Cancer patients face increased death risks by putting off a diagnosis over fears attending a GP or hospital exposes them to Covid-19.
New research shows many patients are not being referred for specialist treatment because they fear picking up Covid-19 in healthcare settings, meaning necessary interventions are not happening as regularly as before the coronavirus outbreak.
Professor Mark Lawler, who is leading cancer research at Queen's University Belfast, has warned more cancer patients will die as a result of not seeing a doctor urgently.
"There will be excess deaths in the Irish situation," he told the Sunday Independent.
"It is difficult to predict what those numbers will be."
However, he said UK and international research can be used as a guide.
Prof Lawler has found Covid-19 will have a direct impact on mortality rates in people with cancer in the UK.
The study, carried out in conjunction with University College London and the UK's health data research hub for cancer, estimates there could be at least 6,270 additional deaths in newly diagnosed cancer patients alone within a year. This number could rise to an estimated 17,915 additional deaths in a year if all people currently living with cancer are considered.
He said the research model can be applied to other countries and shows more cancer patients in Ireland will die than otherwise would have been the case if the Covid-19 crisis had not emerged.
"We believe this is a universal phenomenon," Prof Lawler said. His work with colleagues had already identified "displacement" of cancer awareness in Eastern European health systems.
"What we found was on average cancer referrals, so the early warning system when you are referred from a GP to a specialist, were down 76pc from pre-Covid-19 levels. That is when red flags are raised and people follow up on a lump or bleeding they are concerned about so it shows the early warning system isn't working.
"Chemotherapy appointments and attendances, a proxy indicator of how healthy the cancer service is, were down 60pc. Those two things worried us."
"You would expect a similar thing to happen [in Ireland]. Obviously the numbers would not be the same given the population difference in size, but certainly one of the things we are encouraging people to do is to take our model and use it on their own population."
Prof Lawler said the findings show cancer and other underlying health conditions are at risk of adding to the escalating death toll of the pandemic. The research suggests many of those who will die because of new cancers will also have an underlying medical condition. He said anyone with a health concern must be encouraged to see a doctor despite Covid-19 anxieties.
"Of those predicted to die, eight in 10 would have underlying health conditions," Prof Lawler said.
"People who suspect they may have cancer are worried about attending the doctor for two reasons. One, they don't want to put pressure on them because they feel doctors are overwhelmed by Covid-19.
"The other reason is that they are worried they might get Covid-19 by attending a health service."
The Department of Health's chief medical officer Tony Holohan has repeatedly urged the public to attend their doctor if they have concerns about other ailments. These numbers have increased somewhat in recent weeks but are still considered too low.
HSE figures show referrals of people with suspected cancers dropped significantly following the introduction of Covid-19 restrictions.
Referrals for suspected cases of skin cancer this year dropped by more than 70pc between March 16 and April 19 when compared with the number of cases in the period to mid-March. Lung cancer referrals dropped by 61pc, and the number of people being transferred for breast cancer checks dropped by 55pc. The number of prostate cancer referrals halved in this period.
"The message is, from a patient point of view and anyone who suspects they have cancer, please access your GP," Prof Lawler said.
"From a Government and assistance point of view, if we are encouraging people to access services, we need to make sure they are always there so people can be correctly diagnosed and put on the right treatment."
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