1. Hemoglobin level significantly impacts the tumour cell survival fraction in humans after internal radiotherapy: application of a preclinical radiobiology model to clinical data. Stephan Walrand, Renaud Lhommel, Pierre Goffette, Marc Van den Eynde, Stanislas Pauwels, François Jamar Cliniques Universitaires Saint Luc, Université Catholique de Louvain, Avenue Hippocrate 10, 1200 Brussels, Belgium stephan.walrand@uclouvain.be

2. OER R 2 = 0.53 10 11 13 13.4 14.3 14.8 HEF x D tumor cells survival fraction Hb (Gy) Hb Enhancement Factor UCL Brussels HEF = 1 + k (Hb – 13) HEF Hb 1 k>0 HEF Hb 1 k=0 k = 0.00 Dose-effect relationship labeled with patient Hb level let see in the following animation what will happen if we increase k

3. - R 2 = 0.53 tumor cells survival fraction (Gy) UCL Brussels k = 0.01 HEF x D

4. R 2 = 0.56 tumor cells survival fraction (Gy) UCL Brussels k = 0.02 HEF x D

5. R 2 = 0.60 tumor cells survival fraction (Gy) UCL Brussels k = 0.03 HEF x D

6. R 2 = 0.63 tumor cells survival fraction (Gy) UCL Brussels k = 0.04 HEF x D

7. R 2 = 0.66 tumor cells survival fraction (Gy) UCL Brussels k = 0.05 HEF x D

8. R 2 = 0.69 tumor cells survival fraction (Gy) UCL Brussels k = 0.06 HEF x D

9. R 2 = 0.72 tumor cells survival fraction (Gy) UCL Brussels k = 0.07 HEF x D

10. R 2 = 0.75 tumor cells survival fraction (Gy) UCL Brussels k = 0.08 HEF x D

11. R 2 = 0.78 tumor cells survival fraction (Gy) UCL Brussels k = 0.09 HEF x D

12. R 2 = 0.80 tumor cells survival fraction (Gy) UCL Brussels k = 0.10 HEF x D

13. R 2 = 0.83 tumor cells survival fraction (Gy) UCL Brussels k = 0.11 HEF x D

14. R 2 = 0.85 tumor cells survival fraction (Gy) UCL Brussels k = 0.12 HEF x D

15. R 2 = 0.87 tumor cells survival fraction (Gy) UCL Brussels k = 0.13 HEF x D

16. R 2 = 0.89 tumor cells survival fraction (Gy) UCL Brussels k = 0.14 HEF x D

17. R 2 = 0.90 tumor cells survival fraction (Gy) UCL Brussels k = 0.15 HEF x D

18. R 2 = 0.91 tumor cells survival fraction (Gy) UCL Brussels k = 0.16 HEF x D

19. R 2 = 0.92 tumor cells survival fraction (Gy) UCL Brussels k = 0.17 HEF x D

20. R 2 = 0.93 tumor cells survival fraction (Gy) UCL Brussels k = 0.18 HEF x D

21. R 2 = 0.93 tumor cells survival fraction (Gy) UCL Brussels k = 0.19 HEF x D

22. R 2 = 0.93 tumor cells survival fraction (Gy) UCL Brussels k = 0.21 HEF x D

23. R 2 = 0.93 tumor cells survival fraction (Gy) UCL Brussels k = 0.23 R 2 optimum optimal HEF per patient HEF x D