Plenary Session
Tuesday, June 28, 2016
1:15 PM - 2:15 PMImage Guided Brachytherapy in Cervical Cancer: A Comparison between Intracavitary and Combined Intracavitary/Interstitial Brachytherapy in Regard to Doses to HR CTV, OARs and Late Morbidity - Early Results from the Embrace Study in 999 Patients
Tuesday, June 28, 2016
1:15 PM - 2:15 PM
Section snippets
Purpose
To compare the combined intracavitary/interstitial brachytherapy (IC/IS) with intracavitary brachytherapy alone (IC) in cervical cancer treated with definitive radio-chemotherapy and MRI guided adaptive brachytherapy within the EMBRACE study and the impact on target dose, OAR dose and late morbidity.
Methods
The EMBRACE database containing 1129 cervix cancer patients enrolled in the study with treatment completed before 09/2014 was used for this investigation. Patients having a MRI based parametrial infiltration status (PI) at time of brachytherapy (n=999) were divided according to their PI status at first brachytherapy: no PI (456 patients), proximal PI (412 patients) and distal + pelvic wall PI (122 patients). Patients in each group were compared according to the use of IC or IC/IS during the
Results
The median follow-up was 23 and 26 months for the IC/IS and IC group, respectively. Age and histology were balanced in all groups. HRCTV volume was significantly larger in IC/IS groups vs IC with no or proximal PI (Table 1). Morbidity was not significantly different between IC and IC/IS in patients with no PI. However, IC/IS patients with proximal PI had significantly less G2≥ bladder, bowel and overall morbidity at 3 years, but no difference in G2≥ rectal and vaginal morbidity (Table 1). A
Conclusion
These results demonstrate that regardless of the extent of PI, the dosimetric and clinical advantages of combined intracavitary/interstitial brachytherapy compared to intracavitary brachytherapy alone are substantial. IC/IS brachytherapy allows for a significantly higher HRCTV D90 (8Gy) in patients with distal and pelvic wall PI than IC brachytherapy while leading to less rectal and bowel morbidity. For patients with proximal PI, the use of IC/IS brachytherapy was associated with less bladder,