A borough health chief has apologised for long waits for key diagnostic tests.
NHS Wigan Borough Clinical Commissioning Group (CCG) is struggling to meet targets for some vital tests, which can be used to diagnose cancer and other serious conditions.
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In February, 1.09 per cent of patients waited more than six weeks and Wigan borough met the one per cent target just twice in the previous 12 months.
A total of 5,794 people were waiting for 15 diagnostic tests in February - 273 more than the same month last year.
Of the 1,090 people waiting for an MRI in February, 17 waited for more than six weeks, including three for more than 13 weeks - a performance of 1.56 per cent.
New figures show 6.8 per cent of people waited more than six weeks for a colonoscopy, 5.47 per cent for gastroscopy, 3.45 per cent for flexi sigmoidoscopy and 2.11 per cent for cystoscopy.
But the performance was much better for others, with no-one waiting for six weeks for five diagnostic tests.
Dr Tim Dalton, CCG chairman, said: “We are sorry that patients are waiting longer than we would hope for colonoscopy tests and MRI scans.
“We will continue to work closely with the providers of the services to make sure everything possible is being done to bring the wait times down.
“In the meantime, patients would be advised to contact their GP practice should their symptoms worsen whilst they are waiting, especially if it is more than six weeks since they saw their GP about their symptoms.”
Changes to the tests available for suspected bowel cancer are thought to have led to increased demand for colonoscopy. Wrightington, Wigan And Leigh NHS Foundation Trust is reviewing its referral procedures and a new test could be rolled out.
Steps are being taken to improve waiting times for MRI scans at Salford Royal NHS Foundation Trust.