IOTA Simple Rules for Ovarian Mass Classification
IOTA simple rules classify an adnexal mass as benign (B-features only), malignant (M-features only) or inconclusive (both or neither). Prospectively the rules applied to 76% of masses, with sensitivity 95% and specificity 91% (Timmerman 2008).
Score interpretation
Only B-features present: classified benign by the IOTA simple rules.
→ Manage as a benign mass per local pathway; re-image if symptoms or appearances change.
Both M- and B-features, or neither: the simple rules cannot classify this mass.
→ Expert (level III) ultrasound or another validated method (e.g. IOTA ADNEX, RMI); gynaecological MDT discussion.
Only M-features present: classified malignant by the IOTA simple rules.
→ Refer urgently to gynaecological oncology (suspected cancer pathway); CA-125 and staging imaging; MDT discussion.
Interpretation bands for the IOTA Simple Rules. Apply clinical judgement and local guidance.
References
- Timmerman D et al. Simple ultrasound-based rules for the diagnosis of ovarian cancer. Ultrasound Obstet Gynecol. 2008;31(6):681–690.
Related
Curated clinical cross-links plus same-class fallbacks.
Decision support only — verify against a current formulary, NICE, or your local guideline before clinical use.