Patients whose operations are cancelled at the last minute by the Leeds Teaching Hospitals NHS Trust are increasingly having to wait longer than a month for them to be rescheduled.
The Royal College of Surgeons has blamed "enormous pressure" on the NHS for the long waits faced across England, saying it is unlikely there will be a reduction in cancelled operations any time soon.
The data covers cancellations that were due to non-clinical reasons, such as bed or staff shortages.
NHS rules say non-urgent operations, such as hip or knee procedures, that are cancelled at the last minute should be rescheduled to a date within a maximum of 28 days.
However, of the 362 patients who had their surgery cancelled by the Leeds Teaching Hospitals NHS Trust in the three months to June, 23 per cent were not treated within 28 days.
This was an increase on the same period last year, when 13 per cent of patients weren't treated within 28 days , and gives it one of the worst rates in the country.
According to Professor Cliff Shearman, vice president of the RCS, patients are likely to suffer from anxiety if their procedures are cancelled.
He said: “Having an operation that has been planned for months cancelled at short notice can be very stressful for patients and their families.
"Alongside practical considerations such as wasted time off work and rescheduling the surgery, patients will have to deal with the mental anguish of preparing for surgery all over again.
“They will also have to endure waiting longer in pain and discomfort, possibly unable to work or complete day-to-day tasks for themselves. In some cases, their condition may worsen."
Professor Shearman also warned that the figures could be disguising the true scale of cancellations, as they do not include those cancelled at more than 24 hours notice.
A last-minute cancellation is defined as being either on the day that a patient was due to arrive, after the patient has arrived, or on the day of the operation itself.
If a trust is unable to reschedule the operation within 28 days, it must instead fund the treatment with another hospital.
It also forfeits its payment from the NHS Clinical Commissioning Group that funds healthcare in the area.
There were 18,806 last minute cancellations across England in the three months to June.
Of these, 11 per cent of patients did not have their operations rescheduled within 28 days.
This rate is the second highest it has been since 2005, surpassed only in the preceding three months between January and March of this year, when it reached 12%.
"This will undoubtedly be down to the enormous pressures the NHS is facing", Professor Shearman said.
"These include not enough free beds in hospitals, difficulties tackling the backlog of operations that built-up over the winter, and now coping with a very busy summer thanks to record temperatures."
A spokesman for NHS England said: “Only a small minority of operations are cancelled on the day, while 15,000 fewer people now wait a year for their operation compared with 2010.
“New guidance issued to trusts recently will see local health service leaders allocate extra funding to community services, like district nursing teams and outreach clinics, to help them care for more patients, freeing up hospital beds and staff to reduce surgery waiting lists.”