By DR. ROSE MARIE LESLIE, ABC News(NEW YORK) — Cancer is one of the most important health challenges our nation faces and the second leading cause of death in the United States. Now, a new study from the American Cancer Society finds that the rate of cancer-related deaths has been steadily falling over the past two decades, with dramatic declines in the past two years.The American Cancer Society, however, warns that the future is uncertain. With many Americans hunkered down at home and missing their annual cancer screenings, it is unclear how the COVID-19 pandemic will affect this positive trend.Looking back over the past three decades, the study found that the rate of cancer-related deaths decreased 31% between 1991 and 2018. Between 2017 and 2018, there was a record-breaking decline of 2.4%. The researchers predict that over 3 million lives have been saved since 1991 because of this decline in the death rate.“We are not only continuing to make progress in cancer mortality in U.S., but that progress has accelerated,” said Rebecca Siegal, the lead author of the American Cancer Society study.This progress is likely due to many factors, including decreased smoking rates and improved screening and treatment for certain types of cancer. This has led to a decline in cancer rates associated with many major cancers, including lung cancer, breast cancer, prostate cancer and colorectal cancer.One of the most significant drops in the death rate has occurred in lung cancer, which is currently the deadliest cancer in the United States. The report attributes this to both a decrease in smoking and improvements in lung cancer treatment, specifically for a type of lung cancer called Non-Small Cell Lung Cancer.“This is really exciting because lung cancer is the third most likely diagnosed but it is the leading cause of cancer by far,” noted Siegal.Although many advances in cancer prevention, screening, and treatment have been made, there are still areas for improvement.One area requiring improvement: preventable cervical cancer deaths. There are two highly effective tools to prevent this cancer, including the HPV vaccine and screening for cervical precancers with the pap smear exam. Despite this, about 11 women die of cervical cancer per day in the United States, over half of them under the age of 50.“This cancer we can screen for it, and not only can we screen for it, we can prevent it. We know what to do, we just have to get a whole lot better at actually doing it,” said Dr. Deborah Schrag, chief of population sciences at Dana-Farber Cancer Institute and a professor of medicine at Harvard Medical School.Another area that needs improvement is the gap in cancer-related deaths between Black and white Americans. Currently, Black Americans are 13% more likely to die from cancer than white Americans. The reasoning behind this is complex.“It honestly boils down to decades and decades of systemic racism,” said Siegal. “People who are African American are not only diagnosed at a later stage for almost every cancer type, but even within each stage of diagnosis their survival is lower. This is not something related to biology for the most part … but this is largely because of reduced access to care.”Beyond looking at prior cancer data, the report also predicts cancer trends for the upcoming year. This year’s predictions, however, don’t take into account the COVID-19 pandemic and its potential impact on these numbers.“It is strongly expected that disruptions of care in 2020 that continue into this year will increase diagnosis of advanced stage disease and cancer mortality. But that will play out over many years,” said Siegal. “This will make prediction of cancer trends over the next few years difficult.”Despite the uncertainty regarding the impact of the COVID-19 pandemic, significant improvement in cancer-related mortality has been made.“When we take the long view and look over the past two decades, there is reason for tremendous optimism … progress has been made and we would be remiss if we didn’t celebrate that,” said Schrag.Copyright © 2021, ABC Audio. All rights reserved.