CHATTANOOGA, Tenn. >> Even though she’s now cancer-free, the anger shows when Flower Scalia, 35, remembers being diagnosed.

Raised in California, she had been living in Chattanooga for almost 20 years, working as a dental assistant and helping her husband at the shoe repair shop his family has operated since 1906. She knew she was sick — she was nauseous and losing weight — but her doctor couldn’t figure out what was wrong with her.

“He blew me off for nine months,” Scalia said in a recent interview. It wasn’t until July 2012 she learned she had colon cancer.

The next year was difficult.

First, she had chemotherapy and radiation to shrink the cancer, but the treatments made her sick.

“My husband would take me to radiation, then he would go to work,” Scalia said. “I lived on the couch.”

Her small dog, Oscar, lay on her stomach for much of every day, she said.

“He got me through some really dark places, alone with my chemo pump, (being sick) and all of that. My biggest fear was that my girls would get off the (school) bus and find me dead on the couch.”

Surgery removed the tumor, but the follow-up chemo treatments were too much for Scalia. Again nauseous and miserable, she talked to her doctor and quit after only two treatments.

Now, almost five years after she was diagnosed, Scalia is cancer-free. She plans to take balloons and cake to her doctor July 20, the anniversary of the day she was diagnosed.

But there may be a reason why Scalia’s first doctor didn’t quickly recognize her colon cancer. Colon cancer is normally only seen in people aged 60 or older. In fact, the American Cancer Society recommends people get their first screening for the disease when they are 50.

“It is still thought of as a disease of age 60 and later,” said Kim Shank, a colorectal nurse navigator at CHI Memorial’s Rees Skillern Cancer Institute, who worked with Scalia.

But a recent study by the American Cancer Society and the National Cancer Institute showed that while the chances of someone young getting colon cancer are still slight, they have increased significantly in the last 40 years, and doctors are not certain why. The study examined more than 490,000 people age 20 or older who developed colon or rectal cancer between 1974 and 2013. People 50 years old and older showed a decline, which researchers believe is linked to increased screening.

But compared to a baby boomer born around 1950, those born around 1990, often referred to as millennials, have double the risk of colon cancer and four times the risk of rectal cancer. The risk is still slight — you’re 20 times more likely right now to get colon or rectal cancer if you are a baby boomer than a millennial — but what is troubling to doctors is the trend.

In their study, the cancer researchers said the recommended age for screening might need to be lowered. Already, African-Americans, who seem to be more vulnerable to colon cancer, are told to begin screenings at age 45.

But too many people who are experiencing the possible symptoms of colon cancer, including rectal bleeding or abdominal pain, are reluctant to see their doctors.

“Not many people want to see their doctor about anal or rectal problems,” said Dr. Eric Nelson, a colorectal surgeon with University Surgical Associates in Chattanooga. “They sometimes think it is embarrassing, and that prevents patients from getting checked. But it is very important that people try to put that aside and realize it is a common medical problem, and many people have it, so go and see a doctor.”

Most of the time, the cause will not be colon cancer, Nelson said.

“All of these things are not normal, but most of the time it is not cancer. But it is important to find out the cause.”

Often a screening will discover a growth, or polyp, in the colon that may later become cancerous. But it is easily removed if discovered earlier.

As with many other cancers, if people delay in getting diagnosed, their treatment may be much more difficult, or even impossible. Colon and rectal cancer is the third leading cause of cancer-related deaths in women in the U.S., according to the American Cancer Society, and the second leading cause in men, resulting in an estimated 50,000 deaths during 2017.

While researchers do not know for certain why the rate of colon and rectal cancer is increasing in younger people, they suspect both genetics and diet.

“The phrase we use is ‘genetics loads the gun but lifestyle pulls the trigger,’” Nelson said.

If several family members have developed colon cancer at an early age that would be a clear warning sign, Shank said.

“People that have a strong family history with multiple family members who have colon cancer are at increased risk. But they are also at higher risk in people who are obese and who have a high-fat, low-fiber diet. And there is an increased risk for people who have things such as an inflammatory bowel condition, Crohn’s disease, or colitis.”

Researchers are suspicious, she said, that “there’s going to be proven a strong link to the diet that millennials and Gen Xers have been on — processed food, convenience food, less fresh fruits and fresh vegetables.”

That does not necessarily mean they are overweight.

“At a young age, you don’t have to be obese to have a poor diet,” Shank said. “You can look like you have a healthy weight, but your diet is processed food.”

That makes sense for Scalia. At Shank’s urging, she has joined an exercise program at the YMCA and she now pays attention to “all that crap you put in your mouth.”

“I do have a pizza here and there, but I try to buy everything organic,” she said. “I like smoothies from Whole Foods.”