Diagnostic and prognostic value of preoperative ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography for colorectal cancer: comparison with conventional computed tomography

Abstract

Background/Aims18F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) has been used for preoperative staging of colorectal cancer (CRC). However, the diagnostic accuracy of FDG-PET/CT for detection of lymph node or distant metastasis and its prognostic role have not been well established. We therefore evaluated the diagnostic and prognostic value of FDG-PET/CT in comparison with conventional CT for CRC.MethodsWe investigated 220 patients who underwent preoperative FDG-PET/CT and CT, followed by curative surgery for CRC. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of FDG-PET/CT and CT for detection of lymph node metastasis and distant metastasis were evaluated. In addition, we assessed the findings of FDG-PET/CT and CT according to outcomes, including cancer recurrence and cancer-related death, for evaluation of prognostic value.ResultsFor detection of lymph node metastasis, FDG-PET/CT had a sensitivity of 44%, a specificity of 84%, and an accuracy of 67%, compared with 59%, 65%, and 62%, respectively, for CT (P=0.029, P=0.000, and P=0.022). For distant metastasis, FDG-PET/CT had a sensitivity of 79%, a specificity of 94%, and an accuracy of 93%, compared with 79%, 87%, and 86%, respectively, for CT (P=1.000, P=0.004, and P=0.037). In addition, positive findings of lymph node metastasis and distant metastasis on FDG-PET/CT were associated significantly with cancer recurrence or cancer-related death (P=0.009, P=0.001, respectively).ConclusionsPreoperative FDG-PET/CT had a higher specificity and accuracy compared to CT for detection of lymph node metastasis and distant metastasis of CRC. In addition, FDG-PET/CT could be a valuable prognostic tool for CRC.

Tailoring the clinical management of colorectal cancer by 18F-FDG PET/CT

“…However, a plethora of positive lymph nodes tend to be not detected abnormality because of low density, small diameter, regular form and so on (22). Indeed, the overall accuracy of evaluation of N-staging by contrast enhanced CT (ceCT) has been reported merely from 59% to 71% (23,24).…”

Clinical TNM staging for esophageal, gastric, and colorectal cancers in the era of neoadjuvant therapy: A systematic review of the literature

“…For lymph node staging (Table 3B), the sensitivity was found to range from 44% to 73%, and the specificity ranged from 41% to 84%. [84][85][86][87][88][89][90] The accuracies of these studies were around 50%-60%. PET showed a relatively high specificity of 84%, but a sensitivity of only 44%.…”

Preoperative evaluation and indications for pulmonary metastasectomy

“…In many tumor types, FDG-PET/CT showed a higher diagnostic accuracy than PET or CT alone for detecting tumor recurrence. Thus, it is more appropriate to use for patient selection for PM than other conventional imaging modalities (45)(46)(47). Recently, it was reported that dual-time point FDG-PET/CT could be useful for distinguishing primary and metastatic lung adenocarcinoma in patients with SPN (48).…”