Comparative study of the value of dual tracer PET/CT in evaluating breast cancer

The present study was conducted to assess the relationship between tumor uptake and pathologic findings using dual-tracer PET/computed tomography (CT) in patients with breast cancer. Seventy-four patients with breast cancer (mean age 54 similar to years) who underwent 11C-choline and 2-[18F]fluoro-2-deoxy-d-glucose (18F-FDG) PET/CT prior to surgery on the same day were enrolled in the present study. Images were reviewed by a board-certified radiologist and two nuclear medicine specialists who were unaware of any clinical information and a consensus was reached. Uptake patterns and measurements of dual tracers were compared with the pathologic findings of resected specimens as the reference standard. Mean (+/- SD) tumor size was 5.9 +/- 3.2 similar to cm. All primary tumors were identified on 18F-FDG PET/CT and 11C-choline PET/CT. However, 18F-FDG PET/CT demonstrated focal uptake of the primary tumor with (n=38; 51%) or without (n=36; 49%) diffuse background breast uptake. Of the pathologic findings, multiple logistic regression analysis revealed an independent association between fibrocystic change and diffuse background breast uptake (odds ratio [OR] 8.57; 95% confidence interval [CI] 2.8625.66; P<0.0001). Tumors with higher histologic grade, nuclear grade, structural grade, nuclear atypia, and mitosis had significantly higher maximum standardized uptake values (SUVmax) and tumor-to-background ratios (TBR) for both tracers. Multiple logistic regression analysis revealed that only the degree of mitosis was independently associated with a high SUVmax (OR 7.45; 95%CI 2.2125.11; P=0.001) and a high TBR (OR 5.41; 95%CI 1.1325.96; P=0.035) of 11C-choline PET/CT. In conclusion, 11C-choline may improve tumor delineation and reflect tumor aggressiveness on PET/CT in patients with breast cancer.