What are Polyps?
The lining of the digestive tract is in a state of constant repair where old cells die and are shed and new cells take their place. On occasion this renewal process creates an outgrowth of tissue referred to as a polyp that can extend out into the empty space within the stomach, small intestine, or colon. Mushroom shaped or pedunculated polyps have a narrow stalk that connects a ball shaped end to the intestinal wall. Flat or sessile polyps grow directly on the wall of the intestine. Polyps begin as small lumps that can grow over time to the size of a grape or larger.
When polyps are examined under the microscope, they can generally be divided into two groups:
- Hamartomas which are mushroom-like and called juvenile polyps
- Adenomas which can be either flat or mushroom-like
Juvenile polyps occur in children as single hamartomas that have a very low risk of long term problems. Adults can develop harmless juvenile polyps as well, but can also develop adenomas which are thought to represent the early stages of colon cancer. Adenomas can be found in children and indicate a need for further evaluation as described below. If an adenoma is removed, the cancer risk is eliminated. For this reason The National Cancer Institute suggests that all adults should undergo a screening examination of their colon, called a colonoscopy, beginning at the age of 50 to remove and study any polyps that may be present.
How Common are Polyps in Children?
A polyp of the colon or large intestine occurs in about 1-2% of children. The most common type of polyp in children is a hamartoma or juvenile polyp accounting for more than 95% of polyps found. Juvenile polyps are typically found in 2 to 6 year old boys and girls but can be found in younger and older children up to about 10 years of age. Most harmless polyps are single and are found in the bottom one third to one half of the colon.
Does My Child Have a Polyp?
Typically children with polyps will pass blood when they have a normal soft bowel movement that is not associated with pain or discomfort. Bleeding with the passage of stool tends to recur over weeks to months and may not happen with every bowel movement. With small amounts of bleeding over time, some children can develop iron-deficiency anemia and therefore have other symptoms including weakness, fatigue, pallor, or headache. On occasion, children can have other symptoms including crampy abdominal pain or diarrhea with mucus. At times, polyps can be seen by a parent after a bowel movement when they pass out of the anus still attached by a stalk to the colon wall and then go back into the rectum.
How are Polyps Diagnosed?
If a child presents with a visible polyp at the rectum, the diagnosis is easy to make. Most children who present with rectal bleeding that occurs with bowel movements are referred to a pediatric gastroenterologist. Your doctor will recommend a colonoscopy where the lining of the entire large intestine is examined with a narrow flexible instrument, called a colonoscope, mounted with a video camera and a light to help find the source of bleeding. When a polyp is found, the pediatric gastroenterologist will use a small grasping instrument called a snare that fits inside the colonoscope to remove and recovery the entire polyp. The polyp is then sent to the pathologist, who will look at it under the microscope to determine what kind it is. The gastroenterologist will look at the entire large intestine with the colonoscope to make sure that all polyps are found and removed. In special situations, polyps may be left behind especially if there are large numbers of polyps or removal could cause further problems such as uncontrollable bleeding.
What are the Potential Complications of Polyps?
The significance of juvenile polyps in most children is NOT the same as for adenomas in adults who are at increased risk of colon cancer. If a child is found to have a single juvenile polyp, he or she usually does not need to have a follow up colonoscopy because they have the same risk of colon cancer as the general population and should begin colon cancer screening in late adulthood at the age of 50. Colon polyps rarely lose significant amounts of blood unless they are pulled off the colon wall at their stalk by the normal movement of the colon. Larger polyps in the small intestine or colon can become a lead point allowing the bowel to telescope over itself creating a blockage called an intussusception. At times urgent surgery may be required to correct the intussusception and prevent further complications.
When are Further Studies Needed For My Child With Polyps?
The family history is important in any child who presents with a colon polyp. Some families pass on traits or genetic mistakes that lead to the growth of multiple polyps (inherited polyposis syndrome). In some of these hereditary polyposis disorders there is a family history of early colon cancer, or other serious cancers that can involve several generations. For most children, these disorders are inherited from a parent who has the same genetic disorder, yet may not have symptoms. Other children who lack a family history suggestive of a hereditary polyposis disorder may be the first in their family to acquire a gene mistake or mutation. Additional risk indicators include:
- A child with more than 5 juvenile polyps at first colon examination.
- The development of additional juvenile polyps after initial polyp removal.
- Polyps in the stomach or small intestine.
- One or multiple adenomas in a child or teenager.
In situations were a hereditary polyposis disorder is suspected, genetic counseling and testing can help to determine what syndrome is present and identify the gene mistake that may be present. If a specific mistake can be identified in the genetic code, it can be used to screen all members of that family to determine who is and who is not at risk. The gene mistake will not affect everyone within a given family in the same way allowing some to carry the mutation, and cancer risk, but not show the same symptoms, if any, that are seen in other affected family members. Genetic testing enables those at risk to receive the special care they need while avoiding unnecessary testing in those that do not carry the genetic mistake. Follow up care, known as surveillance, is designed to improve the duration and quality of life of patients with hereditary polyposis disorders through the early detection and treatment of complications that are known to occur with these diseases.