A polyposis genetic disorder with an onset in
adolescence presenting with gastrointestinal multiple colorectal adenomas
and primary central nervous system (CNS) tumors (e.g., supratentorial glioblastoma and
cerebellar medulloblastoma). Other clinical features include café-au-lait spots, cutaneous
port-wine stain, and focal nodular hyperplasia.
Glioma Polyposis; Familial Polyposis Coli.
Described by Jacques Turcot (b. 1914), a Canadian
An autosomal recessive inheritance has been
proposed for groups I and II (see Clinical Aspects below for a discussion of the groups).
However, in group III, an autosomal dominant inheritance is strongly
supported since this presentation is similar to the familial adenomatous
polyposis syndrome. In addition, germ-like mutations in the mismatch repair
gene hMLH1 or hPMS2 were found in some families. A mutation in the APC
(adenomatous polyposis coli) gene was reported.
The relative risk of cerebellar medulloblastoma in
patients with familial adenomatous polyposis is 92 times that of the general
population. Glioblastoma multiforme is also considered a frequent tumor in
association with this syndrome.
Based on clinical findings; in particular, the presence
of multiple adenomatous gastrointestinal polyps is associated with
neuroepithelial tumors of the CNS.
The Turcot Syndrome has been divided into three
groups based on the number and character of the colonic polyps. Group I
comprises patients with 20 to 100 polyps that are larger than 3 cm in
diameter. Malignant transformation usually occurs during the second and
third decade of life and occurs in all affected individuals. Group II
comprises patients with small polyps numbering fewer than 10, whereas Group
III comprises patients with innumerable small polyps, usually more than 100.
Gastrointestinal: Usually colonic polyps that may be fewer in number but larger than those
found in other familial polyposis syndromes. The polyps are frequently
associated with malignant transformation in the second or third decades.
Tumors of the stomach, duodenum, and small intestine have also been
described. CNS: neuroepithelial tumors—glioblastomas, medulloblastomas, and
astrocytomas. Ophthalmic: congenital hypertrophy of the retinal pigment epithelium.
Others: thyroid papillary carcinoma, café-au-lait spots.
Careful neurologic history to
exclude symptoms of CNS tumors. In the presence of central nervous tumor, an
assessment for raised intracranial pressure must be conducted, including an
eye examination, cell blood count, coagulation profile, and ABO cross-match must be
completed for important surgery. The radiological evaluation of all three
groups is identical to that of patients with familial adenomatous polyposis
Related to considerations for specific
type and site of CNS tumor. The presence of raised intracranial pressure will also
dictate the anesthetic technique. Implications associated with major intraabdominal
procedures must be applied.
There are no known specific
implications with this condition.
Gardner Syndrome: An autosomal dominant polyposis disorder
characterized by gastrointestinal adenomas, mostly colon and periampullary cancer.
Other clinical features include soft-tissue lesions, such as sebaceous cysts, fibromas,
leiomyomas, and lipomas, as well as bony lesions, such as multiple ...