RESUMEN
BACKGROUND: Adenomyosis is histologically defined by the presence of endometrial glands and stroma in the myometrium. To date, there are no standardised ultrasound findings that reliably predict histological adenomyosis. AIMS: This study aimed to determine the diagnostic accuracy of a novel sonographic measurement for adenomyosis, the myometrial-cervical ratio (MCR), when compared with histopathological diagnosis. MATERIALS AND METHODS: A single-centre retrospective study was performed. The MCR was calculated from the pre-operative ultrasound, and histopathology reviewed for each case. Accuracy data were analysed in the form of 2 × 2 tables. The discriminative value of the MCR was summarised with a receiver operator characteristic (ROC) curve. Sub-analysis examined the impact of fibroids, hormonal suppression, menopausal status, parity and indication for surgery. RESULTS: Between 1 January 2016 and 31 December 2018, 982 patients underwent hysterectomy for benign non-obstetric indication and adequate pre-operative ultrasound was available for 260. The MCR demonstrated limited diagnostic ability for adenomyosis (area under the receiver operating characteristic curve (AUROC) 0.58, 95% CI 0.51-0.65). However, when applied to cases with no uterine fibroid included in the MCR calculation (n = 133) there was a strong association between MCR and diagnosis of adenomyosis (odds ratio: 5.79, 95% CI: 2.15, 15.62, P = 0.001) with AUROC for this model 0.68 (95% CI: 0.59, 0.77). At an MCR cut-point of 1.74, sensitivity is 67.16% and specificity is 66.15%, with 66.67% of samples correctly classified. CONCLUSIONS: While diagnostic accuracy was suboptimal, the MCR outperforms traditional ultrasound diagnostic features of adenomyosis. The MCR may offer a simple imaging measurement for adenomyosis.