Health experts have warned that the increase in cancer patients at a hospital serving the borough is outstripping the number of specialist doctors hired to diagnose and treat them.

But the Barking, Havering and Redbridge University NHS Trust (BHRUT) says that, in spite of this challenge, it is the only trust in London to be meeting the national 62-day cancer treatment target – and has done so for almost 18 months.

A report released by the Royal College of Radiologists (RCR) shows that number of full-time consultant oncologists serving Queen’s Hospital, in Romford, had risen from 7.9 in 2013 to 9.9 in 2018.

However the number of suspected cancer patients at BHRUT has almost doubled over that time period.

The RCR’s Dr Tom Roques said: “The UK is seeing more and more fantastic innovations in cancer treatment - from the introduction of new immunotherapy drugs to the NHS’s first high-energy proton beam radiotherapy centre.

“Clinical oncologists are vital to the rollout of these new therapies but we do not have enough of them and our workforce projections are increasingly bleak, which begs the question ‘what kind of service will we be able to provide for our patients in future?’”

Dr Roques said the RCR’s report shows cancer centres are “under immense strain”.

He added: “Some centres have seen a reduction or stall in consultant numbers and many are desperate but failing to recruit, predominantly because we do not have enough consultants in training.”

A BHRUT spokesman told the Recorder that the use of consultant oncologists can be a relatively “blunt indicator” and that Queen’s hospital has a team of more than 40 doctors at all grades working across its oncology and haematology services.

The trust has also invested in two Halcyon and an Edge radiotherapy machines – making it among the most advanced cancer treatment centres in the capital.

Dr Sherif Raouf, the trust’s divisional director of cancer and clinical support, said: “These figures highlight the huge challenges which exist across the country.

“It is a difficult picture, but it makes our recent success in maintaining our performance even more gratifying.

“It’s thanks to fantastic work from colleagues across our Trust and beyond that, our GPs.

“Some of our specialties have seen increases in numbers of referrals by up to 30pc in the last year alone, so we are proud that we are continuing to hit the national benchmark target, while making huge improvements to the quality of our service too.”

The RCR’s report points to a growing staffing crisis across the country, with predictions that by 2023 the NHS workforce will be down on the number of required cancer consultants by 22pc.

The RCR says a nationwide shortage of oncologists, the doctors who lead cancer diagnosis and treatment, is having a detrimental impact on patients.

One in six cancer centres across the UK now have fewer consultant oncologists than in 2013, the report claims.

But almost 1,000 people are diagnosed with cancer every day, the RCR says, and demand for radiotherapy and chemotherapy is rising.

The study found the UK is now lacking at least 184 clinical oncologists - the minimum number needed to fill vacancies and cover the extra hours doctors are working to treat patients.

An NHS spokesman said: “The NHS has published plans to recruit an additional 1,500 staff across seven priority cancer specialisms by 2021, and the size of that workforce has already grown by 803 since 2017.”

A Department of Health and Social Care spokeswoman said the Government was “expanding medical training places by 25pc and we will also launch a workforce implementation plan later this year to support the NHS with the staff it will need”.