fbpx Colorectal Cancer Staging, Treatment and Life After

Colorectal Cancer Staging, Treatment and Life After

More than 151,000 Americans will be diagnosed this year. Find out what happens afterward.
Kurtis Bright
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Kurtis Bright

On the surface, you might be hard-pressed to come up with a connection between "Peanuts" comics creator Charles Schulz, reality show matriarch Sharon Osbourne and actor Chadwick Boseman of "Black Panther" fame.

Dig a little deeper and you'd find all were diagnosed with colorectal cancer, the third most common type of cancer, excluding skin cancers, in the United States.

Like Osbourne, some of the 151,000 Americans who will be diagnosed with the disease in 2022 will survive for a long time after they hear the words, "You have cancer." But like Boseman, many will die too young; he died in 2020 at age 43. Schulz also died of colon cancer, in 2000, at age 77. This year alone, another 52,000 Americans will succumb.

March marks Colorectal Cancer Awareness Month, a time when healthcare professionals encourage people in higher-risk groups to get screened for the deadly disease.

As discussed in the first installment of this series, screening is relatively inexpensive, accessible and painless. Not only that, a colonoscopy screening involves excising any polyps that could potentially develop into cancer.

But what happens if you're one of the unlucky 151,000 who does get colorectal cancer? What do you need to know?

Here, you can learn about the staging of cancer, the typical procedures performed depending on the stage and what life is like afterward.

Colorectal cancer staging

"Staging cancer" refers to the way healthcare providers assess the type of cancer and the extent to which it has developed. This analysis is crucial to determining a path forward in treating colorectal cancer, as recommendations vary greatly.

"Usually with colon cancer, everything starts with colonoscopy," said Shahrad Hakimian, M.D., a Los Angeles-based gastroenterologist and internist with UCLA Health. "We typically get some tissue samples and have our pathologist look at it and confirm that it's colon cancer. Many times we need further imaging, like a CAT scan, to look at the chest to see if there's any local or distant spread."

That's where staging comes in.

Determining colorectal cancer stages

The stages of colorectal cancer are defined using the TNM classification system.


The T in TNM stands for tumor, specifically tumor size. The T designation describes the size of the primary tumor and how far it has invaded surrounding tissue.


The N in TNM stands for nodes, or regional lymph nodes, which are usually the first place cancer spreads.

Lymph nodes are a key component of the immune system and function as the body's filtration system. As cancer cells break away from a tumor, they may travel through the lymphatic system, where some may survive long enough to take up residence in a lymph node and start a new tumor.


The M in TNM stands for metastasis, which occurs when the tumor has spread to parts of the body beyond the regional lymph nodes.

Colorectal cancer treatments by stage

Using the TNM categories and subcategories within each one, oncologists categorize each person's cancer using 0 and Roman numerals I through IV, with stage IV being the most advanced.

One caveat: These are just the broad stages or categories. Within each is a complex system of subgroups and subcategories that can wind up looking like alphabet soup to a layperson. Have your healthcare provider explain it in more detail if you have concerns.

Stage 0

Stage 0 colon cancer hasn't grown beyond the inner lining of the colon, so surgery to remove the lesion is usually sufficient. It can sometimes be removed with specialized endoscopic techniques using a colonoscope.

"The literature has changed as to whether you're supposed to call [stage 0] cancer or not," Hakimian said. "But these are lesions that are still superficial and don't go any deeper. You may be able to remove them with something called endoscopic mucosal resection [EMR] and endoscopic submucosal dissection [ESD]."

These types of procedures have become more common in recent years but are still only performed by a handful of gastroenterologists who have the necessary expertise.

Stage I

Colon cancer stage I has advanced into the colon wall's deeper layers but hasn't gone beyond the colon itself. It's usually treated with a partial colectomy, which is the removal of a section of the colon and removal of the regional lymph nodes.

"You'll remove part of the colon, including the blood vessels and lymphatics in that area that drain the region," Hakimian said. "Then the pathologist looks at the entire section, including the lymph nodes, to determine if there's local spread, if the cancer has spread to the deeper tissues or if it's isolated to just the surface of the colon."

While that sounds scary, the use of modern techniques and procedures usually produces positive outcomes for typical stage I colon cancer surgery.

"If it's more of a straightforward stage I-type cancer, most patients do very well with surgery," Hakimian said. "They stay in the hospital for a few days, and many times, [surgeons are] able to connect the remaining colon back together. Basically, they have very normal bowel function after."

Stage II

Stage II colon cancer has usually grown through the walls of the colon and possibly into the surrounding tissue but typically hasn't spread to the lymph nodes. A partial colectomy and removal of the nearby lymph nodes may or may not be the only treatment needed.

"If the patient has stage II or stage III, they may need more than surgery," Hakimian said. "They may need chemotherapy, as well, to treat the lesion better. A lot of that is patient-dependent. It depends on their health status and their goals, and becomes a discussion with an oncologist."

Stage III

At stage III, cancer has spread beyond the colon to nearby lymph nodes but typically not to other parts of the body. Standard treatment usually involves partial colectomy, removal of nearby lymph nodes and chemotherapy.

For some advanced cancers at this stage, neoadjuvant chemo (presurgery chemo) or radiation might be recommended to shrink the tumor before removing it surgically.

Stage IV

Stage IV is the gravest stage of cancer and indicates it has spread to distant parts of the body.

"Stage IV means that the cancer has metastasized," said Niket Sonpal, M.D., a gastroenterologist, internist and assistant professor at Touro College of Osteopathic Medicine in New York City. "So instead of doing surgery, they may put in a stent to open up the colon a little bit so the person doesn't get obstructed. Sometimes the person is too sick to tolerate surgery."

The strategy may sound counterintuitive, but a diagnosis of stage IV colon cancer often means no surgery will be recommended unless the spread—common places are the liver and lungs—is very isolated.

"With liver spread, occasionally if there's only a single lesion in the liver, surgery can still be considered," Hakimian said. "But if there's more widespread spread, then surgery might not be the right thing to do because you basically can't remove all the multiple metastases. So people undergo chemotherapy as their first mode of treatment."

Rectal cancer

Colon cancer is more common than rectal cancer, which represents about 30 percent of new colorectal cases each year.

The rectum, roughly the last 7 inches of the colon just before the anus, is subject to cancerous lesions. While the removal of one-third or even half of someone's colon may not affect their life much, the same doesn't always apply to rectal cancer surgery.

"Depending on the stage [of rectal cancer], on how deep that spread goes, sometimes the patient may need chemotherapy or radiation first before considering surgery," Hakimian said. "The surgery may have to be more complex."

An issue may arise when cancer spreads to the muscles that surround the lower part of the rectum. If they need to be removed, as well, the patient might not have the ability to control their stool after surgery, Hakimian said. This often means they need an ostomy procedure, which involves having their lower bowel surgically redirected to a stoma, an opening in their abdomen where waste passes into an attached pouch.


While a combination of surgery, chemo and possibly radiation is typically recommended depending on the type and extent of colorectal cancer, immunotherapy is an exciting, relatively new type of treatment that's advancing rapidly.

Immunotherapy takes advantage of the body's own defenses and the immune system's ability to attack only threatening cells while leaving healthy cells alone. Certain immune cells have proteins, or "checkpoints," that are turned on or off to determine whether to start an immune response.

Some colorectal cancer cells use these checkpoints to mimic healthy cells and avoid an attack. Immunotherapy drugs target these protein checkpoints to prompt the body's normal immune response to attack the cancerous cells.

"If patients have the right subtype of cancer, they may be candidates for some of these immunotherapies," Hakimian said. "And outcomes are better for patients than they were even 10 years ago when we didn't have these agents. Both the tolerance is better and the side effects are lower, the patients live longer and have fewer issues and complications."

Life after colorectal cancer

Keeping a close eye on the portion of the colon that remains after surgery is an important part of life after colorectal cancer treatment. Patients return to their gastroenterologist for checkups to make sure cancer hasn't returned.

"They'll get a colonoscopy one year after their surgery, where we'll surveil them for other polyps or colon cancers," Sonpal said. "Then they get a three-year colonoscopy, then five years."

If a patient does wind up with part of their colon resected, it's possible to return to life more or less as it was before.

"You don't actually need your colon to digest or to have a normal life," Hakimian said. "You can get away with removing a large part of your colon. The more colon you're missing, the less formed the stools are going to be, so you may have issues with diarrhea. But for the majority of colon cancer surgery, they don't remove the entire colon, just a segment of the colon, and people can have normal bowel movements afterward."


Nobody wants cancer. But at the end of the day, modern advances in surgical techniques, endoscopic procedures, precision chemo treatments and the new hope that immunotherapy offers make your chances of survival better than ever.

Even so, gastroenterologists want to remind everyone that avoiding all of those treatment options is still preferable and easy to achieve: get checked. Find out your family history of colon cancer, and even if there's no history at all, start getting screened at age 45.

Getting treated for a polyp with a simple snip during a routine colonoscopy is a lot easier to recover from than having a section of your colon removed. Even if the prognosis for recovery is better than ever before, you'd do well to avoid it if you can.

And you can.

"The number one thing is prevention and [it] is far better than having to go through the cure," Sonpal said. "As you can imagine, the cure involves massive surgeries, massive chemo, radiation and lifelong struggle, whereas a simple procedure early in life can prevent all that from happening, because 90 percent of all colon cancer is preventable."