Scientists develop gene test to tell if blood cancer drugs will work

Scientists have developed a test to identify which blood-cancer patients will benefit the most from a drug that can stop their cancer from returning. The test, which looks for genetic clues in cancer cells, can identify the ten per cent of patients who see little effect from life-saving lenalidomide.

This could spare them needless side effects such as exhaustion, infections and a higher risk of other cancers, although experts need more data before they know if it is safe to stop using the drug.

But it also helps to spot patients who may need other medicines alongside lenalidomide, and gives peace of mind to those most likely to benefit.

The test is so helpful that experts are calling for it to be used to guide treatment for the 6,000 Britons diagnosed with myeloma – a type of blood cancer – each year.

Many myeloma patients take lenalidomide for up to a decade to try to keep their disease under control.

‘For most, the drug is well tolerated, but some suffer side effects like feeling tired or being prone to infections,’ says Dr Martin Kaiser, consultant haematologist and clinical scientist at London’s Institute of Cancer Research.

‘Some take it for up to a decade. A common question they ask is ‘Do I really have to keep taking this drug?’ and ‘How much is it actually helping me?’ ‘

Some studies have shown that taking the drug for a long time may be associated with an increased risk of some cancers, including Hodgkin lymphoma. Myeloma affects a type of blood cell called plasma cells that help fight infection and are made in the bone marrow – the spongy tissue in the centre of the bones.

It causes plasma cells to over-multiply, producing a build-up of faulty cells in the bone marrow, which can damage the bones.

This also disrupts the production of other blood cells, stopping the body from effectively fighting infections. The disease is sometimes called multiple myeloma as it affects bone marrow in several areas, such as the spine and ribs.

To treat myeloma, chemotherapy and steroids are given to kill faulty cells, but the vast majority of patients will see the disease return within a few years.

Lenalidomide blocks the development of abnormal cells, keeping the cancer at bay for about three years on average, compared to two years without treatment. ‘But there’s huge variation – for some it’s a decade, for others a year,’ says Prof Kaiser.

Previously, there was no way of knowing who would not respond to the drug. But the study has identified a group of ‘super-responders’, who are 40 times more likely to see their cancer stop growing than others.

In the study, researchers at the Institute of Cancer Research and University of Leeds performed the new test on 556 recently diagnosed myeloma patients. It involves taking a sample of bone-marrow tissue via a needle in the back, under local anaesthetic, and looking for patterns in the cancer DNA.

The scientists found that a third of patients with a particular pattern lived for an average of just short of five years on lenalidomide, compared with an average of about three. Meanwhile, roughly one in ten with another genetic pattern did not benefit as much – with outcomes similar to those not taking lenalidomide.

‘We’re trialling new combinations of drugs for this group which are proving beneficial,’ says Dr Kaiser. ‘Those who may not be as likely to benefit may want to consider options such as clinical trials testing new drug combinations.’

The test, which looks for genetic clues in cancer cells, can identify the ten per cent of patients who see little effect from life-saving lenalidomide. This could spare them needless side effects such as exhaustion, infections and a higher risk of other cancers (stock photo)

Experts say it would be feasible to use the test in this way, because it is already widely available in the NHS. ‘Many specialists use it after diagnosis to give patients an idea about how aggressive the cancer is,’ says Prof Kaiser. ‘It helps us advise patients better when it comes to their treatment.’

Cecelia Brunott, 46, from Surrey, was diagnosed with myeloma in 2020 and has been taking lenalidomide since September 2021, following a bone marrow transplant.

She volunteered to undergo the test and results showed that her cancer was not genetically high-risk.

‘My cancer protein levels have come down since being on lenalidomide and are no longer measurable,’ she says. ‘The test has given me peace of mind to know that the drug is helping keep the cancer away for as long as possible.’