconstruction protocols (33)(34)(35)(36). To maximize specificity of identifying a positive PET scan, lesions with a SUV ratio ≥ 2 were considered positive for inflammatory activity related to sarcoidosis, whereas those with a SUV ratio < 2 were regarded as negative.…”

99mTc-Radiolabeled TPGS Nanomicelles Outperform 99mTc-Sestamibi as Breast Cancer Imaging Agent

“…Since then, 99m Tc-sestamibi has been investigated as a diagnostic probe in several types of cancer, for mammary scintigraphy and parathyroid adenoma imaging [32–36]. The development of new techniques such as breast specific gamma imaging (BSGI) has revalued the usefulness of 99m Tc-sestamibi in oncology field [37–40]. Furthermore, the ability of this radiopharmaceutical to predict or correlate with molecular subtypes of breast cancer has been very recently explored [41].…”