بسم الله الرحمن الرحيم ﴿و قل رب زدنى علماً﴾ صدق الله العظيم

Advanced Radiotherapy (RT) Dr. Ahmed Al Far, M.D. Professor of Radiation Oncology

Technical Aspects of Radiotherapy

Educational Objectives By the end of this lecture you will be able to: Describe how patients are referred for radiation oncology department. Explain the stages of health care management for patients undergoing radiotherapy. Demonstrate knowledge of the terms and concepts commonly used in radiotherapy practice.

Educational Objectives (cont.,) Identify and describe parameters of radiotherapy prescription. Discuss causes failure of radiotherapy. Explain role of quality assurance program in preventing errors. List characteristics of successful radical course of radiotherapy.

Outlines Stages leading to radiotherapy Radiotherapy process Data in radiation oncology charts Success or failure of radiotherapy

Stages Leading to Radiotherapy Staging / investigations Multidisciplinary Team Symptoms/ Screening/ Referral Diagnosis/ Primary surgery surgery or chemotherapy Radiotherapy Treatment Radiotherapy Planning

Clinical Evaluation (Path., stage,etc..) Therapy Decisions Multimodality therapy Other modality Radiotherapy Identify tumor extent and sensitive organs Decision about: (a) Goal (cure/palliation) (b) Modality (External Beam ± Brachytherapy) Position, immobilization Patient data acquisition (CT, MRI, Simulator) Flowchart for the process of RT Treatment Planning Decision about: fields, dose, beam-modifiers Treatment Simulation Radiographic verification of fields Evaluation during therapy Treatment Follow-up

Data in Radiotherapy charts-1 Patient-related: age, gender, etc. Diagnostic: clinical, pathological, TNM stage, previous treatment and concomitant medications. Pretreatment: decision making/consent Treatment technique: planning, simulation and delivery documentation Acute-radiation side effects: kind and degree at weekly basis On treatment patient education

Data in Radiotherapy charts-2 Tumor response to treatment Impact of treatment on quality of life Recommendations and compliance with follow-up Recurrence, survival (with or without disease), and date and cause of death.

Causes of radiotherapy failure-1 Indicators: Low tumor control rate, High side effects Causes: Failure to deliver the prescribed dose Failure to treat the intended volume of tissue

Causes of radiotherapy failure-2 Failure to deliver the prescribed dose: Error in dose calculation or distribution Wedge filter in wrong orientation or wrong field Beam shaping block in wrong orientation or wrong field Error in measurements of the patient's dimensions Treatment machine malfunction (output)

Causes of radiotherapy failure-3 Failure to treat the intended volume of tissue: Errors in determination target volume Errors in localization of target volume Errors in repositioning: Field displacement, Patient motion. Role of quality assurance program.

Successful Radical Course of RT Accurate localization of target volume (TV) Effective patient immobilization Uniformly high dose of radiation to the TV whilst sparing radiosensitive critical structures and normal tissues Optimum dose/fractionation schedule Accurate, consistent setting-up and execution of the treatment prescription.

Thank You