Use of FDG-PET or PET/CT to detect recurrent colorectal cancer in patients with elevated CEA: a systematic review and meta-analysis

The purpose of the present study was to conduct a systematic review and meta-analysis of the published literature to assess the diagnostic performance of FDG-PET or PET/CT in the detection of recurrent colorectal cancer (CRC) rising in patients with elevated CEA. The authors conducted a systematic MEDLINE search of published articles. Two reviewers independently assessed the methodological quality of each study. We estimated pooled sensitivity and specificity and positive and negative likelihood ratios, and summary receiver-operating characteristic curves in the detection of recurrent CRC in patients with elevated CEA. Eleven studies with a total of 510 patients met the inclusion criteria. One hundred and six patients (106/510 = 20.8 %) had true-negative FDG-PET (PET/CT) results in detection of recurrent CRC when rising CEA. The pooled estimates of sensitivity and specificity and positive and negative likelihood ratios of FDG-PET in the detection of tumor recurrence in CRC patients with elevated CEA were 90.3 % (95 % CI, 85.5-94.0 %), 80.0 % (95 % CI, 67.0-89.6 %), 2.88 (95 % CI, 1.37-6.07), and 0.12 (95 % CI, 0.07-0.20), respectively. The pooled estimates of sensitivity and specificity and positive and negative likelihood ratios of FDG-PET/CT in the detection of tumor recurrence in CRC patients with elevated CEA were 94.1 % (95 % CI, 89.4-97.1 %), 77.2 % (95 % CI, 66.4-85.9 %), 4.70 (95 % CI, 0.82-12.13), and 0.06 (95 % CI, 0.03-0.13), respectively. Whole-body FDG-PET and PET/CT are valuable imaging tools for the assessment of patients with suspected CRC tumor recurrence based on the increase of CEA.