The news
Cancer deaths in the United States are declining, and four million deaths have been prevented since 1991, according to the American Cancer Society’s annual report. Report.
In the year Society reports that by 2023, more than 1.9 million new cancer victims will reach more than two million. Cancer remains the second leading cause of death in the United States after heart disease. Doctors believe that it is urgent to understand the changes in the death rate as well as the changes in cancer diagnoses.
Background: Treatment improvements can help reduce cancer mortality.
The cancer society has highlighted three main reasons for the reduction in cancer deaths: reduced smoking, earlier detection and much improved treatments.
One area where treatment has had the greatest impact is breast cancer mortality.
In the year In the 1980s and 1990s, metastatic breast cancer was “considered a death sentence,” said Donald Berry, M.D., a statistician at the University of Texas MD Anderson Cancer Center and a new author. Paper Sylvia K. Plevritis from Stanford University and other researchers on breast cancer (many of the authors of the paper said they received payments from companies involved in cancer treatment).
In 1975, 48 per 100,000 women had fallen to 27 per 100,000 women in 1975, the paper, which appeared in Jama on Tuesday, confirmed. This includes metastatic cancer, which accounts for nearly 30 percent of breast cancer reductions. Death rate.
Ruth Etzioni, a biostatistician at the Fred Hutchinson Cancer Center, said breast cancer treatment has improved so much that it has become more about saving lives than screening.
Dr Matt Callagher, professor of medicine at the University of Oslo and Oslo University Hospital, said the lower death rate among women in their 40s who generally did not have regular mammograms, “shows a significant effect of the treatment”. .
“The biggest untold story in breast cancer is how much treatment has improved,” said Dr. H. Gilbert Welch, a cancer epidemiologist at Brigham and Women’s Hospital. “This is unequivocal good news.”
What we don’t know: the cause of new cancers.
The American Cancer Society notes an increase in the incidence of many cancers, including cancers of the breast, prostate, uterus, oral cavity, liver (in women but not men), kidney, and colon and rectal cancer. The elderly. The incidence of melanoma has also increased. The numbers are adjusted for changes in population size.
The Cancer Society’s chief scientific officer, Dr William Doughty, is concerned that while overall colorectal cancer rates are falling, the number of people in one group under the age of 55 is increasing. The incidence is now 18.5 per 100,000 and has been growing from 1% to 2% per year since the mid-1990s, and 30,500 people are expected to be infected this year.
In the year In the late 1990s, colorectal cancer was the fourth leading cause of death for people under the age of 50. Doctors cannot say why.
“We don’t have a good explanation,” Dr. Dout said. “We do a lot of hand-wringing. Is it diet? Is it obesity? Is it something in the environment? Is it in utero?
But colorectal cancer is a cancer of the elderly — among those over the age of 65, it’s declining by 3 percent a year, according to the Cancer Society. The incidence is now 155.4 per 100,000 and 87,500 people are expected to be diagnosed this year.
Facts to remember: Cancer incidence can be difficult to interpret.
Cancer researchers say that the more you look for cancer, the more you will find. As screening becomes more sensitive, doctors are finding more and more cancers.
That sounds like a good thing – wouldn’t it be better to get rid of cancers before they become dangerous? The problem is that sometimes treatment may be unnecessary because every cancer can be life-threatening or even undiagnosed. Some cancers never spread. Others will go. Others may eventually have a fatal outcome, but one dies first of something else. But it is impossible to distinguish harmless cancers from deadly ones, so they are all treated.
The condition is called overdiagnosis, but no one can say exactly how often it happens. With mammography, according to Dr. Berry, the estimate of overdiagnosis ranges from 0 to 50 percent.
“The increase in the disease is always in the foreground, but we need to understand why they occur because they can be hereditary,” said Dr. Izzioni.
That’s the challenge cancer researchers now face.