When should a woman with a family history of ovarian cancer in a first cousin be referred for genetic counseling?

Genetic Counseling Referral for Ovarian Cancer Risk

Direct Answer

A woman with only one first cousin who had ovarian cancer does NOT meet criteria for genetic counseling referral based on current guidelines. 1, 2

Specific Referral Criteria

You should refer a woman for genetic counseling when she has:

High-Priority Criteria (Always Refer)

• Two or more first- or second-degree relatives with ovarian cancer on the same side of the family 3, 4
• One first-degree relative (mother, sister, daughter) with ovarian, fallopian tube, or primary peritoneal cancer at any age 1, 2
• Combination of breast and ovarian cancer in first- or second-degree relatives on the same side of the family 3, 4
• Personal history of epithelial ovarian, tubal, or peritoneal cancer (regardless of family history) 1

Special Population Criteria

• Ashkenazi Jewish ancestry with one first-degree relative OR two second-degree relatives on the same side with breast or ovarian cancer 3

Why Your Patient Doesn't Qualify

A first cousin is a third-degree relative, not a first- or second-degree relative. 1 The guidelines specifically require:

• First-degree relatives: mother, sister, daughter
• Second-degree relatives: grandmother, aunt, half-sister
• First cousins do not meet the threshold for referral 3, 2

What to Do Instead

Educate about risk-reducing factors rather than pursuing screening or genetic testing: 3

• Oral contraceptive use reduces ovarian cancer risk by approximately 50% 3
• Pregnancy, breastfeeding, and bilateral tubal ligation also reduce risk 3
• Do NOT order CA-125 or transvaginal ultrasound screening - the USPSTF gives a Grade D recommendation (harms outweigh benefits) against ovarian cancer screening even in women with family history 3, 4

Critical Pitfall to Avoid

Never order ovarian cancer screening tests (CA-125, transvaginal ultrasound) for women with family history alone. 3, 4 The PLCO trial of 78,216 women (17% with family history) showed no reduction in ovarian cancer deaths with screening, but approximately 10% received false-positive results leading to unnecessary surgeries with a 20:1 ratio of surgeries to screen-detected cancers. 3

When to Reassess

Update family history every 5-10 years to identify changes that might meet referral criteria, such as additional relatives developing ovarian or breast cancer. 1