Turcot Syndrome: Causes, Symptoms, Treatment, Diagnosis
What is Turcot Syndrome?
Turcot Syndrome is an extremely rare inherited pathological condition which is characterized by development of numerous adenomatous polyps along the mucous lining of the gastrointestinal tract. These polyps are benign. In some cases there may also be development of tumors within the nervous system.
As a result of these polyps, the affected individual may experience numerous gastrointestinal symptoms like diarrhea, rectal bleeding, lethargy and persistent fatigue, pain in the abdominal area and unintentional weight loss. If the nervous system is also involved with a tumor present in the brain then the affected individual may also experience certain neurological symptoms along with persistent headache.
Studies have suggested that Turcot Syndrome is nothing but a form of Familial Adenomatous Polyposis. What exactly causes these polyps to develop is something which is still a matter of study and is not known. The treatment for the most part is surgical for majority of cases of Turcot Syndrome.
What are the Causes of Turcot Syndrome?
As stated the exact cause of Turcot Syndrome is not known. According to studies, Turcot Syndrome has been divided into two parts which are Type I and Type II. This division is based on the number of polyps present.
If the polyps are few and less than 100 then it falls in Type I Turcot Syndrome whereas if the number of polyps is greater than 100 then it falls in Type II of Turcot Syndrome.
Studies also suggest that Type I of Turcot Syndrome follows an autosomal recessive pattern of inheritance whereas Type II of Turcot Syndrome follows an autosomal dominant pattern of inheritance.
The gene responsible for Type I Turcot Syndrome is the MLH1 and PMS2 gene. The function of these genes is to repair damaged DNA. Type II Turcot Syndrome is caused by the mutations in the APC gene. The function of this gene is to suppress tumor progression and mutation in this gene results in tumor progression seen with Turcot Syndrome.
What are the Symptoms of Turcot Syndrome?
The classic presenting feature of Turcot Syndrome is the presence of numerous polyps along the mucosal lining of the gastrointestinal tract. It is sometimes associated with a tumor in the brain.
As a result of these polyps, the affected individual experiences rectal bleeding, alternating diarrhea and constipation. Pain in the abdomen is yet another symptom along with unintentional weight loss for Turcot Syndrome.
Type I Turcot Syndrome has less than 100 polyps present where as if the number of polyps is greater than 100 then it falls into type II of Turcot Syndrome.
The size of the polyps in type I Turcot Syndrome is far more than those in type II Turcot Syndrome and hence the chances of these polyps becoming malignant are more in Turcot Syndrome.
How is Turcot Syndrome Diagnosed?
To confirm a diagnosis of Turcot Syndrome the treating physician will first take a detailed history of the patient inquiring about the symptoms and the duration and severity of it.
A detailed abdominal examination is then conducted along with radiological images of the gastrointestinal tract which will clearly show the presence of polyps and confirm the diagnosis of Turcot Syndrome.
In case if an individual has a known diagnosis of Turcot Syndrome then the chances of his or her child also developing this condition is quite high and thus it is highly recommended that such children undergo routine screenings through sigmoidoscopy to confirm the presence of any polyps for an early detection of the development of Turcot Syndrome.
Genetic testing will then be done which will clearly show mutations in the genes responsible for causing this condition and thus confirm the diagnosis of Turcot Syndrome. Additionally, diagnostic testing in the form of colonoscopy and rectal tissue biopsy is also quite helpful in confirming the diagnosis of Turcot Syndrome.
How is Turcot Syndrome Treated?
The treatment of Turcot Syndrome is basically symptomatic. Surgically removing the large intestine and the rectum may prevent the risk of the polyps getting malignant. This is highly recommended for patients with Type I of Turcot Syndrome.
There is yet another procedure in which the large intestine is removed and the rectum is attached to the small intestine. This approach towards treatment has been shown to be more potent and results in significant regression of rectal polyps formed due to Turcot Syndrome. Hence, this form of treatment is highly recommended by healthcare professionals but after the procedure the patient must be screened routinely through sigmoidoscopy for development of any new polyps and if present then immediate correction of it so as to treat the patient with Turcot Syndrome.
In cases where the number of polyps is far more and their growth is rapid then the rectum may have to be removed and the small intestine may be connected to the abdominal wall. This procedure is called as ileostomy and is also quite a good alternative treatment for Turcot Syndrome.
Periodic neurological screenings is also recommended for individuals with Turcot Syndrome to check for presence of any brain tumor and if detected treatment should be begun for it as well.
Brain tumor may require surgery for removal of the tumor depending on the location and size of the tumor. This is a complex surgery as the tumor needs to be removed as much as possible without causing any harm to the surrounding structures. The surgery will then be followed by radiation and chemotherapy to complete the treatment for brain tumor caused by Turcot Syndrome.