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By Kate Yandell

SciCheck Digest
Breast cancer in younger women has been increasing gradually in recent decades. But a social media post misrepresents case number projections for 2022 and 2023 to falsely claim they show a dramatic rise in early-onset breast cancer — and then baselessly ties its faulty comparisons to COVID-19 vaccines.


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Breast cancer in American women under 50 increased gradually from the mid-1990s through 2019, with a somewhat steeper rise starting in 2016. The rate of female breast cancer also rose slowly in older women from the mid-2000s through 2019.

Researchers say these changes were likely at least partly due to changes in when people begin having children and, for older women, increasing body weight. Being overweight after menopause or having children later in life increases the risk of breast cancer.

Breast cancer incidence fell for all women and women under 50 in 2020, likely because disruptions to health care appointments during the pandemic led to missed diagnoses. The year 2020 is the latest one for which official federal statistics on cancer incidence are available.

The American Cancer Society, a nonprofit organization, provides estimates of annual new cancer cases through 2023, but these projections are based on models using data from 2019 and earlier. 

Yet a popular post on TikTok, which also was shared on Facebook, misrepresents these ACS projections, using them to give the false appearance of a large spike in breast cancer cases in women younger than 45 in 2022 and 2023. 

Dr. Ilana Richman, a general internist and health services researcher at Yale School of Medicine who studies cancer screening, told us via email that “there are a few clear misrepresentations” of the breast cancer case numbers cited in the video.

The video compares projections for breast cancer cases in different age groups while leading viewers to believe they are being shown case numbers just for women under 45.

“Something’s going on here … ’22 and ’23, there is a huge boom in cancer, especially in female breast cancer in younger ages of 45 and down below,” states TikTok user James Bishop, a self-proclaimed “numbers guy” who identifies himself as a husband, father, musician, retired firefighter, paramedic and educator.

But Bishop is wrong. The supposed “boom” in breast cancer is based on a comparison between projected case numbers in women under 45 a few years ago to later projected estimates for all women or those under 50.

Further, the ACS projections are not meant for assessing trends in cancer incidence. And the ACS states that these estimates do not “reflect” or “account for” the effects of the pandemic.

The post also implies that COVID-19 vaccines led to increased breast cancer risk in 2022 and 2023, but there is no evidence of an increased risk of cancer following vaccination. “[T]here is no mechanistic reason why covid vaccines would cause cancer,” Richman said.

Video Falsely Portrays Data on Frequency of Breast Cancer

The video misleads in part by showing blurry images of ACS tables and making it appear that various numbers are comparable.

For 2019 through 2021, Bishop correctly says that ACS projected about 26,500 new cases of breast cancer each year for women under 45. But for 2022, he misleadingly gives a projection — 47,550 — for women under 50. He does not make it clear that this number reflects a wider age range, instead claiming that the cases are “double.”

“There are about 10 million women in the US between age 45 and 50. So shifting the age cutoff from 45 to 50 increases the population size in that age group and of course will result in a larger number of cancer cases being reported,” Richman said. “Women age 46-50 are also at higher risk of breast cancer than women 45 and younger.”

Female breast cancer risk increases until a woman is in her 70s, according to an ACS report that uses data from the National Cancer Institute and Centers for Disease Control and Prevention. A woman’s chance of getting breast cancer is 1 in 1,439 in her 20s, 1 in 204 in her 30s, 1 in 63 in her 40s and 1 in 41 in her 50s, the data show.

The ACS estimates for total female breast cancer cases projected a slight annual increase in cases, but no “large jump,” Richman said. “So bottom line, there is no large increase in cancer cases in 2022. The ACS simply changed the age groupings it used,” she added.

The video continues to grossly mislead, with Bishop highlighting the number 297,000 on a table for 2023 and saying, “and the year ain’t over yet.”

But 297,790 is the projected number of new breast cancer cases in all women in the U.S., not just women 45 and under, which Bishop does not make clear. And this is the projected number of cases for the entire year of 2023, not just the year so far. 

“Most breast cancers occur in women older than 45 so of course the number of cases will be much higher in the total US population,” Richman said.

Again, Richman said, the total case projection is “not that different” than in past years. “It is somewhat higher but not by a factor of 10, like he is insinuating,” she said, referring to the implication that the number of cases skyrocketed in 2023 compared with 2019 through 2021.

The video claims that an equivalent table is not yet available for 2023, but it is. For women under 50, the projected number of new cases is 48,780. As we said, ACS’ 2022 projection was 47,550. And ACS’ projected total new cases for 2022 was 287,850, not radically different from the 2023 estimate of 297,790. 

Again, these are projections, not figures that represent actual reported cases, as Bishop makes it seem.

Photo by Pixel-Shot / stock.adobe.com

It’s important to note that the data Bishop is inaccurately presenting isn’t meant to be used to infer trends in cancer incidence in the first place. The tables providing projected cases by age group say at the bottom: “Note: Estimates should not be compared with those from previous years.” This is because these estimates are based on modeled data “and vary from year to year for reasons other than changes in cancer occurrence,” ACS says elsewhere on its website.

For instance, ACS says it updates its models over time, and changes in methodology could lead to apparent changes in cancer incidence.

Richman pointed out that breast cancer case numbers depend on factors such as the size of the population and whether it is aging — a growing or aging population will lead to a higher number of breast cancer cases. This is why it is better to monitor changes using data on incidence, or the “number of cases per person over a defined period of time, often adjusted to account for differences in the age composition of the population over time,” she said.

Further, the ACS case projections rely on past incidence statistics from the North American Association of Central Cancer Registries, which draws on data collected by the NCI and CDC. These data provide a comprehensive sense of cancer incidence in the U.S., but the availability of the data lags by several years.

All of the case estimates mentioned in Bishop’s video are based on modeling that relies on data from before the pandemic, so these models would be unable to pick up on any pandemic-related trends. 

Researchers expected that disruptions in access to health care due to the pandemic may have led to a temporary decrease in cancer incidence, due to delayed or missed screenings, follow-up appointments and appointments to ask about new symptoms. 

As we’ve said, this decrease in incidence is now showing up in the most recently available comprehensive national data. Researchers have hypothesized that an increase in cancer cases may show up in later data as diagnoses are made that were previously missed.


Editor’s note: SciCheck’s articles providing accurate health information and correcting health misinformation are made possible by a grant from the Robert Wood Johnson Foundation. The foundation has no control over FactCheck.org’s editorial decisions, and the views expressed in our articles do not necessarily reflect the views of the foundation.

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