Introduction: The dose administered to the tumour bed is a risk-factor for local recurrence in localised breast cancer following breast-conserving surgery.
Materials and methods: All patients (n=94) received 50 Gy external beam radiotherapy and one application of 700 cGy at 85% isodose with high dose rate brachytherapy.
Results: Of the cases, 84% were infiltrating ductal carcinoma; 31.2% were G3; 28% were intraductal component > 25%; 54% had margin < 1 cm or unknown. With a mean follow-up of 65 months (range: 36-107 months), the overall actuarial survival at 5 and 8 years was 93.2% and 84.2%, respectively; disease-free survival was 88.3% and 84.6%, respectively; local control was 92.2% and 88.75%, respectively. Local recurrence rate was 5.3%, and distant dissemination rate was 8.5%. Among the risk-factors analysed, only the presence of 4 or more lymph node involvement implied a higher risk for local recurrence (p =0.0001). For distant dissemination, the risk-factors were: 4 or more lymph nodes involved (p = 0.0001),G3 (p =0.029), tumour >3 cm (p = 0.001), irradiation volume with external beam radiotherapy (p =0.0001), and presence of local recurrence (p = 0.001).
Conclusion: High dose rate brachytherapy is an effective method for reducing local recurrence, and increasing local control.