A London-based surgeon has warned of a big backlog in cancer diagnoses following an investigation into the wider impact of the pandemic on the health service.
Figures obtained by the BBC's Spotlight revealed a massive fall in the number of people in Northern Ireland with suspected cancer being referred to consultants in the months of lockdown.
There were 7,500 fewer so-called red flag referrals in April and May - half the figure compared to the same period last year. The programme reported the figure as the equivalent of every adult and child in a town the size of Donaghadee being suspected of having cancer but not having it checked by a consultant.
In January to February this year an average of 2,227 referrals a week were recorded, dropping to 1,000 by the week beginning March 16, according to the Health and Social Care Board. This had dropped to 700 a week by mid April.
Head and mouth surgeon Luke Cascarini told the programme: "Where are all the patients that we would have been treating if we hadn't been treating Covid?" He added: "I don't think there's any reason to think that the incidence of cancer has dropped over the last few months.
"So, I think there's a big backlog and I think, like a lot of doctors, we're beginning to feel extremely proud of everything that's been done to cope with the crisis.
"I think we now need to deal with those undiagnosed or untreated cancers."
Spotlight's investigation has also revealed that in April there were around 600 more deaths registered in Northern Ireland than would be normal for the time of year.
Most of those excess deaths, as they are known, were caused by coronavirus. But about 40% - over 200 of the excess deaths - were not linked to coronavirus.
During that first full month of lockdown, more than 70 people under the age of 45 died - an increase of almost 60% from the same time last year.
Only four out of the 70 deaths were caused by the virus. Some excess deaths may be Covid-19 victims who have been overlooked.
But it is clear that there was also a surge in deaths during lockdown for causes that have not yet been explained.
Spotlight is available on BBC iPlayer.