Transferability of the early-stage ovarian malignancy (EOM) score: an external validation study that includes advanced-stage and metastatic ovarian cancer

Abstract

© 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature. Purpose: To validate the diagnostic performance of the Early-stage Ovarian Malignancy (EOM) score in an external dataset that includes advanced-stage and metastatic ovarian cancer. Methods: The data from two cross-sectional cohorts were used in the statistical analysis. The development dataset of the EOM score was collected in Phrapokklao Hospital between September 2013 and December 2017. The validation dataset was collected in Maharaj Nakorn Chiang Mai Hospital between April 2010 and March 2018. The internal and external performance of the EOM score was evaluated in terms of discrimination via area under the receiver-operating characteristic curve (AuROC) and calibration. Results: There were 270 and 479 patients included in the development and validation datasets, respectively. The prevalence of ovarian malignancy was 20.0% (54/270) in the development set and 30.3% (145/479) in the validation set. The EOM score had excellent discriminative ability in both the development and validation sets (AuROC 88.0 (95% CI 82.6, 93.9) and 88.0 (95% CI 84.3, 91.4), respectively). The EOM score also showed good calibration in both datasets. Conclusions: The EOM score had consistent diagnostic performance in the external validation data. It is recommended for use as a triage tool in patient referrals instead of the RMI in settings where experienced sonographers are not available.