Understanding The Most Common Childhood Cancers: A Comprehensive Guide For Parents

As compared to the global adult population, children are affected by several different types of childhood cancer. Did you know that:

• About half of childhood cancers are related to blood cells (leukaemia and lymphoma). 
• There are two types of frequent malignant childhood cancer: those of the central nervous system and those that develop from embryonal tissues.
• Some cancers are exclusive to children. These may include neuroblastoma (begins in the adrenal glands) and retinoblastoma (stems from the immature cells of the retina). It may also include nephroblastoma (begins in the kidney).
• Tumours or cancers of the breast, lung, or stomach are usually rare in children.
• Although there have been major advancements in technology, the American Cancer Society (ACS) reveals that top childhood cancers still remain the second cause of death among young children.

Types Of Childhood Cancer: The Top 5

Types of childhood cancer can be difficult to identify. That’s because fevers, bruises and even common illnesses can often mask the early symptoms. So let’s understand each of these types of childhood cancer, and the warning signs for each. 

1. Acute Lymphoblastic Leukemia (ALL)

Leukaemia is the cancer of white blood cells (WBC). It occurs when the bone marrow produces an abnormal number of immature white blood cells. These immature WBCs then travel through the bloodstream and overcrowd healthy cells, thereby increasing the chances of infection in the body. 

This types of childhood cancer commonly occur in kids and teenagers and could either be chronic or acute. It is one of the top childhood cancers, globally. As per data from the American Cancer Society, leukaemia accounts for 30 per cent of all types of cancers in children. 

As mentioned in our article on childhood leukaemia, while the former takes time before it becomes fatal, the latter is a fast-growing cancer. 

Types 

• Acute lymphocytic leukaemia: Here, the bone marrow creates an unhealthy number of lymphocytes (a type of white blood cells).
• Acute myelogenous leukaemia: In this type, cancer starts from the bone marrow where a large number of immature WBCs are produced.
• Hybrid or mixed-lineage leukaemia: This is a combination of the above two types of leukaemia cancers. 
• Chronic myelogenous leukaemia: While this type of cancer is rare in kids, it is caused by chromosome mutation. 
• Chronic lymphocytic leukaemia: This type of cancer is extremely rare in kids and mostly occurs in older adults. 
• Juvenile myelomonocytic leukaemia: This rare type of cancer is neither chronic or acute and affects kids under the age of four. 

Symptoms 

• Re-occurring infections
• Frequent bruising and bleeding 
• Poor appetite and stomachache 
• Breathing troubles
• Swelling in the body 
• Joint and bone pain
• Acute anaemia 

Diagnosis  

In order to diagnose leukaemia, the healthcare provider may access your child’s condition based on either a physical examination, blood test and a bone marrow test.

Treatment 

• Chemotherapy: This type of treatment involves the use of a drug or a combination of drugs to treat leukaemia, which might be given orally through a pill or an injection. 
• Targeted treatment: In this type of leukaemia treatment, the immature WBCs are targeted for their specific vulnerabilities. This is identified on the basis of the Leukemia symptoms in kids.
• Radiation therapy: As the name suggests, different types of radiation, including x-ray or even high-energy beams, are used to target and kill growing leukaemia cells. 
• Biological treatment: This treatment helps the immune system to recognise the growth of leukaemia cells in the body and target to destroy them. 
• Stem cell transplant: This is also a common procedure to cure cancer. Here, deceased bone marrow is replaced with one that is healthy.  

Remember, childhood leukaemia is curable in most cases. So begin by informing yourself about the condition, speak to your doctor about the symptoms and chart out the treatment plan if it is diagnosed.

2. Brain tumour 

When there is abnormal cell growth in the brain, it becomes a tumour. This can either be benign (not cancer) or malignant (cancer) and is one of the top childhood cancers. 

According to the ACS, “Brain and central nervous system tumours are the second most common cancers in children, making up about 26 per cent of childhood cancers.” 

The agency also adds that most brain tumours found in children typically start in the lower parts of the brain including the cerebellum or the brain stem.

Types 

The American Society of Clinical Oncology lists the various tumours that lead to cancer of the brain or the spinal cord. 

• Glial tumours. These are various tumours that develop in the central nervous system from the glial cells. These include Astrocytoma, Oligodendroglioma, Ependymoma, Choroid plexus carcinoma, Oligoastrocytoma, and Glioblastoma. 
• Mixed glial neuronal tumours. They are a rare type of tumour that also occur in the central nervous system. These tumours include Ganglioglioma, Desmoplastic infantile ganglioglioma, Pleomorphioc xanthoastrocytoma, and Anaplastic ganglioglioma.
• Neural tumours. Another type of brain tumour or that of the central nervous system is the neural or neuronal tumour. These include Gangliocytoma and Neurocytoma.
• Embryonal tumours. These are tumours that are formed from the embryonic cells that remain in a child’s brain after birth. As per the National Cancer Institute, U.S, they spread through the cerebrospinal fluid and include Medulloblastoma and Medulloepithelioma tumours. 
• Ependymoblastoma. This is a highly malignant brain tumour of childhood and is usually seen in babies and toddlers or very young children. It includes Atypical Teratoid/Rhabdoid tumours.
• Pineal tumours. These type of tumours occur in the pineal gland and reportedly account for three per cent to eight per cent of the intracranial tumours in kids. The tumours that develop in this type of cancer are called Pineocytoma. 

Symptoms 

• Constant headaches
• Feeling of dizziness
• Imbalance in the body
• Vision, hearing or speech impairment 
• Frequent vomiting
• Lack of concentration 
• Memory loss
• Numbness and weakness

Diagnosis of brain tumour

• Physical examination. The healthcare provider may inspect your child to check if he has a bulging fontanelle (soft spot on your baby’s head), enlarged eyes, and red reflex in the eye (it shouldn’t be there). Plus, a positive Babinski reflex (occurs after the sole of the baby’s foot is stroked) and separated sutures are checked. 
• Computed Tomography (CT) scan. The computed tomography (CT) scan uses x-ray and creates images of the brain and skull. The three-dimensional models created with this scan can reveal the presence of a tumour. It usually takes about a few seconds to a few minutes.
• Magnetic resonance imaging (MRI). The MRI scan machine uses magnets as well as radio waves to create images of the brain and its surrounding tissues. This helps to locate the brain tumour. The test may last from 30 to 60 minutes. 
• Examination of the cerebrospinal fluid. Usually, the doctors will do a lumbar puncture to collect the cerebrospinal fluid from the spinal cord. It can reveal data about proteins as well as the sugar content in the body.   

Most of these tests are usually done based on the child’s age, tumour size, tumour type and location in the central nervous system.

Treatment 

• Surgery. Surgery may be done to remove Astrocytoma (glial cell tumour) with the addition of chemotherapy and radiation therapy. Similarly, for Ependymomas (originates from the ependyma tissue of the central nervous system) surgery is needed along with the two therapies. 
• Radiation and chemotherapy. Only surgery cannot remove Medulloblastomas tumour and therefore, one needs these therapies. Similarly, for Brainstem gliomas (cancerous) surgery is not possible because it is usually located deep inside the brain. So radiation is required to reduce the size of the tumour.

3. Neuroblastoma

Among the type of childhood cancer, this one usually develops due to immature nerve cells. Typically, it begins from the adrenal glands that are located on top of the kidneys. It then slowly develops into malignant tumours that may appear in the abdomen, chest, or even in nerve tissues of the spinal cord. 

According to the National Cancer Institute, Neuroblastoma often affects children below the age of five. And while it is believed to begin before birth, it can only be detected after the child begins to show symptoms. Usually, due to its slow growth, doctors are able to diagnose it early. 

Types 

The American Cancer Society lists the two types of neuroblastomas as follows: 

• Ganglioneuroma: This is a benign (non-cancerous) type of tumour. It is made up of nerve sheath cells as well as mature ganglion.
• Ganglioneuroblastoma: This type of tumour has both benign and malignant parts. It has neuroblasts (immature nerve cells) that grow and spread across the autonomic nervous system abnormally. Doctors usually have to study these types of tumours carefully to make sure that there are no malignant cells. 

Symptoms 

• Presence of a lump in abdomen, chest, neck and/or pelvis
• Impaired ability to walk
• Blue or purple nodules under the skin
• Bulging eyes with dark circles as well as droopy eyelids
• Body ache, typically in the chest, arms and legs
• Diarrhoea
• High blood pressure
• Fever and anaemia 

Sometimes, kids with neuroblastoma don’t exhibit any of these symptoms. They may have another illness that is the underlying symptom of this type of cancer. If you are concerned about any of these changes, you must consult a doctor. 

Diagnosis of Neuroblastoma

The following diagnostic tests are recommended by the American Society of Clinical Oncology: 

• Blood tests: Here, doctors will take complete blood counts (CBC) to find out if the child has anaemia (low levels of red blood cells). They can also evaluate liver and kidney function with blood tests. They may also check for blood clots.
• Urine tests: A urine sample is collected to identify tumour markers that a neuroblastoma tumour produces. If your child has this type of cancer, the tumour marker found in the urine will be much higher than normal. 
• Biopsy: In a biopsy, the doctors may remove a small part of the tissue from the tumour for examination. A pathologist who will analyse this piece under a microscope can then evaluate the tumour. 
• Genetic studies: In some cases, neuroblastoma cell DNA is used to detect changes in the oncogene MYCN. If it is more than 10 copies of the gene, it can be a tumour growth.
• Bone marrow aspiration: This method examines the bone marrow. Doctors may take a small tissue sample and its fluid from the pelvic area. 
• Other tests: Some other tests to identify this type of cancer is a CT scan, an MRI scan as well as a meta-iodobenzylguanidine (MIBG) scan. The last scan studies the protein that neuroblastoma cells absorb. Additionally, some patients may also need a positron emission tomography (PET) or PET-CT scan. This type of scan creates images of organs and tissues. 

Not all children suffering from neuroblastoma cancer need all these tests. Their use depends on the spread of the tumour and its location and is completely up to the predisposition of the doctor. 

Treatment 

Once the diagnosis is complete, a child may need the following treatments:

• Surgery to remove the tumour
• Chemotherapy, in which doctors will give anti-cancer drugs intravenously 
• Radiation therapy, in which doctors use powerful rays to remove the tumour 
• High-dose chemotherapy or radiation therapy and even stem cell transplant in some cases 
• Retinoid therapy, in which the patient is administered with chemicals that are related to vitamin A
• Immunotherapy, wherein medication is given so that the patient’s immune system is able to fight off cancer cells

4. Wilms Tumor or Nephroblastoma

Another one of the common types of childhood cancer, nephroblastoma accounts for about five per cent of all paediatric cancers. In this type of cancer, immature cells begin to develop in the kidneys of an infant.

Ideally, the kidneys should mature by the time the child turns three or four. But when they don’t, they stick together to form a mass of immature cells (Wilms tumour). And, it is also one of the top types of childhood cancer. 

Unfortunately, this tumour is always cancerous. 

Types 

As per ASCO, there are two types of tumours based on their development in the kidneys:

• Unilateral Wilms tumour: When the tumour develops only in one kidney, it is unilateral. This means the mass of immature cells only affects one of the kidneys.
• Bilateral Wilms tumour: Here, the immature cells spread across both the kidneys. Usually, when a child suffers from bilateral Wilms tumour, the immature cells develop in both kidneys simultaneously. Very rarely do doctors find one kidney affected after the other. This makes it quite a deadly childhood cancer.  

In addition, Wilms tumour can be of two types based on their appearance. As per the American Cancer Society, the following are the two types:

• Favourable histology: The apex agency notes, “Although the cancer cells in these tumours don’t look quite normal, there is no anaplasia (see next paragraph). More than 9 of 10 Wilms tumours have a favourable histology. The chance of curing children with these tumours is very good.”
• Unfavourable histology (anaplastic Wilms tumour): In these types of tumours, the look of the cancer cells varies. Here, the cells’ nuclei (the central parts that hold a person’s DNA) become large and sometimes distorted. The agency notes, “This is called anaplasia. The more anaplasia a tumour has, the harder it is to cure.”

Symptoms 

• Swelling or lump in and around the belly
• Constant fever
• Pain around the abdomen or in the body in general
• Feeling of nausea
• Very poor appetite

Diagnosis 

The American Cancer Society lists the following diagnostic tests for nephroblastoma:

• Physical examination: Along with your child’s medical history, the doctor will also conduct a physical examination. They may question your child about the symptoms and even birth defects and family history related to genitals and the urinary system. During the physical examination, the doctor will check your child’s abdomen and may even collect blood and urine samples. 
• Imaging tests: If your doctor suspects a nephroblastoma, he might recommend imaging tests. In these tests, doctors use sound waves, x-rays, magnetic fields, and radioactive substances to create images of the body’s organs.
• Ultrasound (sonogram): An ultrasound will reveal Wilms tumour or any other type of abdominal tumour. This test is easy and gives the doctor a proper view of the kidneys.
• Other tests: Some other tests such as the computed tomography CT scan, the MRI scan, chest x-rays as well as bone scans can show the tumours if present.
• Kidney biopsy: Although, most of the time an imaging test can reveal the tumour, sometimes it may take a biopsy to understand it.  

Treatment 

The three primary treatments for these types of childhood cancer are chemotherapy, surgery, and radiation therapy. Remember, in most cases this is curable. However, you may need to seek immediate medical attention to bring it under control and treat it in time. 

Although most children get more than one treatment, there are alternative therapies that some doctors might recommend. As per the ACS, these include “vitamins, herbs, and special diets, or other methods such as acupuncture or massage.” 

5. Lymphoma 

The final one in the list of types of childhood cancer is Lymphoma. It begins in certain cells of the child’s immune system.

As per the Roswell Park Comprehensive Cancer Centre, “These cancers affect lymph nodes and lymph tissues, like the tonsils or thymus. They can also affect the bone marrow and other organs, and can cause different symptoms depending on where the cancer is growing.” 

Types 

• Hodgkin’s lymphoma: This type of lymphoma begins in the white blood cells (lymphocytes). Since the lymph tissue are present in many parts of the body, this type of cancer can start from anywhere. These parts could be the lymph nodes, spleen, bone marrow, thymus, digestive tract and adenoids and tonsils.  
  Hodgkin’s lymphoma further has four types. But it is Nodular sclerosis Hodgkin lymphoma that actually affects the kids. According to the ACS, this usually starts from the lymph nodes in the neck or the chest area.
• Non-Hodgkin lymphoma: This type of cancer is more likely to occur in young children, than the former. The cancerous cells in this type of cancer grow quickly and intensively. Therefore, they may also need aggressive treatment to control. 

Both types have similar symptoms and so only a proper diagnosis can detect them.

Symptoms 

The signs that are indicative of lymphoma include the following:

• Swollen lymph nodes, especially in the neck, armpit, or groin areas
• Rapid weight loss
• Constant fever
• Hot flashes or sweat
• Feeling or weakness

Diagnosis 

A blood test cannot detect lymphoma. To diagnose this type of childhood cancer, your doctor might recommend the following tests: 

• Physical examination: On the basis of the symptoms, the doctor will examine your child’s enlarged lymph nodes or spleen. He may even ask questions about his medical history.
• Biopsy: A biopsy can reveal the presence of cancer. So the doctor may take a small part from the lymph node of the neck, underarm, or even the groin.
• Other tests: If the doctor detects lymphoma, your child may need some other tests to identify its extent. These include some laboratory tests like CBC, liver and kidney function tests, a CT scan, PET-CT scan, an MRI, and some lung function tests. In addition, there might also be a heart evaluation using the echocardiogram (ECHO) or the multigated acquisition (MUGA) scan.
• Bone marrow aspiration: As stated before, in this test the doctor may take a part of the bone marrow to study the lymphoma cancer, one of the top childhood cancers.  

Treatment 

If the tests are positive, your child’s treatment options include chemotherapy, radiation therapy, immunotherapy, as well as bone marrow transplant.

This type of cancer and its treatments can take a toll on the body. Therefore, the doctor might recommend alternate relaxation therapies. This, in addition to palliative or supportive care for the patient.   

The most important thing to remember is that while you cannot do anything about genetic or birth-related cancers, you can work towards creating an environment that is not conducive to childhood cancer. 

Where to seek help if your kid has one of these types of childhood cancer

There are various centres in Singapore that can tend to your needs. They can provide diagnosis, tests, treatments, and counselling if your child has one of the types of childhood cancer we describe. 

1. Children’s Cancer Foundation (CCF)

CCF Community Office, VIVA-CCF Hub

Address: 8 Sinaran Drive, #03-01 Novena Specialist Centre Singapore 307470

Telephone: 6229 3701 | Facsimile: 6229 3700 | Email: ccfadmin@ccf.org.sg

Website: https://www.ccf.org.sg/ 

2. KK Women’s and Children’s Hospital 

Address: 100 Bukit Timah Road, Singapore 229899

Telephone: +65 6225 5554 | Email: centralappt@kkh.com.sg 

Website: https://www.kkh.com.sg/

Sources: IARC, American Cancer Society, Roswell Park, American Society of Clinical Oncology 

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