What are the false positive rates for the OVA-1 (Ovarian Cancer Test)?

False Positive Rates for the OVA-1 Test

The NCCN does not recommend using the OVA-1 test due to concerns about false-positive results, though specific false-positive rates are not quantified in the available guidelines. 1

Guideline Position on OVA-1

The National Comprehensive Cancer Network explicitly states that the OVA-1 test should not be used for determining the status of an undiagnosed pelvic mass because:

• It increases cost without providing much benefit 1
• There are significant concerns about false-positive results 1
• The test is not approved as a screening tool for ovarian cancer 1

The NCCN recommends using ACOG/SGO clinical criteria instead, which rely on CA-125 levels, imaging characteristics, and clinical factors to determine whether referral to a gynecologic oncologist is warranted. 1

Context from Related Screening Tests

While specific false-positive rates for OVA-1 are not provided in the available evidence, the broader context of ovarian cancer screening demonstrates the magnitude of the false-positive problem:

CA-125 and Ultrasound Screening (PLCO Trial)

• Approximately 10% of screened women received false-positive results during the trial 1
• The positive predictive value was just over 1% across all screening rounds 1
• For every ovarian cancer detected, approximately 20 surgeries were performed 1
• Among women with false-positive results who underwent surgery, 15% experienced major complications 1

Population-Level Impact

• In average-risk women, the positive predictive value of screening is approximately 2%, meaning 98% of positive tests are false positives 2, 3
• False-positive results trigger additional invasive testing and potentially unnecessary surgery 2
• In one screening program, 3,285 women had false-positive results, with 1,080 (33%) undergoing surgery with oophorectomy 1

Clinical Implications

The high false-positive rate has serious consequences:

• Unnecessary anxiety in otherwise healthy women 2, 4
• Invasive follow-up procedures including laparotomy 5
• Surgical complications in women without cancer 1
• Increased healthcare costs without mortality benefit 1, 2

Recommended Alternative Approach

Use ACOG/SGO criteria for risk stratification: 1

For postmenopausal women, refer if:

• Elevated CA-125 (>35 U/mL) 1
• Nodular or fixed pelvic mass 1
• Metastatic disease or ascites 1
• Family history of breast or ovarian cancer 1

For premenopausal women, refer if:

• CA-125 >200 U/mL (some experts suggest >50 U/mL) 1
• Metastatic disease or ascites 1
• Strong family history of breast or ovarian cancer 1

Important Caveats

• The specificity of CA-125 alone is 98.5% in postmenopausal women but only 94.5% in premenopausal women 1
• False-positive CA-125 elevations occur with benign conditions including endometriosis, adenomyosis, pelvic inflammatory disease, menstruation, uterine fibroids, and benign cysts 1, 3
• Even with established screening methods, no mortality benefit has been demonstrated in average-risk populations 1