Practical guidance for applying the ADNEX model from the IOTA group to discriminate between different subtypes of adnexal tumors

Abstract

All gynecologists are faced with ovarian tumors on a regular basis, and the accurate preoperative diagnosis of these masses is important because appropriate management depends on the type of tumor. Recently, the International Ovarian Tumor Analysis (IOTA) consortium published the Assessment of Different NEoplasias in the adneXa (ADNEX) model, the first risk model that differentiates between benign and four types of malignant ovarian tumors: borderline, stage I cancer, stage II-IV cancer, and secondary metastatic cancer. This approach is novel compared to existing tools that only differentiate between benign and malignant tumors, and therefore questions may arise on how ADNEX can be used in clinical practice. In the present paper, we first provide an in-depth discussion about the predictors used in ADNEX and the ability for risk prediction with different tumor histologies. Furthermore, we formulate suggestions about the selection and interpretation of risk cut-offs for patient stratification and choice of appropriate clinical management. This is illustrated with a few example patients. We cannot propose a generally applicable algorithm with fixed cut-offs, because (as with any risk model) this depends on the specific clinical setting in which the model will be used. Nevertheless, this paper provides a guidance on how the ADNEX model may be adopted into clinical practice.

Keywords: CA-125; Ovarian neoplasms; decision support techniques; practical guidance; ultrasonography.

Figures

Fig. 1. Ultrasound characteristics selected as predictors in the ADNEX model.

Fig. 2. Average predicted risks for different histologies.

Fig. 3. Illustration of the ADNEX model for case 1.

Fig. 4. Illustration of the ADNEX model for case 2.

Fig. 5. Example of a two-step approach towards the clinical use of ADNEX predicted risks.