The clinical impact of FDG PET/CT in patients with pulmonary metastasis from colorectal cancer

1716 Objectives: PET/CT is widely applied in oncology and reinforcing the role of PET. In the present study, we evaluated the value of PET/CT in assessing the operability of pulmonary metastasis from colorectal cancer. Methods: Whole body FDG PET/CT was performed to assess the operability in 38 patients (M:F = 26:12, age: 61 ± 10 years) with suspicious pulmonary metastasis in enhanced chest CT. The findings of PET/CT and chest CT were compared and correlated with the pathologic findings in 24 patients and with clinical follow-up in the rest 14 conservatively managed cases following up for more than 6 months. First only PET images from the PET/CT studies were interpreted. Independently, combined PET/CT images were interpreted. The results of PET alone and PET/CT were compared. Results: The findings of PET/CT revealed pulmonary metastasis without other organ metastasis in 21 patients, and did not make any change in the initial treatment plan. FDG PET/CT from 8 patients showed no evidence of pulmonary metastasis. Nine patients had metastasis in other organs and were directed to non-surgical plan. One patient could not undergo wedge resection due to poor general condition. Overall 47% of patients had to change the original plan based on CT findings. Total 72 lesions were found in PET/CT image and 56 lesions were true metastasis, confirmed by resection or follow-up studies. When only PET images were reviewed, sensitivity and specificity were 100% and 43%. When combined, the sensitivity and specificity of PET/CT were 95% and 100%. Conclusions: FDG PET/CT had guided the management plan correctly in almost half of patients with pulmonary metastasis from colorectal cancer. PET/CT improved the lower specificity of PET. Using FDG PET/CT, there would be more accurate selection of patient for resection of pulmonary metastasis from colorectal cancer.