Consecutive magnetic resonance imaging during brachytherapy for cervical carcinoma: predictive value of volume measurements with respect to persistent disease and prognosis

Abstract

BackgroundCervical cancer is associated with a high yearly mortality. The presence of persistent disease after radiotherapy is a significant predictor of patient survival.The aim of our study was to assess if tumor volume regression measured with MR imaging at the time of brachytherapy can discriminate between patients who eventually will achieve a complete response to radiotherapy from those who will not. The second objective was to evaluate whether tumor volume regression predicts overall treatment failure.MethodsMRI was evaluated quantitatively in 35 patients; by means of tumor volumetry on T2-weighted MR images before treatment, at the first BCT application, and at the final BCT. The MR images were independently analyzed by two investigators. As a reference standard histopathologic confirmation of residual tumor and/or clinical exam during follow-up > 1 year were used. Area under the curve were compared, P-values <0.05 were considered significant.ResultsThere was a good correlation between volume measurements made by the two observers. A residual tumor volume >9.4 cm3 at final BCT and tumor volume regression < 77 % of the pre-treatment volume were significantly associated with local residual tumor after completion of therapy (p < 0.02) (AUC, 0.98-1.00). A volume >2.8 cm3 at final BCT was associated with overall treatment failure (p < 0.03).ConclusionOur study shows that volume analysis during BCT is a predictive tool for local tumor response and overall treatment outcome. The potential of local response assessment to identify patients at high risk of overall treatment failure is promising.

Tumor Size at Magnetic Resonance Imaging Association With Lymph Node Metastasis and Lymphovascular Space Invasion in Resectable Cervical Cancer: A Multicenter Evaluation of Surgical Specimens

“…According to the previous reports, tumor volume was calculated by multiplying the sum of tumor areas by the section thickness. 19 , 20 Tumor area was manually outlined on the sagittal or axial T2-weighted image images along the border of the each suspected tumor slice (Fig. 1 ).…”

Diagnostic significance of magnetic resonance imaging in patients with cervical cancer after brachytherapy: a meta-analysis

“…Further analysis revealed that the tumor size of the patients in the study by Vincens et al. (18) was much smaller (∼1 cm) than that of the patients in the other studies (16,17,20). This finding suggested that the size of the tumor in cervical cancer was a critical factor in the accuracy of MRI after BCT.…”

“…A careful analysis of all the studies revealed that the sensitivity, specificity, and accuracy (80%, 55.6%, and 64.3%, respectively) in the research by Vincens et al (18) were much lower than the corresponding values in the other three studies. Further analysis revealed that the tumor size of the patients in the study by Vincens et al (18) was much smaller ($1 cm) than that of the patients in the other studies (16,17,20). This finding suggested that the size of the tumor in cervical cancer was a critical factor in the accuracy of MRI after BCT.…”

“…Of these, 156 were excluded after reviewing the titles and abstracts, as their research purpose was different from that of the present study. After a careful review, seven studies met the inclusion criteria (10,11,(16)(17)(18)(19)(20). Of these, only four studies included a histological or gynecological test as the gold standard and were included in the present study (16)(17)(18)20).…”

“…Based on these findings, MRI-guided brachytherapy (BCT) has been included in treatment planning (12) and been shown to significantly improve outcomes in locally advanced cervical cancer (13). Although MRI has been proven to be a powerful tool for the measurement of the tumor volume in cervical carcinomas and ADC staging pretreatment (14,15), there has been very little research on the accuracy of MRI detection after BCT (10,11,(16)(17)(18)(19)(20). Furthermore, to date, no meta-analysis of the diagnostic accuracy of MRI has been performed.…”