The therapy is particularly suitable for cancers located in sensitive areas like the brain, or near the eye or spinal cord, for example. ST PHOTO: NG SOR LUAN 

Proton beam therapy, an advanced form of radiation treatment that can target cancer tumours with greater precision and minimise damage to surrounding tissues and organs, should be available in Singapore by the first quarter of 2023.

The Goh Cheng Liang Proton Therapy Centre at the new National Cancer Centre Singapore (NCCS) building in Outram will start operations in the first quarter of 2023.

Two other centres in the private sector will also offer proton beam therapy at around the same time.

Mount Elizabeth Novena Hospital plans to offer the therapy from next February.

The Singapore Institute of Advanced Medicine Holdings (SAM), a new cancer centre in Biopolis Drive, is awaiting the go-ahead from the authorities to start offering it, possibly by the end of 2022, said its chairman and chief executive officer Djeng Shih Kien.

While conventional radiotherapy uses X-rays, proton beam therapy uses positively charged subatomic particles that allow for more precise targeting of cancer cells.

This causes less damage to nearby healthy tissues and organs, which means there are fewer treatment-related side effects.

The risk of developing secondary cancers due to radiation is also reduced, said Dr Soong Yoke Lim, deputy chairman and senior consultant at the radiation oncology division at NCCS. This is why it is recommended for patients below the age of 25, he said.

The therapy is particularly suitable for cancers located in sensitive areas such as the brain, or near the eye or spinal cord, for example.

Professor Robert Malyapa, director of SAM’s proton therapy centre, who has had experience treating patients with the therapy in the United States, said that unlike X-rays that pass through the tumour and then exit the body, protons deposit a burst of energy at the end of their path, which is known as the Bragg peak. There is no exit dose of radiation as the proton beam stops at the tumour.

Dr Soong added: “With conventional radiation, for example, it may come from such a direction that the areas that you don’t want to treat get treated.”

He said there is no difference between proton therapy and conventional therapy where cure rates are concerned, because the dose of radiation delivered to the tumour is similar.

Still, it was a no-brainer for Mr Peter Wong to send his then 21-year-old son Samuel for proton therapy in Taiwan in 2019, after he was diagnosed with stage one nasopharyngeal cancer in Singapore. Radiotherapy is the main treatment for this type of cancer.

Mr Wong said he claimed from Samuel’s critical illness insurance policy and paid $100,000 for the proton beam treatment alone. In Taiwan, his son went through 33 sessions of proton therapy for five days a week, as well as six weekly sessions of chemotherapy.

“I lost my sense of taste of sugar, salt, bitterness and sourness... Eating pepper was almost the same as taking a bite of chilli padi, and that happened for about six months after the treatment,” said Mr Samuel Wong.

His left ear was also affected as the tumour was located very close to the eustachian tube, which helps to balance the pressure between the inner and outer ear. He now experiences a permanent blocked-ear sensation as if he is on a plane, said Dr Soong, who is Samuel’s doctor.

Proton beam technology is costly. SAM spent around $85 million on its proton beam facility, Mount Elizabeth Novena Hospital put in close to $80 million for its facility, while NCCS invested $100 million on its system.

NCCS’ facility has four treatment spaces served by one particle accelerator, while the other two centres have one treatment space each.

Prof Malyapa said a course of proton beam treatment can consist of at least 25 to as many as 37 sessions, depending on the severity of the cancer. Each session at SAM will cost $2,800 to $2,900, said Dr Djeng.