A businessman and philanthropist has donated £4.5m to The Christie cancer hospital in Manchester.
The money will support the hospital's high-energy proton beam therapy (PBT) clinical trial for patients with mouth and throat cancer.
Ian Taylor, who was treated for the disease in Switzerland, said he "passionately believes" PBT can help cure such cancers.
The Christie began treating patients in the NHS's first PBT centre in December.
High-energy PBT is a specialist form of radiotherapy that targets certain cancers more accurately than other treatments, increasing success rates and reducing side effects.
The donation is part of £15m pledged by Mr Taylor on behalf of The Taylor Family Foundation to head and neck and proton beam therapy cancer research in the UK.
Mr Taylor is chairman of the Vitol Group, the world's largest independent energy trader.
What is proton beam therapy?
It uses charged particles instead of X-rays to deliver radiotherapy for cancer patients.
It allows high-energy protons to be targeted directly at a tumour, reducing the dose to surrounding tissues and organs.
In general, patients suffer fewer side effects compared to high energy X-ray treatments.
It can be used to treat spinal cord tumours; sarcomas near the spine or brain; prostate, lung and liver cancer; and some children's cancers.
Sources: NHS England Cancer Research UK