Deaths from cancer in the United States have declined 33% since 1991, which researchers attribute to substantial changes in cancer prevention and screening in the last decade.

The decline means 3.8 million cancer deaths were averted, according to a new American Cancer Society report.

The new findings, published in CA: A Cancer Journal for Clinicians, spotlight “an astounding 65% reduction in cervical cancer rates in women ages 20-24 from 2012 to 2019, following the introduction of the human papillomavirus (HPV) vaccine.”

“The large drop in cervical cancer incidence is extremely exciting because this is the first group of women to receive the HPV vaccine, and it probably foreshadows steep reductions in other HPV-associated cancers,” said Rebecca Siegel, senior scientific director, surveillance research at the American Cancer Society, and the lead author of the report in a society press release.

According to the report, the steady decline in the U.S. cancer mortality rate is attributed to reductions in smoking, an uptake in screening for breast, colorectal and prostate cancers, and improvements in treatments such as adjuvant chemotherapies for colon and breast cancers.

Adjuvant therapy is often used after primary treatments, such as surgery, to lessen the chance of cancer coming back, according to Mayo Clinic.

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The report also notes advances in the development of targeted treatment and immunotherapy have accelerated progress in lung cancer mortality.

While the trend of reduction in cancer deaths is ongoing, the report raises concerns about the rising incidence of breast, prostate and uterine corpus cancers, “all of which have a wide racial disparity in mortality and are amenable to early detection.”

Prostate cancer, the second leading cause of cancer death for men in the United States, increased by 3% per year from 2014 through 2019 after two decades of decline, according to the American Cancer Society press release.

“Most concerning is that this increase was driven by the diagnosis of advanced disease. Since 2011, the diagnosis of advanced-stage prostate cancer has increased by 4% to 5% annually and the proportion of men diagnosed with distant-stage disease has doubled. These findings underscore the importance of understanding and reducing this trend,” the press release states.