The clinical value of PET/CT in the early detection of cea rising which is caused by recurrence or metastasis after the surgical rectal cancer

Objective: To investigate the clinical value of PET/CT in the early detection of CEA rising which is caused by pelvic recurrence or metastasis after the surgical removal of rectal cancer. Methods: A total of 64 rectal cancer patients who underwent the surgical removal of rectal cancer and common recheck CEA (which are higher three times than normal) were included. All of the patients were enrolled for whole body PET/CT scan and confirmed by a series of examination or clinical follow-up. The time of follow-up is from 3 months to 14 months, the mean time is 6 months. Results: Of the 64 patients, 45 were confirmed to have recurrent in the pelvic or metastasis lesions, 19 were confirmed to have no recurrent or metastasis lesions. Of the 47 patients which is diagnosis the recurrent or metastasis by PET/CT, 4 is false positive. The diagnostic accuracy of PET/CT were 95.6% (43/45) for sensitivity, 78.9% (15/19) for specificity, 91.5% (43/47) for positive predictive value, 88.2% (15/17) for Negative predictive value. The diagnostic accuracy of CT were 82.2% (37/45) for sensitivity, 84.2% (16/19) for specificity, 86.0% (37/43) for positive predictive value, 50.0% (16/32) for Negative predictive value. Of the 24 patients which is diagnosis normal by CT, 7 patients is detected recurent or metastasis by PET/CT. Conclusion: PET/CT is an accurate technique in the early detection of pelvic recurrence or metastasis after surgical removal of rectal cancer. (authors)