Susanne Fridsten

Timing of MRI for early treatment response prediction of chemoradiotherapy in uterine cervical cancer

To explore the optimal use of MRI including time point to predict early treatment response during definitive chemoradiotherapy in cervical carcinoma. Pilot study including 15 patients with cervical carcinoma stage IIB-IIIB (FIGO 2009) scheduled for chemoradiotherapy. All patients underwent four MRI examinations (at baseline, 3 weeks, 5 weeks, and 12 weeks after treatment start). Maximum tumor size, size change (Δsize), visibility on diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) mean and change in ADC (ΔADC) at the different time points were recorded. 7/15 patients relapsed during the study period, referred to as "poor prognosis" (PP) and the remaining 8/15 are referred to as "good prognosis" (GP). At all four time points, the tumors in the PP patients were larger than in the GP patients. Tumor size did change between the time point but this was not significant between the groups. Visible tumor on high b-value DWI reached a sensitivity and specificity for predicting prognostic group being highest at 5 weeks, 83 % (5/6) and 63 % (5/8), respectively. The combination of tumor size at baseline and visible tumor on DWI at 5 weeks, resulted in an area under the curve (AUC) = 0.83. At 12 weeks, no GP patients, but 2/7 PP patients showed visible tumor on DWI. Addition of ADC-values in the analysis did not improve the predictive value at any time point. This pilot study indicates that the tumor size on baseline MRI, combined with tumor visibility on DWI at 5 weeks, may predict outcome of chemoradiotherapy.

Interobserver agreement of transvaginal ultrasound and magnetic resonance imaging in local staging of cervical cancer

ABSTRACTObjectiveTo evaluate interobserver agreement for the assessment of local tumor extension in women with cervical cancer, among experienced and less experienced observers, using transvaginal ultrasound (TVS) and magnetic resonance imaging (MRI).MethodsThe TVS observers were all gynecologists and consultant ultrasound specialists, six with and seven without previous experience in cervical cancer imaging. The MRI observers were five radiologists experienced in pelvic MRI and four less experienced radiology residents without previous experience in MRI of the pelvis. The less experienced TVS observers and all MRI observers underwent a short basic training session in the assessment of cervical tumor extension, while the experienced TVS observers received only a written directive. All observers were assigned the same images from cervical cancer patients at all stages (n = 60) and performed offline evaluation to answer the following three questions: (1) Is there a visible primary tumor? (2) Does the tumor infiltrate > ⅓ of the cervical stroma? and (3) Is there parametrial invasion? Interobserver agreement within the four groups of observers was assessed using Fleiss kappa (κ) with 95% CI.ResultsExperienced and less experienced TVS observers, respectively, had moderate interobserver agreement with respect to tumor detection (κ (95% CI), 0.46 (0.40–0.53) and 0.46 (0.41–0.52)), stromal invasion > ⅓ (κ (95% CI), 0.45 (0.38–0.51) and 0.53 (0.40–0.58)) and parametrial invasion (κ (95% CI), 0.57 (0.51–0.64) and 0.44 (0.39–0.50)). Experienced MRI observers had good interobserver agreement with respect to tumor detection (κ (95% CI), 0.70 (0.62–0.78)), while less experienced MRI observers had moderate agreement (κ (95% CI), 0.51 (0.41–0.62)), and both experienced and less experienced MRI observers, respectively, had good interobserver agreement regarding stromal invasion (κ (95% CI), 0.80 (0.72–0.88) and 0.71 (0.61–0.81)) and parametrial invasion (κ (95% CI), 0.69 (0.61–0.77) and 0.71 (0.61–0.81)).ConclusionsWe found interobserver agreement for the assessment of local tumor extension in patients with cervical cancer to be moderate for TVS and moderate‐to‐good for MRI. The level of interobserver agreement was associated with experience among TVS observers only for parametrial invasion. © 2021 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.