The role of FDG-PET for preoperative evaluation of regional lymph node metastases in locally advanced breast cancer.

Abstract

Abstract Abstract #4021 Backgound: The aim of this study was to evaluate the role of FDG-PET in detecting regional lymph node metastases in locally advanced breast cancer.
 Methods: FDG-PET was performed in 114 women with locally advanced breast cancer. Among them, 7 were with primary tumor larger than 5cm, 18 were with inflammatory breast cancer, and 89 were with clinically palpable axillary lymph node metastases. FDG uptakes of axillary, internal mammary, and supraclavicular lymph node were correlated by comparing pathologic and radiographic findings.
 Results: The sensitivity, specificity, and positive predictive value of FDG-PET for detection of axillary lymph node metastases in 83 patients who did not receive neoadjuvant chemotherapy were 91%, 33.3 % and 94.7% respectively. Among the 83 patients, 4 were with false-negative and 6 were with false-positive. Those for detection of axillary lymph node metastases in 12 patients who received neoadjuvant chemotherapy were 55.6%, 100%, and 100% respectively, and 4 of them were with false-negative and no one was with false-positive results. The sensitivity and positive predictive value of combined assessment of clinical examination and ultrasound scan on axillary node metastases were 92.1% and 93.3% in 81 patients. Those of combined assessment of clinical examination, ultrasound scan, and PET were 100% and 95.7% in 69 patients. FDG uptake in internal mammary node was seen in 14 out of 114 patients (12.2%). The positive predictive value of FDG-PET for detection of internal mammary metastases in 9 patients with pathologic confirmation was 75%. 6 of them were with true-positive, 2 were with false-positive, and 1 was false-negative. Among the 6 true positive patients, 3 were not detected internal mammary metastases in ultrasound scan. FDG uptake in the supraclavicular node was seen in 22 out of 114 patients (19.2%). The positive predictive value of FDG-PET for detection of supraclavicular metastases in 12 patients with pathologic confirmation was 58.3%. 7 of them were with true –positive and 5 were with false-positive. 1 of 7 true-positive patients was not detected supraclavicular lymph node metastases in ultrasound scan.
 Conclusions: The sensitivity of FDG-PET for detection of axillary lymph node metastases was higher than that of FDG-PET for detection of internal mammary or supraclavicular lymph node. The addition of FDG-PET to standard work-up of locally advanced breast cancer patients could provide a more precise evaluation of regional lymph node metastases. Positive combined assessment of clinical examination, ultrasound scan and PET on axillary node metastases also could be an indication for full ALND without SNB. Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 4021.