There are to be 300 more radiographers employed by the NHS in England, ministers have announced as experts have warned of a "crisis" in the diagnostic workforce.
Health Secretary Jeremy Hunt has made the pledge as part of the NHS's Cancer Workforce Plan.
Charity Breast Cancer Now said that the diagnostic workforce is at "crisis capacity".
The news comes after health inspectors launched a national review into radiology reporting in the NHS after they discovered that in one hospital junior doctors were left to interpret chest x-rays, including those for suspected lung cancer.
At least three patients had come to serious harm as a result, the Care Quality Commission found.
Now Mr Hunt has announced that additional cancer specialists will be employed by the NHS to speed up cancer diagnoses and get more people into treatment more quickly.
This includes 300 more reporting radiographers - specialists who use x-rays and ultrasound to identify certain cancers, including breast and lung.
The plans, to be unveiled at the Britain Against Cancer conference, will also see an additional 200 clinical endoscopists - clinical experts who use tiny cameras on a long, thin, flexible tube to investigate suspected cancers, such as bowel and stomach, inside the body.
It is hoped the new staff will be trained by 2020, according to Health Education England's (HEE) new Cancer Workforce Plan.
The plan outlines that HEE will train more staff in the clinical disciplines where there are shortages
The announcement comes amid burgeoning demand on the health service.
The Department of Health said that the NHS carried out 21.4 million diagnostic tests, seven million more than in 2010.
Compared with September 2011, in September 2017, the NHS in England performed almost 462,000 more diagnostic tests. This including endoscopy tests, MRI scans, CT scans and non-obstetric ultrasound tests.
The Department said 6,500 cancer patients are alive today who wouldn't be had mortality rates stayed the same as 2010.
Mr Hunt said: "The NHS has made amazing progress in diagnosing and treating cancer - it's incredible that 6,500 more people are alive today who would not have been had mortality rates stayed the same as in 2010.
"We want to save more lives and to do that we need more specialists who can investigate and diagnose cancer quickly. These extra specialists will go a long way to help the NHS save an extra 30,000 lives by 2020."
The news comes as a group of MPs warned that NHS England will "struggle" to achieve ambitious plans to improve cancer care in England without immediate "corrective action".
The All Party Parliamentary Group on Cancer made recommendations on the health service's Cancer Strategy surrounding workforce planning, extra "transformation" funding for frontline services and delays in data publication.
MP John Baron, chairman of the group, said: "Progress has been made in some areas, but overall a lack of audit and workforce planning, and the delay in funding to frontline services from NHS England, threaten to derail the Cancer Strategy. Corrective action now needs to be taken."
Commenting, Fiona Hazell, director of policy and engagement at the charity Breast Cancer Now, said: "While we have seen significant advances in recent decades, we believe that progress on breast cancer is now stalling.
"This worrying frontline report highlights growing areas for concern that continue to hinder progress on cancer, including workforce shortages, funding delays and a lack of accountability and data collection.
"These delays in progress are directly affecting patient care, with a diagnostic workforce already at crisis capacity also likely to impact screening, early diagnosis and, ultimately, patient outcomes.
"The long-anticipated Cancer Workforce Delivery Plan is very welcome, but will now require immediate funding and commitment to deliver its ambitions across seven urgent areas, including diagnostic radiography and radiology.
Dr Fran Woodard, executive director of policy at the charity Macmillan Cancer Support, added: "We are particularly concerned about the lack of progress made over the past couple of years in ensuring the cancer workforce is fit to meet increased future demand. Doctors and nurses working in cancer care have told us that they are currently seriously overstretched, and this is beginning to affect patient care."
Cally Palmer, national cancer director at NHS England, said: "New figures suggest that thanks to improved NHS cancer care an extra 2,100 people will survive cancer than would have done just a year ago. That means more families able to celebrate the Christmas holidays together."
Copyright (c) Press Association Ltd. 2017, All Rights Reserved. Picture (c) Rui Vieira / PA Wire.