Comparison of outcomes for MR-guided versus CT-guided high-dose-rate interstitial brachytherapy in women with locally advanced carcinoma of the cervix

Abstract

Objective The purpose was to compare local control (LC), overall survival (OS) and dose to the organs at risk (OAR) in women with locally advanced cervical cancer treated with MR-guided versus CT-guided interstitial brachytherapy (BT). Methods 56 patients (29 MR, 27 CT) were treated with high-dose-rate (HDR) interstitial BT between 2005–2015. The MR patients had been prospectively enrolled on a Phase II clinical trial. Data were analyzed using Kaplan-Meier (K-M) and Cox proportional hazards statistical modeling in JMP® & R®. Results Median follow-up time was 19.7 months (MR group) and 18.4 months (CT group). There were no statistically significant differences in patient age at diagnosis, histology, percent with tumor size >4 cm, grade, FIGO stage or lymph node involvement between the groups. Patients in the MR group had more lymphovascular involvement compared to patients in the CT group (p<0.01). When evaluating plans generated, there were no statistically significant differences in median cumulative dose to the high-risk clinical target volume or the OAR. 2-year K-M LC rates for MR-based and CT-based treatments were 96% and 87%, respectively (log-rank p=0.65). At 2 years, OS was significantly better in the MR-guided cohort (84% vs. 56%, p=0.036). On multivariate analysis, squamous histology was associated with longer OS (HR 0.23, 95% CI 0.07–0.72) in a model with MR BT (HR 0.35, 95% CI 0.08–1.18). Conclusion In this population of locally advanced cervical-cancer patients, MR-guided HDR BT resulted in estimated 96% 2-year local control and excellent early survival rates. Squamous cell histology was the most significant predictor for survival.

Clinical outcomes of carbon ion radiotherapy with concurrent chemotherapy for locally advanced uterine cervical adenocarcinoma in a phase 1/2 clinical trial (Protocol 1001)

“…Concurrent chemoradiotherapy (CCRT) is considered the primary treatment of choice for Stage IB2‐IVA uterine cervical squamous cell carcinoma based on randomized clinical trials and meta‐analyses . Recent studies have shown that CCRT and image‐guided brachytherapy improve the clinical outcome of patients with cervical carcinoma, especially squamous cell carcinoma . Conversely, few studies have investigated treatment options for adenocarcinomas; these are typically treated in a similar manner to squamous cell carcinomas .…”

Throwing the dart blind-folded: comparison of computed tomography versus magnetic resonance imaging-guided brachytherapy for cervical cancer with regard to dose received by the ‘actual’ targets and organs at risk

“…This is worrying since it correlates to inferior local control [ 4 ]. In fact, recently published data comparing MRI-guided versus CT-guided brachytherapy shows inferior overall survival for patients with CT-guided brachytherapy, which could possibly be explained by the results of the current study [ 21 ]. Five out of 11 of CT-guided plans had HRCTV mri D 90 higher than 8.3 Gy, extrapolated to total biological equivalent dose of more than 95 Gy.…”

Integration of MRI target delineation into rapid workflow cervical cancer brachytherapy: Impact on clinical outcomes

“…Published clinical data show favourable local control using this technique . Kamran et al . compared outcomes of MR‐guided versus CT‐guided brachytherapy and found that patients treated with MR‐guided brachytherapy had excellent toxicity rates, although was similar to CT‐guided brachytherapy, likely due to similar brachytherapy prescription dose between groups (35 Gy for each).…”