Explained: How did US cancer rates drop by 33% since 1991?

Over the past three decades (circa 1991-2023), the death rate from cancer in the US has declined by a startling 30 per cent. This amounts to about 3.8 million lives saved since 1991, according to research that was published in CA: A Cancer Journal for Clinicians. Even better, the studies show that the death rate from cancer decreased from 2019 to 2020 by 1.5 per cent, which contrasts sharply with other major illnesses.

Researchers have shown that cancer is not only a major issue affecting worldwide health but also the second-worst killer in the US, after heart disease. COVID-19 takes the third spot.

Over the course of the three decades (circa 1991-2023), researchers estimated that 2.6 million deaths in men and 1.2 million in women from cancer were averted. Men saw a 2.6 per cent annual decline in lung cancer incidence from 2015 to 2019 compared to women's 1.1 per cent yearly decline.

Young women's (20–24-year-olds) risk of developing cervical cancer has dramatically decreased, falling by 11.4 per cent between 2012 and 2019 and by a staggering 65 per cent overall within the same time frame.

Also read | Scientists find the chocolaty secret to chocolate's sweetness

Additionally, death rates for kidney cancer, melanoma, and leukemia decreased by two per cent year from 2016 to 2020.

The study found that the death rate has dropped over the previous three decades as a result of a dip in smoking and advancements in cancer diagnosis and treatment.

The American Cancer Society's CEO, Karen Knudsen, told CNN that the drop in cancer mortality is "truly formidable."

“New revelations for prevention, for early detection, and for treatment have resulted in true, meaningful gains in many of the 200 diseases that we call cancer,” Knudsen added.

The first vaccination against the two strains of the human papillomavirus, according to researchers, is to credit for the drop in cervical cancer cases (which cause 70 per cent of such cancers).

The vaccination was originally permitted for use in females between the ages of 9 and 26 in 2006 by the US Food and Drug Administration, as per researchers.

“This totally follows the time when HPV vaccines were put into use,” Dr William Dahut, the society’s chief scientific officer, told CNN.

Also read | Explained: In a first, scientists use artificial DNA to kill cancer cells: Here’s what you need to know

The report also stated that the first group who received these strains' immunisations are currently in their 20s.

Conclusively, these findings point to sharp future declines in HPV malignancies, the majority of which affect women.

“There are other cancers that are HPV-related – whether that’s head and neck cancers or anal cancers – so there’s optimism this will have importance beyond this,” Dahut added.

The latest research points out that occurrences of breast, uterine, and prostate cancer have been "of concern" and growing in the US, despite the fact that the overall cancer mortality rate has been steadily declining.

Cancer among adults under 50 may be on the rise globally. The research states that since the middle of the 2000s, the incidence rates of breast cancer in women have been rising by roughly 0.5 per cent per year.

Incidence of uterine corpus cancer has increased around one per cent year since the mid-2000s among women 50 and older and roughly two per cent annually since at least the mid-1990s among younger women.

After two decades of reduction, the incidence rate of prostate cancer increased by three per cent year from 2014 to 2019.

White House Cancer Moonshot Coordinator Dr Danielle Carnival stated in a statement issued on Thursday that the latest study "shows great progress."

President Biden renewed the White House's "Cancer Moonshot" project last year, pledging the country to aim toward cutting the death rate from cancer by at least 50 per cent over the following 25 years.

“The report showing the US has cut cancer deaths by one-third over the last 30 years is great progress, which we’ve achieved through driving smoking rates down, improving early detection, and delivering better treatments for many cancers. It means millions of American families have been spared the immeasurable loss of a loved one,” Carnival said in a statement quoted by CNN. 

“The report also underscores that there’s more work to do to save more lives,” she said. “President Biden’s vision for ending cancer as we know it is building on the progress we’ve made with an all-hands-on-deck effort to develop new ways to prevent, detect, and treat cancer – and ensure that the tools we have and those we develop along the way reach all Americans.”