Detection of lymph node involvement in hematologic malignancies using micromagnetic resonance lymphangiography with a gadolinum-labeled dendrimer nanoparticle.
Animal models of lymphoma should reflect their counterparts in humans; however, it can be difficult to ascertain whether an induced disease is intralymphatic or extralymphatic based on direct visualization. Current imaging methods are insufficient for identifying lymphatic and intralymphatic involvement. To differentiate intralymphatic from extralymphatic involvement, we have developed a magnetic resonance imaging-based lymphangiography method and tested it on two animal models of lymphoma. A gadolinium (Gd)-labeled dendrimer nanoparticle (generation-6; approximately 220 kDa/ approximately 10 nm) was injected interstitially into mice bearing hematologic malignancies to perform dynamic micromagnetic resonance lymphangiography (micro-MRL). Both a standard T1-weighted 3D fast spoiled gradient echo and a T2/T1-weighted 3D fast imaging employing steady-state acquisition (3D-FIESTA-C) were compared in an imaging study to differentiate intralymphatic from extralymphatic involvement of tumors. The lymphatics and lymph nodes were visualized with both methods in all cases. In addition, 3D-FIESTA-C depicted both the lymphatic system and the extralymphatic tumor. In an animal model, 3D-FIESTA-C demonstrated that the bulk of the tumor thought to be intralymphatic was actually extralymphatic. In conclusion, micro-MRL, using Gd-labeled dendrimer nanoparticles with the combined method, can define both the normal and abnormal lymphatics and can distinguish intralymphatic from extralymphatic diseases in mouse models of malignant lymphoma.
Kobayashi
Hisataka
H
Molecular Imaging Program, Center for Cancer Research, National Cancer Institute, National Institutes of Health, Bethesda, MD 20892-1088, USA. kobayashi@mail.nih.gov
Kawamoto
Satomi
S
Brechbiel
Martin W
MW
Bernardo
Marcelino
M
Sato
Noriko
N
Waldmann
Thomas A
TA
Tagaya
Yutaka
Y
Choyke
Peter L
PL
D000818:Animals; D045744:Cell Line, Tumor; D004195:Disease Models, Animal; D005260:Female; D005682:Gadolinium; D019337:Hematologic Neoplasms / Q000473:pathology*; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008279:Magnetic Resonance Imaging; D015674:Mammary Neoplasms, Animal / Q000473:pathology; D051379:Mice; D008819:Mice, Nude; D049329:Nanostructures
D005682:Gadolinium