ROMA Index Calculator
Use this tool to estimate the Risk of Ovarian Malignancy Algorithm (ROMA) score from CA-125, HE4, and menopausal status.
Note: Cutoffs can vary by lab platform and institution. This calculator is educational and not a medical diagnosis.
What Is the ROMA Index?
The ROMA Index (Risk of Ovarian Malignancy Algorithm) is a clinical decision support score used to estimate the probability that an ovarian mass is associated with malignancy. It combines two biomarkers—CA-125 and HE4—plus menopausal status into a single percentage.
An index ROMA calculator is useful because no single marker is perfect in every patient group. CA-125 can be elevated in benign conditions, and HE4 behavior may differ across age groups and renal function. Combining them through a validated equation improves risk stratification in many settings.
Inputs Used by This Index ROMA Calculator
1) CA-125 (U/mL)
CA-125 is a well-known ovarian cancer biomarker, but elevations can occur in non-cancer conditions such as endometriosis, menstruation-related changes, and inflammation. It is informative but should always be interpreted with context.
2) HE4 (pmol/L)
HE4 is another biomarker frequently used in adnexal mass assessment. In some clinical workflows, HE4 can improve discrimination when paired with CA-125.
3) Menopausal status
The ROMA formula uses different coefficients for premenopausal and postmenopausal patients, reflecting biological and baseline risk differences between the two groups.
Formula Behind the Calculator
This page uses a common ROMA implementation:
- Premenopausal PI = -12.0 + 2.38 × ln(HE4) + 0.0626 × ln(CA-125)
- Postmenopausal PI = -8.09 + 1.04 × ln(HE4) + 0.732 × ln(CA-125)
- ROMA % = exp(PI) / (1 + exp(PI)) × 100
Where ln is the natural logarithm. Because of the logarithm, both biomarker values must be positive numbers.
How to Interpret Results
Many references use approximate decision thresholds such as:
- Premenopausal: high-risk if ROMA ≥ 11.4%
- Postmenopausal: high-risk if ROMA ≥ 29.9%
These are common values, but your lab or institution may apply different cutoffs depending on assay platform, population, and policy. Always verify local standards.
Example Use Case
If a premenopausal patient has CA-125 of 40 U/mL and HE4 of 65 pmol/L, the calculated ROMA percentage may fall into a lower-risk range relative to the premenopausal threshold. If those biomarkers are much higher, the percentage can move quickly above the cutoff and suggest need for specialist referral.
Important Limitations
- ROMA supports risk assessment; it does not confirm or exclude cancer by itself.
- Imaging findings, history, physical exam, and other labs remain essential.
- Assay methods differ between laboratories.
- Renal function and comorbid conditions may influence biomarker values.
Practical Tips for Better Use
Check units carefully
CA-125 should be entered in U/mL and HE4 in pmol/L for this implementation. Incorrect unit conversion can distort results.
Use repeat measurements thoughtfully
Trend information can be useful, but serial interpretation should be clinician-guided and linked to imaging and symptoms.
Document assay and threshold source
For reproducibility, note the laboratory assay and the cutoff policy used during interpretation.
Bottom Line
This index ROMA calculator gives a fast, transparent way to compute ROMA percentage from standard inputs. It is best used as a structured aid within full clinical evaluation, not as a stand-alone diagnostic tool. If results are concerning, discuss them promptly with a qualified healthcare professional.