MammoSite brachytherapy for low-risk breast carcinoma: Toxicity, cosmetic evaluation and quality-of-life results of a phase II study

Abstract

11016 Background: The MammoSite is a device that was developed with the goal of making breast-conserving surgery more widely available. Our objective was to evaluate the MammoSite device performances after an open cavity placement procedure and quality of life in highly selected patients with early-stage breast cancer. Methods: From March 2003 to March 2005, 43 patients with T1 breast cancer were enrolled in a phase II prospective study. Twenty-five (58%) patients were qualified for HDR brachytherapy delivery. The median age was 72 years (range: 60–75). Twenty-five (58%) were treated with high-dose rate brachytherapy using the MammoSite applicator to deliver 34 Gy prescribed at 1 cm from the balloon surface in 10 fractions over 5 to 8 days. Results: The main disqualifying factor was pathologic sentinel node involvement. After a median follow-up of 13 months, there were no local recurrences. Seventeen (68%), 13 (52%), 7 (28%), 5 (20%) and 4 (16%) patients had erythema, seroma, inflammation, hematoma and infection, respectively. Only 2 patients developed telangiectasia. At 3 months breast erythema grade ≥ 2 was significantly correlated to cosmetic results (12.5% in the ‘good to excellent‘ versus 57% in the ‘poor to fair‘ group; p = 0.045). The strongest trend of excellent cosmetic outcome was observed in patients with skin spacing ≥ 19 mm (50%) compared to patients with < 19 mm (11%; p = 0.087). At 1 year the rate of ‘good to excellent‘ cosmetic results was 84%. Significant changes in QoL were observed for emotional and social well-being between 3 and 12 months. At 24 months only emotional well-being subscore changes were statistically significant (p = 0.015). Param Conclusions: To our knowledge, this is the first study since the initial FDA clinical study showing the feasibility of MammoSite brachytherapy procedure as a sole therapy in highly selected patients older than 60 years. This is also the first report on QoL during and after APBI using HDR brachytherapy with a MammoSite device. The toxicity and cosmetic results are in the range of other series. Higher range of skin spacing allowed a significant reduction of the risk of telangiectasia. QoL evaluation indicate that baseline scores were satisfactory. Changes concerned mainly emotional and social well-being. No significant financial relationships to disclose.