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New paper casts doubt on trusted Canadian breast cancer screening guidelines – National Post

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Co-authors question findings of seminal study, say women aged 40 or older should be given mammograms if they want them

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A new paper published this week in the Journal of Medical Screening suggests a Canadian study used to form breast screening guidelines around the world for decades is flawed.

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The authors of the paper — co-written by researchers at Sunnybrook Research Institute in Toronto, The Ottawa Hospital, the University of British Columbia, the University of Alberta and Harvard Medical School — take issue with the randomized trials used to determine whether mammograms and breast exams helped save women’s lives, saying they were not randomized at all.

The Canadian National Breast Screening Study (CNBSS) started with two breast screen trials in 1980, and eventually involved tens of thousands of women in 15 Canadian urban centres. Investigators concluded that an annual mammogram for women aged 40 to 49 who are at average risk of breast cancer does not reduce the mortality rate any more than a physical exam.

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A control group of women aged 40 to 49 received an initial physical exam, then nothing further. The other group received up to five annual mammograms and physical exams. By the end of the study, 38 women in the mammography group had died of breast cancer, compared to 28 women in the control group.

As a result, Canadian researchers concluded that annual screening in women aged 40 to 49 at average risk does not reduce breast cancer mortality any more than a physical exam. Their findings were the basis for guidelines around the world that do not recommend annual screenings for women in that age group, including the most recent set put forth by the Canadian Task Force on Preventive Health Care.

I did not expect to find such clear, clear evidence of what was going on.

The risk of false positives and over-diagnosis is cited as a key issue in earlier screening. In such cases, even benign lumps would require a biopsy. Experts argue that radiation, chemotherapy or surgical treatment of breast cancer can be harmful, and that must be considered in treating a patient who might not even have it.

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Despite that, the authors of the new paper say women aged 40 or older should be given mammograms if they want them because there are several problems in the findings of the CNBSS.

Dr. Jean Seely, co-author of the new paper and a professor of radiology at the University of Ottawa and head of breast imaging at The Ottawa Hospital, told CBC News there is “conclusive confirmation” the study was conducted with women — particularly in some locations — who were not randomly assigned.

She said when the authors of the paper interviewed 28 staff members who worked on the original study, some confirmed there were multiple instances in which women with detectable lumps, who were pre-screened by a nurse, were deliberately placed in the mammography group.

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“I was astonished. I did not expect to find such clear, clear evidence of what was going on,” Seely told CBC News. “Then I think my next reaction was anger. How could this have been allowed?”

Debate has swirled around the studies since the results of the CNBSS were published. Critics have questioned the inclusion of women with advanced cancers, the quality of the screening participants received, and the factors used to determine whether mammograms were beneficial for women in their 40s. Experts have also voiced doubt about the randomization, though an investigation conducted by external experts failed to find “credible evidence” that it was subverted. Those investigators further said that if there were acts of subversion, they were few and their impact on the study’s findings trivial.

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The authors of the paper published in the Journal of Medical Screening disagree, saying just seven cases of women with lumps removed from the mammography group would have skewed the results.

Seely hopes the evidence she and her co-authors presented in their paper lead to change.

“I think probably the most personal challenging moments that I have in my practice are when I see a woman in her 40s who presents with an advanced breast cancer,” she told CBC News. Most often, the patient was told by a family doctor that she didn’t need to be screened because of her age.

“On a personal level, as a professional, I find this very, very difficult,” Seely told CBC News.

Women aged 50 and older have higher rates of breast cancer diagnosis, according to the Canadian Cancer Society, but women between 30 and 49 with breast cancer are more likely to die from it. They represent 17 per cent of all cancer deaths in Canada, compared to eight per cent of women aged 50 to 69.

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Despite the findings published in the new paper, the CNBSS has its champions, including the study’s principal investigators.

The study’s lead, Dr. Anthony Miller, a professor emeritus at the Dalla Lana School of Public Health at the University of Toronto, told CBC News, “We had a great deal of understanding of what could go wrong with randomization and we took a great deal of care to ensure it didn’t apply in the National Breast Screening Study.”

Miller told CBC News extensive quality-control measures maintained the integrity of the study, and he denies the possibility that any women were not placed randomly within the trials.

Seely and her co-authors have brought their concerns about the CNBSS to the University of Toronto and the Canadian Medical Association Journal, both of which were involved in the original study.

In a statement, the university’s office in charge of research, oversight and compliance said it is reviewing their concerns, and “places a high value on research integrity.”

The university did not specify details or a timeline of its review.

In her own statement to CBC News, Dr. Kirsten Patrick, interim editor-in-chief of CMAJ, said the journal “will co-operate with the university office’s process fully and will await the office’s report on the outcome of the review before deciding if any further action is needed.”

She did not provide any further comment.

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DeMille Anticipates Broader Rollout Of 4th Dose Vaccination – Country 105

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The Thunder Bay District Health Unit (TBDHU) is getting ready for the annual flu shot campaign, as well as a broader ask for arms to get the fourth dose of a COVID-19 vaccine.

The province expanded the second booster dose eligibility on April 7th to those who are 60 and over as well as First Nation, Inuit and Métis individuals and their non-Indigenous household members aged 18 and over.

“At this time, I’m not hearing any indication of the province opening up (eligibility) to the broader population, and I’m not sure really we would have evidence that would be needed at this time,” DeMille told Acadia News Monday. “We are much lower in terms of the amount of COVID-19 (cases) in the province of Ontario. With the summertime, we see overall less spread (of the virus).”

DeMille did mention that the District anticipates the call will get broader in the fall.

As of June 21st, 133,334 people within the TBDHU have received one dose of a COVID-19 vaccine and 80,719 have received three doses.

Officials have given fourth doses to 18,687 individuals as of the last update.

DeMille was also asked about a return to school in September, and what that might look like after Canada’s Chief Public Health Officer Dr. Theresa Tam told Federal MPs on June 8th that there is a real threat of the seventh wave of COVID-19.

The Medical Officer says it’s hard to look into the crystal ball and pinpoint what will happen based on the fact that right now a majority of the new infections are the Omicron variant.

“The schools overall did fairly well,” DeMille stated. “We know that a lot of people did get infected, which can cause a lot of disruption because people still need to isolate so that they are not spreading (the virus) to others. Likely a lot of spread happened in the schools when we re-opened in January and through the last few waves.”

DeMille noted that the schools took a lot of measures that helped in previous waves, including improving ventilation.

“I anticipate that (masking) will always be optional, but when the Omicron variant is spreading, it’s always helpful when people are masking in indoor spaces when they are interacting with others,” said DeMille. “(Down the road) we might recommend that people wear masks in schools, but that advice will really depend on what we see circulating, how much it is circulating and what the impact is on schools.”

DeMille mentioned whether it is the school, the workplace, or any other indoor space, the goal is to return to as normal as possible in an eventual post-pandemic world.

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Monkeypox is not yet a global health emergency, says WHO – Global News

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Monkeypox is not yet a global health emergency, the World Health Organization (WHO) ruled on Saturday, although WHO Director-General Tedros Adhanom Ghebreyesus said he was deeply concerned about the outbreak.

“I am deeply concerned about the monkeypox outbreak, this is clearly an evolving health threat that my colleagues and I in the WHO Secretariat are following extremely closely,” Tedros said.

The “global emergency” label currently only applies to the coronavirus pandemic and ongoing efforts to eradicate polio, and the U.N. agency has stepped back from applying it to the monkeypox outbreak after advice from a meeting of international experts.

Read more:

Canada signs $32.9M contract for smallpox drug with manufacturer Chimerix

There have been more than 3,200 confirmed cases of monkeypox and one death reported in the last six weeks from 48 countries where it does not usually spread, according to WHO.

So far this year almost 1,500 cases and 70 deaths in central Africa, where the disease is more common, have also been reported, chiefly in the Democratic Republic of Congo.

Monkeypox, a viral illness causing flu-like symptoms and skin lesions, has been spreading largely in men who have sex with men outside the countries where it is endemic.

It has two clades – the West African strain, which is believed to have a fatality rate of around 1% and which is the strain spreading in Europe and elsewhere, and the Congo Basin strain, which has a fatality rate closer to 10%, according to WHO.


Click to play video: 'More than half of Canadians confident in monkeypox response, but 55% worried about spread: poll'



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More than half of Canadians confident in monkeypox response, but 55% worried about spread: poll


More than half of Canadians confident in monkeypox response, but 55% worried about spread: poll – Jun 17, 2022

There are vaccines and treatments available for monkeypox, although they are in limited supply.

The WHO decision is likely to be met with some criticism from global health experts, who said ahead of the meeting that the outbreak met the criteria to be called an emergency.

However, others pointed out that the WHO is in a difficult position after COVID-19. Its January 2020 declaration that the new coronavirus represented a public health emergency was largely ignored by many governments until around six weeks later, when the agency used the word “pandemic” and countries took action.

(Reporting by Jennifer Rigby; additional reporting by Mrinmay Dey; Editing by Sandra Maler)

© 2022 Reuters

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Kingston, Ont., area health officials examining future of local vaccination efforts – Global News

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More than 455,000 people in the Kingston region have been vaccinated against COVID-19.

Now health officials say they’re using the summer months, with low infection rates, to look ahead to what fall might bring, urging those who are still eligible to get vaccinated do so.

Read more:

Kingston Health Sciences Centre to decommission COVID-19 field site

“Large, mass immunization clinics, mobile clinics, drive-thru clinics and small primary care clinics doing their own vaccine,” said Brian Larkin with KFL&A Public Health.

Infectious disease expert Dr. Gerald Evans says those who are still eligible for a third and fourth dose should take advantage and roll up their sleeves during the low-infection summer months.

“Now in 2022, although you still might get COVID, you’re probably not going to be very sick. You are less likely to transmit and ultimately that’s one of the ways we’re going to control the pandemic,” added Evans.

He expects another wave of COVID-19 to hit in late October to early November and that a booster may be made available for those younger than 60 who still aren’t eligible for a fourth dose.

Read more:

Kingston, Ont. COVID assessment centre cuts hours for the summer

“The best case scenario is a few more years of watching rises in cases, getting boosters to control things and ultimately getting out of it with this being just another coronavirus that just tends to cause a respiratory infection and worst-case scenario is a new variant where all the potential possibilities exist to have a big surge in cases and hopefully not a lot more serious illness,” said Evans.

Public Health says they’re still waiting for direction from the province on what’s to come this fall.

“We’re expecting that we would see more age groups and younger age groups be eligible for more doses or boosters but about when those ages start, we have yet to have that confirmed,” said Larkin.

The last 18 months of vaccines paving the way for the new normal could mean a yearly COVID booster alongside the annual flu shot.

© 2022 Global News, a division of Corus Entertainment Inc.

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