Neoplasms
Benign neoplasms
Autosomal recessive
2p16, 2p22-p21,3p21.3,7p22
Turcot syndrome is a rare, inherited, autosomal recessive disorder characterized clinically by the concurrence of a primary brain tumor and multiple colorectal adenomas. Symptoms associated with polyp formation may include bleeding from the end portion of the large intestine (rectum), diarrhea, fatigue, abdominal pain, and weight loss. Affected individuals may also experience neurological symptoms, depending upon the type, size and location of the associated brain tumor.
| Subject ID | Country | Sex | Family History | Parental Consanguinity | HPO Terms | Variant | Zygosity | Mode of Inheritance | Reference | Remarks |
|---|---|---|---|---|---|---|---|---|---|---|
| 276300.1.1 | Syria | Male | No | Yes | Rhabdomyosarcoma; Colon cancer Rhabdomyosarcoma; Colon cancer  | NM_000535.7:c.219T>A | Homozygous | Autosomal, Recessive | Al-Gazali and Ali, 2010 |
Soliman et al, 1998, conducted an Egyptian hospital-based pilot case-control study to investigate the relationship between the expression level of mismatch repair genes, hMSH2, hMLH1, hPMS1, hPMS2, and GTBP/hMSH6, and the risk of colorectal cancer. The study group included 31 colorectal cancer patients and 47 age- and-sex matched controls. The expression of hMSH2, GTBP/hMSH6, hPMS1 and hPMS2 tended to be lower in patients than controls, but only the difference in hPMS2 expression was statistically significant (p<0. 01).
Tan et al, 2008 studied a 15 year old girl and her 8 year old brother from a consanguineous Australian-Lebanese family affected by mismatch repair cancer syndrome. The girl was found to be homozygous for a deletion of exon 7 of the PMS2 gene.
Jamjoom et al, 1989, reported a case of Turcot syndrome in a 20-year-old man with multiple adenomatous polyps of the colon and glioblastoma multiforme. Detailed histopathological study of all 25 polyps removed from his colon confirmed the distinct morphological and numerical features of the colonic polyposis in Turcot syndrome. Almost half of the total polyps and all polyps with a diameter exceeding 2 cm showed malignant transformation, indicating the precancerous nature of these polyps.
Al Drees et al, 2000, described a 12-year-old female child with Turcot syndnrome. She presented a chronic bloody diarrhea and growth failure. Physical examination confirmed a growth failure and cafe-au-lait patches. Colonoscopy and colon biopsies showed adenocarcinoma of the colon and laparotomy confirmed metastases to the liver.