A Multicenter International Temporal and External Validation Study of the Ultrasound-based Endometriosis Staging System

Mercedes Espada, Mathew Leonardi, Kristina Aas-Eng, K. Aas‐Eng, Aas-Eng K, Chuan Lu, Chuan Lü, Lionel Reyftmann, L. Reyftmann, Tetstall E, Emma Tetstall, Basia Slusarczyk, Slusarczyk B, Joanne Ludlow, J. Ludlow, Ludlow J, Hudelist G, Gernaud Hudelist, Shannon Reid, S. Reid, G. Condous, George Condous, Condous G
Journal of minimally invasive gynecology · 2020 · vol. 28(1) , pp. 57–62 · doi:10.1016/j.jmig.2020.04.009 · PMID:32289555 · W3016144633
article OA: closed CC0 ⤵ 19 in-corpus citations
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This multicenter international study validated an ultrasound-based system for staging endometriosis, assessing its reliability and accuracy across different centers and over time.

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Abstract

Study objectiveThe aim of this study was to validate temporally and externally the ultrasound-based endometriosis staging system (UBESS) to predict the level of complexity of laparoscopic surgery for endometriosis.DesignA multicenter, international, retrospective, diagnostic accuracy study was carried out between January 2016 and April 2018 on women with suspected pelvic endometriosis.SettingFour different centers with advanced ultrasound and laparoscopic services were recruited (1 for temporal validation and 3 for external validation).PatientsWomen with pelvic pain and suspected endometriosis.InterventionsAll women underwent a systematic transvaginal ultrasound and were staged according to the UBESS system, followed by classification of laparoscopic level of complexity according to the Royal College of Obstetricians and Gynaecologists (RCOG) levels 1 to 3.Measurements and main resultsUBESS I, II, and III were then correlated with RCOG levels 1, 2, and 3, respectively. A comparison between temporal and external sites (skipping "A") and between each site was performed in terms of the diagnostic accuracy of UBESS to predict RCOG laparoscopic skill level. A total of 317 consecutive women who underwent laparoscopy with suspected endometriosis were included. Complete transvaginal ultrasound and laparoscopic surgical outcomes were available for 293/317 (92.4%). At the temporal site, the accuracy, sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio of UBESS I to predict RCOG level 1 were 80.0%,73.8%, 94.9%, 97.2%, 60.2%, 14.5%, and 0.3%, respectively; of UBESS II to predict RCOG level 2 were 81.0%, 70.6%, 82.0%, 26.7%, 96.8%, 3.9%, and 0.3%, respectively; of UBESS III to predict RCOG level 3 were 91.0%, 85.7%, 92.4%, 75.0%, 96.1%, 11.3%, and 0.2%, respectively. At the external sites, the results of UBESS I to predict RCOG level 1 were 90.3%, 92.0%, 88.4%, 90.2%, 90.5%, 7.9%, and 0.1% respectively; UBESS II to predict RCOG level 2 were 89.2%, 100.0%, 88.5%, 37.5%, 100.0%, 8.7%, and 0.0%, respectively; and UBESS III to predict RCOG level 3 were 86.0%, 67.6%, 98.2%, 96.2%, 82.1%, 37.8%, and 0.3%, respectively. When patients requiring ureterolysis (i.e., RCOG level 3) in the absence of bowel endometriosis were excluded (n = 54), the sensitivity of UBESS III to correctly classify RCOG level 3 increased from 85.7% to 96.7% at the temporal site (n = 42) and from 67.6% to 96.0% at the external sites (n = 12) (p <.005).ConclusionThe results from this external validation study suggest that UBESS in its current form is not generalizable unless there is either or both bowel deep endometriosis and cul-de-sac obliteration present. The major limitation appears to be the misclassification of women who require surgical ureterolysis in the absence of bowel endometriosis.

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Condition tags

endometriosischronic_pelvic_pain

MeSH descriptors

Endometriosis Ultrasonography Adult Australia Austria Chronic Pain Chronic Pain Chronic Pain Chronic Pain Douglas' Pouch Douglas' Pouch Douglas' Pouch Endometriosis Endometriosis Endometriosis Female Humans Intestinal Diseases Intestinal Diseases Intestinal Diseases

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