Concerns about the 2024 draft breast screening guidelines.
On May 30, 2024, The Canadian Task Force on Preventive Health Care (Task Force) released its draft breast cancer screening guidelines. Dense Breasts Canada is deeply concerned that the guideline update process lacked accountability, transparency, scientific rigour, equity, objectivity, and credibility. These guidelines are simply dangerous and need to be revised. We recommend the Task Force be disbanded and rebuilt.
The concerns below were brought to the attention of Minister Mark Holland, senior officials in Minister Holland's office and the leadership of the Public Health Agency of Canada over the past years. The Minister on May 30th held a press conference and expressed his concern and disappointment. He outlined a plan to review the processes, membership and evidence. Here is his statement.
We hope to see the government take accountability and ensure the safety of Canadians. Canadians deserve guidelines based on current science and that recognize our diverse population.
Please read our concerns and submissions below.
Please consider adding your voice by emailing Minister Holland
The Task Force that creates the breast screening guidelines, as well as many other guidelines, is an independent body, made up of volunteers who do not have any expertise in breast cancer. The Task Force is funded by the Public Health Agency of Canada.
Role of the Task Force: It develops guidelines to support~48,000 family doctors and 6000 nurse practitioners in delivering preventive health care to Canadians. However, when it comes to breast cancer screening guidelines, we have many concerns. Many other specialties do as well. A coalition has been formed with these specialties. Coalition of Responsible Healthcare Guidelines responsiblehealthcareguidelines.ca
The 2024 breast cancer screening recommendations are essentially unchanged from 2011 and 2018. The guidelines given to 48 000 family doctors and 6000 nurse practitioners:
- Recommend AGAINST screening at 40
- Recommend AGAINST supplemental screening for women with dense breasts
- Recommend AGAINST screening after 74
- Recommend screening only every 2-3 years for ages 50-74
These guidelines are causing harm to Canadians. We need to see change.
In May 2023, the US Task Force published draft guidelines, recommending that the screening age be lowered to 40. The Canadian government announced $500,000 to expedite an update of our breast cancer screening guidelines (June 2023).
The announcement stated, ?Having breast cancer screening guidelines that are based on the latest science is essential?. Updates to Task Force guidelines ensure they remain reflective of the best and most current available evidence."
Members of the Liberal government stated that it was important to ensure that women have access to screening at 40 because more women are being diagnosed earlier and because the needs of racialized women are not being taken into consideration.
Rebuild the Task Force with fulsome input from experts in breast cancer screening and other areas of health.
The 12-member volunteer panel does not have any experts in breast cancer or breast imaging.
The 5-member breast working group includes two family doctors, a gastroenterologist, a nephrologist, and a nurse practitioner.
These non-breast cancer experts decide and vote on the guidelines. .
There are only two patients involved in the 2024 update, and they do not vote.
Breast cancer experts, who are aware of the clinical context and changing data, should have a vote, but they are excluded from voting/decision-making.
Many Canadians assume that the guidelines are made by breast cancer experts. This is a breach of the public?s trust.
There are many errors discussed below as a result of expert input not being heeded.
Rebuild the Task Force with accountability.
The Task Force lacks accountability. It was formed in the 1970s, but disbanded in 2005. When it was resurrected in 2010, the design failed to include an internal accountability structure for oversight.
The Task Force is considered to be an arm?s length body and that while this is reasonable from a scientific point of view, accountability is needed. This is critical in ensuring that guideline errors are acknowledged and corrected in a timely fashion and that expert advice is not ignored.
The conduct of the Task Force, in terms of how members are appointed, how working groups are composed, how evidence is selected, how recommendations are made etc. requires a governance structure that makes it accountable to Canadians.
Once the guidelines are published, they remain in place ~7 years. There needs to be a process for updating the recommendations earlier as new research is published, so that they reflect current knowledge and clinical realities.
The Task Force does not monitor the outcomes of their guidelines. There have been worsening outcomes with an increase in the incidence of later-stage breast cancer since 2011 following the recommendation not to routinely screen women in the 40s.
A validated Canadian model predicts that following the Task Force recommendation of not screening Canadian women in their 40s is leading to over 460 avoidable breast cancer deaths in Canadian women each year. Recently published Canadian research also shows that there are large reductions in treatment costs when cancers are detected earlier.
Multiple other screening guidelines in cancer and non-cancer fields have similar reactions from experts and are similarly concerning. The problem is fundamental to the structure and the accountability of the Task Force.
The Public Health Agency of Canada (PHAC) was notified by physicians who testified of egregious behaviours by the Task Force leadership; yet, there were inadequate mechanisms to address these actions.
Expert advisors to the Ottawa Evidence Review Synthesis Centre (ERSC), conveyed that their expert input was put aside and that the Task Force dictated to them what evidence to consider. ?The working group overrode our recommendations ...they dictated what evidence could be used. They insisted on including the Randomized Controlled Trials (RCTs) that were 40 to 60 years old. Because of that, the evidence generated for these recommendations does not reflect the most up-to-date evidence.? Since the Task Force insisted on the inclusion of now obsolete data from RCTs that did not reflect technology, treatment or outcomes of breast cancer management today, these old trials misinformed the current breast screening guideline update.
The recommendation not to screen at 40 stands in stark contrast to the recommendations from the U.S. Task Force, the Canadian Cancer Society, NCCN, US breast cancer organizations, the Canadian Society of Breast Imaging, CAR, and the majority of Canadian provinces, all of which have recognized the need to screen at 40.
Rebuild the Task Force with full and appropriate transparency.
Expert advisors were required to sign nondisclosure agreements and irrevocably be signatories to the recommendations made by the Task Force, notwithstanding that their expert input may have been ignored or that they disagreed with the recommendations.
There was siloing of information due to the use of multiple evidence review centres in the guideline making process; each evidence review centre was unaware of the others? work.
Task Force members promoted the inclusion of patient voices in the guideline creation process, however, the two patients had inadequate training and no vote on recommendations.
The Task Force released the draft guidelines but did not reveal or release all evidence to support their conclusions. The modelling results are not yet published.
It was not explained to the public that the Task Force used the US Task Force breast density evidence review and did not do their own evidence review in creating the guideline on supplemental screening for women with dense breasts.
The Task Force will not explain why figures for over diagnosis and the number of breast cancer cases differ significantly from the numbers in the 2018 guidelines.
Rebuild the Task Force with content expert leadership and methodologist assistance.
Content experts were members of the Working Group but they were not allowed to vote on the resolutions.
Task Force members lack the necessary expertise to evaluate the significance of evidence, the validity of data, and the most suitable analytical methods concerning the current diagnosis and treatment of relevant diseases. It is important to move beyond RCTs as the US Task Force has done, ?Randomized trials include technology that is no longer representative of current practice. Observational trials allow us to be more quantitative and to use modern data to show what the possibility of mortality reduction is. Modelling will allow us to go beyond that and extrapolate from what we've learned in the randomized and observational studies.
There is a great deal of evidence on the benefits of supplemental screening for women with dense breasts and starting screening at age 40; yet, as non-experts, Task Force members diminished the value of this evidence.
Task Force ?set arbitrary thresholds to assess the data and used too short an observation time to allow the full impact of the benefits to be measured. The absence of meaningful involvement by content experts resulted in errors in interpretation of data and misplaced emphasis on the weight of short-term (10-year) survival while ignoring long term survival benefit of early detection. Ten years is an inappropriate timeline to determine the benefits of early detection given the long trajectory of breast cancer where risk of recurrence continues 20-30 years after diagnosis, underlying the need for inclusion of disease experts to understand the context of the disease they are studying.
The Task Force suggestion of a 3-year screening interval for women 40-74 is without solid basis in evidence.
The Task Force omitted the benefit of early-stage diagnosis and decreased morbidity of treatment. Specifically, in their knowledge translation tool, the only benefit of early detection they considered was the decreased risk of dying of breast cancer, but not the years of life gained (highly important for younger women) or the options of avoiding mastectomy, chemotherapy, and armpit surgery that often results in lifelong swelling of the hand and arm, which women consider as huge benefits. As such, they are communicating only half the benefit of screening, but all of the potential harms. Additionally, they assumed the mortality benefit was the same for women of all ages, despite evidence showing that women 40-49 have higher benefit.
The Task Force has a dangerous misconception that improved life expectancy is attributable to better treatment, implying that treatment is a substitute for early detection. This comes from a belief based on a lack of awareness of all the data and a strong belief that treatment can solve anything. The Task Force view is problematic.
Some members of the Task Force say that screening is less important because treatment is getting better, but it's not a contest. Screening and treatment are synergistic. Cancer can be treated more effectively and less aggressively when it's found earlier. The stage of diagnosis does matter. Some members of the Task Force claim that screening can't save the lives of women with rapidly growing cancers. That's not true. Statistics Canada has shown that when triple negative cancer is detected at stage one, the five-year survival is 96%, but at stage four, it's only 7%.
The Task Force uses an incorrect metric for early detection in their modelling: screen detected cancers are typically Stage I, therefore Stage II and beyond should be considered evidence of screening efficacy, while the Task Force uses Stage III and beyond.
A state of confusion exists for physicians and the public. The current state of multiple disparate guidelines on the same topic coming from specialty societies and the Task Force leaves family physicians and patients unsure of what screening regimen is optimal. Expertise from specialist groups should be incorporated into the guideline process so that there are clear national guidelines.
Task Force members must have the expertise to evaluate incoming evidence objectively, free from bias, ensuring that family doctors and the public receive impartial information to inform their health decisions.
Rebuild the Task Force with ethics oversight.
Oversight is required with respect to ethical conduct of the Task Force and Working Group members. During the 2023/2024 update, Task Force members made public statements voicing their opinions on screening and indicating a prejudicial stance on the recommendations, up to a year before the update process had been completed. They were not removed from influential leadership positions, despite attention being drawn to their statements. A predetermined outcome for the guidelines was evident. Before the Task Force even began its work on this guideline, the co-chair publicly stated that she didn't believe there was any new evidence and didn't think the recommendations would change.
There were strong indications of bias by Task Force members in terms of undervaluing the benefits and overstating the harms of screening.
Data is presented by the Task Force in a manner that is likely to misinform the public. Michelle Nadler, advisor to the Task Force, stated information to the public ?should be accessible and shared in absolute numbers.? However, the exclusive use of absolute numbers in Task Force documents and recommendations creates false perceptions. This non-standard practice tends to minimize the large benefits associated with earlier cancer detection. Data should be presented in both absolute and relative terms.
In 2018, the Task Force made egregious errors that have gone unchecked: They stated that there were only 7 cancers in 1000 women 40-49 in 7 years. However, in the 2024 guidelines, they state there are 19 cancers in 1000 women in 10 years. The number of cancers in women 40-49 can be derived from Statistics Canada incidence rates. By falsely stating there were fewer cancers in women 40-49 in 2018, the Task Force minimized the value of screening.
In the 2018 recommendations the Task Force ignored other data and chose to present a single inflated value of 48% for overdiagnosis (while more credible reports suggest 1-10%). This came from the Canadian National Breast Screening Study (CNBSS). The CNBSS is currently under investigation by the University of Toronto for subverted randomization. The CNBSS publication on overdiagnosis has been heavily criticized due to inconsistent data. Furthermore, the Task Force made major methodological errors in applying the overdiagnosis estimate.
The ERSC for the 2024 guidelines used multiple trials to arrive at an estimate of overdiagnosis. They found that overdiagnosis including the discredited CNBSS trial was 11% (DCIS and invasive cancers) and 6% (invasive only). Without the CNBSS, these numbers are 9% (DCIS and invasive) and 3% invasive. Again, the 2018 guidelines contained an error in the value for overdiagnosis which devalued screening, The Task Force continues to use the 11% value of overdiagnosis for the 2024 guidelines which includes the CNBSS trial.
The participants in the historical RCTs (such as the flawed CNBSS) were almost entirely white women. This ignores the important issues of earlier, more aggressive cancers and poorer outcomes in racialized women, failing to consider Canada?s diverse population and introducing inequity.
The Task Force acknowledged the increased risk of breast cancer in aged 40-49 racialized women and increased mortality, but did not lower the screening age to give these women equity in the opportunity for early detection.
The Task Force continues to use a static, ?one size fits all? tool which does not individualize a women?s risk to help inform her appropriately of her own personal benefit of screening. There are validated risk assessment tools, such as the IBIS tool, which could be incorporated into a personalized decision tool.
The Task Force used uneven and inconsistent thresholds of uncertain origin to create recommendations for screening. To elaborate (outside of testimony), there were 1350 cases of cervical cancer in Canadian women of all ages in one year, and 350 deaths. The Task Force recommends screening for cervical cancer. The incidence of colorectal cancer in ages 50-59 is ~ 50/100,000 and there is a clear recommendation to screen. However, the incidence of breast cancer in women 45-49 is 164/100,000 and yet there is no recommendation to screen.
Dr Nadler, advisor to the Task Force stated that ?the Task Force's mandate is that women be informed?. Whatever choice they make about screening? the Task Force doesn't mind so long as the woman is informed.? To make informed choices, accurate information is required. It is unethical for the Task Force to misinform the public and physicians by providing inaccurate and manipulated data as seen in examples above and below.
Measures to audit outcomes associated with the Task Force recommendations must be implemented.
Statistics Canada data showed that following the 2011 Task Force recommendations, there was a noted ~10% increase in metastatic breast cancer both in women 40-49 and 50-59. The Task Force does not monitor the outcomes of its guidelines after they are implemented. Additionally, provincial differences in screening practices should be employed to determine downstream impacts of cancer screening. Modelling data should also be used.
If you don't screen women in their forties in Canada, we estimate this translates into 400 to 600 women's lives lost per year.
The US monitored mortality trends after recommending against prostate cancer screening in 2012, and subsequently changed its prostate cancer screening recommendations in 2018. We have no similar monitoring ongoing in Canada.
Although cost was not considered by the Task Force, a recent Canadian study shows that potential saving of $460M for each cohort of women 40-74 by avoiding the need for expensive therapies used for late-stage disease.
There are inequities across the country; where a woman lives impacts her ability to find cancer early. Currently, 6 provinces and territories screen at 40 (NS NL NB PEI YT BC), with 2 more (ON SK) scheduled to start in the next 6 months. AB and NWT screen at 45. Only QC and MB have not yet committed. Supplemental screening for women with dense breasts is also dependent on where an individual lives.
Current science and research that should be used in creating the 2024 Breast Screening Guidelines
- The incidence rates of breast cancer in women under the age of 50 in Canada have increased significantly. In the past 34 years, incidence rates of breast cancer in the 20s has increased by 45.5%, in the 30s by 12.5%, and in the 40s by 9.1%. This explains the importance of breast cancer in women the 40s (17% of all breast cancers diagnosed) and similar increases observed in the USA was one reason for changing the guidelines to screen women in the 40s.
https://doi.org/10.1200/JCO.23.00348
- Women aged 40?49 in jurisdictions that do not include women in the 40s in screening programs have significantly higher proportions of stages 2, 3 and 4 breast cancer compared to their peers in jurisdictions where women are included in the screening program at 40. Women in their 40s have significantly higher proportions of stage 2 and 3 breast cancer compared with those in their 50s. There has been a 10.3% increase in stage 4 breast cancer since 2011 when the Task Force guidelines were changed to not include women in the 40s. https://www.mdpi.com/1718-7729/29/8/444
- Mammography screening programs for women ages 40-49 in Canada are associated with significantly higher 10-year net survival for women diagnosed with breast cancer. Women ages 40-49 living in provinces/territories that included women in the 40s in screening programs had a reduced breast cancer mortality and a higher net survival at 10 years compared to those living in provinces that only included women in programs starting at age 50. https://doi.org/10.1177/08465371241246422
- The treatment costs based on stage and molecular subtype of breast cancer have risen exponentially due to the rapidly evolving breast cancer treatment. The 2023 mean costs per patient for Stages 1, 3 and 4 (incurable) breast cancer are C$ 39,263, C$ 97,668 and C$ 370,398. Breast cancers detected by screening are on average stage 1 while cancers that are found with symptoms are diagnosed at stage 2, 3 or 4. https://doi.org/10.3390/curroncol30090571
- Using The OncoSim-Breast microsimulation model (Canadian Partnership Against Cancer) to simulate a cohort of 1.53 million Canadian women born in 1975 showed that compared to no screening, screening mammography is associated with an absolute mortality reduction of 4.6 (biennial 50?74), 5.9 (biennial 40?74) and 7.9 (annual 40?74) fewer deaths per 1000 women. The absolute rate of diagnosis of advanced cancers (Stage 2, 3 and 4) falls in favor of earlier stages as the number of lifetime screens increases. https://www.mdpi.com/1718-7729/30/11/686
- Using the OncoSim model, based on 2023 treatment standards, screening a cohort of women annually for breast cancer starting at age 40 to 74 saves the Canadian health care system $459.6M over these women?s lifetime with 3499 breast cancer deaths averted and 52367 life years gained. This translates into a savings of $1880 for every woman screened (Abstract 174) https://cslide.ctimeetingtech.com/breast24hybrid/attendee/confcal_1/presentation
- Women of race/ethnicity other than White have earlier peak age at diagnosis, higher proportions of breast cancer diagnosed under age 50, and a peak age of death younger than White.
(submitted manuscript, collaboration with Stats Canada)
- The provinces/territories have changed their policies and are not following the Task Force guidelines. The provinces/ territories currently including women in their screening programs starting at 40 include BC, NS, PEI, NL, NB, and YT, and those starting at age 45 are AB and NWT. There are public commitments to lower the age to 40 in SK (Jan 2025) and ON (Fall 2024). In Quebec, the INESSS is reviewing the evidence. Manitoba is the only remaining province.
- The Evidence review team for the Task Force shows that using modern studies and observational trials, screening mammography is associated with a 40-60% reduction in breast cancer mortality, compared with the 27% reduction seen in the 40?60-year-old randomized trials.
The Canadian Task Force is not including important evidence that was used by the US Task Force in their May 2023 update recommending the screening age be lowered to 40.
The US used rising incidence of breast cancer in women in the 40s of 0.4% per year to change their guideline, and Canada has a similar significant rising incidence of breast cancer in women in the 40s of 0.5% per year since 2000, but this evidence is not being used. Why not?
The US placed heavy emphasis on modelling. We need to ensure that the OncoSim cancer models are updated with respect to accuracy and relevance.
The 2024 draft recommendations were released before the results of computer modelling were available.
Since randomized trials are unlikely to be conducted due to ethical considerations, cost and the length of time required, it will be increasingly necessary to rely on high-quality simulations in conjunction with available empirical data to inform healthcare policies.
Experience with COVID has shown the value of computer models in efficiently and quickly extrapolating from available data to represent future situations.
Recent work on costing of breast cancer therapies showed that the values used within OncoSim were outdated. It is not clear that other parameters within the model are being similarly updated to reflect technological advances in treatment with improved outcomes.
QALYS need to be updated so that an accurate depiction of morbidity with late-stage diagnosis can be adequately captured.
The Task Force has relied on research performed almost exclusively on white women in Canada and Europe from the 1960s to the 1980s. These old, racially-biased trials were used, and decades of modern research studies were ignored in the current 2018 guideline.
By using the old research and downgrading the more recent studies, including those using modelling, the Task Force is systematically discriminating against women of colour, who were not included in the old trials. The Task Force ignores that women of colour get breast cancer younger than white women. Their peak of breast cancer is in their 40s, and their cancers are on average, more aggressive than cancers in white women, and they are more likely to die when they are not caught early.
To ensure appropriate representation of Canada?s diverse population, the panel reviewing the evidence and the research they use should represent Canada?s diverse population.
The 2023 US breast screening guideline addressed the varying peak incidences among ethnicities by recommending starting screening at age 40.They made a commitment to help reverse the negative impacts of systemic and structural racism, gender-based discrimination, and bias. Canada should do the same, given our similar racial disparities, and established peak incidence and worse outcomes of breast cancer in the 40s in Filipina, Indigenous, Black, Asian, and Hispanic ethnicities.
Provinces are aware of the flaws in the Task Force guidelines and many have chosen to ignore them. This has led to variability in screening policies across Canada, resulting in unequal access across the country. This goes against the Canada Health Act.
Although the current Task Force recommendation is against screening at 40, four provinces screen at 40, one at 45 and two recently announced plans to screen at 40 starting in 2024. Three others are exploring policy change.
BC and AB already offer supplemental screening for women with dense breasts, and Ontario just published recommendations to do so.
In 2018, the Task Force did not acknowledge the risks of dense breasts and ignored evidence to support the use of supplemental screening. Dense breasts increase the risk of breast cancer and make it harder to see cancer on a mammogram. Women with dense breasts are not average risk, and 43% of women over age 40 have dense breasts.
Women with dense breasts are more likely to have a delayed diagnosis, larger, more aggressive cancers, and a poorer prognosis. Evidence on the benefits of supplemental screening has existed for decades.
The evidence has been divided up to be reviewed between institutions in different cities. The reviewers are not shown the full picture provided by the data. This limits their effectiveness and leads to inconsistencies in the information provided to the Task Force, allowing recommendations to be made in a more arbitrary manner.
The Task Force co-chair, who is also the chair of the breast screening guideline has made inappropriate statements to the media. She pre-judged the outcome of the evidence review update, showed a lack of objectivity, and a strong ideological bias against screening.
After the US Task Force announced that the screening age would be lowered to 40, and before the Canadian evidence review had even begun, Dr Thériault stated in the Toronto Star, and in other media that there was no need to change the screening recommendations based on her estimation that there was no new evidence.
She also stated, ?The Canadian Task Force does not intend to update guidelines set in 2018 because the benefits of earlier screening do not outweigh the risks of false-positive results and overdiagnosis when harmless tumours are detected.?
All task Force members should be selected for scientific expertise and any conflicts of interest should be declared and mitigated.
We believe the lack of impartiality of the Task Force leadership can undermine the credibility of its recommendations.
Many specialties share similar concerns about the Task Force. You can read more ici
Racial disparities: There are differences in the age distribution of cancer in different groups and the worse outcomes at younger age in racialized minorities. We need data to better inform decisions regarding screening for these groups are not routinely collected in Canadian statistics. A study with Statistics Canada shows all ethnicities other than white have a lower age of peak incidence in the 40s.
Here are some of the gaps in data collection.
Our Cancer Registry is missing critical data in order to be able to assess impacts of screening on cancer outcomes. The following are key gaps in data which need to be remedied:
Stage data is not available after 2017. Jurisdictions would need financial support to support collection of staging data.
Race/ethnicity information is not available for cancer cases.
A short-term solution would be to fund pre 2016 CanCHEC linkages (2006 and 2011) to CCR 2021. This would add 6 years of follow-up and potentially 6 more years of new cases.
Method of detection of cancer is not documented, i..e whether cancers are detected by screening or symptoms.
Breast density: documentation of ACR density category
A short-term solution would be the data acquisition of the CBCSD (Canadian Breast Cancer Screening Database) which contains both density and method of detection.
There are no incidence data for Quebec and Nova Scotia
Recurrence Data needed: documentation of which cancers are recurrences as opposed to registering as a new primary.
Summary of Dense Breast Canada's concerns.
- The Task Force panel has interfered with the evidence review group by dictating old studies (RCTs) from the 1960s to 1980s be included in the evidence review.
- The Task Force panel shows a poor understanding of the science as seen by their insistence on using old studies. These studies were conducted under conditions that are not reflective of modern cancer detection and treatment. One of the studies is corrupted.
- The Task Force continues to undervalue the demonstrated benefits of screening, and overemphasize so called "harms."
- Systemic racism is an issue due to the use of old studies that had predominantly white participants.
- 10/12 provinces/territories have lost confidence in the Task Force decisions and are making their own guidelines based on current evidence, leading to different practices across the country.
- There is silo-ing of information due to the use of multiple evidence review centres in the guideline making process.
- The Task Force is an arms length, independent body. However, it is missing a governance mechanism to oversee its procedures and ensure the well-being and safety of Canadians.
- The leaders of the Task Force appear to be biased. They seem to have a strong opinion about the harms of screening. They announced the result of the update before reviewing the evidence. Publicly, they said there's no need to change the guidelines from 2018.
- Similar concerns about the Task Force are held by various other specialties and can be read about ici
Recommendations.
- Rebuild the Task Force to include an accountability structure and governance mechanisms.
- Allow breast cancer screening experts and patients to vote on the final guidelines.
- Rebuild the Task Force to include transparency of the entire review process.
- Rebuild the Task Force to include ethics oversight and address the bias and impartiality of Task Force leadership
- Address gender and racial bias in the evidence review process and working group.
- Change the weighting of the evidence to emphasize more modern evidence that includes a diverse population.
- Address silo-ing from evidence review centres.
- Monitor outcomes of guidelines
- Address research gaps
Read our report
Concerns about the current Guidelines.
Pourquoi les directives de dépistage du cancer du sein sont trompeuses et dangereuses?
In May 2024, the Canadian Task Force on Preventive Health Care issued draft guidelines on breast cancer screening for women of average and moderate risk. These guidelines are used by 60,000 family doctors and nurse practitioners in their interactions with ~8 million women aged 40-74.
Here?s how the current guidelines put women?s lives at risk:
1. The guidelines do not heed expert advice: There are no breast cancer experts on the Task Force panel and no breast cancer screening experts vote on the recommendations.
2. The guidelines ignore the importance of screening for women in their 40s: 17% of cancers occur in the 40s and are more aggressive.
3. The guidelines in the past advised against breast self-exams: Ces examens sont une mesure importante que les femmes peuvent prendre pour augmenter la détection précoce du cancer du sein, en particulier chez les femmes dont les seins sont denses.
4. Les lignes directrices exagèrent les méfaits du rappel des femmes pour des tests supplémentaires après une mammographie. Environ 10 % des femmes sont rappelées pour des images supplémentaires, ce qui peut causer de l'anxiété. Le Groupe de travail considère que cette anxiété est nuisible, et l'utilise pour dissuader les femmes de se soumettre au dépistage. Cependant, une étude démontré que cette anxiété ne dure pas longtemps, et c'est un petit prix à payer pour déterminer si le cancer est présent ou non. Mieux vaut prévenir que guérir.
5. The guidelines ignore significant health benefits of early cancer detection: Le Groupe de travail ne reconnaît pas les avantages d'éviter la chimiothérapie, la mastectomie et le lymphœdème.
6. The guidelines undervalue current data: The Task Force over values outdated and flawed studies form the 1960s to 1980s. The obsolete studies estimate that women are 15% less likely to die if they have breast screening. However, current studies show a mortality benefit of 52%.
7. The guidelines do not act on the risks of breast density: Dense breasts increase the risk of developing breast cancer and increase the risk that cancer will be masked on a mammogram. The guidelines negate the benefits of supplemental screening for women with dense breasts.
8. The guidelines do not act on the earlier incidence of breast cancer in minority women: Women of race/ethnicity other than White have earlier peak age at diagnosis, higher proportions of breast cancer diagnosed under age 50, and a peak age of death younger than White.
8. On demande aux femmes de prendre des décisions au sujet des tests de dépistage qui pourraientt leur sauver la vie en se fondant sur des renseignements inexacts. En utilisant les nouvelles lignes directrices, qui exagèrent les méfaits et sous-estiment les avantages du dépistage, les femmes peuvent prendre des décisions qui pourraient mener à un diagnostic tardif, à des souffrances inutiles et à un mauvais pronostic.
10. The guidelines ignore the rising incidence of breast cancer in young women in Canada. in the past 34 years.
11. Women aged 40?49 in jurisdictions that do not include women in the 40s in screening programs have significantly higher proportions of stages 2, 3 and 4 breast cancer compared to their peers in screener jurisdictions.
12. Mammography screening programs for women ages 40-49 in Canada are associated with significantly higher 10-year net survival for women diagnosed with breast cancer.
13.Using The OncoSim-Breast microsimulation model (Canadian Partnership Against Cancer) to simulate a cohort of 1.53 million Canadian women born in 1975 showed that compared to no screening, screening mammography is associated with an absolute mortality reduction of 4.6 (biennial 50?74), 5.9 (biennial 40?74) and 7.9 (annual 40?74) fewer deaths per 1000 women. The absolute rate of diagnosis of advanced cancers (Stage 2, 3 and 4) falls in favor of earlier stages as the number of lifetime screens increases. https://www.mdpi.com/1718-7729/30/11/686
14 Using the OncoSim model, based on 2023 treatment standards, screening a cohort of women annually for breast cancer starting at age 40 to 74 saves the Canadian health care system $459.6M over these women?s lifetime with 3499 breast cancer deaths averted and 52367 life years gained. This translates into a savings of $1880 for every woman screened (Abstract 174) https://cslide.ctimeetingtech.com/breast24hybrid/attendee/confcal_1/presentation
15 The provinces/territories have changed their policies and are not following the CTFPHC guidelines. The provinces/ territories currently including women in their screening programs starting at 40 include BC, NS, PEI, NL, NB, and YT, and those starting at age 45 are AB and NWT. There are public commitments to lower the age to 40 in SK (2025) and ON (Fall 2024). Quebec: INESSS is reviewing the evidence. Manitoba is reviewing practices.
Canadian women and their family doctors deserve to have accurate information about the benefits of screening.