It always comes as a shock when a child is found to have cancer.

'Childhood cancers usually grow much more rapidly and kill quickly. If the cancer is left untreated, the child will die within six months,' said Associate Professor Allen Yeoh.

He is the medical director of Viva-University Children's Cancer Centre at University Children's Medical Institute at the National University Hospital.

Besides its sudden toll on a child's body, cancer invariably causes shock through its devastating emotional impact on the child's family.

Mr Anwar Ajiman, 40, whose eight-year-old daughter Aina Syara has the blood cancer leukaemia, said: 'At first, my wife and I couldn't accept what the doctor told us.

'We didn't believe it because it was so sudden.'

Ms Chee Wai Yee, executive director of Children's Cancer Foundation, said: 'Cancer is not just a medical condition. It affects the patient and his entire family.'

Aina is now receiving treatment for her illness.

There are many types of childhood cancer and common ones in Singapore include acute lymphoblastic leukaemia, brain tumours, lymphoma, germ cell tumours and neuroblastoma.

The Singapore Childhood Cancer Registry, in its first report, said 1,103 children here were diagnosed with cancer between 1997 and 2005.

About half of all childhood cancer occurred in children below the age of five. For most childhood cancer, the causes are unknown.

Some children, like those with Down's syndrome, have an increased risk of leukaemia.

When asked what symptoms children with childhood cancer may display,

Dr Chan Mei Yoke, a senior consultant in paediatric haematology/oncology at KK Women's and Children's Hospital, said: 'The symptoms vary, depending on where the tumour is and how young the child is.

'For leukaemia, the symptoms include unremitting fever, pallor, bruises and lethargy.'

Leukaemia arises from the bone marrow and prevents normal bone marrow from producing white and red blood cells. It also causes low platelet count. The result is recurrent infections, bodily weakness and bleeding in the gums, nose and skin.

As for brain tumours, Prof Yeoh said these 'may cause progressive vomiting and headaches and may also cause the child to squint his eyes or tilt his head to one side'.

He added: 'Any squint of the eyes or head tilt in children needs to be reviewed by a doctor. Some children may start regressing, such as becoming unable to walk.'

Lymphoma causes the lymph nodes in the neck, armpit, groin, chest or abdomen to swell, with painless but rapidly enlarging lumps appearing.

Meanwhile, germ cell tumours and neuroblastomas show up as lumps in the child's body.

Chemotherapy, surgery and radiation therapy are among the treatment options for cancer.

For example, leukaemia and lymphoma are treated with chemotherapy while brain tumours require surgery to remove the tumour, followed by radiation therapy and chemotherapy.

Child patients with leukaemia and lymphoma have more than 80 per cent chance of being cured while survival rates for brain tumour cases range from less than 10 per cent to 80 per cent, depending on the type.

Asked if childhood cancers are more aggressive than cancers in adults,

Dr Chan said: 'They are more aggressive because the body's cells are more primitive. But this also makes childhood cancers more responsive to treatment.'

Children usually get blastomas and sarcomas whereas adults get carcinomas.

Blastomas are tumours which arise in embryonic tissue while sarcomas are malignant bone tumours. Carcinoma refers to cancer that begins in the skin or in tissues that line or cover body organs.

Dr Yeoh said: 'Childhood cancer resembles tissues in a normal growing foetus. Hence, it grows rapidly like a foetus. The difference is normal foetal tissues know when to stop growing. Childhood cancers do not.'

Leukaemia can occur in children from birth to 18 years old, with the peak age of occurrence between two and six years old.

Brain tumours in children often occur from birth to 10 years old. Neuroblastomas in children usually occur under five years of age while germ cell tumours and lymphoma occur in older children and adolescents.

Doctors whom Mind Your Body spoke to said survival rates for children with cancer have improved over the years.

In Singapore, two in three children diagnosed with cancer are long-term survivors.

Dr Chan said: 'If the child is cured and does not have other medical problems due to the cancer or its treatment, his lifespan would be the same as everyone else's.'

However, some childhood cancer patients may develop cancer in adulthood, as some chemotherapy agents and radiation treatment can cause cancer years later.

Parents of children with cancer receive ample support here.

When a child is diagnosed with cancer, the hospital's team of nurses, doctors and social workers are on hand to help.

These medical professionals will tell the young patient the truth of their illness and prepare them for what is to come either through counselling or therapeutic play. They will also discuss with the child's parents the diagnosis, treatment and possible outcomes.

The Children's Cancer Foundation has also tied up with the National University Hospital and KK Women's and Children's Hospital to provide patients and their families with counselling, therapeutic play, parents' support groups, palliative care and other services.

Ms Chee of Children's Cancer Foundation said: 'We hold regular chill-out nights in the hospitals for parents who stay 24/7 with their children. We get them their favourite food and get them together to talk. It's to let them know they're not alone.'

junec@sph.com.sg

This article was first published in Mind Your Body, The Straits Times.