Patients will have CT scans done, in a CT Simulator, prior to treatment in order to plan there treatment so that we're in exactly the right spot and the cancer is getting the exact dose needed. For the CT scan a patient has to be comfortable and immobilisation equipment is used in order to keep them still and in the same position - this sounds like an awful term, but basically all it is is something like a head rest and something to support under their knees, for head and neck patients they will also have a shell made to keep them in the exact position.
A CT Scan and Breast immobilisation
Example of A Head and Neck shell
The plans created using the information provided from this scan can range from two different beams of radiation treating the patient.. To five or six (Intensity Modulated Radiotherapy - IMRT) creating a very precise dose distribution around the cancer target.
A Two Field Plan
An IMRT Head and Neck Plan
The patients have to be in the same position as they are for this scan when they come for treatment. To make sure this happens, the same immobilisation equipment is used, and permanent marks (aka tattoos, but no I'm afraid we can't give pretty butterflies as many patients ask!) are given to the patient during their CT. These marks then have to be aligned using lasers in the treatment room.
X-Ray images are also incooporated into the treatment machines - linac's - that we use, and are taken when the patient has been positioned on the bed correctly, another method to ensure that the patient is in the correct place. If not initially then alterations to the patients position will be made to make sure that they are.
In Tanzania however, the situation is very different - with little accuracy compared to practice over here!
The department was donated two Colbalt-60 machines (the older version of a linac, which uses a live radioactive source - and can be dangerous if this source gets stuck in an active position and will not return to the safe) and a simulator (the older version of a CT simulator, still used in some centres in the UK, but not as much as they once were). This was great.. However, the last that I heard one of these Colbalt-60 machines has broken down, along with the simulator and one of the lasers used to align patients in the working Colbalt-60 machine is broken too! So equipment wise the insitute is in a very poor state sadly.
Example of A SimulatorWith no simulator, this means no initial immobilisation (head and neck shells are reserved for the 'VIP' patients) to get patients in exact positions and no images to plan the treatment with. Therefore, there is a lack of accuracy before the treatment set up even begins! No tattoo marks are given to patients, and reference points are often just plasters stuck onto patients skin, which could easily come off - leaving the radiographers with no idea about where they are treating!
As they have nothing to plan with, basic techniques are used - those seen for palliative treatments in the UK - Single direct fields or parallel opposed paired fields, all of which are very large, leading to bad side effects; which are poorly managed.
Infection control is poor in ORCI, with there often being no running water let alone soap! As this is the case touching patients is a no go, so even if reference plasters are on the patient, they are unlikely to move the patient anyway!
The fact that the centre is working with only one Colbat-60 machine influences the throughput of patients too. As the pace in the country is slow, even in the working environment, days become very long for staff, often treating patients from 8 in the morning until 10 at night!
As you can see, the situation in Tanzania is very far from perfect and for a country with such a huge population is no-where near what is needed. I'm looking forward to going out there and experiencing all of this with my own eyes.. And seeing if there is any little thing that I could do to help!
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