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HE4 (Human Epididymal Protein 4) Unit Converter
HE4 (Human Epididymal Protein 4) is a protease inhibitor protein whose expression is significantly elevated and thought to promote tumor growth in various epithelial cancers, most notably ovarian cancer. HE4 is minimally expressed in healthy tissues.
Clinically, HE4 is a key tumor marker used in the ROMA (Risk of Ovarian Malignancy Algorithm), often measured alongside CA 125, for the risk stratification of women presenting with a pelvic mass. Unlike CA 125, HE4 is less frequently elevated in benign gynecological conditions (like endometriosis), increasing specificity. Results are reported in molar concentration (pmol/L) or mass concentration (ng/mL).
SI Units / Molar
RecommendedPicomoles per liter (Standard International).
Mass Equivalents
Clinical Context
Reference Ranges (Typical):
• Premenopausal: < 70 pmol/L
• Postmenopausal: < 140 pmol/L
HE4 is interpreted in conjunction with CA 125 and clinical findings, frequently via the ROMA score, to estimate the risk of epithelial ovarian cancer in women with a pelvic mass. Elevated HE4 increases the likelihood of malignancy but is not diagnostic on its own. The molar conversion factor relies on an approximate molecular weight of 25 kDa: 1 ng/mL ≈ 40 pmol/L.
Clinical References
How to Use This Calculator
Follow these steps to get accurate clinical conversions instantly.
Enter Values
Input your laboratory results into the corresponding unit field (e.g., ng/mL). You can use either dot or comma decimals.
Automatic Conversion
The calculator works in real-time. As you type in one field, all other units (like pmol/L) are instantly updated.
Verify Units
Check the SI Units section. pmol/L is the international standard for protein tumor markers.
Reset
Use the Clear button to reset all fields before starting a new calculation.
Frequently Asked Questions & Tips
Yes. 1 ng/mL is exactly equal to 1 µg/L.
The two markers are complementary: CA 125 is sensitive but less specific, while HE4 is more specific, especially for certain types of ovarian cancer. Together they improve risk stratification.