Term
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Definition
| A condition characterized by the presence of numerous internal polyps which may become malignant. |
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Term
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Definition
| A condition that is still a hereditary cancer syndrome, but is not characterized by an abundance of internal polyps. |
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Term
| What are some risk factors for colorectal cancer? |
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Definition
Aging
Personal or family history of colorectal cancer
diet
inflammatory bowel disease
hereditary colon cancer syndromes |
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Term
| What are the stages of a malignant polyp? |
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Definition
A polyp starts as a benign hyperproliferation of tissue. It grows into what is called an adenomatous polyp -- these polyps start small and then grow into a dysplastic, precancerous stage.
The polyp then turns to an adenocarcinoma, which is malignant. However, it is only truly a cancer when it has invaded the surrounding tissue.
This process takes about 10 years |
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Term
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Definition
A precancerous polyp. These polyps start as hyperproliferation and grow to become dysplastic.
They are still considered benign at this point. Fewer than 10% of adenomatous polyps continue to grow into cancer. |
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Term
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Definition
A polyp (an adenomatous polyp) that has become very dysplastic and malignant.
It is considered malignant, but is not considered a true cancer until it invades the surrounding tissue. |
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Term
| What are the four main parts of the colon? |
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Definition
| The ascending colon, where the small intestine meets the colon (ascending up through the body), the transverse colon, the descending colon (going back down on the left) and the sigmoid colon (the very end of the colon) |
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Term
| What are the three types of rarely malignant polyps? |
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Definition
| Hyperplastic, inflammatory, and hamartomatous |
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Term
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Definition
| The most common type of polyp. Rarely malignant. |
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Term
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Definition
| One of the rarely malignant polyp types. However, they are often seen in juvenile polyps and Peutz-Jeghers syndrome. |
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Term
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Definition
| A polyp that has a flat base that attaches to the colon. Harder to remove -- has to be “scooped” out. |
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Term
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Definition
| A polyp that sits on a “stem.” You can snip the stem to remove it from the colon. |
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Term
| Adenomatous polyps can be classified in three ways: |
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Definition
Tubular: The most common and occur anywhere
Tubulovillous: most often occur in the rectum
Villous: high morbidity and mortality rates.
You don't have to know these in great detail just know that a tubular polyp on a report would be an adenamatous polyp. |
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Term
| Familial Adenomatous Polyposis (FAP) |
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Definition
The penetrance for adenomas for people with this condition is 100%. “Carpeted” with polyps. Autosomal dominant.
High colon cancer risk if polyps not dealt with. Also have a risk of other GI cancers, thyroid, and brain cancers.
One clinical sign of this syndrome is CHRPE.
Management is to do a sigmoidoscopy from age 10 until polyps develop, then switch to colonoscopy to remove. Might get a colectomy. |
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Term
| What is the inheritance pattern of familial adenomatous polyposis (FAP)? |
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Definition
| Autosomal dominant, but 25% of mutations are de novo. Caused by APC tumor suppressor gene. Most families have unique mutations. |
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Term
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Definition
A subtype of FAP. It is later onset and there are fewer adenomatous polyps.
It is also not associated with CHRPE. Makes up 10% of FAP.
Tend to have mutations at end of the APC gene or a complete deletion. They tend to get about 30 adenomatous polyps. Management is colonoscopy every 2-3 years. |
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Term
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Definition
A variant of FAP. They have the features of FAP (including CHRPE) plus extraintestinal lesions.
They get desmoid tumors (tumors from the soft tissue), osteomas (jaw bone tumors), and skin tumors.
They also tend to have extra teeth. |
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Term
| Congenital Hypertrophy of the Retinal Pigment Epithelium (CHRPE) |
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Definition
| A pigmented lesion on the retina. Does not interfere with vision, but can be a marker for familial adenomatous polyposis (FAP). |
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Term
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Definition
A founder mutation of the Ashkenazi Jews (about 6%).
It creases a hypermutable area in the APC gene (the one associated with FAP). It causes a 2-fold increases in colorectal cancer risk, but it’s phenotype is the same as sporadic colorectal cancer. Does not look like other FAP. |
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Term
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Definition
| A colonoscopy that only looks at the descending colon and sigmoid colon. |
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Term
| MUTYH-Associated Polyposis (MAP) |
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Definition
Not as many polyps as FAP, but between 15 and 100. Many are adenomatous and some are hyperplastic. Autosomal recessive.
Two common mutations but over 80 are reported. Carriers have a 2-fold risk of colorectal cancer, but there are no specific screening recommendations. |
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Term
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Definition
A rare hereditary cancer syndrome. Causes adenomatous polyps and primary brain tumors.
Usually described as dominant, sometimes described as recessive.
Can be caused by an APC mutations (FAP).
This is associated with medulloblastomas (brain cancer). Can also be caused by PSM2/MLH1 (Lynch) mutations, which is associated with glioblastomas (another brain cancer). |
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Term
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Definition
A hamartomatous polyp condition (more risk than hyperplastic, less than adenomatous). Autosomal dominant.
Genes are Smad4 and BMPRIA.
It is considered Juvenile Polyposis if you have 5 juvenile polyps, polyps throughout the GI tract, or a family history of juvenile polyposis.
50 fold increase in colon cancer risk and an increase in GI cancer risk. Can be associated with Hereditary hemorrhagic telangiectasia (HHT). |
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Term
| Peutz-Jeghers Syndrome (colon) |
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Definition
A hamartomatous polyp condition (more risk than hyperplastic, less than adenomatous). Autosomal dominant.
Remember, this is the breast cancer syndrome that has the characteristic lip pigmentation that looks like blue ink. As well as being a breast cancer risk factor, Peutz-Jegher Syndrome can also cause GI cancers and a moderate amount of (less than 100) hamartomatous polyps. By 20 half of patients have symptoms such as GI bleeding, abdominal pain, and obstruction. Also associated with intussusception. |
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Term
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Definition
| A feature associated with Peutz-Jeghers Syndrome. It is when the small intestine becomes folded over (like a telescope that folds in). |
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Term
| PTEN Hamartoma Tumor Syndrome (aka Cowden) (colon) |
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Definition
Considered a hamartomatous polyp condition (more risk than hyperplastic, less than adenomatous).
High risk of GI polyps of various kinds, an increased risk for colon cancer (about 9%). |
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Term
| Hereditary Mixed Polyposis Syndrome |
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Definition
| Increased risk of colon cancer due to a variety of polyp types including juvenile polyps (hamartomas), adenomatous polyps, hyperplastic polyps, inflammatory polyps, and more. Autosomal dominant inheritance. |
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Term
| Sessile Serrated Polyposis Syndrome |
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Definition
| Sessile (flat) polyps that have a “serrated” look to them. To be diagnosed these people need large polyps (two larger than 10 mm), a family history, or many polyps (more than 20). |
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Term
| Oligodontia-colorectal cancer syndrome |
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Definition
Autosomal dominant syndrome.
A various number of adenomatous polyps. Also characterised by missing adult teeth. Can also have abnormal sweating and sparse hair. |
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Term
| Lynch Syndrome (AKA Hereditary non-polyposis colorectal cancer, HNPCC) |
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Definition
Autosomal dominant. Usually MLH1 and MSH2, sometimes MSH6 or PMS2 or EPCAM.
Does have some polyps but not as many. Often early age of colorectal cancers (ie, under 45) and on the right side.
Also involved other cancers such as endometrial, ovary, stomach, urinary tract, small bowel, skin, brain, etc. Often get multiple cancers.
Look for colon and endometrial -- these are indicative of lynch syndrome.
Colonoscopies are so good colectomy is not recommended until the first cancer appears. |
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Term
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Definition
A variant of Lynch syndrome. Associated with the MSH2 and MLH1 genes.
Has dermatological features. Sebaceous gland tumors on the face and scalp and tumors from hair follicles. |
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Term
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Definition
| This rule helps you decide if someone should be tested for Lynch syndrome. At least three relatives with Lynch-associated cancers. At least 2 generations affected. One or more cancers before age 50. (Exclude people with FAP) |
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Term
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Definition
| Include microsatellite instability studies (looking at unstable regions) and immunohistochemistry (staining for proteins). Everyone that has colon cancer should have a tumor study because it increases the survivability of relatives. |
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Term
| Constitutional Mismatch Repair Deficiency (CMMR-D) |
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Definition
A brain tumor and polyposis syndrome. Features include early onset colon cancer, leukemia, childhood brain tumors, and cafe au lait macules.
Autosomal recessive. Cuased by mutations in both lynch syndrome genes (PMS2 usually). |
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