EXPERTS have warned that it is too soon to "let our guard fall" despite a mysterious fall in cancer deaths. 

The trend in Scotland defies warnings from organisations including the World Health Organisation that the pandemic had been "catastrophic" for cancer. 

A "deadly interplay" of delayed diagnoses and healthcare disruption would see deaths from colorectal and breast cancer alone spike by 15 per cent and 9% respectively in the UK over the next five years, according to the WHO's regional director for Europe, Dr Hans Kluge, speaking n February 2021.

And yet, as we approach the end of 2022, there is something puzzling in Scotland’s excess death statistics. 

Since the beginning of the year, the total number of cancer deaths registered with National Records of Scotland has been lower than the pre-pandemic average.

Not much lower - only 70 fewer, up to mid-November, than would normally be expected - but unusual at a time when overall mortality has shot up. 

READ MORE: Health inequalities in Scotland to blame for nearly 5000 extra cancer cases a year 

There are signals of a potential shift - between May 2 and November 13, cancer deaths in Scotland were 0.2% above the five-year average, compared to 1.6% below from January to May 1 - but the figures still sit in sharp contrast to the wider picture. 

From May to mid-November, there were a total of 2,878 excess deaths from all causes in Scotland.

To put that into context, it means that the number of people dying has been nearly 10% higher when compared to the average for 2016-2019 and 2021 combined. 

Broken down, the figure includes 714 excess deaths from circulatory causes - such as blood clots, brain haemorrhages and heart attacks - up 9.4% on the five-year average; 153 extra deaths from Alzheimer's and dementia (up 5.1%); and 1,450 excess deaths from "other" causes, a catch-all which does not include Covid or other respiratory ailments, but could cover anything from sepsis to suicide.

Notably, "other" deaths are up by nearly 21%. 

In comparison, there were just 16 extra cancer deaths. 

The question is, what is really behind this surprising trend - and will it last? 

"The thing about cancer is that it takes longer for most cancers to develop, so you can't really look at the numbers on excess deaths and say 'okay, there hasn't been an impact'" said Jonine Figueroa, a professor of molecular epidemiology and global cancer prevention at Edinburgh University who contributed to the Covid and Cancer Global Modelling Consortium during the pandemic. 

"Where a lot of the community is focusing efforts on is the incidence, because we know that there's been a lack of participation in early detection programmes and also a reduced capacity in healthcare systems. 

"What the cancer research community is concerned about is that continuing, which could have more downstream mortality consequences, but you'll probably not see this for another five years."

Figueroa added that the dip in cancer diagnoses seen during 2020 would be partly down to the pause in routine screening, but that the many of the cases normally detected through these programmes are at an earlier stage and "extremely treatable" - meaning that, even with delays which may have resulted in a poorer long-term prognosis, these patients are still likely to be alive.

This is especially true given the advances in cancer treatment over the past 10 years. 

"Just because you don't have a curative treatment for your cancer doesn't mean you will quickly die of cancer," said Dr Judith Anderson, a clinical radiologist and representative of the Royal College of Radiologists (RCR) in Scotland. 

"What we're much better at is keeping people alive, and there's been a significant increase in patients being treated for cancer who in the past might have been too old or unfit for treatment. 

"A lot of the current aims of cancer treatment - immunotherapy in particular - is how you keep people alive for longer with cancer."

Breast, bowel and cervical screening also makes up a comparatively small proportion of total cancer diagnoses each year in Scotland - around 7% - meaning that the overall impact of the pause may be comparatively small. 

READ MORE: 'Diagnosis was the trickiest part - after that it went like clockwork'

Another possibility is that the screening pause may have inadvertently benefitted more advanced or symptomatic cancer patients by alleviating pressure on diagnostic pathways.

If fewer people than normal were being referred for tests and scans in 2020, but those who were were being seen and treated faster, then we could now be seeing a small net gain in 2022 in terms of survival. 

"It's an interesting interpretation - I don't think we have the data to support that yet, but it's true that it was definitely more symptomatic patients coming through," said Figueroa, adding that the lessons of the pandemic could spur a re-evaluation of screening. 

She said: "I'm very keen on prevention and early detection, because it's cost saving but also life saving.

"But for something like breast cancer, where there's a lot of controversy about screening, maybe one of the benefits is we'll be able to do it smarter."

HeraldScotland: Professor Jonine FigueroaProfessor Jonine Figueroa (Image: Edinburgh University)

She added that the current data might also reflect an NHS which succeeded in prioritising urgent cancer care at the height of Covid - but stressed that it was too soon to "let our guard fall".

"We're not out of the woods yet. There's still a lot of backlog, changes in behaviour, and potential iniquities that might be accumulating. 

"The other thing we don't know for sure is this competing risk issue: a lot of the same risk factors for cancer patients are the same things that kill Covid patients, so have we just replaced cancer with a different disease?"

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It is a theory that Alastair Munro, a professor of radiation oncology at Dundee University, finds compelling. 

"Cancer is a disease of ageing populations - there is a school of thought that if everybody lived to 200 everybody would get cancer," said Munro, a consultant oncologist whose research includes mathematical modelling of oncology. 

"If somebody is in their 70s and they've died of Covid then they're not going to die in their late 70s or early 80s diagnosed with cancer and put a strain on the service.

"It's a terrible thought that by rampaging through that older population Covid may have decreased longer term pressures on cancer services."

He added that it is possible that the over-70s who survived the pandemic are fitter than average.  

"Covid-related deaths killed off the more vulnerable of the elderly, which means the elderly who survived are less vulnerable.

"So on the basis that the fitter you are the better your outcomes if you develop cancer, it may be that in the longer term survival rates for treated cancers go up because of that phenomenon.

"That's purely speculative though."

HeraldScotland: Covid had a disproportionate effect on the most elderly and vulnerableCovid had a disproportionate effect on the most elderly and vulnerable (Image: PA)

However, Munro added that spiralling waiting times for tests and scans in 2022 could mean that people "die waiting" before they are even diagnosed - particularly from very aggressive forms of the disease, such as lung cancer. 

"If people are never diagnosed with cancer, they can't count as a cancer death," he said. 

Another puzzle is the apparent discrepancy between Scotland and England, where official figures recently indicated that there have been 900 excess cancer deaths since the beginning of September. 

In fact, the two countries simply count the deaths differently.

Scotland tallies excess deaths based on what is listed as the "underlying cause of death" on a death certificate. Although several ailments can be mentioned as contributory factors, only one is the underlying cause. 

In England, excess deaths are counted based on the underlying cause and contributory factors. 

"In Scotland, you either die of Covid or you die of cancer, but you can't have both," said Munro.

"But if you die of Covid in England with a little bit of cancer, you get counted as a cancer death and a Covid death.

"I think the Scottish figures are low because of the counting method."

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Overall, however, he suspects that depictions of a looming "cancer timebomb" are probably overblown. 

He said: "I think what we will see is a gradual drift up in the excess cancer deaths over the next year or so, and then a gradual decline thereafter. 

"What I don't feel we'll see is a sudden short-lived post-pandemic epidemic of cancer deaths."

Those on the frontline, however, describe a healthcare system on the brink.

In this scenario, people developing cancer in 2022 are coming up against an NHS much less able to cope with demand than that of 2020.

The number of cancer patients referred for tests and treatment between April and June this year was 33% higher than in the same period during 2020 - 4,072 versus 3,056 - while the number of people on waiting lists for key diagnostic tests has soared from 84,500 in March 2020 to 160,000 by the end of September this year. 

Among them were 33,000 people who had been waiting over six months for radiology tests such as CT scans and MRI, and 4,700 who had been waiting over a year for endoscopy. 

HeraldScotland: No one referred for a key diagnostic test should wait longer than six weeks, but urgent cancer referrals are supposed to be completed within two weeksNo one referred for a key diagnostic test should wait longer than six weeks, but urgent cancer referrals are supposed to be completed within two weeks (Image: PA)

Patients with an "urgent suspicion of cancer" are prioritised. Their tests are supposed to be carried out within two weeks, compared to the overall target turnaround time of six weeks. 

However, Dr Anderson - a radiologist based at the Royal Infirmary of Edinburgh - said sheer length of waits now facing the "routine" (non-cancer suspected) patients is leading some doctors to escalate more cases to urgent, with knock-on effects for diagnosis. 

She said: "We're always trying to prioritise our urgent suspicion of cancer patients, who should all be scanned and reported within two weeks of the first request. 

"You move heaven and earth to get that done. 

"But because that group of patients is increasing, it means the routine outpatient waiting lists are getting significantly longer week after week. 

"Where I work, the radiographer in charge told me the waiting list for routine outpatients is increasing by one week every two weeks right now. At the moment we're at 15 weeks; soon we'll be at 16.

"The trouble then is that clinicians start requesting scans as 'urgent' because they might think the patient could wait six weeks - but they don't think they could wait 16 weeks. 

"That squeezes the system and there are places now - especially in the cancer centres - where it's becoming very difficult to meet that two-week [cancer] target."

HeraldScotland: The number of people waiting for a key diagnostic test is up, but the number being seen within six weeks is much lower than it was pre-pandemicThe number of people waiting for a key diagnostic test is up, but the number being seen within six weeks is much lower than it was pre-pandemic (Image: PHS)

READ MORE: Scotland's radiologist shortfall 'set to hit 30 per cent by 2026'

Anderson stressed that even the routine referrals will include some unexpected cancer cases who, as result of scanning delays, will be diagnosed at a later stage "with a lower chance of a cure or treatment". 

This is already being seen in A&E departments, she added. 

"Every day we're seeing people come to the front door often with advanced cancer that's not been picked up earlier.

"That shouldn't be happening in a modern healthcare system."