Ovarian cancer is often referred to as a silent disease because its symptoms are vague, making early detection a significant challenge. By the time the disease is discovered, it has frequently progressed to an advanced stage, which complicates treatment and reduces survival rates. The Risk of Ovarian Malignancy Algorithm (ROMA) was developed to help medical professionals assess the nature of a pelvic mass before surgery. This tool numerically estimates the likelihood that an adnexal mass is cancerous rather than benign. The ROMA test combines the results of two specific blood protein markers with the patient’s menopausal status to produce a single, actionable score that assists in deciding whether a patient should be referred to a specialized gynecologic oncologist.
Biomarkers Measured by ROMA
The ROMA calculation measures the concentration of two distinct proteins circulating in the patient’s blood: Cancer Antigen 125 (CA-125) and Human Epididymis Protein 4 (HE4). Both are serum biomarkers whose levels can increase in response to a developing malignancy. CA-125 is the older marker, historically used to monitor ovarian cancer progression. However, CA-125 lacks specificity because its levels can also rise due to various benign conditions, such as endometriosis, pelvic inflammatory disease, or menstruation.
The inclusion of HE4 significantly improved the algorithm’s accuracy. HE4 is a newer marker overexpressed in most epithelial ovarian cancers. Importantly, HE4 is less affected by the benign gynecologic conditions that often cause false elevations in CA-125 levels. Measuring both markers simultaneously provides a more comprehensive picture than relying on either one alone.
The biomarkers are measured using an immunoassay blood test, which quantifies the exact concentration of each protein. The raw values for CA-125 (U/mL) and HE4 (pmol/L) are then input into the mathematical algorithm. This combination mitigates the weaknesses of each individual marker, offering a refined assessment of malignancy probability.
How Menopausal Status Alters Risk Calculation
A patient’s menopausal status is the third variable mandatory for the ROMA calculation. The algorithm uses distinct mathematical formulas for premenopausal and postmenopausal women. This differentiation is necessary because the normal reference ranges and the behavior of biomarkers, particularly CA-125, change significantly based on a woman’s hormonal environment.
Premenopausal women experience natural fluctuations in CA-125 levels, and benign conditions like fibroids or ovarian cysts are more common. The algorithm accounts for this higher baseline variability by applying a different weighting to the CA-125 and HE4 values. The premenopausal formula is adjusted to be more cautious about interpreting elevated CA-125 levels as a sign of cancer.
Conversely, in postmenopausal women, baseline CA-125 levels are expected to be lower and more stable. Therefore, any notable elevation carries a greater statistical significance for potential malignancy. This difference is reflected in the distinct coefficients used in the postmenopausal logistic regression formula. Using two separate equations ensures the final risk score is accurately contextualized to the patient’s hormonal status.
Interpreting the Final Risk Score
The final output of the ROMA test is a single numerical value, known as the Predictive Index (PI) or ROMA value, often expressed as a percentage indicating the probability of malignancy. This index is derived from a complex logistic regression calculation integrating the biomarker values with the menopausal-status-based coefficients. The primary function of this score is to stratify the patient into one of two categories: Low Risk or High Risk for finding epithelial ovarian cancer upon surgical evaluation.
The distinction between these categories uses specific, evidence-based cutoff values that differ based on menopausal status. For premenopausal women, a ROMA PI value of 1.14 or greater indicates a high risk of malignancy. The cutoff for postmenopausal women is significantly higher, with a ROMA PI value of 2.99 or greater signifying high risk.
The ROMA score is a predictive tool, not a definitive diagnosis of cancer. A high-risk score indicates an elevated statistical likelihood that the mass is malignant and serves as a strong recommendation for specialized care. The index guides patient management but does not confirm cancer, which requires surgical biopsy and pathology review.
When Doctors Use the ROMA Test
The clinical application of the ROMA test is highly specific and is not intended for general population screening. The test is used for women over 18 who have an ovarian adnexal mass, typically identified through imaging like an ultrasound, and only when surgery is planned to remove or investigate the mass.
The main purpose of the ROMA score is to triage patients. It helps physicians decide whether to refer the woman to a gynecologic oncologist, who specializes in cancer surgery, or to proceed with a general gynecologist. Patients classified as High Risk benefit from specialized treatment, which improves survival outcomes. Conversely, a Low Risk score suggests the mass is likely benign, allowing the patient to be managed in a community setting.
The ROMA test is not validated for use in all patients. Its utility is limited to epithelial ovarian cancer, making it less reliable for other, rarer types of ovarian tumors. Using ROMA outside the evaluation of a presurgical pelvic mass is inappropriate, as its accuracy diminishes significantly when used as a general screening tool.
Contraindications
The test should not be used in women who are:
- Pregnant.
- Currently undergoing chemotherapy.
- Have a history of cancer.