Women have been urged to attend breast cancer screening tests, as figures show almost 35,000 in Norfolk and Waveney did not go to their last scan.
Between the ages of 50 and 70, women are invited for breast screening every three years in a bid to catch and diagnose cancer quicker.
But figures show thousands of women are not taking up the offer, with the rate declining both locally and nationally.
Of the 146,545 women in Norfolk and Waveney invited for a scan in the three years up to March, 77.1pc accepted - meaning 33,450 women went without.
While district rates hovered between 70pc and 80pc, Norwich had the lowest take-up rate, at 75.5pc, while north Norfolk had the highest, at 78.7pc.
Addie Mitchell, clinical nurse specialist at the charity Breast Cancer Care, said: 'Uptake of routine screening invitations in England has been gradually slipping year-on-year.
'These troubling figures show we're now only a hair's breadth above the minimum standard.
'While screening is not a one-stop shop, as symptoms can occur at any time, mammograms remain the most effective tool at our disposal for detecting breast cancer at the earliest possible stage.'
Nationally, 72pc of women attended their last check, while just 70.5pc of those invited in the 12 months to March had attended within six months - the lowest level since 2007, when the programme began.
While the UK National Screening Committee says the minimum acceptable level is 70pc, the NHS is expected to achieve 80pc.
Across our region's Clinical Commissioning Groups (CCGs), the take-up rate has fallen over the last few years.
In Norwich and south Norfolk it is at its lowest since 2012/13, and the lowest since 2011/12 in Great Yarmouth, Waveney and north Norfolk.
West Norfolk has bucked the trend, with the percentage rising slightly from 77.4pc in 2016/17 to 77.5pc this year.
Dr Anne Mackie, director of screening at Public Health England, said it was 'concerning' that uptake has fallen, particularly among younger women invited for their first test.
She said: 'We are working hard with NHS and local community healthcare colleagues to understand why this might be and to make appointments as easy as possible to attend for all women who want to get screened.'
Don't leave it late
Lucy Thompson, 42, of Hethersett, discovered she had primary breast cancer on November 23 last year, and began chemotherapy just after Christmas 2017.
One year on, and after six cycles of chemotherapy and a month of radiotherapy, she is clear of cancer.
While she found her lump herself – being too young for the screening test – Mrs Thompson has urged all women who are eligible to attend their appointments.
'I would encourage anybody to go through the screening, because if you find it early your prognosis can be so much better,' she said.
'I can't understand why anybody would not have the screening, because it can potentially save your life.
'The care you get in Norwich is fantastic and they have a tremendous breast cancer care team, but if you can find it earlier you may get less invasive treatment.'
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