Oncology, Imperial College, London.
To evaluate the accuracy and biological basis for [11C] choline-PET-CT in the nodal staging of high risk localised prostate cancer patients.
Twenty eight patients underwent dynamic [11C] choline-PET-CT of the pelvis and lower abdomen prior to extended laparoscopic pelvic lymph node dissection (eLPL). The sensitivity and specificity of [11C]choline PET, [11C]choline PET-CT and MRI for nodal detection were calculated. Average and maximal standardized Uptake Values (SUVave, SUVmax) were compared with choline kinase alpha (CHKα) and Ki67 immunohistochemistry scores.
406 lymph nodes, in 26 patients, were assessable. 27 (6.7%) involved pelvic nodes at eLPL were detected in 9 patients. 17 out of the 27 involved nodes were sub-centimetre. The sensitivity and specificity on a per nodal basis were 18.5 % and 98.7%, 40.7% and 98.4 %, and 51.9% and 98.4% for MRI, [11C]choline PET and [11C]choline PET-CT, respectively. Sensitivity was higher for [11C]choline PET-CT compared with MRI (p=0.007). A higher nodal detection rate, including sub-centimetre nodes, was seen with [11C]choline PET-CT than MRI. Malignant lesions showed CHKα expression in both cytoplasm and nucleus. SUVave and SUVmax strongly correlated with CHKα staining intensity (r=0.68, p<0.0001 and r=0.63, p=0.0004, respectively). In contrast, Ki67 expression was generally low in all tumors.
This study establishes the relationship between [11C]choline PET- CT uptake with choline kinase expression in prostate cancer and allows it to be used as a non-invasive means of staging pelvic lymph nodes, being highly specific and more sensitive than MRI including the detection of sub-centimetre disease.
Written by:
Contractor KB, Challapalli A, Barwick T, Winkler M, Hellawell G, Hazell S, Tomasi G, Al-Nahhas A, Mapelli P, Kenny L, Tadrous P, Coombes RC, Aboagye EO, Mangar S. Are you the author?
Reference: Clin Cancer Res. 2011 Oct 28. Epub ahead of print.
doi: 1158/1078-0432.CCR-11-2048
PubMed Abstract
PMID: 22038995
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