AMNA NAWAZ: Well, if you're under the age of 50, it's likely that colorectal cancer isn't on your radar, but it should be.

Once considered an older age disease, rates are skyrocketing among young adults.

Deema Zein has more.

DEEMA ZEIN: This year, an estimated 108,000 people in the U.S.

will be diagnosed with colon cancer.

That's according to the American Cancer Society.

And one in five are young, under the age of 55.

I spoke with two people who were diagnosed at an early age.

Here's some of what they told us.

CHRISTIE GARRECHT, Diagnosed at 31: My name is Christie Garrecht.

I am from Long Island.

I am currently 34 years old.

I was originally diagnosed with stage 3C colon cancer.

And I am currently stage 4 young onset sporadic MSI colon cancer.

And I am currently still in treatment three years later.

IMTIAZ HUSSAIN, Diagnosed at 26: My name is Imtiaz Hussain, diagnosed at the age of 26 in 2020.

And I was diagnosed with colon cancer stage 3B.

CHRISTIE GARRECHT: I think I was just in complete shock, because having no family history of cancer ever, never expected it.

The past month-and-a-half, I have been in and out of the hospital with different reasons, because the tumors have been causing pain in my back.

They have been causing pain in my ribs.

I have had an allergic reaction to the medications.

And chemotherapy is not easy.

IMTIAZ HUSSAIN: I never thought that I would have cancer, because I was like just young 26 years old, you know?

And it was heartbreaking.

Throughout the time when I started my treatment, I think that my health started going down, you know?

That part was one of the hardest because I was the breadwinner of the house, you know?

And not being able to go out and work and not being able to provide for my family, and somebody, my wife, have to take care of me.

CHRISTIE GARRECHT: My life has been stripped from me.

Chemotherapy has stripped my life.

And it's been very tough mentally, physically, and all the way around.

IMTIAZ HUSSAIN: The first time I got my bleeding, I should have gone to colonoscopy, because I ignored it.

I got my bleeding.

I started bleeding seven months prior to I got diagnosis.

When I went to my doctor, I should have asked for a colonoscopy.

They thought that it was just ulcer.

CHRISTIE GARRECHT: This is not OK.

In your 30s, your 40s, in your 20s, you're just starting off your life.

You're just starting.

I mean, I'm a single homeowner.

I just started my career nine years ago.

It's -- this is not something you plan for.

You have these big dreams of having a family, getting married, buying a house.

You don't factor in cancer.

DEEMA ZEIN: Joining us to discuss this further is Dr.

Robin Mendelsohn, a gastroenterologist at Memorial Sloan Kettering Cancer Center and co-director of the Center for Young Onset Colorectal and Gastrointestinal Cancers.

Dr.

Mendelsohn, thank you so much for joining us today.

DR.

ROBIN MENDELSOHN, Memorial Sloan Kettering Cancer Center: Thank you for having me.

DEEMA ZEIN: Can you give us a sense of how much colorectal cancer is rising in young patients today?

DR.

ROBIN MENDELSOHN: We have actually been seeing it since the 1990s, and it's been increasing by about 3 percent per year.

As we heard from those two patients, the majority of these patients don't have a family history.

We used to think, oh, you're young, and you have colon cancer.

Has to be a genetic component.

There has to be about -- a family history.

But only about 10 to 20 percent will have a family history or a genetic predisposition.

So the majority are what we call sporadic, so with no known risk factors.

We are actively trying to figure out why this is happening.

DEEMA ZEIN: And so we're talking about this.

Who is most at risk then and what are the symptoms that people need to be watching out for?

DR.

ROBIN MENDELSOHN: Yes, so even though the numbers are increasing, the majority of people with these symptoms will not have cancer.

But, as we heard, the number one symptom is rectal bleeding.

And we say any rectal bleeding that's persistent.

So anything more than a couple of weeks should definitely get checked.

Again, the majority of people with rectal bleeding will not have cancer, but should definitely be evaluated.

Other symptoms are abdominal pain or distension that's new and not going away.

Changes in bowel habits.

So anybody that's had normal bowel habits and is suddenly constipated or has been constipated their whole life and now has diarrhea.

Unexplained weight loss, so losing weight without meaning to.

And if you're found to be anemic on your blood work, so if your hemoglobin or your blood count is low, sometimes, that can mean that the cancer is shedding blood into the stool, and that's why your blood count can be low.

DEEMA ZEIN: And both of the patients that we spoke to had more aggressive stages when they were diagnosed.

Are we seeing people, especially these young people, being diagnosed at these later, more aggressive stages?

And if so, why?

DR.

ROBIN MENDELSOHN: Yes, we are.

So the majority of these younger patients will present at later stages, at stage 3 or 4.

And that's because they're presenting with symptoms.

So, when it's early stage, stage 1, there's usually no symptoms, and that's when we usually pick it up on screening.

So when people who are in our screening age group, which is 45 or older, when we do find cancer on screening, because they don't have symptoms, the majority are found at early stages, where it is very, very treatable and curable.

Unfortunately, once symptoms develop, that usually indicates that it's a later stage.

DEEMA ZEIN: And I know you mentioned there's not one factor that we're finding to cause this colorectal cancer in young patients, but is there something that people can do to protect themselves to lower their risk factor?

DR.

ROBIN MENDELSOHN: Yes, so the traditional risk factors of colorectal cancer in average onset, so over 45, also hold true for the younger groups.

So, obesity.

Obesity is associated with colorectal cancer.

And when you look at younger patients, there are some patients that are obese.

When we look back at our patients at Memorial Sloan Kettering, they were more likely to be overweight and obese, but when we compared them to a national cohort without cancer, they were actually less likely to be overweight and obese.

So, even though obesity is a risk factor, it's definitely not the entire answer, but trying to maintain a normal body mass index is helpful.

It's also associated with diets that are high in red meats and processed meats.

Again, many of these patients that we speak to do not eat red meat or processed meats.

They're vegetarian or even vegan and adhere to what they consider a healthy lifestyle.

But, in general, avoiding red meats and processed meats, sticking to a diet that is high in fruits and vegetables, also increasing physical activity and avoiding alcohol and tobacco.

DEEMA ZEIN: And if someone is unfortunately diagnosed with colon cancer, what steps should be taken and how critical is it to catch it early?

DR.

ROBIN MENDELSOHN: So, the earlier you catch it, the more treatable and beatable, but even at later stages, we do have options.

So it's important that, when diagnosed, to go to a center that's high-volume and is seeing these patients.

There's different treatments based on the pathology, what it looks like under the microscope.

There's different treatments depending on where it is in the colon.

So, the majority of our younger patients are presenting with cancers that are lower down in the colon, in what we call the left colon or the rectum, and those might be -- those are treated differently sometimes than those that are at the top of the colon.

So it really depends on where it is in your colon, how much is involved what the options are, but there are options for all stages, but the earlier that it's caught, the better the outcomes.

DEEMA ZEIN: Thank you so much, Dr.

Robin Mendelsohn.

Appreciate your time.

DR.

ROBIN MENDELSOHN: Thank you.

AMNA NAWAZ: For more on this topic, tune into next weekend's episode of "Horizons," when William Brangham will take a closer look at rising rates of multiple types of cancer in young people and what can be done to prevent it.