Value of PET-FDG in primary breast cancer based on histopathological and immunohistochemical prognostic factors

Abstract

Background: The aim of the study was to analyze in breast tumors the correlation between [(18)F]fluorodeoxyglucose (FDG) uptake assessed by positron emission tomography (PET) and histopathological and immunohistochemical prognostic factors.

Methods: FDG-PET combined with computed tomography (CT) was performed before surgery in 45 women with biopsy-proven primary breast cancer. The standardized uptake value (SUV) was compared with histopathological findings after surgery.

Results: A positive relationship was found between SUV and histological grade (p < 0.0001), histological type (p = 0.001), tumor size (p < 0.0435), estrogen receptor status (p < 0.0005), and progesterone receptor status (p = 0.002). FDG-PET/CT revealed unknown distant metastatic lesions in 2 of 12 patients with triple-negative breast cancer. The sensitivity of FDG-PET/CT for detecting axillary lymph node metastases was, respectively, 21% and 100% for pN1 and pN2 cases, whereas specificity was 100% for pN0.

Conclusion: SUV, a preoperative and noninvasive metabolic parameter, correlates with other known prognostic factors in breast cancer. This study provides valuable insight into the usefulness of FDG-PET/CT for preoperative staging of patients with triple-negative and poorly differentiated breast tumors but not for evaluating axillary lymph nodes and lobular carcinomas.