IOTA Simple Rules and SRrisk calculator to diagnose ovarian cancer
We are writing to you to explain why the web applications of ADNEX and of LR1, LR2 and SRRisk are no longer available on the IOTA website, and why the ADNEX app and the other IOTA apps are no longer available in app-store or Google play. The explanation is a change in the European Medical Device Regulation (MDR), a set of regulations that governs the sale and distribution of medical devices within the European Union (EU).
According to the new MDR, the ADNEX calculator and the other IOTA calculators (web-application, app for apple and android devices and any other applications of the IOTA calculators) are now classified as medical devices. As a result, these calculators must undergo a certification process before they can be legally made available to healthcare professionals. Therefore, we have suspended the availability of the ADNEX calculator and the other calculators on our website until we have received the required certification, and we have also removed them from app-store and google play.
The process of obtaining MDR certification for medical devices is complex, very expensive and time-consuming. The IOTA steering committee is now working hard to obtain certification of the ADNEX web application, but we cannot provide reliable information on how long this process may take.
Please, observe that it is not the ADNEX model itself that is questioned and needs "certification". The ADNEX model has been externally validated on thousands of patients in different countries and settings and has been shown to have excellent ability to discriminate between benign and maligant adenxal masses. It is the calculator itself (web-application or app for android and apple devises) that needs to obtain certification.
An ADNEX app and some of the other IOTA risk calculation apps are available in many ultrasound systems. The apps in ultrasound systems have the necessary certification according to the manufacturers of the ultrasound machines. If you do not have an ultrasound machine with the ADNEX app or any of the other IOTA apps, we suggest you use the IOTA Benign descriptors or the IOTA Simple Rules.
We are very sorry about the situation. We know it causes substantial inconvenience.
If you have any questions or concerns, please contact us. We will keep you informed about any updates regarding the availability of the IOTA calculators.
Thank you for your understanding and continued support.
The IOTA Steering Committee:
Ben van Calster
1. The original Simple Rules (2008)
The Simple Rules are a preoperative classification system for ovarian tumors, consisting of five features typical for benign tumors (B-features) and five features typical for malignant tumors (M-features), see Figure 1. The Simple Rules can be used to diagnose ovarian cancer in women who have at least one persistent adnexal (ovarian, para-ovarian, and tubal) tumor and are considered to require surgery. Based on which of the B- and M-features that apply, tumors are classified as Benign, Malignant or Inconclusive:
- Benign - Only B-features apply
- Malignant - Only M-features apply
- Inconclusive - no features apply, or both B- and M-features apply
Figure 1. The 10 features from the Simple Rules
The Simple Rules were developed by clinicians and statisticians from the International Ovarian Tumor Analysis (IOTA) group, based on clinical and ultrasound data from 1066 women recruited at 9 centers in 5 countries (Italy, Belgium, Sweden, France, and UK). All patients included required surgery as judged by a local clinician. All current diagnostic models for adnexal tumors (e.g. IOTA models, RMI, ROMA) have been created for patients undergoing surgery, i.e. patients selected for expectant management were excluded when creating the model.
The manuscript describing the Simple Rules is published in Ultrasound in Obstetrics and Gynecology (Timmerman et al, 2008).1The Simple Rules have been successfully validated in several studies.2-13
The Simple Rules cannot replace training and experience in ultrasonography and cannot compensate for poor quality ultrasound equipment. The parameters used in the Simple Rules are based on the terms and definitions as published by the IOTA group.14
The original SR is implemented electronically in various formats:
By installing this software you agree to the terms of the License Agreement.
2. The Simple Rules risk (SRrisk) calculation (2016)
The Simple Rules have the important drawback that they do not give a predicted risk, and hence not a level of confidence in the classification. This was overcome by the development of the SRrisk calculation tool15. This is based on a logistic regression model with the ten features and the type of center (oncology center vs other) as predictors. Oncology centers were defined as tertiary referral centers with a specific gynecological oncology unit.
The model was developed by clinicians and statisticians from the International Ovarian Tumor Analysis (IOTA) group, and is based on clinical and ultrasound data from almost 6000 women recruited at 24 center in 10 countries (Italy, Belgium, Sweden, Czech Republic, Poland, France, UK, China, Spain, and Canada). All patients included required surgery as judged by a local clinician. All current diagnostic models for adnexal tumors (e.g. IOTA models, RMI, ROMA) have been created for patients undergoing surgery, i.e. patients selected for expectant management were excluded when creating the model. As a consequence the Simple Rules risk calculation cannot be applied to conservatively treated adnexal tumors.
The manuscript describing the SRrisk model is published in American Journal of Obstetrics and Gynecology (Timmerman, Van Calster, et al, 2016).15
The Simple Rules risk calculation cannot replace training and experience in ultrasonography and cannot compensate for poor quality ultrasound equipment. The parameters used in the Simple Rules risk calculation are based on the terms and definitions as published by the IOTA group.14
SR Risk Calculator can be accessed here: SR Risk Calculator
- Timmerman D, et al. Ultrasound Obstet Gynecol 2008;31:681-90.
- Timmerman D, et al. BMJ 2010;341:c6839.
- Testa AC, Kaijser J, et al. Br J Cancer 2014;111:680-8.
- Fathallah K, et al. Gynecol Obstet Fertil 2011;39:477-81.
- Hartman CA, et al. Ultrasound Obstet Gynecol 2012;40:360-6.
- Alcázar JL, et al. Ultrasound Obstet Gynecol 2013;42:467-71.
- Sayasneh A, et al. Br J Cancer 2013;108:2448-54.
- Tantipalakorn C, et al. Asian Pac J Cancer Prev 2014;15:5123-6.
- Nunes N, et al. Ultrasound Obstet Gynecol 2014;44:503-14.
- Tinnangwattana D, et al. Asian Pac J Cancer Prev 2015;16:3835-8.
- Ruiz de Gauna B, et al. Eur J Obstet Gynecol Reprod Biol 2015;191:10-4.
- Knafel A, et al. Ultraschall Med 2015 Jun 30. [Epub ahead of print].
- Alcázar JL, et al. Ultrasound Obstet Gynecol 2016;48:397-402.
- Timmerman D, et al. Ultrasound Obstet Gynecol 2000;16:500-505.
- Timmerman D, Van Calster B, et al. Am J Obstet Gynecol 2016;214:424-437.