RMI (Risk of Malignancy Index)
RMI 1 (Jacobs 1990); threshold 200Calculates the Risk of Malignancy Index for an adnexal mass from ultrasound feature count (U), menopausal status (M), and serum CA-125, flagging scores above 200 as high risk warranting gynae-oncology referral.
Also searched as: ovary · adnexal mass · CA-125 · ovarian cancer · gynecology · ovarian · adnexal · pelvic mass
Information
Incomplete input
- Please provide: menopausal status.
How this tool works
The Risk of Malignancy Index combines three preoperative factors into a single product: an ultrasound score based on morphologic features of malignancy, a menopausal score, and the absolute serum CA-125 concentration in U/mL. Originally described by Jacobs and colleagues, RMI remains widely used in triage pathways because it is simple, uses routinely available data, and stratifies who should be referred to a specialist multidisciplinary team. A threshold of 200 is the most commonly applied cut-off for high risk. RMI does not replace expert ultrasound pattern recognition (IOTA Simple Rules, ADNEX, O-RADS) and performs less well in premenopausal women and borderline tumors.
References
- Jacobs I, et al. Br J Obstet Gynaecol 1990;97:922-929 (RMI derivation)
- Radiopaedia — Risk of malignancy index in ovarian tumours
- MDCalc — Risk of Malignancy Index (RMI)
Implemented from the cited published sources. Educational use only; confirm against current guidelines before clinical use.
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