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Comparison of primary target volumes delineated on four-dimensional CT and 18 F-FDG PET/CT of non-small-cell lung cancer.

Duan YL, Li JB, Zhang YJ, Wang W, Li FX, Sun XR, Guo YL, Shang DP - Radiat Oncol (2014)

Bottom Line: The differences in the position, volume, concordance index (CI) and degree of inclusion (DI) of the targets between GTVPET and IGTV10 were compared.The best CI was between IGTV10 and GTVPET15% (0.57).The best DI of IGTV10 in GTVPET was IGTV10 in GTVPET15% (0.80).

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Jinan 250117, China. lijianbin@msn.com.

ABSTRACT

Background: To determine the optimal threshold of 18 F-fluorodexyglucose (18 F-FDG) positron emission tomography CT (PET/CT) images that generates the best volumetric match to internal gross target volume (IGTV) based on four-dimensional CT (4DCT) images.

Methods: Twenty patients with non-small cell lung cancer (NSCLC) underwent enhanced three-dimensional CT (3DCT) scan followed by enhanced 4DCT scan of the thorax under normal free breathing with the administration of intravenous contrast agents. A total of 100 ml of ioversol was injected intravenously, 2 ml/s for 3DCT and 1 ml/s for 4DCT. Then 18 F-FDG PET/CT scan was performed based on the same positioning parameters (the same immobilization devices and identical position verified by laser localizer as well as skin marks). Gross target volumes (GTVs) of the primary tumor were contoured on the ten phases images of 4DCT to generate IGTV10. GTVPET were determined with eight different threshold using an auto-contouring function. The differences in the position, volume, concordance index (CI) and degree of inclusion (DI) of the targets between GTVPET and IGTV10 were compared.

Results: The images from seventeen patients were suitable for further analysis. Significant differences between the centric coordinate positions of GTVPET (excluding GTVPET15%) and IGTV10 were observed only in z axes (P < 0.05). GTVPET15%, GTVPET25% and GTVPET2.0 were not statistically different from IGTV10 (P < 0.05). GTVPET15% approximated closely to IGTV10 with median percentage volume changes of 4.86%. The best CI was between IGTV10 and GTVPET15% (0.57). The best DI of IGTV10 in GTVPET was IGTV10 in GTVPET15% (0.80).

Conclusion: None of the PET-based contours had both close spatial and volumetric approximation to the 4DCT IGTV10. At present 3D-PET/CT should not be used for IGTV generation.

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Related in: MedlinePlus

Median percentage volume change of GTVPETto IGTV10. SUV n = SUV of n; SUV n% = n% of maximum SUV.
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Fig1: Median percentage volume change of GTVPETto IGTV10. SUV n = SUV of n; SUV n% = n% of maximum SUV.

Mentions: The volumes of primary tumors measured by PET/CT and 4DCT were shown in Table 3. Compared to IGTV10, GTVPET15%, GTVPET20% and GTVPET2.0 showed no significant difference (P values were 0.281, 0.102 and 0.687, respectively). Figure 1 illustrated the median percentage of volume changes from GTVPET to IGTV10 standardized to the IGTV10 for each case. The SUV 15% contour approximated most closely to the IGTV10 with the lowest median percentage volume changes of 4.86%. The corresponding values with respect to the IGTV10 for the SUV20%, SUV25%, SUV30%, SUV35%, SUV40%, SUV2.0 and SUV2.5 contours were −8.87%, −24.51%, −37.51%, −43.57%, −52.24%, −7.03% and −21.93%, respectively.Table 3


Comparison of primary target volumes delineated on four-dimensional CT and 18 F-FDG PET/CT of non-small-cell lung cancer.

Duan YL, Li JB, Zhang YJ, Wang W, Li FX, Sun XR, Guo YL, Shang DP - Radiat Oncol (2014)

Median percentage volume change of GTVPETto IGTV10. SUV n = SUV of n; SUV n% = n% of maximum SUV.
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4150978&req=5

Fig1: Median percentage volume change of GTVPETto IGTV10. SUV n = SUV of n; SUV n% = n% of maximum SUV.
Mentions: The volumes of primary tumors measured by PET/CT and 4DCT were shown in Table 3. Compared to IGTV10, GTVPET15%, GTVPET20% and GTVPET2.0 showed no significant difference (P values were 0.281, 0.102 and 0.687, respectively). Figure 1 illustrated the median percentage of volume changes from GTVPET to IGTV10 standardized to the IGTV10 for each case. The SUV 15% contour approximated most closely to the IGTV10 with the lowest median percentage volume changes of 4.86%. The corresponding values with respect to the IGTV10 for the SUV20%, SUV25%, SUV30%, SUV35%, SUV40%, SUV2.0 and SUV2.5 contours were −8.87%, −24.51%, −37.51%, −43.57%, −52.24%, −7.03% and −21.93%, respectively.Table 3

Bottom Line: The differences in the position, volume, concordance index (CI) and degree of inclusion (DI) of the targets between GTVPET and IGTV10 were compared.The best CI was between IGTV10 and GTVPET15% (0.57).The best DI of IGTV10 in GTVPET was IGTV10 in GTVPET15% (0.80).

View Article: PubMed Central - PubMed

Affiliation: Department of Radiation Oncology, Shandong Cancer Hospital and Institute, Jinan 250117, China. lijianbin@msn.com.

ABSTRACT

Background: To determine the optimal threshold of 18 F-fluorodexyglucose (18 F-FDG) positron emission tomography CT (PET/CT) images that generates the best volumetric match to internal gross target volume (IGTV) based on four-dimensional CT (4DCT) images.

Methods: Twenty patients with non-small cell lung cancer (NSCLC) underwent enhanced three-dimensional CT (3DCT) scan followed by enhanced 4DCT scan of the thorax under normal free breathing with the administration of intravenous contrast agents. A total of 100 ml of ioversol was injected intravenously, 2 ml/s for 3DCT and 1 ml/s for 4DCT. Then 18 F-FDG PET/CT scan was performed based on the same positioning parameters (the same immobilization devices and identical position verified by laser localizer as well as skin marks). Gross target volumes (GTVs) of the primary tumor were contoured on the ten phases images of 4DCT to generate IGTV10. GTVPET were determined with eight different threshold using an auto-contouring function. The differences in the position, volume, concordance index (CI) and degree of inclusion (DI) of the targets between GTVPET and IGTV10 were compared.

Results: The images from seventeen patients were suitable for further analysis. Significant differences between the centric coordinate positions of GTVPET (excluding GTVPET15%) and IGTV10 were observed only in z axes (P < 0.05). GTVPET15%, GTVPET25% and GTVPET2.0 were not statistically different from IGTV10 (P < 0.05). GTVPET15% approximated closely to IGTV10 with median percentage volume changes of 4.86%. The best CI was between IGTV10 and GTVPET15% (0.57). The best DI of IGTV10 in GTVPET was IGTV10 in GTVPET15% (0.80).

Conclusion: None of the PET-based contours had both close spatial and volumetric approximation to the 4DCT IGTV10. At present 3D-PET/CT should not be used for IGTV generation.

Show MeSH
Related in: MedlinePlus