West Hertfordshire Teaching Hospitals NHS Trust said the new facility would provide “modern facilities” along with more space for “innovation, research and training”.
“Modern cancer care increasingly relies on the support of a range of on-site medical and surgical services, including Accident and Emergency and critical care,” it added.
“With plans already approved for a new Watford General Hospital, this proposal would add world class cancer services to the site, creating a centre of excellence.”
The elected Mayor of Watford, Peter Taylor, said although he was pleased about plans to relocate Mount Vernon, he was concerned about timings.
“The rebuild of Watford General is needed now more than ever,” he said.
“Despite being shovel-ready, this project has been delayed with construction not scheduled to even start until 2032.
“The rebuilding of Watford General should be a top priority for the government and they need to deliver the funding needed for this now.”
A Department of Health and Social Care (DHSC) spokesperson said: “This government inherited a New Hospital Programme that was neither deliverable nor affordable.
“We have an honest and realistic funding plan and timetable to deliver the rebuild of Watford General Hospital, ensuring it is ready to enter construction as quickly as possible and that taxpayers get maximum value for money.
“A public consultation will begin soon for people to have their say on the future of the Mount Vernon Cancer Centre.”
People are being invited to join a public consultation, external that runs from 19 January to 26 March.