A Polyp for Your Thoughts

 

 

A friend of mine had a colonoscopy recently.

“Did they find anything?” I asked him.

“They found a couple of polyps,” he said, “but they weren’t those cancerous ones.”

“What do you mean, they weren’t those cancerous ones?” I asked, being a pathologist, after all. “Were they hyperplastic or adenomatous?”

Naturally, his eyes glazed over and he just shrugged. 

“What did your doctor tell you they were?” I persisted.

“He just said they weren’t cancerous.”

“When did he say you should have another colonoscopy?”

“Two years from now.”

OK. What we have here is a failure to communicate. The vast majority of polyps aren’t cancerous. But there are some that can become cancerous, and some that never do, no matter how big they get.

The mere fact that my friend was advised to have another colonoscopy in two years told me that his polyps were the kind that can become cancerous. Otherwise, he wouldn’t have to have another colonoscopy for ten years.

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The majority of colon polyps fall into two categories: hyperplastic (top) and adenomatous (bottom). There are a few other kinds of polyps, but these are the most common. Hyperplastic polyps have 0% risk of cancer. Adenomatous polyps have a 10% cancer risk, and the bigger they get, the bigger the risk.

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The first change in an adenomatous polyp is called high-grade dysplasia (above). It’s a premalignant change. If a polyp can be removed, and the dysplastic area is completely surrounded by benign colonic mucosa, that’s all that needs to be done.

But sometimes the dysplastic mucosa covers the stalk of the polyp.

Sometimes the dysplastic changes invade into the stalk of the polyp. That’s cancer.

When that happens, the patient must have a colon resection to be sure all the malignant tissue is gone, and that none of the cancer has involved lymph nodes. Usually a cancer that early hasn’t involved anything but the area right around the polyp.

What about my friend?

Well, I guess he’ll have to wait until his next colonoscopy, two years from now.

For right now, he doesn’t have cancer, and I guess that’s all he needs to know

Big Juicy Colons

Since the name of this blog is bigjuicycolon.com, I figured we may as well start with colon cancer. That and diverticulitis are the usual reasons colons get removed. Not the entire colon, mind you, just the affected part. It may look like the surgeon took more than he needed to, but surgeons have to be mindful of the vascular supply to the remaining colon. Everything that has the same vascular supply as the affected part has to be removed, or it will become gangrenous, and that will require another surgery.

colon cancer

colon cancer

Ever since Katie Couric’s husband Jay died of colon cancer at age 42, colon cancer has been pretty much out of the closet.  Colon cancer is one of the commonest cancers in this country, after lung and breast. Most colon cancers look pretty much like this. 

The surgeon needs to know that the margin is adequate. That’s why fresh colon resections come to pathology so that the pathologist can open them and measure how far the tumor is from the ends of the specimen. Especially when there is more than one tumor, which can happen. Here’s a colon with three!

colon w 3 cancers

And one of them is right in the margin.

Some specimens are pretty striking. Patients who use certain kinds of laxatives for years get this dark brown coloration of the mucosa, called melanosis. Notice that the small bowel, the polyps, and the cancer are not colored. That’s because they grow fast and don’t have enough time to get discolored.

colon with melanosis, a cancer, and polyps

colon with melanosis, a cancer, and polyps

Colon cancers nearly always start from polyps, also called adenomas. Here is an example of an adenoma.

colon polyp

colon polyp

Ever wonder what pathologists see when they look through the microscope? This slide shows the microscopic appearance of normal colon mucosa, or lining.

normal colon mucosa

normal colon mucosa

This slide shows cancer arising in an adenoma. Adenoma on the left, cancer on the right.

adenoma-carcinoma spectrum

adenoma-carcinoma spectrum

This is cancer too.

colon cancer micro

colon cancer micro

What do you think? Grossed out? I did warn you, you know. Me, I find this stuff fascinating.

Guess I wouldn’t be a pathologist if I didn’t.

Now, what do you want to see next?