title: Changes in intratumor heterogeneity in blood perfusion in intradermal human melanoma xenografts during tumor growth assessed by DCE-MRI.
abstract: The purpose of this study was to use dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to search for systematic intratumor heterogeneity in blood perfusion in human melanoma xenografts growing intradermally in BALB/c-nu/nu mice. Six xenografted tumors of an amelanotic human melanoma line (A-07) were included in the study. DCE-MRI was performed daily for 5 days by using spoiled-gradient recalled sequences. Tumor images of E.F (E is initial extraction fraction and F is perfusion) were produced by subjecting DCE-MRI data to Kety analysis. E.F was used as a measure of tumor blood perfusion, since comparative studies have shown that E.F is closely related to blood perfusion in A-07 tumors. The E.F images indicated that the intratumor heterogeneity in blood perfusion was similar in all investigated tumors. The blood perfusion was low in the center of the tumors and increased toward the tumor periphery in the dorsal and ventral direction by a factor of 3-4, but not in the lateral and medial direction. The magnitude of the heterogeneity increased by a factor of approximately 2 during tumor growth. In conclusion, intradermal human melanoma xenografts show significant systematic intratumor heterogeneity in blood perfusion.
authors.affiliation: Group of Radiation Biology and Tumor Physiology, Department of Radiation Biology, Institute for Cancer Research, The Norwegian Radium Hospital, Montebello, N-0310 Oslo, Norway.
authors.forename: Bjørn A
authors.initials: BA
authors.lastname: Graff
authors.forename: Ilana C
authors.initials: IC
authors.lastname: Benjaminsen
authors.forename: Elin A
authors.initials: EA
authors.lastname: Melås
authors.forename: Kjetil G
authors.initials: KG
authors.lastname: Brurberg
authors.forename: Einar K
authors.initials: EK
authors.lastname: Rofstad
mesh_terms: D000818:Animals; D003287:Contrast Media / Q000493:pharmacokinetics; D005260:Female; D019786:Gadolinium DTPA / Q000493:pharmacokinetics; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008546:Melanoma, Experimental / Q000098:blood supply*; D051379:Mice; D008807:Mice, Inbred BALB C; D012878:Skin Neoplasms / Q000098:blood supply*; D018709:Statistics, Nonparametric; D014183:Transplantation, Heterologous
chemical_list: D003287:Contrast Media; D019786:Gadolinium DTPA