RT Journal Article
SR Electronic
T1 Measuring Tumor Cell Proliferation with <sup>18</sup>F-FLT PET During Radiotherapy of Esophageal Squamous Cell Carcinoma: A Pilot Clinical Study
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 528
OP 534
DO 10.2967/jnumed.109.072124
VO 51
IS 4
A1 Jinbo Yue
A1 Lusheng Chen
A1 Alvin R. Cabrera
A1 Xindong Sun
A1 Shuqiang Zhao
A1 Fu Zheng
A1 Anqin Han
A1 Jinsong Zheng
A1 Xuezhong Teng
A1 Li Ma
A1 Yidong Ma
A1 Dali Han
A1 Xianguang Zhao
A1 Dianbin Mu
A1 Jinming Yu
A1 Yuhui Li
YR 2010
UL http://jnm.snmjournals.org/content/51/4/528.abstract
AB The primary aim of this study was to use serial 18F-3′-deoxy-3′-fluorothymidine (FLT) PET/CT to measure tumor cell proliferation during radiotherapy of squamous cell carcinoma (SCC) of the esophagus. Methods: Twenty-one patients with inoperable locally advanced SCC of the esophagus underwent serial 18F-FLT PET/CT during radiotherapy. Each patient received a pretreatment scan, followed by 1–3 scans after delivery of 2, 6, 10, 20, 30, 40, 50, or 60 Gy to the tumor. Results: Among the 19 patients who completed radiotherapy without interruption, parameters reflecting 18F-FLT uptake in the tumor (i.e., maximum tumor standardized uptake value [SUVmax] and proliferation target volume) decreased steadily. All patients demonstrated an almost complete absence of proliferating esophageal tumor after 30 Gy and a complete absence after 40 Gy. In the 2 patients whose radiotherapy course was interrupted, 18F-FLT uptake in the tumor was greater after the interruption than before the interruption. Marked early reduction of 18F-FLT uptake in irradiated bone marrow was observed in all patients, even after only 2 Gy. All showed a complete absence of proliferating marrow in irradiated regions after 10 Gy. Both patients who underwent scans after completing the entire radiotherapy course showed no tumor uptake on 18F-FLT PET/CT but high uptake on 18F-FDG PET/CT. Pathologic examination of these regions revealed inflammatory infiltrates but no residual tumor. Conclusion: 18F-FLT uptake can be used to monitor the biologic response of esophageal SCC and normal tissue to radiotherapy. Increased uptake of 18F-FLT after treatment interruptions may reflect accelerated repopulation. 18F-FLT PET/CT may have an advantage over 18F-FDG PET/CT in differentiating inflammation from tumor.