RT Journal Article
SR Electronic
T1 Quantitative Analysis of Response to Treatment with Erlotinib in Advanced Non–Small Cell Lung Cancer Using <sup>18</sup>F-FDG and 3′-Deoxy-3′-<sup>18</sup>F-Fluorothymidine PET
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 1871
OP 1877
DO 10.2967/jnumed.111.094458
VO 52
IS 12
A1 Deniz Kahraman
A1 Matthias Scheffler
A1 Thomas Zander
A1 Lucia Nogova
A1 Adriaan A. Lammertsma
A1 Ronald Boellaard
A1 Bernd Neumaier
A1 Roland T. Ullrich
A1 Arne Holstein
A1 Markus Dietlein
A1 Jürgen Wolf
A1 Carsten Kobe
YR 2011
UL http://jnm.snmjournals.org/content/52/12/1871.abstract
AB The purpose of this study was to evaluate the relevance for the prediction of clinical benefit of first-line treatment with erlotinib using different quantitative parameters for PET with both 18F-FDG and 3′-deoxy-3′-18F-fluorothymidine (18F-FLT) in patients with advanced non–small cell lung cancer. Methods: Data were used from a prospective trial involving patients with untreated stage IV non–small cell lung cancer. 18F-FDG PET and 18F-FLT PET were performed before and 1 (early) and 6 (late) weeks after erlotinib treatment. Several quantitative standardized uptake values (SUVs) using different definitions of volumes of interest with varying isocontours (maximum SUV [SUVmax], 2-dimensional peak SUV [SUV2Dpeak], 3-dimensional [3D] peak SUV [SUV3Dpeak], 3D isocontour at 50% of the maximum pixel value [SUV50], 3D isocontour at 50% adapted for background [SUVA50], 3D isocontour at 41% of the maximum pixel value adapted for background [SUVA41], 3D isocontour at 70% of the maximum pixel value [SUV70], 3D isocontour at 70% adapted for background [SUVA70], and relative SUV threshold level [SUVRTL]) and metabolically active volume measurements were obtained in the hottest single tumor lesion and in the sum of up to 5 lesions per scan in 30 patients. Metabolic response was defined as a minimum reduction of 30% in each of the different SUVs and as a minimum reduction of 45% in metabolically active volume. Progression-free survival (PFS) was compared between patients with and without metabolic response measured with each of the different parameters, using Kaplan–Meier statistics and a log-rank test. Results: Patients with a metabolic response on early 18F-FDG PET and 18F-FLT PET in the hottest single tumor lesion as well as in the sum of up to 5 lesions per scan had a significantly longer PFS, regardless of the method used to calculate SUV. However, the highest significance was obtained for SUVmax, SUV50, SUVA50, and SUVA41. Patients with a metabolic response measured by SUVmax and SUV3Dpeak on late 18F-FDG PET in the hottest single tumor lesion had a significantly longer PFS. Furthermore, Kaplan–Meier analyses showed a strong association between PFS and response seen by metabolically active volume, measured either in early 18F-FLT or in late 18F-FDG. Conclusion: Early 18F-FDG PET and 18F-FLT PET can predict PFS regardless of the method used for SUV calculation. However, SUVmax, SUV50, SUVA50, and SUVA41 measured with 18F-FDG might be the best robust SUV to use for early response prediction. Metabolically active volume measurement in early 18F-FLT PET and late 18F-FDG PET may have an additional predictive value in monitoring response in patients with advanced non–small cell lung cancer treated with erlotinib.