The Society of Gynecologic Oncology (SGO) recently issued two new clinical practice statements recommending genetic testing for all women with endometrial and ovarian cancers, regardless of family history.
All women with ovarian, fallopian tube, or peritoneal cancer should receive genetic counseling and consider genetic testing regardless of age or family history, according to an SGO statement issued earlier this month. Taking a family history is not sufficient to assess risk of hereditary disease, the authors said, as nearly one-third of women with hereditary ovarian cancer have no close relatives with cancer.
“Careful pre-and post-test counseling is essential to understanding genetic testing options and results,” the SGO authors wrote. “Identification of hereditary cancer susceptibility allows for identification of cancer risk in other organs.”
Another practice statement advises all women diagnosed with endometrial cancer to undergo clinical and/or molecular screening for Lynch syndrome. Patients with Lynch syndrome, a hereditary cancer caused by a genetic mutation, have a 40% to 60% lifetime risk for endometrial and colon cancer.
“The identification of Lynch syndrome in women with endometrial cancer can lead to the prevention of a second cancer in the patient and incident cancers in family members through risk-reducing strategies and heightened surveillance,” the authors wrote.
Two main strategies are used to screen for Lynch syndrome in patients with endometrial cancer. A systematic clinical screening that includes a focused personal and family history can identify patients at high risk, who would then undergo germline or molecular tumor testing.
However, molecular tumor testing is the preferred strategy, the authors noted, because a significant percentage of women with Lynch syndrome do not have a suggestive family history.
The SGO statements also made the following points:
• BRCA1 and BRCA2 mutations account for approximately 15% of invasive ovarian cancers and lead to a 15% to 50% lifetime risk of ovarian cancer.
• Genetic test results can inform other family members about their risk of ovarian cancer, allowing those at high risk to consider more intensive screening or risk-reduction surgery.
• New therapies, such as PARP inhibitors, may lead to better treatment options for ovarian carcinoma associated with BRCA1 and BRCA2 mutations.
• All women with endometrial cancer diagnosed before age 60 should undergo immunohistochemistry—an inexpensive and widely available tumor study—to screen for expression of the four mismatch repair proteins that cause Lynch syndrome: MLH1, MSH2, MSH6, and PMS2. Other screening options include microsatellite instability analysis and MLH1 hypermethylation testing.