Investigations and tests

If it is suspected that a person may have cancer, doctors will carry out various tests to find out if this is the case, what type it is and how best to treat it. Below are some of those tests. Remember that these tests can also be used to investigate other conditions so having these tests doesn´t necessarily mean that the doctors think someone has cancer.

Blood Tests
Blood tests are taken by withdrawing blood from a vein via a needle and then the blood is tested in the laboratory. Blood tests are taken for all types of illnesses, not just cancer. Usually a blood test cannot determine if someone has cancer but it can give an indication of a person’s general health and how well their organs are working. Because blood tests cannot provide a complete picture of a person’s health they are used together with other tests that can give additional information.

Tumour Marker blood tests
One specific blood test is called a tumour marker blood test. Tumour markers are substances that are found in higher levels than normal in people with cancer. The substances are usually produced as a response to cancer but some of these substances are also produced by healthy cells and can therefore also be found in people who have NOT got cancer. Therefore, a blood test to detect such tumour marker substances can never be used on its own to diagnose cancer. Also, there are only a few types of cancers where researchers have found a substance that may indicate that there is a cancer present in the body.

Biopsy
A biopsy is when a small sample of tissue is taken from a person so that the cells in the tissue can be looked at under a microscope. Doctors can then check to see if there are any abnormal cells in the tissue, such as cancer cells and if so, what type of cancer it is and how severe it may be. They can take a biopsy to test for other diseases than cancer too so it doesn’t necessarily mean they suspect cancer if someone has a biopsy taken. There are different ways of removing cells to be tested depending on where the cells are. For example, you can take a ‘scraping cell biopsy’ to examine cells from the inside of the cervix and a needle biopsy to get tissue from an organ or tissue beneath the skin, e.g. from a lump in the breast.

X-ray
An x-ray machine uses high frequency energy rays (a type of radiation) that can pass through the human body and thereby produce pictures of the inside of the body. The person having an x-ray will lie on an x-ray couch or stand up against a flat surface and they have a photographic plate behind the body area that is being investigated. Once that is in position, the x-ray machine is lined up to take pictures of that particular area. Having an x-ray is painless and only takes a few minutes.

CT/CAT Scan (Computerised Axial Tomography Scan)
A CT scan takes lots of x-ray pictures from different angles and uses a computer to put them all together so that doctors can get a detailed picture of the part of the body that they want to investigate. Although the CT scanning machine takes x-rays, the machine looks a bit different from an x-ray machine because it takes pictures from different angles. The patient will lie on a couch that slides forwards and backwards through a large hole in the centre of the scanning machine as the scanner rotates around the person. The machine looks a bit like a huge doughnut. Sometimes patients are given a contrast, which is like a dye that travels through the body to help create an even clearer picture of the parts of the body that are being investigated. The contrast can be given as a drink or into a vein, depending on which body parts that are being investigated.

MRI Scan (Magnetic Resonance Imaging Scan)
The MRI scanning machine is similar to the CT scanning machine to look at, but it uses powerful magnetic fields and radio waves instead of x-rays to create a computerised image of the body parts that are being investigated. Just like the CT scan, the MRI scanner puts together pictures from many different angles so that the doctors can see cross section images of the body. In the same way as with a CT scanner, the MRI machine is a large machine with a round hole in the centre. The patient will lie on a couch that slides into the centre of the hole that is surrounded by a circular magnet. Like the CT scan, the MRI scan is painless, but the machine is very noisy and the patient has to lie completely still. Patients may also be given a contrast into a vein, which is like a dye that travels through the body via the bloodstream to help create an even clearer picture of the parts of the body that are being investigated.

Ultrasound Scan
The Ultrasound scan uses a microphone that gives off high frequency sound waves to create a picture of body parts which can be seen on a computer. To help transmit the sound waves to the microphone, the patient will have a clear gel spread onto their skin on the area that will be investigated. A microphone that is connected to a computer is then passed over the body so that the images can be seen on the computer screen. This is a painless test.

Endoscopy
With endoscopy they use a long flexible tube (called endoscope) that has a light and a tiny camera on the end. This is used to look inside the body in places where the tube can go. There are various investigations that can be done with this technique and they are named after the part of the body that is being inspected. For example a colonoscopy is when they put the tube through the anus and up into the large bowel, which is called colon. Another endoscopy could be gastroscopy when they put the tube through the mouth down via the food pipe and into the stomach. As well as examining organs with the camera they can also use the tube to take biopsies (see above) of abnormal tissues, do an internal ultrasound or remove colon polyps (growths in the colon and rectum that could develop into cancer later on).

These are some of the tests and to help you find ut more we have linked to Maggie's CancerLinks where you will be signposted to high quality information about investigations and tests.

Please get in touch with us if you have any worries or questions about cancer.

 

Page updated 6 July 2017