OBJECTIVE. The purpose of this study was to investigate whether changes in attenuation and size of liver metastatic lesions of colorectal cancer at MDCT 1 month after 90Y radioembolization treatment are predictive of response at FDG PET 3 months after treatment. MATERIALS AND METHODS. Twenty patients with colorectal liver metastasis consecutively treated with 90Y radioembolization underwent triphasic MDCT of the liver at baseline and 1 and 3 months after treatment and FDG PET at baseline and 3 months after treatment. Percentage change in tumor attenuation at MDCT (volumetric attenuation), tumor size at MDCT (according to Response Evaluation Criteria in Solid Tumors [RECIST] and World health Organization [WHO] criteria), and volume-weighted maximum standardized uptake value at FDG PET were evaluated. The correlation between FDG PET response 3 months after treatment and response according to RECIST, WHO criteria, and attenuation 1 month after treatment was evaluated. RESULTS. Only 13.3% of patients with FDG PET findings of response 3 months after treatment were identified according to RECIST and WHO criteria 1 month after treatment. According to attenuation criteria at 1 month, however, 53.3% of patients with an FDG PET response at 3 months were identified. A strong association was found between FDG PET response at 3 months and response based on attenuation criteria (odds ratio, 12.4; 95% CI, 0.58-265.3; p = 0.05). CONCLUSION. Early changes in the attenuation of liver metastatic lesions of colon cancer after 90Y radioembolization treatment may be predictive of future response at FDG PET.
- Colorectal liver metastasis
- FDG PET
- Tumor response
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging