As you undergo treatment, scans will be carried out at regular intervals to keep an eye on what effect the treatment is having – these will look at your lungs, but also other parts of your body where cancer may have started growing too.
You may have already experienced some scans in the course of being diagnosed or if you have had previous treatments,1 but if they are new to you then we have summarised some basic information about them below.
CT scans take a series of X-rays which are used to build up a 3D picture of the inside of the body.2 They use a small amount of radiation, and so are unlikely to harm you or anyone who comes into contact with you after having the scan.2
Before the scan you may have a dye injected into your body, to help certain areas be seen more clearly on the scan.3
When it comes to having the scan itself, you will lie on a flat motorised bed, which will take you through the hole in the machine until you reach the part of the body that is to be scanned.3
Inside of a ring that surrounds the bed, an x-ray machine spins around and takes the x-ray images of your body.3
You’ll stay in the machine for around 10–20 minutes, and a radiographer will be on hand to support you in a nearby room. They will communicate with you through an intercom.3
After the scan, the radiographer will be able to tell you if the images the scanner has made are of a good enough quality to be used to assess your cancer, but they will not be able to give you any results.3
Unlike other scans, MRI uses magnetism and radio waves to create a detailed picture of your body.4 MRI scanners are large machines with a tube running through them – the inside of the tube is where the scan takes place.
Before the scan begins, you may need to have a special dye injected into your body to help make the scans even clearer.4
You will then lie flat on a motorised bed which will slowly move you into the machine until the part of your body that is being scanned is in the centre.4 You’ll stay in the machine for around 20–30 minutes, and a radiographer will be on hand to support and talk to you from a nearby room.4
PET scans use a small amount of mild radioactivity to help visualise the inside of the body. These scans are sometimes combined with either an MRI or a CT scan. The MRI or CT helps to visualise your body, while the PET helps to show parts of the body that are using up a lot of energy (for example, a cancer growing).6
You will need to have a special dye (sometimes called a “tracer”) injected into your body. This is a low-dose sugar solution that is mildly radioactive.6 Any areas of your body that are using the radioactive sugar solution quickly (for example, a cancer) will show up on the scan as the tracer will build up there.6 The dye needs some time to get around your body, so you may be asked to relax somewhere for a while before the scan is performed.6
When you have the scan itself, you will lie flat on a motorised bed which will slowly move you into the scanning machine until the part of your body that is being scanned is in the centre.6
You’ll stay in the machine for anywhere around 30–90 minutes, depending on what part of your body is being scanned.7 You’ll be able to talk with the radiographer while you’re in the machine, and there will be a buzzer you can press in case you feel unwell.6
After the scan, the radiographer will be able to tell you if the images the scanner has made are of a good enough quality to be used to assess your cancer, but they will not be able to give you any results.
Bone scans are used to find abnormal areas of bone in the body. It is performed similarly to a PET scan, where a radioactive tracer is injected into the body to help areas where bone is breaking down and repairing (which may happen in cancer) stand out more easily.8
You may need to wait a while between having the tracer injected into your body and having the scan.8 The scan itself will take around 30–60 minutes,8 and a radiographer will be on-hand in a nearby room. You will be able to communicate with them over an intercom system.
After the scan, the radiographer will be able to tell you if the images the scanner has made are of a good enough quality to be used to assess your cancer, but they will not be able to give you any results.
Ultrasound scanners use high frequency sound waves to visualise what is inside the body.9 There are two types of ultrasound test you may experience:
External ultrasound:9
The sonographer (the technician who administers the test) presses a special probe against your body. This emits a very high frequency sound that humans can’t hear. Inside the body, the sound waves bounce back off of your organs and other structures. These are picked up by a microphone in the probe, and converted into an image.
Endoscopic (internal) ultrasound:10
This works in much the same way as an abdominal ultrasound, however instead of a probe being pressed into the abdomen, it is inserted either down the throat or into the bottom. These are used where it may be difficult to get an image of certain parts of the body with a regular external probe. These can sometimes be uncomfortable, so your hospital may offer you an optional sedative.