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ADNEX Model (IOTA)

IOTA ADNEX (Van Calster BMJ 2014; Evidencio formula v2)

Implements the IOTA ADNEX multinomial logistic model to estimate probabilities that an adnexal mass is benign, borderline, stage I primary invasive, stage II–IV primary invasive, or metastatic, using age, optional CA-125, and six ultrasound predictors.

Also searched as: ovary · adnexal · ovarian cancer · ultrasound · CA-125 · ovarian · pelvic mass

Patient age
years
Serum CA-125 (optional)

Leave blank to use the no-CA-125 model. Model still works without CA-125.

U/mL
Maximum diameter of lesion
mm
Maximum diameter of largest solid component

Enter 0 if there is no solid component. Cannot exceed lesion diameter.

mm
More than 10 cyst locules
Number of papillary projections

Papillations ≥3 mm in height. Enter 4 for more than three.

Acoustic shadows present
Ascites present
Examination performed at an oncology referral center

Oncology centers have higher prior odds of malignancy in the model.

Information
Incomplete input
  • Please provide: patient age.

How this tool works

ADNEX (Assessment of Different NEoplasias in the adneXa) was developed by the International Ovarian Tumor Analysis group to move beyond binary benign-versus-malignant classification. Using three clinical and six ultrasound predictors, a polytomous logistic regression yields simultaneous probabilities for five outcome classes. The model can be run with or without serum CA-125; omitting CA-125 slightly reduces discrimination among malignant subtypes but preserves strong benign-versus-malignant performance. Coefficients used here are taken from the published Evidencio / IOTA implementation of the Van Calster BMJ 2014 model. For medicolegal or trial use, confirm figures against the official IOTA ADNEX calculator (iotagroup.org), as software versions may apply shrinkage or updates.

References

Implemented from the cited published sources. Educational use only; confirm against current guidelines before clinical use.

Clinical questions that use this

Vetting guides that reach for this tool.

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