Imaging of treatment response to the combination of carboplatin and paclitaxel in human ovarian cancer xenograft tumors in mice using FDG and FLT PET

TY - JOUR

T1 - Imaging of treatment response to the combination of carboplatin and paclitaxel in human ovarian cancer xenograft tumors in mice using FDG and FLT PET

AU - Munk Jensen, Mette

AU - Erichsen, Kamille Dumong

AU - Björkling, Fredrik

AU - Madsen, Jacob

AU - Jensen, Peter Buhl

AU - Sehested, Maxwell

AU - Højgaard, Liselotte

AU - Kjær, Andreas

PY - 2013/2/26

Y1 - 2013/2/26

N2 - Introduction: A combination of carboplatin and paclitaxel is often used as first line chemotherapy for treatment of ovarian cancer. Therefore the use of imaging biomarkers early after initiation of treatment to determine treatment sensitivity would be valuable in order to identify responders from non-responders. In this study we describe the noninvasive PET imaging of glucose uptake and cell proliferation using 2-deoxy-2-[18F]fluoro-D-glucose (FDG) and 3′-deoxy-3′-[18F]fluorothymidine (FLT) for early assessment of treatment response in a pre-clinical mouse model of human ovarian cancer treated with carboplatin and paclitaxel. Methods: In vivo uptake of FLT and FDG in human ovarian cancer xenografts in mice (A2780) was determined before treatment with carboplatin and paclitaxel (CaP) and repeatedday 1, 4 and 8 after treatment start. Tracer uptake was quantified using small animal PET/CT. Tracer uptake was compared with gene expression of Ki67, TK1, GLUT1, HK1 and HK2. Results: Tumors in the CaP group was significantly smaller than in the control group (p=0.03) on day 8. On day 4 FDG SUVmax ratio was significantly lower in the CaP group compared to the control group (105±4% vs 138±9%; p=0.002) and on day 8 the FDG SUVmax ratio was lower in the CaP compared to the control group (125±13% vs 167±13%; p=0.05). On day 1 the uptake of FLT SUVmax ratio was 89±9% in the CaP group and 109±6% in the control group; however the difference was not statistically significant (p=0.08). Conclusions: Our data suggest that both FDG and FLT PET may be used for the assessment of anti-tumor effects of a combination of carboplatin and paclitaxel in the treatment of ovarian cancer. FLT provides an early and transient signal and FDG a later and more prolonged response. This underscores the importance of optimal timing between treatment and FLT or FDG imaging since treatment response may otherwise be overlooked.

AB - Introduction: A combination of carboplatin and paclitaxel is often used as first line chemotherapy for treatment of ovarian cancer. Therefore the use of imaging biomarkers early after initiation of treatment to determine treatment sensitivity would be valuable in order to identify responders from non-responders. In this study we describe the noninvasive PET imaging of glucose uptake and cell proliferation using 2-deoxy-2-[18F]fluoro-D-glucose (FDG) and 3′-deoxy-3′-[18F]fluorothymidine (FLT) for early assessment of treatment response in a pre-clinical mouse model of human ovarian cancer treated with carboplatin and paclitaxel. Methods: In vivo uptake of FLT and FDG in human ovarian cancer xenografts in mice (A2780) was determined before treatment with carboplatin and paclitaxel (CaP) and repeatedday 1, 4 and 8 after treatment start. Tracer uptake was quantified using small animal PET/CT. Tracer uptake was compared with gene expression of Ki67, TK1, GLUT1, HK1 and HK2. Results: Tumors in the CaP group was significantly smaller than in the control group (p=0.03) on day 8. On day 4 FDG SUVmax ratio was significantly lower in the CaP group compared to the control group (105±4% vs 138±9%; p=0.002) and on day 8 the FDG SUVmax ratio was lower in the CaP compared to the control group (125±13% vs 167±13%; p=0.05). On day 1 the uptake of FLT SUVmax ratio was 89±9% in the CaP group and 109±6% in the control group; however the difference was not statistically significant (p=0.08). Conclusions: Our data suggest that both FDG and FLT PET may be used for the assessment of anti-tumor effects of a combination of carboplatin and paclitaxel in the treatment of ovarian cancer. FLT provides an early and transient signal and FDG a later and more prolonged response. This underscores the importance of optimal timing between treatment and FLT or FDG imaging since treatment response may otherwise be overlooked.

U2 - 10.1371/journal.pone.0085126

DO - 10.1371/journal.pone.0085126

M3 - Journal article

C2 - 24386456

SN - 1932-6203

VL - 8

JO - P L o S One

JF - P L o S One

IS - 12

M1 - e85126

ER -