1. Dr. Rico Liu Consultant, Department of Clinical Oncology, Queen Mary Hospital Honorary Clinical Associate Professor, Department of Clinical Oncology, The University of Hong Kong Deputy Hospital Chief Executive, Queen Mary Hospital BTG 2013 Feb 2013

2. Points for discussion Effects of radiation Radiotherapy is not for everyone but for whom and when The role of new technology

3. Effects of radiation External Radiotherapy High energy Xray Photon- Gama ray- from radioactive decay, e.g. Colbert High energy particles Electron Proton Brachytherapy Systemic radiotherapy apoptosis

4. Effects of therapeutic radiation

5. Normal tissue tolerance Milano et al., Semin Radiat Oncol. 17 (2007): 131-140

6. Treatment improves survival Median survival (mo) Untreated~2 WBRT alone~12 Chemotherapy follows by WBRT ~ 48 Henry JM et al. Cancer 34: 1293, 1974 Nelson DF et al. IJROBP Volume 23, Issue 1, 1992, Pages 9–17 Ferreri AJ et al. Ann Oncol. 2000 Aug;11(8):927-37

7. PCNSL: Radiotherapy alone RTOG 8315 Phase II study of WBRT 40Gy + 20Gy boost N = 41 Overall median survival 12.2 months Benefit of boost doubtful: disease recurrence frequently occurred in the boosted field, survival no better than previous study without use of boost Ocular involvement: 36Gy to both eyes (or Rx with high dose MTX) Nelson DF et al. IJROBP Volume 23, Issue 1, 1992, Pages 9–17

8. PCNSL: Chemo + radiotherapy CR 58%, PR 36% (Overall RR 94%) Overall survival 37 months 15% ( 12 patients) developed severe delayed neurologic toxicity 8 out of 12 died ( 5/8 from the group > 60 years of age and 3/8 from < 60 years of age)

10. Delayed neurotoxicity is worse for elderly patients Omuro AM et al. Arch Neurol. 2005 Oct;62(10):1595-600

12. G-PCNSL-SG-1 trial

13. Not enough evidence to forgo WBRT Limitations of the trial Low statistical power High protocol violations High rate of lost to follow up Small sample size in the analysis of neurotoxicity

14. Lower dose of RT for patients with CR

15. WBRT- set up

16. Therapeutic management of PCNSL Ferreri A J M Blood 2011;118:510-522 Role of radiotherapy

20. The role of new technology Neuro Oncol (August 2009) 11 (4): 423-429

21. Summary PCNSL is rare Chemotherapy +/- radiotherapy offer the best survival Delayed neurotoxicity is common and can cause major disability and death Reduce risk of delayed neurotoxicity lower consolidation dose for patients <60 defer WBRT for those older patients >60 Radiotherapy remains an effective treatment for patients considered not suitable for chemotherapy

22. Thank You