CT versus MRI for Image-Guided Brachytherapy in Locally Advanced Cervical Cancer: A Propensity Score-Matched Analysis

Area of Science:

• Oncology
• Radiotherapy
• Medical Imaging

Background:

• Magnetic Resonance Imaging (MRI) is the standard for image-guided brachytherapy (IGBT) in cervix cancer.
• Computed Tomography (CT) scans are frequently used, but comparative evidence is limited.

Purpose of the Study:

• To compare the efficacy and safety of CT-guided versus MRI-guided IGBT for cervix cancer.
• To evaluate local control, disease-free survival, and adverse events between the two imaging modalities.

Main Methods:

• Retrospective study of patients with FIGO (2018) stage IB3-IVA cervix cancer treated with (chemo)radiation and CT-Ultrasound or MRI-based IGBT.
• Propensity score matching (PSM) was used to compare outcomes between CT and MRI cohorts.
• Key dosimetric parameters and clinical outcomes including local control, disease-free survival, and toxicity were analyzed.

Main Results:

• After PSM, 120 patients were in each CT and MRI cohort.
• No significant difference was observed in 3-year local control (89% vs. 92%) or disease-free survival (71% vs. 73%) between CT and MRI groups.
• Late grade ≥3 gastro-intestinal and genitourinary toxicities were comparable between the two groups.

Conclusions:

• CT-based brachytherapy may offer comparable oncological outcomes to MRI-based brachytherapy for cervix cancer.
• These findings are hypothesis-generating and require validation through prospective clinical trials.