European Urology

Abstract

Background

Current imaging techniques are of limited value for lymph node (LN) staging in bladder cancer (BCa) patients scheduled for radical cystectomy (RC).

Objective

Evaluate the diagnostic efficacy of [11C]choline positron emission tomography in combination with computed tomography (PET/CT) for LN staging of patients with BCa scheduled for RC and compare that efficacy with the diagnostic efficacy of CT and the gold standard of histopathologic evaluation.

Design, setting, and participants

From June 2004 to May 2007, 44 patients with localized BCa were staged with [11C]choline PET with low-dose CT for attenuation correction and simultaneous intravenous and rectal contrast-enhanced diagnostic CT before RC and pelvic lymph node dissection (PLND). LNs were dissected from the internal and external iliac arteries up to the origin of the inferior mesentery artery according to a template with 14 predefined anatomic fields.

Intervention

Diagnostic [11C]choline PET/CT before RC and regional LN dissection.

Measurements

Histopathologic findings of resected LN were correlated with the results of [11C]choline PET/CT and CT alone in a patient- and field-based manner. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of [11C]choline PET/CT and CT were assessed.

Results and limitations

LN metastases were found in 12 of 44 patients (27%). On patient-based analysis, sensitivity, specificity, PPV, NPV, and accuracy for [11C]choline PET/CT were calculated as 58%, 66%, 39%, 81%, and 64%, respectively; and for CT the calculated percentages were 75%, 56%, 39%, 86%, and 61%, respectively. Twenty-five of 471 dissected LN fields (5%) showed metastases. On field-based analysis, sensitivity, specificity, PPV, NPV, and accuracy for [11C]choline PET/CT were 28%, 95%, 21%, 96%, and 91%, respectively; for CT, the calculated percentages were 39%, 92%, 20%, 96%, and 90%, respectively. Limitations of this study are small patient number and the fact that not all patients underwent extensive PLND.

Conclusions

In patients with BCa who were scheduled for RC, preoperative LN staging with [11C]choline PET/CT was not able to improve diagnostic efficacy compared with conventional CT alone.