The Application Of PET/CT In The Postoperative Follow-up Of The Colorectal Cancer

Purpose:To study the value of ¹⁸F-FDG PET/CT in diagnosis of the recurrence in colorectal cancer by prospective method.Materials and methods:Sixty-four cases of colorectal cancer with clinical recurrence or metastasis accepted ¹⁸F-FDG PET/CT scan.The consistency,sensitivity,speciality,positive predictive value and negative predictive value in local recurrence,lymph node metastasis,liver metastasis,lung metastasis bone metastasis,and et al.were calculated and compared with single CT,PET and CEA respectively.Synthetically analyze the PET,CT and tomographic fusion.Standard uptake value (SUV)was the semi quantitative criterion in PET.Abnormal irradiative accumulation was define as SUVmax＞2.5.The single PET and CT came from the PET/CT tomography,enhanced CT was performed if needed. CEA value must be measured in two weeks before and after PET/CT. Results:The acurracy,sensitivity,speciality,positive predictive value and negative predictive value of ¹⁸F-FDG PET/CT was 90.63 %,90.63%,90.91%,95.24%,81.82%respectively.The result of single CT was 67.19%,63.64%,75.00%,84.85%,48.39%respectively.And 64.06%,68.18%,55%,76.92%,44.00%in CEA.Twenty cases were disease-free,5cases were anastomotic recurrence.Single metastasis was found in 10 cases and multiple or diffused metastasis in 32 cases.Of these cases,10 cases were hepatic metastasis,11 cases were lung metastasis,7 cases were abdomen metastasis,9 cases were bone metastasis,4 cases were ovary metastasis,2 cases were pelvic metastasis, 2 cases were incision metastasis,1 case was vaginal metastasis,and 15 cases were lymph node metastasis.Conclusion:The diagnostic value of ¹⁸F -FDG PET/CT in recurrence and metastasis in colorectal cancer was much better than single CT,CEA,and PET.The site of metastasis was liver,lung,bone, abdomen and lymph nodes;ovary was one of the most common metastatic organs in woman patients.