11C-choline positron emission tomography/computerized tomography for preoperative lymph-node staging in intermediate-risk and high-risk prostate cancer: comparison with clinical staging nomograms

Eur Urol. 2008 Aug;54(2):392-401. doi: 10.1016/j.eururo.2008.04.030. Epub 2008 Apr 18.

Abstract

Background: Conventional imaging (CI) techniques are inadequate for lymph node (LN) staging in prostate cancer (PCa).

Objectives: To assess the accuracy of (11)C-Choline positron emission tomography/computerized tomography (PET/CT) for LN staging in intermediate-risk and high-risk PCa and to compare it with two currently used nomograms.

Design, setting, and participants: From January 2007 to September 2007, 57 PCa patients at intermediate risk (n=27) or high risk (n=30) were enrolled at two academic centres. All patients underwent preoperative PET/CT and radical prostatectomy with extended pelvic LN dissection (PLND). Risk of LN metastasis (LNM) was assessed using available nomograms.

Measurements: Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and number of correctly recognized cases for LNM detection at PET/CT were assessed. The accuracy of PET/CT for LNM detection was compared with the accuracy of nomograms for LNM prediction by using receiver operating characteristic (ROC) analysis.

Results and limitations: Fifteen patients (26%) had LNMs, and a total of 41 LNMs were identified. On a patient analysis, sensitivity, specificity, PPV, NPV, and number of correctly recognized cases at PET/CT were 60.0%, 97.6%, 90.0%, 87.2%, and 87.7% while, on node analysis, these numbers were 41.4%, 99.8%, 94.4%, 97.2%, and 97.1%. The mean diameter (in mm) of the metastatic deposit of true-positive LNs was significantly higher than that of false-negative LNs (9.2 vs 4.2; p=0.001). PET/CT showed higher specificity and accuracy than the nomograms; however, in pairwise comparison, the areas under the curve (AUCs) were not statistically different (all p values >0.05).

Conclusions: In patients with intermediate-risk and high-risk PCa, (11)C-Choline PET/CT has quite a low sensitivity for LNM detection but performed better than clinical nomograms, with equal sensitivity and better specificity.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Carbon Radioisotopes*
  • Choline*
  • Humans
  • Lymphatic Metastasis
  • Male
  • Middle Aged
  • Neoplasm Staging
  • Nomograms*
  • Positron-Emission Tomography*
  • Preoperative Care
  • Prostatic Neoplasms / diagnostic imaging*
  • Prostatic Neoplasms / pathology*
  • Prostatic Neoplasms / surgery
  • Reproducibility of Results
  • Risk Assessment
  • Tomography, X-Ray Computed*

Substances

  • Carbon Radioisotopes
  • Choline