1. Radiation Protection in Radiotherapy
Part No 1, Lesson No 1
Aim
IAEA Training Material on Radiation Protection in Radiotherapy
Radiation Protection in Radiotherapy
Part 1
Aim and Role of Radiotherapy
Introductory Lecture
Part 1: Aim and role of radiotherapy
Lesson 1: Introduction
Learning objectives: On completion of the module the student will be able:
To understand the principles of radiotherapy
To discuss the role of radiotherapy in cancer management
To name professionals involved in the delivery of radiotherapy
To appreciate the importance of radiation dose in radiotherapy
Activity: Lecture
Duration: 1 hour for people from non-radiotherapy background - 15min for radiotherapy professionals
Materials and equipment needed: Slide or powerpoint projector
References:
IAEA Training Material: Radiation Protection in Radiotherapy

2. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Radiotherapy
One of the main treatment modalities for cancer (often in combination with chemotherapy and surgery)
It is generally assumed that 50 to 60% of cancer patients will benefit from radiotherapy
Minor role in other diseases
Siemens Oncology
Explanation or/and additional information
Only in few countries of the world the optimum radiotherapy utilisation rate of 50 to 60% is achieved. It should be mentioned that radiotherapy is typically a very cost effective treatment modality.
While radiotherapy does not play an important role for the treatment of non-malignant diseases yet this role can be expected to increase. A particular example is endovascular brachytherapy for the prevention of restenosis.
Instructions for the lecturer/trainer
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

3. Objectives of the Module
Part No 1, Lesson No 1
Aim
Objectives of the Module
To become familiar with
the principles of radiotherapy
the role of radiotherapy in cancer management
the cost effectiveness of radiotherapy
To appreciate the importance of radiation dose in radiotherapy
Explanation or/and additional information
Cost effectiveness is always a difficult point to judge as it depends on the type of cancer treatment available and the notion of benefit if someone lives longer or just a life with better quality. Nevertheless it can be said that radiotherapy is typically cheap compared with chemotherapy.
Instructions for the lecturer/trainer
Provided the appropriate information is available, the lecturer could ask how much people think a course of radiotherapy costs in a country relevant for the course. Obviously, the costs depend very much on the facility, the complexity of the treatment and the resources required - however, about $US 3,000.- would cover a typical radiotherapy treatment in most ‘western’ countries.
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

4. Contents of the Lecture
Part No 1, Lesson No 1
Aim
Contents of the Lecture
1. Cancer management and radiotherapy
2.Approaches for dose delivery
External beam radiotherapy
Brachytherapy
3. Features of a radiotherapy department
4.Self test at the end of the lecture
”Quick test”
Explanation or/and additional information
The aim of the lecture is not to provide a deep understanding of radiotherapy but to introduce the larger picture in which radiotherapy is positioned and give a basic understanding of the discipline.
Instructions for the lecturer/trainer
Students should be made aware of the test which follows each lecture.
Point 4 should be omitted if the present lecture is part of an opening ceremony in which a test would be inappropriate.
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

5. Cancer incidence (WHO)
Part 1: Introductory lecture

6. Major indications for radiotherapy
Part No 1, Lesson No 1
Aim
Major indications for radiotherapy
Head and neck cancers
Gynaecological cancers (e.g. Cervix)
Prostate cancer
Other pelvic malignancies (rectum, bladder)
Adjuvant breast treatment
Brain cancers
Palliation
Explanation or/and additional information
Cancer incidence varies in different countries. So do treatment approaches.
Instructions for the lecturer/trainer
The list above is only of general guidance - a more specific list for the country of interest can be provided by most national cancer institutes.
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

7. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Approaches
Palliative radiotherapy to reduce pain and address acute symptoms – e.g. bone metastasis, spinal cord compression, ...
Radical radiotherapy as primary modality for cure – e.g. head and neck
Adjuvant treatment in conjunction with surgery – e.g. breast cancer
Lecture notes: Modern cancer treatment is often a combined approach with radiotherapy one part. In head and neck cancer radiotherapy is often the primary modality as it offers the prospective of cure with a larger chance of sparing organs than surgery. As a consequence radiotherapy patients are more likely to preserve voice or hearing than patients undergoing major surgery.
Instructions for the lecturer/trainer
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

8. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Aim
Patient
Critical
organs
To kill ALL viable cancer cells
To deliver as much dose as possible to the target while minimising the dose to surrounding healthy tissues
target
Beam
directions
Lecture notes: This is the central idea of radiotherapy and the lecturer should emphasis the local cancer therapy approach of radiotherapy which is particularly well suited to localised cancers. Chemotherapy, which attacks the cancer cells systemically is often complementing the localised treatment offered by surgery or radiotherapy. A consequence of this localised approach is that the spatial accuracy of the radiation delivery must be as high as possible. The accuracy of modern radiation deliver techniques can be better than a few millimeters, for example in stereotactic radiosurgery. Also conformal radiotherapy requires means of delivering radiation to a target with millimeter accuracy on many consecutive occasions (= treatment fractions).
Instructions for the lecturer/trainer
The lecturer can point out that directing a machine weighting many tons with millimeter accuracy in a living target is a major technological challenge which requires significant quality assurance and verification steps.
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

9. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Prognostic Factors
Cancer type and stage
Patient performance
Radiation dose
...
Good prognosis
survival
The figure illustrating the prognostic factors shows a survival curve for prostate cancer treatment.
Other prognostic factors could be age, gender and a variety of other factors
Bad prognosis
time
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

10. Accurate dose delivery
Part No 1, Lesson No 1
Aim
Prognostic Factors
Cancer type and stage
Patient performance
Radiation dose
...
Accurate dose delivery
matters!
This is a very important link which should be emphasized - accurate dose delivery is highly correlated to treatment outcome. This appears to be obvious but is not always as well proven as in radiotherapy.
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

11. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Dose response
100% response
means the tumour
is cured with
certainty (TCP) or
unacceptable normal
tissue damage (e.g.
paralysis) is
inevitable
The lecturer should point out that the dose scale in Gy refers to a total dose given in 2Gy fractions to the target.
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

12. Dose response Therapeutic window:
Part No 1, Lesson No 1
Aim
Dose response
Therapeutic window:
Maximum probability of Complication Free Tumour Control
The therapeutic window is typically relatively small - good technique can help to increase its size. The width of the therapeutic window and the steepness of the dose response curve determines how accurate the dose must be delivered. This theme should be mentioned here as it is continued on the next slide.
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

13. Dose should be accurate
Part No 1, Lesson No 1
Aim
Dose should be accurate
To target:
5% too low - may result in clinically detectable reduction in tumour control (e.g. Head and neck cancer: 15%)
To normal tissues:
5% too high - may lead to significant increase in normal tissue complication probability = morbidity = unacceptable side effects
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

14. “Deviations from Prescribed Dose”
Part No 1, Lesson No 1
Aim
“Deviations from Prescribed Dose”
May involve severe or even fatal consequences.
IAEA Basic Safety Standards (SS 115): ”…require prompt investigation by licensees in the event of an accidental medical exposure…”
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

15. Options for dose delivery
Part No 1, Lesson No 1
Aim
Options for dose delivery
External beam radiotherapy = dose is delivered from outside the patient using X Rays or gamma rays or high energy electrons (refer to part 5 of the course)
Brachytherapy = dose delivered from radioactive sources implanted in the patient close to the target (brachys = Greek for short distance; refer to part 6 of the course)
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

16. External beam radiotherapy
Part No 1, Lesson No 1
Aim
External beam radiotherapy
The picture shows an anthropomorphic phantom on the treatment couch of a linear accelerator. The lecturer could point out that instead of a patient an anthropomorphic phantom is shown. These phantoms are used for verification of treatment procedures. Many slides throughout the lecture will show phantoms rather than patients for confidentiality purposes - no patient should ever be identified without written informed consent.
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

17. External Beam Radiotherapy
Part No 1, Lesson No 1
Aim
External Beam Radiotherapy
Typically fractionated - e.g. 30 daily fractions of 2Gy up to a total dose of 60Gy
Superficial/orthovoltage photons (50 to 400kVp) for skin or superficial lesions
Megavoltage photons (60-Co or linear accelerators = linacs) for deeper lying tumours.
Megavoltage electrons from linacs for more superficial lesions
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

18. Superficial/orthovoltage unit
Part No 1, Lesson No 1
Aim
Superficial/orthovoltage unit
Therapax
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

19. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Modern Cobalt 60 unit
Theratronix
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

20. Linear accelerator with electron cone
Part No 1, Lesson No 1
Aim
Linear accelerator with electron cone
Varian Clinac 21C
The lecturer can point out that these units will be discussed in more detail in part 5 and 10 of the course.
Electron
applicator
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

21. Brachytherapy Interstitial implant for breast radiotherapy
Part No 1, Lesson No 1
Aim
Brachytherapy
Left a photo of an Ir implant
Right an X-ray showing the location of a gynaecological applicator
The overlays appear in a slide show!!!
Interstitial implant for breast
radiotherapy
Intracavitary
gynecological implant
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

22. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Brachytherapy
Implant of radioactive materials (e.g. 137-Cs, 192-Ir) close to the target area
Intracavitary, interstitial and mould surface applications
Low dose rate, LDR, (60Gy in about 5 days) and high dose rate, HDR, (several fractions of several Gy in few minutes each) applications
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

23. Example for HDR Brachytherapy
Part No 1, Lesson No 1
Aim
Example for HDR Brachytherapy
The picture shows a tongue implant treated using a Nucletron High Dose Rate (HDR) remote afterloading unit. The unit is equipped with a single 192-Ir source of some 10Ci activity. The source travels via the transfer tubes into the mould, one channel at a time.
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

24. A radiotherapy department is part of a health system
Part No 1, Lesson No 1
Aim
A radiotherapy department is part of a health system
Radiotherapy
Department
National
Cancer System
This slide is not necessarily applicable to all countries - it should illustrate though that radiotherapy is not a standalone unit - it is typically part of other health related structures and institutions. This needs to be taken into account when talking about finances and organizational relationships.
Oncology
Host hospital
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

25. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Patient Flow in Radio-therapy
Also within radiotherapy there is some complexity - the present slide does not include other complicating issues such as surgery or medical oncology (chemotherapy) or allied health services (social work, dieticians)
…not necessarily a straightforward process
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

26. Patient flow in radiotherapy
Part No 1, Lesson No 1
Aim
Patient flow in radiotherapy
Depends on:
disease site and stage
departmental protocols
treating clinician
resources available
The keyword ‘resources’ leads to the next slide
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

27. Components of a Radiotherapy Department
Part No 1, Lesson No 1
Aim
Components of a Radiotherapy Department
Diagnostic facilities (CT, MRI, …)
Simulator (refer to part 5 of the course)
Mouldroom
Treatment planning
External beam treatment units (parts 5 and 10)
Brachytherapy equipment (part 6)
Clinic rooms, beds, ...
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

28. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Layout of a Department
It is not essential that the participants can read every details of the plan - the plan could also be a handout. The next slide will be used to explain the context more. Things to point out:
Two linacs (on right) - should be located close to each other
Department is at least 4 times larger than the space for the treatment unit (and this does not include hospital beds)
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

29. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Layout of a Department
Physics & workshops
Simulator
Planning
Clinics
Two linac bunkers
Offices
Patient waiting
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

30. Professionals in radiotherapy
Part No 1, Lesson No 1
Aim
Professionals in radiotherapy
Radiation oncologists
Other clinicians
Medical radiation physicists
Radiation therapists
Nursing staff
Radiation safety officer
Information technology officer
Administrative staff
The lecturer can point out that other staff may also be involved - not mentioned here are porters, domestic staff, maintenance and many others - more discussion on this in part 8 occupational exposure
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

31. Features of Radiotherapy
Part No 1, Lesson No 1
Aim
Features of Radiotherapy
High and potentially lethal absorbed dose is required to cure cancer
High technology environment
Individualized treatment approach
Complex treatment set-up
This slide allows the lecturer to dwell on his or her own experience to illustrate the points. All points will also be discussed in more detail in particular in part 10 of the course- the important conclusion of this slide is shown on the next.
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

32. Features of Radiotherapy
Part No 1, Lesson No 1
Aim
Features of Radiotherapy
High and potentially lethal absorbed dose is required to cure cancer
High technology environment
Individualized treatment approach
Complex treatment set-up
Quality assurance, treatment verification and radiation protection essential
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

33. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Summary
Radiotherapy is an important cancer treatment modality
Accuracy of dose delivery is essential for good outcomes
The complex and high tech environment requires attention to quality assurance and radiation protection
Let’s summarize the main subjects we did cover in this session.
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

34. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Where to Learn More
Other parts of the course, handouts
References:
Radiotherapy physics textbooks (as per reference list)
IUCC Cancer Statistics
Radiotherapy textbooks (e.g. Perez and Brady 1998)
Site visit of a radiotherapy department (day xxx of the course)
Please edit slide to include the exact day of site visit(s)
IUCC = International Union against cancer
Perez C and Brady L (ed) Principles and practice of radiation oncology. Lippincott-Raven: Philadelphia 1998
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

35. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Any questions?
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy

36. Part 1: Introductory lecture
Part No 1, Lesson No 1
Aim
Question:
What is the main cancer treated with radiotherapy in your country and what would be a typical treatment approach? (Number of fractions? Total dose?)
This question can be used either as stand alone question which can get the participants talking about their country and background. Alternatively, it can be build into the practical exercise which follows part 1.
Typical answers are:
Prostate (western countries)
Breast
Head and Neck (Asian countries)
Part 1: Introductory lecture
IAEA Training Material: Radiation Protection in Radiotherapy