Comprehensive COLARIS^® or MSH6 Analysis
POSITIVE FOR A DELETERIOUS MUTATION

A positive for a deleterious mutation test result means that a deleterious mutation was found in either the MLH1, MSH2 or MSH6 gene, indicating an increased risk for cancers associated with hereditary nonpolyposis colorectal cancer (HNPCC). If your patient has already been diagnosed with cancer, a positive for a deleterious mutation result indicates an increased risk for a second primary cancer. Click here to a view a list of published estimates of cancer risks for HNPCC mutation carriers.

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COLARIS^® Positive for a Deleterious Mutation or Suspected Deleterious

A positive for a deleterious mutation result allows you to personalize your patient's medical management and enables other family members to determine whether they have also inherited the same cancer-susceptibility mutation.

Medical Management Recommendations

The following procedures are recommended to reduce morbidity and mortality in patients who test positive for an HNPCC gene mutation:

COLORECTAL CANCER

Surveillance

• Colonoscopy every 1-2 years, beginning at age 20-25. Colonoscopy annually after age 40.

Surgical Management

• If colorectal cancer (or more than one advanced adenoma) is diagnosed in a patient with HNPCC, colectomy with ileorectal anastomosis or hemicolectomy are the recommended surgical options, rather than segmental colectomy.

• Prophylactic colectomy with ileorectal anastomosis is an option for known HNPCC patients who are unable/unwilling to undergo frequent colonoscopies.

ENDOMETRIAL CANCER

Surveillance

• Gynecologic exam, transvaginal ultrasound, endometrial aspiration, and CA-125 every 1-2 years, beginning at age 25-35.

Surgical Management

• Total abdominal hysterectomy and bilateral salpingo-oophorectomy may be considered if colorectal cancer is detected and may also be considered as an option when childbearing is concluded (especially if bleeding or other symptoms of uterine or ovarian disease occur).

EXTRA-COLONIC CANCER

Surveillance

• Screening for other HNPCC-related cancers (gastric, ureter/renal pelvis, biliary tract, small bowel, pancreas, brain) may be considered.

Implications for Family Members

Once a mutation has been detected in a family, other family members can be tested for the specific family mutation. Since mutations in this gene are inherited in an autosomal recessive pattern, first-degree relatives are at 50% risk to carry the same mutation. Those family members testing positive for the known mutation are managed more aggressively in order to detect cancer early and sometimes even prevent cancer. By contrast, individuals who did not inherit the family mutation are not at increased risk for cancer and may adhere to general population screening guidelines, as long as there is no independent history of cancer on the other side of the family.

First-degree relatives include an individual's parents, siblings, and children. Click here for a pedigree that indicates which family members are first-degree, second-degree, and third-degree relatives. Other more distant family members, such as nieces, nephews, aunts, uncles, and cousins, may also be at risk for the same gene mutation found in your patient. In order to determine which side of the patient's family carries the mutation, the parents may have Single Site COLARIS^® to determine their mutation status. For some patients, it may be possible to assume which side of the family is at risk, based on the history of cancer in the family. If possible, the suspected parent's carrier status should be confirmed through genetic testing. It is important to remind patients about the importance of sharing their genetic information with at-risk family members.

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