Kathy Shelby was 8 years old the first time cancer crept into her Christmas.
"I just remember waking up early Christmas morning, and it was snowing," she said.
They rushed Shelby's mother, Carmie Cagle, from the family farm in Parsons, Tenn. — a small town between Nashville and Memphis — to a hospital in Jackson. There, after spending two weeks, 37-year-old Cagle was diagnosed with colon cancer.
"They sent her home to die," Shelby said.
Despite a grapefruit-sized tumor and a grim prognosis, Shelby's mother lived to be nearly 92. But her journey wasn't easy.
Cagle's colon cancer returned in her 40s, followed by uterine cancer, and colon again in her 50s. Eventually, ureteral cancer claimed her life last December.
"She was a feisty one — she was a little fighter to the very end," Shelby said, adding that the only time she saw her mother cry was days before passing away in Shelby's Chattanooga home, surrounded by loved ones.
This Christmas, cancer is once again rearing its ugly head. Shelby's son, Derek Hinson, is currently undergoing chemo- therapy in Albany, Ga.
"We just pray that everything goes well and we have him, like my mom, for many years to come," she said.
Shelby's family history is riddled with cancer, including herself, who was diagnosed with colon cancer and endometriosis at age 39. Before Cagle died, she identified about 30 relatives on her mom's side with various forms of the disease.
"People were calling here even last summer asking family history," Shelby said. "She kept up with everything."
Like his grandmother, this isn't Hinson's first cancer battle. In 2013, severe gastrointestinal bleeding from undiagnosed colon cancer left Hinson fighting for his life. He was 41.
"We almost lost him," Shelby said.
Cancer is caused by genetic mutations that create abnormal cells, which multiply and destroy parts of the body. Typically, these mutations are triggered by environmental factors — like radiation, some viruses and chemicals — or unhealthy lifestyle choices, such as smoking.
But between 5 and 10 percent of gene mutations are inherited, which prompted one of Cagle's physicians to recommend genetic testing. In Feb. 2016, Catherine Marcum, a genetics expert at CHI Memorial, evaluated Cagle.
The test identified a rare genetic condition called Lynch syndrome that carries a high risk of colorectal and other cancers, including uterine, ovarian, skin, breast and brain cancer.
About 140,000 people are diagnosed with new cases of colorectal cancer each year in the United States, and about 3 percent of those cases are due to Lynch syndrome, according to the U.S. Centers for Disease Control and Prevention. There's a 50 percent chance first degree relatives — parents, children and siblings — of someone with Lynch will also have the syndrome.
"We always knew we had lots of cancer in our family, we'd just think it's hereditary, and so I didn't go back and get the results," Shelby said, until her son moved and was searching for an oncologist in Georgia.
"I said, 'I really need to get that information,'" Shelby said. "Two hours later, Dr. Marcum, who I'd never met, never spoke to, she called me. She said, 'Kathy, you really need to come get your mother's test. It's been laying on my desk for months, and we need to talk.'"
Shelby sent her mother's results straight to her son's new oncologist, who immediately scanned Hinson upon learning of his grandmother's Lynch diagnosis. Tests revealed Hinson's cancer had metastasized, or spread to other parts of his body — something that Shelby believes would've otherwise gone unnoticed.
"I think divine intervention came in," Shelby said.
The growing field of cancer genetics is revolutionizing physicians' ability to detect and treat cancer, said Dr. Manoo Bhakta, chief of pediatric oncology and hematology at Children's Hospital at Erlanger.
"There's been a massive advance in genetics in cancer in the past decade, and the cost of testing is lots cheaper, so a lot of oncology is focused on not just treating cancer, but identifying those at risk," he said.
Although Marcum deals only with adult cancer, she said that families with Lynch may need to consider early cancer screening for children when appropriate.
"The whole reason that we do what we do is to find those families that are at risk of inherited cancer and to develop their surveillance and medical plan and care so that we can reduce risk," Marcum said. "Hopefully we don't have 20-year-olds dying from colon cancer that could've been prevented had those families known."
Marcum spent 30 years as a critical care nurse before she was captivated by genetics during her doctorate program.
"It's the future of medicine," she said. "I just happened to be traversing the path at the right time."
To complete a medical family history pedigree, Marcum complies information from an extensive questionnaire, interviews, death certificates, pathology reports and sometimes body tissue. The full summary maps out a family's history spanning three generations.
"It's like putting a puzzle together," she said.
Since hereditary cancer is uncommon, most patients' genetic test results are negative, but when tests do reveal genetic mutations, Marcum creates a medical plan, keeps close tabs on her patients and maintains an active role in support and advocacy.
"Our patients are given a pretty hefty diagnosis — it's not an easy pill to swallow," she said. "We're here for them. We're not just testing, giving a result and walking away."
Shelby has spent the year since her mother's death sifting through old belongings, photos and spreading the word.
"If you've got a history, if you've had any cancer in your family, or if somebody at a young age had cancer, like my family has, you need to talk to your primary doctor or go for genetic counseling," she advises. "It's a whole lot worse not knowing."
Marcum said one of the greatest benefits of her work is that it gets families talking.
"Maybe you knew that you had a cousin on your father's side that died at 30, but nobody ever asked, 'why did that cousin die at 30?' So it causes you to start a dialogue," she said.
Shelby used to think she took after her father, a jack of all trades who tended an orchard, ran a general store, was a carpenter and bus driver, and that seems fitting. Despite her family's medical challenges, Shelby juggles work and family time, which includes caring for an adopted son and two foster children.
But as she gets older, she's started seeing more of her mother's side.
"I hope that I'm just as spunky as she was," Shelby said. "I don't know if I will be or not, but I hope I am."
Contact staff writer Elizabeth Fite at firstname.lastname@example.org or 423-757-6673.