Comparison of [11 C]choline Positron Emission Tomography With T2- and Diffusion-Weighted Magnetic Resonance Imaging for Delineating Malignant Intraprostatic Lesions

• Published in: International journal of radiation oncology, biology, physics Vol. 92; no. 2; pp. 438 - 445
• Main Authors: Chang, Joe H., MBChB, Lim Joon, Daryl, FRANZCR, Davis, Ian D., MBBS, PhD, Lee, Sze Ting, FRACP, Hiew, Chee-Yan, FRANZCR, Esler, Stephen, FRANZCR, Gong, Sylvia J., PhD, Wada, Morikatsu, FRANZCR, Clouston, David, MBBS, PhD, O'Sullivan, Richard, FRANZCR, Goh, Yin P., MBBS, Bolton, Damien, MD, Scott, Andrew M., MD, Khoo, Vincent, MD
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01-06-2015
• Subjects: Adult; Aged; Analysis of Variance; BIOMEDICAL RADIOGRAPHY; CALORIMETRY; CARBON 11; Carbon Radioisotopes; CHOLINE; COMPARATIVE EVALUATIONS; DIFFUSION; Diffusion Magnetic Resonance Imaging - methods; Fluorodeoxyglucose F18; GLANDS; Hematology, Oncology and Palliative Medicine; Humans; Magnetic Resonance Imaging - methods; Male; Middle Aged; Multimodal Imaging - methods; NEOPLASMS; NMR IMAGING; POSITRON COMPUTED TOMOGRAPHY; Positron-Emission Tomography - methods; Prostate - diagnostic imaging; Prostate - pathology; Prostate-Specific Antigen - blood; Prostatic Neoplasms - diagnosis; Prostatic Neoplasms - diagnostic imaging; Prostatic Neoplasms - pathology; Prostatic Neoplasms - surgery; RADICALS; Radiology; RADIOLOGY AND NUCLEAR MEDICINE; Radiopharmaceuticals; Reference Standards; SENSITIVITY; Sensitivity and Specificity; SPECIFICITY; THERAPY; Tumor Burden; UPTAKE; ZONES
• ISSN: 0360-3016; 1879-355X
• DOI: 10.1016/j.ijrobp.2015.02.004

Purpose The purpose of this study was to compare the accuracy of [11 C]choline positron emission tomography (CHOL-PET) with that of the combination of T2-weighted and diffusion-weighted (T2W/DW) magnetic resonance imaging (MRI) for delineating malignant intraprostatic lesions (IPLs) for guiding focal therapies and to investigate factors predicting the accuracy of CHOL-PET. Methods and Materials This study included 21 patients who underwent CHOL-PET and T2W/DW MRI prior to radical prostatectomy. Two observers manually delineated IPL contours for each scan, and automatic IPL contours were generated on CHOL-PET based on varying proportions of the maximum standardized uptake value (SUV). IPLs identified on prostatectomy specimens defined reference standard contours. The imaging-based contours were compared with the reference standard contours using Dice similarity coefficient (DSC), and sensitivity and specificity values. Factors that could potentially predict the DSC of the best contouring method were analyzed using linear models. Results The best automatic contouring method, 60% of the maximum SUV (SUV60 ) , had similar correlations (DSC: 0.59) with the manual PET contours (DSC: 0.52, P =.127) and significantly better correlations than the manual MRI contours (DSC: 0.37, P <.001). The sensitivity and specificity values were 72% and 71% for SUV60 ; 53% and 86% for PET manual contouring; and 28% and 92% for MRI manual contouring. The tumor volume and transition zone pattern could independently predict the accuracy of CHOL-PET. Conclusions CHOL-PET is superior to the combination of T2W/DW MRI for delineating IPLs. The accuracy of CHOL-PET is insufficient for gland-sparing focal therapies but may be accurate enough for focal boost therapies. The transition zone pattern is a new classification that may predict how well CHOL-PET delineates IPLs.