Singapore is investing close to $100 million on a proton beam therapy system to treat cancers which causes much less damage to healthy tissue than current radiation therapy.

With about three in five cancer patients requiring radiation, the National Cancer Centre Singapore (NCCS) has been studying the technology for a decade, but cost and size have been major inhibitors.

The machine will occupy three floors in the basement of the new cancer centre at the Outram campus when it opens in 2021, according to NCCS director Soo Khee Chee who yesterday announced that the machine would be from Hitachi. The Japanese company beat six other firms to clinch the deal.

It will be the first such system in South-east Asia.

Initially, it will be used on children and young adults, for cancers in the head, and for patients who have had radiation therapy previously and suffered a relapse.

Dr Fong Kam Weng, who heads radiation oncology at the NCCS, said it is particularly good for treating brain cancer, especially in children.

With current treatment, “damage to the brain is inevitable” and survivors suffer a range of side effects, including mental retardation, stunting and hormonal imbalance.

It will also be used for people who have had a relapse because radiation raises the risk of secondary cancers developing in the area irradiated.

Professor Soo said that with proton beams, such side effects are “significantly reduced”. The chances of brain damage and retardation drop to less than half and secondary cancers to about one-eighth, compared to conventional X-rays.

The centre expects to treat 150 patients in the first year before building up to about 1,000 patients a year. Patients need 20-30 sessions, with the actual radiation treatment lasting less than two minutes each time.

Dr Fong said the NCCS will run clinical trials for other cancers such as for prostate, oesophagus and left breast, which is near the heart, to compare it with current treatment.

Dr Fong added that the NCCS might also try to see if higher doses can be given, as they can be more effective in killing cancer cells.

The Hitachi system will be the latest model available in 2021. An accelerator produces the proton beam, which is channelled to any of five rooms. Four will have revolving gantries that can shoot the beam from different angles and one will have a fixed beam. The gantries weigh 160 tonnes each, and have to be assembled on-site.

Prof Soo added that generally, one machine caters to a population of 25 million. Asked why more cancer centres do not have such technology, he said: “It’s not easy to find $100 million.”

Half the money will come from a $50 million donation from the Goh Foundation, set up by Nippon Paint founder Goh Cheng Liang. It will be the most expensive piece of equipment at the new NCCS that, excluding the proton beam, is expected to cost $800 million.