What are the other Names for this Condition? (Also known as/Synonyms)

• Sessile Serrated Adenomas (SSA) of the Colon
• SSA (Sessile Serrated Adenomas) of the Colon
• SSP (Sessile Serrated Polyps) of the Colon

What is Sessile Serrated Polyps of the Colon? (Definition/Background Information)

• Colon polyps are extra cells that clump and grow on the lining of the colon or rectum. It is a benign condition that occurs due to abnormal cell growth within the colon tissue
• There are multiple types of colon polyps, namely:
  • Hyperplastic Polyp of Colon:
  • Inflammatory Polyp of Colon:
  • Adenomatous Colon Polyp:
  • Serrated Colon Polyp:
• Sessile Serrated Polyps (SSPs) of the Colon are benign tumors that can develop into colorectal cancers if left untreated, similar to conventional adenomas of the colon. Conventional adenomas are typically tubular adenomas, tubulovillous adenomas, and villous adenomas
• Sessile Serrated Polyps of the Colon are thought to arise as a result of a series of genetic mutations, which is different from the ones found in conventional adenomas and adenocarcinomas (which arise from convention adenomas)
• The series of genetic mutations giving rise to ‘Sessile Serrated Polyp’ and ‘Sessile Serrated Polyp - derived Cancers’ is referred to by some researchers as the “serrated neoplasia pathway”
• Sessile Serrated Polyps of the Colon are considered premalignant tumors. This means that these tumors may turn malignant with time. A complete removal of the polyps can result in a cure

Who gets Sessile Serrated Polyps of the Colon? (Age and Sex Distribution)

• Individuals with Sessile Serrated Polyps of the Colon are usually older adults, with a mean age at diagnosis of 65 years
• Both males and females can get these benign tumors; no gender predilection is observed
• No ethnic or geographical predisposition is noted

What are the Risk Factors for Sessile Serrated Polyps of the Colon? (Predisposing Factors)

Risk factors for Sessile Serrated Polyps of the Colon include:

• Having other serrated lesions/polyps including other sessile serrated polyps, traditional serrated adenomas, and hyperplastic polyps (occurring on the right portion of the colon)
• Individuals with genetic mutations involved in the so called “serrated neoplasia pathway” are also more likely to developing SSPs

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Sessile Serrated Polyps of the Colon? (Etiology)

Sessile Serrated Polyps of the Colon is caused by genetic mutations that results in dysplasia.

• Dysplasia is the phenomena of disordered growth of the epithelial lining of the colon. Genetic mutations lead to cell growths at abnormally high rates. This causes the cells to grow abnormally, forming the tumors characteristic of a sessile serrated polyp
• The genetic mutations can be either inherited, or caused by exposure to various environmental factors
  • Inherited genetic mutations have been documented
  • Environmental factors that cause genetic mutations may include radiation, harmful chemicals in the air, etc.
• Characterizing the genetic mutations in SSPs of the Colon and other serrated lesions/polyps, are still a subject of ongoing research

What are the Signs and Symptoms of Sessile Serrated Polyps of the Colon?

Most individuals with Sessile Serrated Polyp of the Colon do not show any signs and symptoms. Typically, individuals do not notice that they have a polyp, until these are visualized during a screening colonoscopy.

In rare cases, the signs and symptoms of Sessile Serrated Polyp of the Colon may include: 

• Tumor in the colon causing obstructions (if the tumors are large)
• Bleeding from the anus or mucus mixed with stools; both occur only in rare cases
• Rarely, diarrhea or constipation

Most Sessile Serrated Polyps are small and therefore asymptomatic.

How is Sessile Serrated Polyps of the Colon Diagnosed?

Diagnosis of Sessile Serrated Polyp of the Colon is normally established by:

• A thorough medical history and complete physical examination
• A family history of colon cancer and prior colonoscopy findings (if any), are very important considerations
• Typically, Serrated Colon Polyps are first diagnosed during a colonoscopy screening:
  • During this procedure, a thin, flexible tube (called a colonoscope) with a video camera attached to it, is inserted into the body to view the colon and rectum
  • If a polyp is present, a projection will appear on the screen that originates from the epithelial lining of the colon
  • During the colonoscopy, the tumor (polyp) is removed and submitted to a pathologist for examination. The pathologist establishes the diagnosis by examining the tissue under the microscope

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Sessile Serrated Polyps of the Colon?

The possible complications of Sessile Serrated Polyps of the Colon could include:

• Sessile Serrated Polyps of the Colon are premalignant neoplasms, meaning that they can lead to the development of colorectal cancers, if left untreated, or they are removed incompletely. This is a life-threatening condition, if not detected and treated. However, the process of a sessile serrated polyp becoming a cancer may take many years
• Individuals with SSPs tend to have other “serrated” polyps (other SSPs, hyperplastic polyps, and traditional serrated adenomas). Hence, such individuals need to be screened more frequently for cancer, as against individuals with conventional adenomas (such as tubular adenomas, tubulovillous adenomas, and villous adenoma)

How is Sessile Serrated Polyps of the Colon Treated?

Sessile Serrated Polyps are currently best treated in a manner analogous/comparable to the treatment of conventional adenomas (such as tubular adenomas, tubulovillous adenomas, and villous adenoma).

• A complete removal of the benign tumor as early as possible, is ideal
• However, because they are “sessile” (flat-based), it is often difficult to remove them using colonoscopy alone. Therefore, sometimes a surgical removal (with removal of a colon segment) may be required
• The gastroenterologist will remove the tumor via a polypectomy, or ablate the tumor using heat
• If residual tumor remains in the colon after removal, another colonoscopy may be required, in order to completely remove the growth
• If the tumor has grown too large to be removed via a polypectomy, a surgery may be required to remove a part of the colon. This is called a segmental colectomy. This involves incising the abdomen so that the colon can be reached

How can Sessile Serrated Polyps of the Colon be Prevented?

Currently, there are no known preventative measures against Sessile Serrated Polyps of the Colon. 

• It is important to undergo routine colonoscopy screenings as you get older (over the age of 45-50 years), to ensure that no tumors or polyps develop
• Precautions may also be taken against environmental harms that can cause the polyp. It is helpful to limit one’s exposure to environmental toxins and radiation

What is the Prognosis of Sessile Serrated Polyps of the Colon? (Outcomes/Resolutions)

• With complete removal and adequate follow-up, the prognosis of an individual with Sessile Serrated Polyp of the Colon, is good. It does not develop into cancer
• However, if cancer is found within a Sessile Serrated Polyp, then the prognosis cannot be predicted; the condition can become life-threatening. In such cases, the prognosis depends on the stage of the cancer

Additional and Relevant Useful Information for Sessile Serrated Polyps of the Colon:

Note:  The nomenclature of Serrated Polyps is a matter of great confusion, even among specialists. Sessile Serrated Polyps are sometimes called “serrated adenomas”, even by physicians; which is incorrect. What have been traditionally called serrated adenomas by researchers, have been reclassified as “traditional serrated adenomas” (TSA), to distinguish them from Sessile Serrated Polyps.

• Traditionally, polyps in the colon were divided into either tubular adenomas (which can develop into colorectal cancers, needed to be removed completely and followed closely) or hyperplastic polyps (benign, clinically insignificant lesions that require no treatment)
• With the discovery and characterization of Sessile Serrated Polyps, the subject of polyps in the colon has become somewhat more complex, especially because SSPs often microscopically resemble hyperplastic polyps

Information for a pathologist:

• The pathologic features of Sessile Serrated Polyps of the Colon include serrated colonic mucosa with focal areas resembling the histologic appearance of hyperplastic polyps
• However, unlike hyperplastic polyps, the serrations in SSPs extend all the way to the base of the crypts, with lateral “branches”, which are sometimes referred to as “bootlegging” or “duck feet”
• Additionally, SSPs tend to be more frequently right-sided (as opposed to hyperplastic polyps, which are usually left-sided) and SSPs are usually larger than hyperplastic polyps
• The distinction is important because, as stated above, although SSPs resemble hyperplastic polyps microscopically, their clinical course (the increased risk of developing cancer that they confer to patients) more closely resembles that of conventional colonic adenomas
• However, sometimes, this distinction is difficult or even impossible. Recent research is still working towards better means of identifying these lesions with precision