Initial radiation experience evaluating early tolerance and toxicities in patients undergoing accelerated partial breast irradiation using the Contura Multi-Lumen Balloon breast brachytherapy catheter

Abstract

PurposeWe reviewed our institution's experience treating patients with the Contura Multi-Lumen Balloon (SenoRx, Inc., Irvine, CA) breast brachytherapy catheter to deliver accelerated partial breast irradiation. Methods and MaterialsForty-one patients treated with breast-conserving therapy received adjuvant radiation using the Contura catheter (34Gy in 3.4Gy fractions). Thirteen patients had Stage 0, 21 had Stage I, and 7 had Stage II breast cancer. Median followup was 8 months (range, 1–17). ResultsMedian, minimum skin spacing was 10mm (range, 2–17). Median, maximum skin doses (% of prescribed dose [PD]) were 99.7 (range, 57.1–124.1). Eight patients were treated with a skin spacing ≤5mm and 2 had a spacing of 2mm. Median, maximum rib doses were 102.6% of PD (10.0–187.7), and the median percentage of the planning target volume for evaluation (PTV_EVAL) receiving 95% of the PD was 98.8 (range, 79.4–107.4). The median volume receiving 200% of the PD was 5.7cc (range, 1.3–9.9). The percentage of patients with excellent/good cosmetic results at 6 months (n=15) and 12 months (n=12) was 100%. Patient tolerance was assessed on a scale 0–10 (0=no pain, 10=requiring narcotic analgesics). In 37 out of 38 patients, pain was graded ≤3 at the time of catheter insertion. Four breast infections (11%) and one transient symptomatic seroma (3%) developed. ConclusionAdjuvant accelerated partial breast irradiation using the Contura Multi-Lumen Balloon catheter exhibited similar toxicities to standard single lumen balloon brachytherapy with improvements in dosimetric capabilities (i.e., reduced skin and rib doses and improved PTV_EVAL coverage).