Imaging early changes in proliferation at 1 week post chemotherapy: a pilot study in breast cancer patients with 3'-deoxy-3'-[18F]fluorothymidine positron emission tomography

Eur J Nucl Med Mol Imaging. 2007 Sep;34(9):1339-47. doi: 10.1007/s00259-007-0379-4. Epub 2007 Mar 2.


Purpose: 3'-deoxy-3'-[18F]fluorothymidine positron emission tomography ([18F]FLT-PET) has been developed for imaging cell proliferation and findings correlate strongly with the Ki-67 labelling index in breast cancer. The aims of this pilot study were to define objective criteria for [18F]FLT response and to examine whether [18F]FLT-PET can be used to quantify early response of breast cancer to chemotherapy.

Methods: Seventeen discrete lesions in 13 patients with stage II-IV breast cancer were scanned prior to and at 1 week after treatment with combination 5-fluorouracil, epirubicin and cyclophosphamide (FEC) chemotherapy. The uptake at 90 min (SUV90) and irreversible trapping (Ki) of [18F]FLT were calculated for each tumour. The reproducibility of [18F]FLT-PET was determined in nine discrete lesions from eight patients who were scanned twice before chemotherapy. Clinical response was assessed at 60 days after commencing FEC.

Results: All tumours showed [18F]FLT uptake and this was reproducible in serial measurements (SD of mean % difference=10.5% and 15.1%, for SUV90 and Ki, respectively; test-retest correlation coefficient>or=0.97). Six patients had a significant clinical response (complete or partial) at day 60; these patients also had a significant reduction in [18F]FLT uptake at 1 week. Decreases in Ki and SUV90 at 1 week discriminated between clinical response and stable disease (p=0.022 for both parameters). In three patients with multiple lesions there was a mixed [18F]FLT response in primary tumours and metastases. [18F]FLT response generally preceded tumour size changes.

Conclusion: [18F]FLT-PET can detect changes in breast cancer proliferation at 1 week after FEC chemotherapy.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Antineoplastic Agents / therapeutic use*
  • Antineoplastic Combined Chemotherapy Protocols / therapeutic use
  • Breast Neoplasms / diagnosis
  • Breast Neoplasms / drug therapy*
  • Breast Neoplasms / pathology*
  • Cell Proliferation
  • Cyclophosphamide / administration & dosage
  • Dideoxynucleosides / pharmacology*
  • Epirubicin / administration & dosage
  • Female
  • Fluorouracil / administration & dosage
  • Humans
  • Ki-67 Antigen / biosynthesis
  • Kinetics
  • Middle Aged
  • Neoplasm Metastasis
  • Positron-Emission Tomography / methods*
  • Treatment Outcome


  • Antineoplastic Agents
  • Dideoxynucleosides
  • Ki-67 Antigen
  • Epirubicin
  • Cyclophosphamide
  • alovudine
  • Fluorouracil