Agreement between preoperative transvaginal ultrasound and intraoperative macroscopic examination for assessing myometrial infiltration in low risk endometrioid carcinoma of the endometrium
Pineda L(1), Alcázar JL(1), Caparrós M(1), Mínguez JA(1), Idoate MA(2), Quiceno H(2), Solórzano JL(2), Jurado M(1).
To compare diagnostic performance of TVS and intraoperative macroscopic examination for determining myometrial infiltration in low risk endometrial cancer and to estimate the agreement between both methods.
One single center observational study comprising women with preoperative diagnosis of well or moderately differentiated endometrioid carcinoma of the endometrium. All women underwent preoperative transvaginal ultrasound (TVS) by a single examiner. According to subjective examiner's impression myometrial infiltration was stated as ≥ or < 50%. Surgical staging was performed in all cases. Intraoperative macroscopic examination of the removed uterus was done by pathologists unaware of ultrasound findings and myometrial infiltration was stated as ≥ or < 50%. Definitive histological diagnosis of myometrial infiltration was done by frozen section analysis and used as gold standard. Sensitivity and specificity with 95% confidence intervals for TVS and intraoperative macroscopic inspection were calculated and compared using McNemar test. Agreement between TVS and intraoperative macroscopic inspection was estimated using Cohen's Kappa index (κ) and percentage of agreement.
152 out of 209 eligible women were ultimately included. Patients' mean age was 60.9 years old (SD: 10.2, range: 32 to 91 years). Definitive histological diagnosis revealed that myometrial infiltration was < 50% in 114 women and ≥ 50% in 38 women, respectively. Sensitivity and specificity for TVS for detecting deep myometrial infiltration were 81.6% and 89.5%, respectively. Whereas these figures for intraoperative macroscopic examination were and 78.9% and 90.4%, respectively (McNemar test p > 0.05 when comparing TVS and intraoperative macroscopic examination). Agreement between both methods was moderate (κ = 0.54, 95%CI: 0.39 to 0.69. Percentage of agreement 82%).
Although the agreement between preoperative TVS and intraoperative macroscopic examination for detecting deep myometrial infiltration is only moderate; both methods had similar accuracy when compared with frozen section histology. Preoperative TVS might be reasonably proposed as a method for assessing myometrial infiltration instead of intraoperative macroscopic examination, at least when performed by an experienced examiner and image quality is not poor. Future research is needed to confirm this proposal.