Evaluation of contrast medium enhancement and [18F]-FDG uptake of liver metastasis in PET/CT prior to therapy

ObjectiveTo evaluate the contrast medium enhancement and [18F]-FDG uptake of liver metastases in patients suffering from colon or breast carcinoma prior to therapy.Material and methodsPET/CT (Philips Gemini) with 200 MBq [18F]-FDG and contrast medium was performed in 50 patients with colon and 39 patients with breast carcinoma. Lesions were characterized with the presence or the absence of a rim enhancement. The area size, the HUmean, HUmax, SUVmean, SUVmax of the lesion and of the liver were determined. The standard uptake values (SUVs) were correlated with the tumor markers CEA and CA 15-3.ResultsThe lesions of colon carcinoma had HUmean-values of 70.7 ± 19.2 and of breast carcinoma 88.1 ± 21.7 (p < 0.0001). In breast cancer the SUVmean was 3.9 ± 1.3 versus 4.4 ± 1.9 in colon carcinoma (p = 0.0182). Lesion of colon carcinoma with rim enhancement had a significantly higher SUVmean (4.4 ± 1.5 versus 3.6 ± 1.2; p = 0.001) and SUVmax (6.7 ± 2.6 versus 5.1 ± 2.1; p = 0.000) than lesions without a rim enhancement. A good correlation between tumor markers and SUVsmax could be found in both tumor groups; r = 0.83 (p < 0.01) for colon carcinoma and r = 0.82 (p < 0.01) for breast carcinoma.ConclusionsThe rim enhancement of the lesions in colon carcinoma indicate a significantly higher SUV.