Fighting Cancer in Africa - Voices of doctors and patients (IAEA) April 2006
Planning treatment with radiation therapy
Kavuma Awosi: Medical Physicist
Summary:
Once cancer is diagnosed and deemed treatable, it is the job of a medical physicist to plan the patient's radiation treatment. In the case of breast cancer, the objective is to maximise radiation to the tumour in the breast, but minimise radiation to surrounding areas, such as the lung. Kavuma Awosi, medical physicist at Mulago Hospital uses machines to measure the tumours from every angle so he can pinpoint where radiation should be targeted and calculate how much radiation should be allowed to hit the body and for how long.
Suggested introduction:
Cancers can grow in any part of the body. If it is treatable, then wherever the cancer grows, even if it is deep inside the body, it needs to be measured from every angle. It is the job of the medical physicist to use machines to take all those measurements and then calculate how much radiation should be allowed to hit the body, where and for how long.
Kavumoi Awosi has been Mulago Hospital's medical physicist since the unit was set up with the support of IAEA ten years ago. It is a responsibility he takes very seriously and a job that he loves. He explains to Susie Emmett how he calculates the radiation therapy required.
Tape in:
There are several tools that...
Tape out:
...gives a lot of satisfaction.
Closing Announcement:
A media toolkit for reporting on cancer and its treatment. This pack has been produced for the International Atomic Energy Agency (IAEA).
Transcript
Awosi
There are several tools that are used in the planning. We have the radiotherapy simulator; this is the machine that is used to see how deep or how wide the tumour is, that is one of the big tools that we must have.
Emmett
So in other words a patient like those patients that are waiting outside in the waiting room, they may go and be assessed by this machine, so you need to know exactly the size, the shape and the position of the cancer, of the tumour?
Emmett
And then what do you do next?
Awosi
Then all that information is documented and the information is fed into a treatment planning computer from which the treatment time for every patient can be calculated.
Emmett
Now I think that treatment planning computer is right in front of us here. Can you demonstrate how you do this? It is a very large screen for a start.
Awosi
Ok for example I have a typical case of breast. What you can see on the screen are the different slices of the breasts.
Emmett
So this is almost like a photograph inside the woman's body?
Awosi
Yes, yes. Showing the area of the tumour, showing the lung.
Emmett
Behind the breast, behind the tumour?
Awosi
Just behind the breast, it is one of the critical organs because when we are treating the breast we want to treat only the breast and one of the main objectives of radiotherapy planning is to maximize radiation to the affected area and minimize radiation to the normal. And when we are planning breast, the lungs is one of the normal organs which we have to make sure that it gets almost negligible radiation dosage.
Emmett
So you do not want to hit the lung because that is needed for healthy living?
Emmett
So here you are, you have got the tumour, there is the lung behind it. What are all these coloured lines? There is a red line, green line, blue line?
Awosi
These coloured lines indicate the radiation levels at that particular point. For example the red line here means that the dosage is 100%.
Emmett
So now you can adjust where the radiation comes from in order to hit that tumour, to hit the cancer?
Awosi
Yes, we can adjust the angle, how are we going to angulate our machine such that we get maximum radiation to the affected area and minimum radiation to the lung just in case of the breast treatment.
Emmett
So how long does it take for you to work out a treatment plan?
Awosi
Well treatment plans vary from patient to patient and from complexity. Some treatment plans are more easier than others but all in all it may take about two to three hours to complete a plan.
Emmett
Now I can see that what you are doing is very precise, very scientific, does that mean that you never really get to have close contact with the patients, with the 'people' side of treating cancer? Are you like the scientist behind the treatment?
Awosi
Well quite often we have to interact because really radiotherapy is a team work. Quite often the doctors or the radiotherapists have to consult me, how are we going to plan this and also the radiographers, the people who do the treatment themselves have to come to me. So quite often we interact in the process of radiotherapy. It is a team work. If you see somebody who came in with a lot of pain, if you treat and see that after sometime he feels a little better, that gives a lot of satisfaction. End of track
