A systematic review and meta-analysis of pretherapeutic lymph node staging of colorectal cancer by 18F-FDG PET or PET/CT.

The purpose of the present study was to conduct a systematic review and meta-analysis of the published literature to evaluate the diagnostic performance of fluorine-18 2-fluoro-2-deoxy-D-glucose (18F-FDG) PET in the pretherapeutic assessment of nodal staging in patients with colorectal cancer (CRC). We conducted a systematic MEDLINE search of articles in the published literature (last update, February 2012). Two reviewers independently assessed the methodological quality of each study. We estimated pooled sensitivity, specificity, summary receiver operating characteristic curves, and summary likelihood ratios. A total of 409 patients from 10 studies were analyzed. The pooled estimates of sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of 18F-FDG PET [PET/computed tomography (CT)] in the detection of pretherapeutic lymph node involvement in patients with CRC were 42.9% [95% confidence interval (CI): 36.0-50.0%], 87.9% (95% CI: 82.6-92.0%), 2.82 (95% CI: 1.96-4.07), and 0.69 (95% CI: 0.62-0.78), respectively. There is no solid evidence to support the routine clinical application of 18F-FDG PET (PET/CT) in the pretherapeutic evaluation of lymph node status in patients with CRC. However, 18F-FDG PET (PET/CT) could be used to strengthen the possibility of suspected metastatic lymph nodes detected by other imaging modalities.