While deaths from all forms of cancer dropped nationally by 20 percent over the past 35 years, a new study shows that death rates actually increased in some U.S. counties, including in rural areas of Tennessee, Kentucky and other parts of the South.
The death rate varied depending on the type of cancer, but was particularly striking for lung cancer. Kentucky led the nation with 85 deaths per 100,000 people, followed by West Virginia with almost 77 deaths, and then Tennessee, Alabama, Mississippi and Arkansas, all in the 72-73 deaths per 100,000 people range. Utah had the lowest rate, at 26 per 100,000, while California, Colorado and New Mexico were all in the mid- to high-30s.
But the data is even more striking when viewed at the county level. Hamilton County, for example, has a lung cancer death rate of 60 per 100,000, compared to 106 for Polk County and less than 41 for wealthy Williamson County, in the Nashville suburbs.
Dr. Gustavo Miranda-Carboni, a cancer researcher at the University of Tennessee Health Science Center in Memphis, said that when he reviewed the study, he was particularly struck by a large cluster of dark red along the Mississippi River near Memphis. The red showed counties where the cancer death rate had gone up the most in the past 35 years.
"After reading the study, I walked into my colleagues' offices and said, 'Look at this. This can't be normal. We have an exploding rate of aggressive cancers,'" he said.
Whether or not a person gets cancer often depends on a number of different factors, including genetics, environment, diet, and whether someone has other negative health factors like obesity or smoking.
When researchers looked further at the counties where the cancer death rate was growing, they saw some important overlaps with other key factors.
"Rates of smoking vary very widely across the country," said Dr. Laura Williams Goff, a cancer specialist at the Vanderbilt University Medical Center, "and in some Tennessee counties, the rate is nearly double the national average."
The map was very similar for obesity.
"For prostate and for breast cancer, you have obesity as a factor," Miranda-Carboni said. "If you were to map the obesity map over the cancer map, the mid-South and South have the highest rates of obesity."
But Miranda-Carboni said it appears that there is at least one more factor involved in why the death rate from cancer has increased in certain Tennessee counties and not elsewhere: access to health care.
"If you catch it early, with most any cancer your chances of surviving are really, really good," he said. "But when you catch it at Stage 3 or Stage 4, there is not much we can do to prevent the ultimate outcome."
Too many people who either can't afford health care or don't have easy access to it in the rural areas where they live discover their cancer too late, he said.
One discouraging conclusion from the study, which was published in January in the Journal of the American Medical Society, was that liver cancer increased in almost all counties over the past 35 years, including in Tennessee.
"I take care of a lot of liver cancers, and with the prevalence of hepatitis C and of obesity, we are seeing a rise of liver cancer," Vanderbilt's Goff said. "Now there are recommendations that all baby boomers should be screened for Hepatitis C because the prevalence is so high." As with lung cancer, Hepatitis C can be cured if it is discovered early enough.
Goff said too many people wait too late before changing their bad habits.
"Things like healthy eating, exercise and not smoking are all things we know we should be doing," she said. "My patients are looking for what they can eat when they already have cancer, when people need to worry about what they can eat before they ever have cancer."
But Miranda-Carboni said he hopes the JAMA study will give doctors and medical researchers a tool to lobby both patients and lawmakers to take preventive measures.
"The reason I was recruited here, is that there is a dire need to address the health disparities of this region," he said. "This is the beautiful part of this study — to say where can we control a particular factor, avoid these choices, prevent this, then we will see a radical change in the number of these specific types of cancers."