Scientific publications

External validation of IOTA simple descriptors and simple rules for classifying adnexal masses

Jan 7, 2016 | Magazine: Ultrasound in Obstetrics & Ginecology

Alcázar JL (1), Pascual MA (2), Graupera B (2), Aubá M (1), Errasti T (1), Olartecoechea B (1), Ruiz-Zambrana A (1), Hereter L (2), Ajossa S (3), Guerriero S (3).


To assess the diagnostic performance of IOTA proposed three-step strategy for discriminating benign from malignant adnexal masses METHODS: Prospective observational study performed at two tertiary care university hospitals comprising women diagnosed as having an adnexal mass evaluated by transvaginal/transabdominal ultrasound from December 2012 to December 2014.

Non-expert examiners performed the initial ultrasound evaluation. The examiner had to classify the mass use simple descriptors (SD) and if not possible use simple rules (SR) as second-step. In "inconclusive" masses, then expert classified the mass according to their subjective impression. Masses were managed expectantly with serial follow-up or surgically, according to each center protocol. Histology was used as reference standard.

Those masses managed expectantly and with at least one year follow-up were considered as benign for analytical purposes. Women with less than one year follow-up were not included.


Six hundred and sixty-six women were included (median age: 41 years, range: 18 to 81 years) of whom 514 premenopausal and 152 postmenopausal. 362 masses were removed surgically (53 malignant and 309 benign), 71 masses resolved spontaneously and 233 were managed expectantly. 67.3% (448/666) masses could be classified using SD and out of the 218 that could not, 147 (67.4%) were classified using SR. Of remaining 71 masses, the expert examiner classified 45 cases as benign, 12 cases as malignant and 14 cases as uncertain. Overall sensitivity, specificity, + likelihood ratio and - likelihood ratio were 94.3%, 94.9%, 18.6 and 0.06, respectively.


The IOTA three-step strategy based on the sequential use of SD, SR and expert evaluation performs well.

CITATION  Ultrasound Obstet Gynecol. 2016 Sep;48(3):397-402. doi: 10.1002/uog.15854