Treatment of hepatic metastases of breast cancer with CT-guided interstitial brachytherapy - A phase II-study

Purpose: The aim of the study was the evaluation of feasibility, safety and effectiveness of interstitial brachytherapy for the treatment of hepatic metastases of breast cancer. Materials and methods: Forty-one consecutive patients with 115 unresectable hepatic metastases of breast cancer were included in this phase-II-trial. They were treated in 69 interventions of CT-guided-interstitial-brachytherapy of the liver. Brachytherapy was applied as a single fraction high-dose-irradiation (15-25 Gy (Gray)) using a (192)[r-source of 10 Ci. Nineteen patients presented systemically pretreated extrahepatic tumors. Primary endpoints were complications, local tumor control and progression-free survival. Results: The median tumor diameter was 4.6 cm (1.5-11 cm). The median irradiation time per intervention was 26.5 min (range: 7-47 min). The applied median minimal dose at the CTV (clinical target volume) margin was 18.5 Gy (12-25 Gy). In 69 interventions and during the postinterventional period, one major complication (symptomatic post-interventional bleeding) (1.5%) and six minor complications occurred (8.7%). The median follow-up time was 18 months (range: 1-56). After 6, 12 and 18 months, local tumor control was 97%, 93.5% and 93.5%, intra- and extrahepatic progression free survival was 53%, 40% and 27%, and overall survival was 97%, 79% and 60%, respectively. Conclusion: CT-guided-brachytherapy is safe and effective for the treatment of liver metastases of breast cancer. (C) 2011 Elsevier Ireland Ltd. All rights reserved. Radiotherapy and Oncology 100 (2011) 314-319