BCRB 2018

19/09/2018

Tumor regression ≠ cell survival

Human s.c.c. xenograft treated with 8 X 3 Gy / 4 wks

control drug X XRT drug + XRT

Tumor removed

drug X = VEGFR2 inhibitor

Regrowth delay assay

• Comparison of growth curves of treated and untreated tumors gives the delay caused by treatment • Relationship between growth delay and surviving fraction of stem cells is complex • Regrowing cells have different environment: surrounded by dead and dying cells; vascular network is already in place

Growth Kinetics of Tumors, G.G. Steel, 1977

• Tumor bed effect