Royal Free London NHS Foundation Trust, based in Pond Street, Hampstead, has paid out the cash for claims since 2019, according to an investigation by Medical Negligence Assist.
The trust serves a population of more than 1.6 million people across 70 sites in north London and Hertfordshire and is one of the biggest providers of cancer care in the UK.
In the last five years 82 claims regarding misdiagnoses were settled by the trust, the research found.
The trust paid out a total of £26,514,461 in damages.
The highest amount came in 2022/23, standing at £10,821,781.
The research found government body NHS Resolution said the most common outcome for misdiagnosis claims was unnecessary pain, lodged 12 times, with the trust paying £1,701,656 in compensation, followed by additional operations, which saw 11 claims submitted.
The highest number of claims came in 2019/20, when 21 claims were made against the trust.
A year later, this number fell to 14 claims.
The service has seen the number of claims rise over the past year compared to 2022/23, with a total of 19.
Gareth Lloyd, medical negligence solicitor for JF Law (which owns the Medical Negligence Assist brand), said misdiagnoses are becoming “alarmingly common”.
He added: “Misdiagnosis is an all-embracing clinical negligence case type and covers a wide range of clinical situations from the simple diagnosis of a fracture to potentially fatal cancer diagnoses.
“These cases can be a matter of life and death, and whether someone lives or dies will be determined by the success of the diagnosis.”
A spokesperson for the Royal Free London said: “We would like to apologise to any patient whose treatment has fallen below the high standards that we expect at the Royal Free London.
“The vast majority of our patients have a positive experience but when this is not the case, we support our staff to learn from their experiences to reduce the risk of mistakes happening again.”
