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MUTYH Polyposis Syndrome


Anthony Villano

, MD, Fox Chase Cancer Center

Reviewed/Revised Oct 2023

MUTYH polyposis syndrome is a rare autosomal recessive disorder responsible for < 1% of colorectal cancer. Manifestations are similar to other forms of colorectal polyps or cancer. Diagnosis is by genetic testing. Patients should have surveillance colonoscopy and screening for other cancers, particularly gastroduodenal, thyroid, bladder, ovarian, and skin. Treatment is endoscopic removal or sometimes surgery.

In addition to colon cancer, affected individuals are at increased risk of gastroduodenal adenomas, osteomas, desmoid tumors, Muir-Torre phenotype with sebaceous gland tumors, and congenital hypertrophy of the retinal pigment epithelium (a feature also occurring in patients with familial adenomatous polyposis Familial Adenomatous Polyposis Familial adenomatous polyposis is a hereditary disorder causing numerous colonic polyps and frequently results in colon carcinoma, often by age 40. Patients are usually asymptomatic but may... read more Familial Adenomatous Polyposis ). Affected individuals are also at risk of developing cancer of the ovary, bladder, thyroid, and skin.

General references

  • 1. Sieber OM, Lipton L, Crabtree M, et al: Multiple colorectal adenomas, classic adenomatous polyposis, and germ-line mutations in MYH. N Engl J Med 348:791–799, 2003. doi: 10.1056/NEJMoa025283

  • 2. Cleary SP, Cotterchio M, Jenkins MA, et al: Germline MutY human homologue mutations and colorectal cancer: A multisite case-control study. Gastroenterology 136(4):1251-1260, 2009. doi: 10.1053/j.gastro.2008.12.050

Diagnosis of MUTYH Polyposis Syndrome

  • Genetic testing

Genetic testing is required to establish the diagnosis.

Testing the spouse of an affected patient for the MUTYH gene may be cost-effective; if the spouse is heterozygous, their children should then have genetic testing for this disorder.


Affected patients should have surveillance colonoscopy every 1 to 2 years starting at age 25 to 30. They should have upper endoscopy starting at age 30 to 35. The frequency of this test depends on the presence of gastroduodenal polyps. Fundic gland polyps should be biopsied for dysplasia.

Annual thyroid screening with physical examination and ultrasonography is also recommended. Patients also frequently undergo surveillance for ovarian, bladder, and skin cancers; however, no consensus guidelines exist to guide the specific frequency.

Monoallelic carriers are screened for colorectal cancer with colonoscopy every 5 years beginning at age 40 (similar to a person who has a first-degree relative with colorectal cancer).

Treatment of MUTYH Polyposis Syndrome

  • Endoscopic removal

  • Sometimes surgical resection

Endoscopic management (eg, polypectomy, mucosal resection) is the main treatment of MUTYH polyposis syndrome.

If cancer is present or the polyp burden is too large, surgical resection is needed. Partial, subtotal, or total colectomy are the surgical options, depending on the extent and burden of disease.

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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