Journal of Clinical Oncology, 2006 ASCO Annual Meeting Proceedings (Post-Meeting Edition).
Vol 24, No 18S (June 20 Supplement), 2006: 613
© 2006 American Society of Clinical Oncology

This Article Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Download to citation manager Rights & Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Kenny, L. M. Articles by Aboagye, E. Search for Related Content PubMed Articles by Kenny, L. M. Articles by Aboagye, E.

Abstract

A feasibility study of [¹¹C]choline for the molecular imaging of human breast cancer in vivo using positron emission tomography (PET)

Imperial College London, London, United Kingdom; Hammersmith Hospitals NHS Trust, London, United Kingdom; Hammersmith Imanet, London, United Kingdom

613

Background: [¹¹C]Choline is a novel PET radiotracer. Preclinical studies suggest that it may be promising in breast cancer. [¹¹C]Choline has been recently evaluated as a screening agent in prostate cancer, but no studies have yet investigated its potential in breast cancer. We report a pilot study evaluating the utility and reproducibility of [¹¹C]Choline-PET in breast cancer. Methods: Dynamic imaging was performed on an ECAT962 HR+ PET scanner for 65 min after intravenous injection with 190–369 MBq [¹¹C]choline. Patients with locally advanced and metastatic breast cancer were eligible. All histological subtypes were included (ductal, lobular, and inflammatory). Arterial blood samples were taken continuously for 10 min, with 8 discrete samples up to 60 min to measure [¹¹C]choline and metabolites. Tissue uptake was determined by standardised uptake value at 60 min (SUV, dose and BSA corrected) and Ki (irreversible trapping) calculated using Patlak (corrected for [¹¹C]choline metabolites in plasma) and modified Patlak analysis (corrected for plasma + tissue metabolites). Reproduciblilty scans were performed 2–17 days later in the absence of treatment. Results: Tumour [¹¹C]choline uptake was observed in 10 out of 11 patients (12 out of 13 distinct lesions). There was a significant difference between tumour and normal tissue (breast/lung) in [¹¹C]choline uptake for Ki (p<0.0001) and SUV (p<0.0001). Tissue uptake was of the order lung normal breast < tumour < liver spleen. [¹¹C]choline was rapidly metabolised, at 60 min the mean ± S.E. plasma radioactivity due to [¹¹C]choline was 16.4 ± 2.9%. [¹¹C]Choline uptake was found to be reproducible for Ki (modified Patlak: r=0.93, p<0.0001, Patlak: r=0.85, p=0.002) and SUV (r=0.94, p<0.0001) - measured in 8 patients (median of 2 days after the 1^st scan). Tumour Patlak Ki was 13.2% > Ki calculated using modified Patlak analysis. Conclusions: [¹¹C]Choline-PET imaging of breast cancer is promising and warrants further evaluation. Tumour [¹¹C]Choline uptake measured by Ki and SUV is reproducible. We plan to study the relationship between choline uptake measured by PET and immunoassays of tumour samples. Functional imaging could have a vital role to determine the efficacy of target-specific agents.

No significant financial relationships to disclose.

Abstract presentation from the 2006 ASCO Annual Meeting