Tumour-infiltrating CD11b+ myelomonocytes and response to fractionated irradiation of human squamous cell carcinoma (hSCC) xenografts.

Purpose: Bone marrow derived CD11b+ myelomonocytes have been shown to be recruited by the tumour and to promote tumour regrowth after irradiation. Here we investigated in a panel of well characterised hSCC tumour models the number of tumour-infiltrating CD11b+ cells and the association with response to clinically relevant fractionated irradiation.

Methods: Six hSCC tumour models (UT-SCC-5, -14, -15, XF354, FaDu, SAS) xenografted in nude mice were excised after injection of pimonidazole hypoxia marker before irradiation and after 5 and 10 fractions.

Comparison of [18F]FDG uptake and distribution with hypoxia and proliferation in FaDu human squamous cell carcinoma (hSCC) xenografts after single dose irradiation.

Purpose: This study investigated the uptake of [(18)F]2-fluoro-2-deoxy-glucose ([(18)F]FDG) in the human tumour xenograft FaDu at early time points after single dose irradiation with Positron-Emission-Tomography (PET), autoradiography and functional histology.

Materials And Methods: [(18)F]FDG-PET of FaDu hSCC xenografts on nude mice was performed before 25 Gy or 35 Gy single dose irradiation and one, seven or 11 days post irradiation (p.irr.