18F-FECH PET/CT to Assess Clinically Significant Disease in Prostate Cancer: Correlation With Maximum and Total Cancer Core Length Obtained via MRI-Guided Template Mapping Biopsies

AJR Am J Roentgenol. 2016 Dec;207(6):1297-1306. doi: 10.2214/AJR.15.15679. Epub 2016 Sep 9.

Abstract

Objective: The objective of this study was to detect clinically significant and insignificant prostate cancer on 18F-fluoroethylcholine (FECH) PET/CT and to correlate findings with transperineal template-guided prostate mapping (TPM) biopsy.

Subjects and methods: Fifty-six lobes of the prostate were analyzed in 28 men who underwent FECH PET/CT and TPM. Whole-body images and pelvic images were acquired at 60 and 90 minutes after tracer administration. FECH PET/CT findings were correlated with TPM. Sensitivity, specificity, positive predictive values, negative predictive values, and AUC of dual phase FECH PET/CT were calculated.

Results: Mean age of the patients was 68.8 years (range, 53-79 years), and mean prostate-specific antigen level was 12.1 ng/mL (range, 0.6-45 ng/mL). Mean maximum cancer core length was 4.4 mm (median, 4 mm; range, 1-14 mm) and mean total cancer core length, 14.6 mm (median, 14.6 mm; range, 1-82 mm). Prostate cancer was identified in 38 lobes with a Gleason score of 6 in five lobes (13%), 7 in 27 lobes (71%), 8 in four lobes (11%), and 9 in two lobes (5%). FECH PET/CT showed findings of prostate cancer in 46/56 lobes (82%). The ranges for maximum standardized uptake value for 60- and 90-minute FECH PET/CT were 1.3-11.4 and 1.2-10.9, respectively. Clinically significant cancer was seen in 30 of 38 positive lobes; eight had clinically insignificant disease. For 60-minute imaging, the sensitivity, specificity, and ROC AUC were 75%, 75%, and 0.746 (95% CI, 0.612-0.853). For 90-minute imaging, the sensitivity, specificity, and ROC AUC were 73.7%, 58.3%, and 0.646 (95% CI, 0.498-0.776). Overall sensitivity, specificity, positive predictive value, and negative predictive value were 95%, 50%, 82.6%, and 80%, respectively.

Conclusion: FECH PET/CT can detect prostate cancer and localizes TPM biopsy-proven clinically significant prostate cancer with sensitivity of greater than 89.7%. Of the two imaging durations, 60-minute imaging is more sensitive and specific than 90-minute imaging.

Keywords: MRI; PET/CT; fluoroethylcholine; prostate cancer; template-guided prostate mapping.

Publication types

  • Comparative Study
  • Evaluation Study
  • Validation Study

MeSH terms

  • Aged
  • Choline / analogs & derivatives*
  • Humans
  • Image-Guided Biopsy / methods*
  • Magnetic Resonance Imaging, Interventional / methods*
  • Male
  • Middle Aged
  • Neoplasm Grading
  • Neoplasm Invasiveness
  • Observer Variation
  • Pilot Projects
  • Positron Emission Tomography Computed Tomography / methods*
  • Prostatic Neoplasms / diagnostic imaging
  • Prostatic Neoplasms / pathology*
  • Reproducibility of Results
  • Sensitivity and Specificity
  • Statistics as Topic
  • Tumor Burden

Substances

  • fluoroethylcholine
  • Choline