2.  Multidisciplinary Effort › Surgery › Radiation › Systemic Rx (chemo, “drugs”)

3.  Assess patient  Review need for diagnostic studies  Consult with other physicians caring for the patient

4.  Goal › Deliver precisely measured dose of irradiation to a defined tumor volume with minimal damage to surrounding healthy tissue

5.  Curative › Probability of long-term survival  Palliative › Little or no hope for long-term survival › Alleviate symptoms › Improve quality of life

6.  Evaluate diagnostic studies  Knowledge of pathology  Define goal  Select appropriate treatment modalities  Determine optimal dose  Determine volumes to be treated  Monitor patient during and after treatment  Work closely with physics staff  Work closely with support staff

7.  Different doses required based on tumor type  Gross tumor volume (GTV) › All known gross disease  Clinical target volume (CTV) › GTV + regions possibly harboring microscopic disease  Planning target volume (PTV) › Margin added around CTV

8.  Simulation › “set-up” patient position and obtain CT images for planning and calculating  Treatment aids › Masks  Vac locks  Bolus  Shape Radiation Beams › MLC

9.  CT simulation  Display tumor volumes and normal tissue volumes 3-D  Dose volume histograms (DVHs)  Software advances

11.  Optimizes delivery of XRT to irregularly shaped volumes  Inverse RX planning  Dynamic delivery of XRT

12.  Begin with ideal dose distribution  Process with multiple iterations  Produces “Best Approximation” plan

14.  Dose response curves  Some general rules › Subclinical Disease = 45 - 50 Gy › Gross Disease = 65 - 80 Gy  Standard fractionation › 1.8 – 2.0 Gy per Fraction

15.  Potential for Sequela › Dose › Volume  TD 5/5  Acute side effects  Subacute side effects  Chronic side effects

16.  Optimal dose › Maximal probability tumor control with minimal frequency of complications

17.  Pre-op XRT › Eradicate subclinical disease › Decrease primary tumor volume › May affect healing from surgery  Post-op XRT › Eliminate residual tumor cells › Surgery may impair XRT effect

18.  Sequential treatment  Concurrent treatment  Goal › Increase tumor control  Disadvantage › May increase side-effects

19.  Surgery, XRT, Systemic Rx  Clinical Trials to define optimal treatment plan