MPs have lobbied the Secretary of State for Health to look into hundreds of "inexcusable" mistakes made in urgent cancer referrals at south west Hertfordshire hospitals.
Jeremy Hunt met with five MPs from the area yesterday after it emerged that more than 800 patient cases have had to be reviewed because of problems at West Hertfordshire Hospitals NHS Trust.
Yesterday the trust, which runs Watford General Hospital as well as sites in St Albans and Hemel Hempstead, said it had initiated an investigation after discovering systemic problems with cancer referrals.
In November it found that patients referred to its hospitals with suspected cancer symptoms who missed their first appointment were not being offered a second before being discharged - as is the practice outline by NHS guidelines.
This led to a review of 810 cases dating back to January 2010 where a second appointment was not offered. The trust has so far found no problem in 686 of them.
However it found two patients had died since their referral and the trust said a delay in the referral may have contributed in one of these cases.
In the case of third patient the trust found the problems had caused a delay in their cancer diagnosis, but the condition was still caught at an early and treatable stage.
The trust is currently still reviewing 121 cases.
Following the revelations, MPs Richard Harrington, David Gauke, James Clappison, Mike Penning and Anne Main met Mr Hunt to discuss the referral problems.
They pressed the minister to take a close interest in the case to make sure it never happens again.
Watford MP Richard Harrington said: "This is clearly an inexcusable situation and it should have been picked up long before the new management team took over.
"I am working with my Hertfordshire colleagues to ensure this is being given the attention it deserves in Parliament and at the Department of Health, as well as ensuring this has not happened in other areas."