THE number of requests by GPs in Scotland for a potentially life-saving blood test which can detect ovarian cancer early has increased significantly since a shake-up in the referrals process three years ago.

However, the rise in requests varies massively between health boards - soaring five-fold in NHS Borders but actually declining in the Western Isles - amid fears from cancer campaigners that many patients are still waiting too long, and "red flag" symptoms are being dismissed by doctors for more common conditions such as irritable bowel syndrome (IBS).

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Figures obtained by the Herald under freedom of information show that the number of CA125 tests carried out across Scotland climbed 39 per cent between 2013/14 and 2016/17, from 47,421 to 65,894. The check analyses the blood for traces of a protein biomarker which tends to be elevated in cases of ovarian cancer.

In 2013, Scotland became the only part of the UK to introduce guidelines instructing GPs who suspected a patient may have ovarian cancer to order a CA125 test and ultrasound simultaneously in order to speed up diagnosis. Elsewhere, GPs have to wait for CA125 results before referring a woman for ultrasound.

Read more: Warnings GPs missing ovarian cancer symptoms 

Since then, requests for the test have shot up 447 per cent in the Borders - from 1,216 to 6,649 last year - while Dumfries and Galloway and Lanarkshire health boards have also experienced hikes of more than 50 per cent. Most of the health boards which provided data - NHS Grampian and Orkney did not - recorded increases of around 23 to 27 per cent. However, in NHS Western Isles the number of requests fell, from 335 to 309, while in Fife the uplift was just 11.4 per cent.

The test is important because it is one of the quickest and cheapest ways to spot potential ovarian cancer cases. GPs are urged to order the test if a patient - especially women who are post-menopausal or over-50 with no prior IBS - present with persistent bloating, abdominal pain, disrupted bowel movements, feelings of fullness and loss of appetite.

However, research by the charity Target Ovarian Cancer has shown that more than a third of women in Scotland diagnosed with ovarian cancer had visited their GP three times with symptoms before finally being referred for tests.

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Rebecca Rennison, the charity's director of public affairs, said: "It's very important that it gets picked up early. The earlier the diagnosis the better the chances of survival. One of the most frustrating things for us is that IBS diagnosis.

"There is still this myth that there aren't symptoms, but there actually is a clear evidence base for the symptoms - they're out there in the guidelines. If you've got a woman presenting with IBS-like symptoms over 50 there should be alarm bells, because it's not going to be IBS for the first time over 50."

There were 349 deaths from ovarian cancer in Scotland in 2016 - the lowest since current records began in 1991. However, survival lags behind Europe and more common cancer types, such as breast. Late diagnosis is partly to blame, with the UK's GP "gatekeeper" model believed to be a factor in slowing down the referrals process.

A major clinical trial led by University College London is also examining whether routine CA125 screening among women over 50 can cut mortality from the disease. Initial results in 2015 suggested it would, saving around 15 lives for every 10,000 women screened, but more thorough data is expected in 2018.

The test is not perfect - it can produce false negatives, wrongly suggesting a woman is cancer-free, and flags up other conditions such as endometriosis. It is also unclear whether routine screening would do more harm than good, by leading to unnecessary surgery which it itself carries risks of infection or damage to other organs.

Ms Rennison added: "The more we understand about the disease the more opportunities there will be to look at new diagnostic tests and how we can diagnose it differently.

"For the moment, CA125 is what we have - together with ultrasound - and we have to make it work as well as we can, but it would make a big difference to have a more accurate test."

Health Secretary Shona Robison said: “Early detection of all cancers is crucial and we remain committed to building on the progress already achieved. Through our Detect Cancer Early programme, we aim to increase the proportion of cancers that are detected at the earliest stages.

"In 2018, the programme will place further focus on the overall benefits of early detection for all cancers through a new pan-tumour awareness campaign and it will further encourage anyone with concerns to visit their GP.”