Article Text
Abstract
Introduction/Background Pelvic magnetic resonance imaging (MRI)-findings indicating tumor size ≥4 cm, parametrial invasion and pelvic/paraaortic lymph node metastases are presently incorporated in the newly revised cervical cancer FIGO staging (2018) system and guide choice of treatment. Good interobserver agreement between radiologists for these staging parameters is however, critical if these are to guide therapy. This study aimed to evaluate the interobserver agreement for these staging parameters based on MRI in a large cervical cancer patient cohort.
Methodology A total of 421 patients with histologically confirmed uterine cervical cancer who had pelvic MRI at primary diagnostic work-up were included. Their MRI scans were read independently by two radiologists (with 4 and 10 yrs. of MRI reading experience, respectively) blinded for clinical information/FIGO stage. MRI findings indicating tumor size ≥4 cm, parametrial invasion and/or pelvic/paraaortic lymph node metastases (when >10 mm in short-axis diameter) were recorded. Interobserver agreement for these staging parameters were assessed using exact Fleiss kappa (κ). Agreement beyond chance was interpreted as poor (κ≤0.20), fair (κ=0.21–0.40), moderate (κ=0.41–0.60), good (κ=0.61–0.80) or very good (κ=0.81–1.00). The prognostic value of the MRI based staging parameters was assessed using Kaplan-Meier and log-rank test.
Results Interobserver agreement between the two radiologists for the evaluation of tumor size ≥4 cm was very good with a κ value of 0.83. For the evaluation of parametrial invasion and lymph node metastases, the agreement was good with κ values of 0.74 and 0.73, respectively. Presence of these imaging findings were also significantly associated with poor prognosis (figure 1).
Conclusion The interobserver reproducibility for the MRI-based staging parameters: tumor size ≥4 cm, parametrial invasion and pelvic/paraaortic lymph node metastases are very good and good, supporting the robustness of these imaging parameters for safe incorporation into the 2018 FIGO staging system.
Disclosure Nothing to disclose.