S'pore's pint-sized fighter battles a genetic condition and bone cancer

PHOTO: S'pore's pint-sized fighter battles a genetic condition and bone cancer

SINGAPORE - Ms Agnes Tung has an incurable disease. But for years, the thing that bothered her most was how short it made her, which earned her nasty nicknames in school.

Now at 22, she is still a diminutive 1.38m woman who weighs only 38.5kg.

Her abnormally slow growth was flagged by a nurse during a school health screening when she was 12.

After a battery of tests at the National University Hospital (NUH), she was diagnosed with an extremely rare disorder called mucopolysaccharidoses type 6 (MPS VI), whose symptoms show up only during childhood.

People who have the genetic disease are unable to break down complex sugars called mucopolysaccharides, which then accumulate in cells and cause tissues and organs throughout the body to be enlarged.

It is not known how many people here have the incurable disease.

Associate Professor Denise Goh, head and senior consultant at NUH's division of paediatric genetics and metabolism, who is Ms Tung's doctor, said she has seen only one other case of MPS VI at the hospital.

Many medical problems

Ms Tung recalled vividly how, with her large head and distinctive-looking facial features, she was treated "like an alien" by her classmates in Jurong Primary School.

They did not cooperate when she was tasked to collect their homework and deliberately left her out of group discussions.

She said: "Initially, I was very sad, but after a while, I just let people say what they wanted."

MPS VI affects the skeletal system and results in a short stature and joint stiffness.

That, plus an unexplained leaky mitral valve, which separates the two left chambers of the heart, got Ms Tung exempted from physical education (PE) classes from the age of 12.

She did not mind as she was not particularly athletic because of the disease.

In fact, she was always the last person to complete the 2.4km run of the National Physical Fitness Award test and felt tired just carrying her schoolbag.

At 16, she was plagued by frequent throbbing headaches and was unsteady on her feet because her legs always felt like jelly.

These problems were caused by an accumulation of fluid in the cavities of the brain as a result of MPS VI. The hydrocephalus required the insertion of a device into her brain to drain the fluid into her abdomen and relieve the pressure on her brain.

Prof Goh said that substances accumulating in Ms Tung's skull also caused it to expand and pinch her spinal cord, weakening the nerves controlling her legs.

The skull was then shaved in a second operation that year, in which she was supposed to sit two O-level examinations.

Ms Tung, a Normal (Academic) student, took a year off school and completed her O levels at the age of 18. She reasoned: "It is never too late because although my journey is longer, I still end up at the same destination."

But fate dealt her another cruel blow in October 2011 when she was diagnosed with osteosarcoma, a form of bone cancer that is unrelated to her genetic condition.

A magnetic resonance imaging scan showed a 4cm to 5cm abnormal growth in her shin bone below her knee joint, which she could feel with her fingers.

It caused her excruciating pain and kept her up at night.

Dr Chetan Anil Dhamne, associate consultant at NUH's division of paediatric haematology and oncology, said United States data has shown that four out of every million people under the age of 24 have osteosarcoma.

This cancer is most common during puberty years when bones are growing most rapidly, he explained.

He concluded that Ms Tung's aggressive-looking lesion had eroded her shin bone and spread into the tissues outside this bone.

To treat her cancer, she had two cycles of chemotherapy before having surgery to remove her entire right knee and portions of her thigh and shin bones. These were replaced by a mega-prosthesis.

She then continued with four cycles of chemotherapy, gritting her teeth through side effects such as nausea, vomiting and appetite loss.

When a social worker offered Ms Tung the option to wear a wig after she shaved her head bald to stem hair loss, she turned it down.

She said: "I didn't feel the need to as I didn't want to feel out of place among the other children with cancer."

The ever-thoughtful "big sister" made cards filled with words of encouragement for two pre-school cancer patients whom she heard crying in her ward at night.

Dr Chetan said her cancer is in complete remission and the risk of it recurring now is under 30 per cent.

But her MPS VI has also led to other problems in recent years: Cloudy corneas, a reduced lung function and, most recently, obstructive sleep apnoea.

Prof Goh said MPS VI caused her to have a short neck and a narrowed upper airway, which led to the apnoea. A small ribcage also meant her lung reserves are low.

She now sleeps with a continuous positive airway pressure machine, which pushes air into her airway and lungs through a mask she wears over her nose.

Brave and optimistic

Ms Tung's elder sister, 24-year-old medical technologist Cheryl, calls her "a very brave and optimistic person".

Cheryl has long become used to strangers staring at them and does not mind taking her younger sister out to the mall on weekends.

Ms Tung now uses a walker at home and a wheelchair in public places because of her knee prosthesis. She is training herself to be more independent at home.

She told Mind Your Body proudly that she is picking up Web design skills from home and can do simple chores such as washing her own utensils and putting away groceries.

She is one of 20 patients, aged 15 to 33, who are taking part in Project Dreamcatchers 2014, a photography exhibition organised by the National University Hospital to create awareness about childhood chronic illnesses.

It opens tomorrow at the Singapore Management University de Suantio Gallery, Level 1, and will run from 11am to 8pm daily until Aug 10. Admission is free.


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