Preoperative Axillary Staging Using 18F-FDG PET/CT and Ultrasonography in Breast Cancer Patients

Purpose: The axillary lymph node status is an important prognostic factor for recurrence and survival of patients who have primary breast cancer. This study determined the accuracy of ultrasonography and F-18-FDG positron emission tomography (PET)/computed tomography (CT) in preoperative staging in axilla in patients with breast cancer. Methods: One hundred seventy-one patients with primary breast cancer were recruited from January 2007 to August 2008. All the patients underwent axillary ultrasonography and F-18-FDG PET/CT for the axillary staging before their operation. Results: The overall sensitivity, specificity, and the positive and negative predictive values and the accuracy of axillary ultrasonography for making the diagnosis of axillary metastasis were 73.07%, 84.87%, 67.85%, 87.82%, and 81.28%, respectively. On a visual assessment of F-18-FDG PET/CT, the diagnostic accuracy was 85.38% with 69.23% sensitivity, 92.43% specificity, a positive predictive value of 80.00%, and a negative predictive value of 87.30%. By the combined use axillary ultrasonography and F-18-FDG PET/CT to the axilla, the sensitivity, specificity, the positive and negative predictive values and the diagnostic accuracy were 82.35%, 97.91%, 93.33%, 94.00%, and 93.84%, respectively. Conclusion: The combination of F-18-FDG PET/CT and ultrasonography improves preoperative axillary staging in breast cancer that are often not found if only one imaging modalities are applied.