The COVID-19 pandemic will likely cause thousands of excess deaths from colorectal cancer in Australia unless catch up screening programs are urgently instated, say experts.

Modelling done by the COVID-19 and Cancer Global Modelling Consortium working group predicted that disruption to screening and follow up colonoscopy for the diagnosis of colorectal cancer could lead to a 0.5-2.0% relative increase in deaths through to 2050, threatening to undermine decades of progress made in reducing bowel cancer mortality rates across the country.

Investigators including Professor Karen Canfell from the University of Sydney’s School of Public Health said urgent attention was required for Australia to avoid the substantial number of deaths predicated by the widespread shutdown of routine colonoscopy.

In a study in Lancet Gastroenterology and Hepatology the multinational group estimated that without catch up screening, disruption to screening programs of three months would result in 1672 additional diagnoses and 979 additional deaths.

For disruption of six and 12 months there would be 3552 additional diagnoses and 1961 additional deaths or 7140 additional diagnoses and 3968 additional deaths up to 2050, respectively.

Already happening

And as clinical services in Australia resume, signals hinting towards that scenario were already starting to unfold, clinicians told the limbic.

Colorectal surgeon Associate Professor Graham Newstead of the University of NSW said he was already seeing devastating impacts of the disruption to colonoscopy services play out as a result of the halt to elective procedures at the start of pandemic.

“There’s a big difference between waiting a long time to get your varicose veins done and waiting for something which will kill you,” he said in an interview.

 “We’ve already seen in our own hospital several patients just recently – there are two patients I’m already aware of – who have been on the waiting list for colonoscopy after a positive [FIT]. They’ve had no symptoms and have gone longer than 120 days [from positive FIT to colonoscopy] and both have just been diagnosed with advanced tumours.”

“There’s no doubt in the science, which shows that [in] 120 days you start moving stages of cancer: people who might have been a stage A or a stage B become stage C or a D. And so we are not curing people by doing a colonoscopy when they’ve got advanced cancer.”

The real problem, Professor Newstead says, is that pre-COVID colonoscopy waiting lists were already ‘unacceptably’ long in the public setting, with many people going beyond the recommended 30 days to colonoscopy after a positive FOBT.

While acknowledging the demand for colonoscopy was rising following the transition from government funded five-yearly FOBT screening to two yearly, Professor Newstead said it was a move that had driven down bowel cancer mortality rates.

“We can show that with FIT there has been a definite shift of the curve from late stage cancers presenting with bowel obstructions and liver secondaries to early find cancers which are cured by surgery. There’s no doubt that two-yearly screening is good –  but it’s not much good if you do the test and then you don’t scope people when they get a positive.” 

Excess deaths

Bowel Cancer Australia CEO, Julien Wiggins, shared similar concerns about a worrying number of excess bowel cancer deaths in the months and years ahead.

He told the limbic that 216,00 fewer screening kits had been returned from Jan-Sept last year compared to the same period in 2019. He also noted that 78,000 fewer colonoscopies and sigmoidoscopes had been carried out and 400 fewer bowel cancer surgeries performed across the country in 2020 compared to 2019.

“The real impacts of the pandemic are profound and yet to be fully felt by the system. I think the real tsunami is coming in terms of how many patients need to have a test kit returned and need to have colonoscopy,” he said.

In their paper, investigators from the Modelling Consortium Working Group said the projections presented a clear argument for the health benefits of catch-up screening programs.

With immediate catch-up screening, the impact of such disruption would be minimised to a relative increase in excess deaths of 0·1% compared to as much as 2% with no catch up, they estimated.

But the Group conceded that such programs might temporarily increase colonoscopy demand to nearly twice that of normal levels, which might exceed the capacity of health systems.

FIT cut-off levels

One way to mitigate this, they said, could be to introduce higher FIT cutoff values at screening during the recovery period to prioritise people who were at increased risk.

But Professor Newstead cautioned against the strategy.

“The [FIT] is in no way a perfect test – it misses 85% of polyps less than one centimetre in diameter because they’re not bleeding. Already it is not sufficiently sensitive and so the worst thing we could do is make therm more specific so that they don’t pick up the haemorrhoids; then we definitely won’t pick up the the bigger polyps or even the occasional cancer. We want anybody with a positive; we don’t want more specificity because we’ll miss cases. I know we’re doing colonoscopy on people that end up just having haemorrhoids but we’ve got to do them.”

Julien Wiggins agreed that catch up screening was the key to avoiding excess bowel cancer deaths but also warned against raising screening test cut-off levels.

“I’m cautious on that approach. Let’s deal with the leavers we can control at this point – the cut off potentially misses cases the higher we make it and I feel if we really want to ensure that we’ve got a very robust system I wouldn’t want, at this point, to be tampering with cut-offs to the test kit sensitivity. I think it’s paramount that we keep it as it. Our data has already been built around that sensitivity so let’s get the resources all working together synchronised such that we’ve got that common denominator of the same cut-off level, let’s keep the consistency there.”

Public vs private

Whether the country had the capacity to cope with the onslaught of colonoscopy procedures would depend on public and private hospital services coming together to pool resources he said.

“There have been solutions in the past whereby, if you are on a waitlist in the public sector for longer than a defined period, then you are tipped over into the private setting to ensure that the colonoscopy is done. It’s time to come together again even if it’s just for the catch up. We need to reset the system so we can be back to pre-pandemic levels at least – and I hasten to add that the waitlist times were already unacceptable pre-pandemic but creative solutions can and have been done in the past. I think it’s incumbent upon us now to actually look for a way forward to play catch up because ultimately we don’t want to have patient outcomes impacted detrimentally going forward and we know we can do it, we know we can arrest those numbers in the modelling. It’s there if we do it and act on it quickly.”

Professor Newstead, who is also Head of the Colorectal Unit at the Prince of Wales Private Hospital, echoed a similar sentiment. He said there was potential to increase productivity in the public setting to meet higher colonoscopy procedure rates carried out in private hospitals.

“I know in our hospital, and in many hospitals, on average we can get through a patient every half hour in the private setting – it’s not rushed, I pride myself on being careful and detailed – we’re not rushed at all. In the public they won’t let you book them in like that.

“There’s a lot more we used to do in the public before we even had private colonoscopy – we were getting through twice the amount of work in the public we would get through today.”

Recalling agreements made between many public and private hospitals to pool resources during the height of the pandemic – in co-located hospitals public ICU wards were reserved for COVID patients and private ICUs reserved for non-COVID cases – Professor Newstead questioned why the systems could not work together again.

“Why can’t we do the same thing in reverse? If they’ve got a big overflow in the public hospitals for these terrible, but preventable, problems why can’t we do more public lists in the private hospital?”