These tests are used to assess the heart for any adverse effects of treatment or complications. 

• Echocardiogram ('Echo'} 

An echocardiogram (ultrasound of the heart) measures the motion of the walls of the heart and the heart valves by using sound waves. A gel is applied to the chest and a gentle probe is moved back and forth over the skin covering the area of the heart. There is no discomfort or side effects associated with this test. 

• Electrocardiogram (ECG} 

An electrocardiogram (ECG) records the electrical activity of the heart. During an ECG, the child lies quietly while rubber pads called electrodes, which are attached by wires to the machine, are placed on the wrists, legs and chest. Recordings are made on a strip of paper. There are no side effects. 

Hearing tests are done to determine if there is any high frequency hearing loss as a result of treatment with certain antibiotics or chemotherapeutic agents. 

An audiogram measures hearing. Your child may be asked to wear headphones or have their hearing tested in a soundproof booth. 

Very young children may need to have their hearing tested while asleep. This type of hearing test is done by measurement of brain waves when exposed to different sounds. 

There are no side effects or pain associated with an audiogram. 

•  Glomerular filtration rate (GFR} 

In a GFR test, a special dye is injected , after which blood samples are taken to measure how much dye remains in the blood. The GFR shows how well the kidneys are working by measuring how quickly the dye is removed from the blood. 

• Urine testing (urinalysis} 

A urinalysis tests the urine. A small amount of urine is collected in a jar. This is done regularly to test kidney function and to see if there is any infection in the urinary tract. Your child may be asked to provide a urine sample if an infection is suspected. A clean sample of urine may also be sent to a lab if further information is required. 

The liver performs many vital functions in the body, including the breakdown and excretion of drugs and harmful chemicals. Liver function tests (LFTs) involve analysing the blood to find out how well the liver is doing its job. 

Pulmonary functions tests (PFTs) measure how well the lungs are working. The test measures how much air the lungs can hold and how well your child can push air out of the lungs. 

It looks at whether disease, medication or infection has affected the way in which the lungs work. It is only performed on children who are five years or older, as a certain level of ability is needed to use the equipment. 

• your child will be asked to blow into a plastic mouthpiece connected to a machine
• the machine measures the amount of air breathed in and the force of air breathed out
• the test may be repeated a few times to get an accurate reading. 

Nuclear medicine studies are often done to look for small bits of tumour that might not show up using other methods. Nuclear medicine studies can detect metastatic disease (distant spread of the cancer) and can also provide information on:

• the growth of a tumour
•  the response of the disease to treatment
• how well different body organs are functioning. 

How it works:

• a tiny amount of radioactive compound called a radiotracer is injected 
• the radioactivity is detected by a special gamma camera 
• a computer then forms the images showing how the radiotracer is distributed in the body. 

The amount of radioactivity used for nuclear studies is so small it carries no risk to the child. The radiotracer only stays in the body temporarily and is eliminated when the child later goes to the toilet.

During imaging, the child must lie very still so that the images do not blur. Sometimes sedation is required, particularly for young children.