Wilkinson John B, Chen Peter Y, Wallace Michelle F, Shah Chirag S, Benitez Pamela R, Martinez Alvaro A, Vicini Frank A
Provision Proton Therapy Center, Knoxville, TN.
Oakland University William Beaumont School of Medicine, Royal Oak.
Am J Clin Oncol. 2018 Oct;41(10):986-991. doi: 10.1097/COC.0000000000000402.
To report 6-year outcomes from a phase I/II trial using balloon-based brachytherapy to deliver APBI in 2 days.
A total of 45 patients with early-stage breast cancer received adjuvant APBI in 2 days with high-dose rate (HDR) brachytherapy totaling 2800 cGy in 4 fractions (700 cGy BID) using a balloon-based applicator as part of a prospective phase I/II clinical trial. All patients had negative margins and skin spacing ≥8 mm. We evaluated toxicities (CTCAE v3) as well as ipsilateral breast tumor recurrence (IBTR), regional nodal failure (RNF), distant metastasis, disease-free survival, cause-specific survival, and overall survival.
Median age and tumor size were 66 years old (48 to 83) and 0.8 cm (0.2 to 2.3 cm), respectively. Four percent of patients were N1 (n=2) and 73% were estrogen receptor (ER) positive (n=32). Median follow-up was 6.2 years (2.4 to 8.0 y). Nearly all toxicities at 6 years were grade 1 to 2 except 1 instance of grade 3 telangiectasia (2%). Eleven percent (n=5) of patients had chronic asymptomatic fat necrosis whereas asymptomatic seromas were noted on mammogram in 13% of cases (n=6). Cosmesis at last follow-up was good or excellent in 91% of cases (n=40) and fair in 9% (n=4). Two of the previously reported rib fractures healed with conservative measures. There were no IBTR or RNF (6 y IBTR/RNF rate 0%); however, 2 patients experienced distant metastasis (4% at 6 y). The 6-year actuarial disease-free survival, cause-specific survival, and overall survival were 96%, 100%, and 93%, respectively.
Hypofractionated 2-day APBI using brachytherapy resulted in excellent clinical outcomes with acceptable chronic toxicities.
报告一项I/II期试验的6年结果，该试验使用基于球囊的近距离放射疗法在2天内进行加速部分乳腺照射（APBI）。
作为一项前瞻性I/II期临床试验的一部分，共有45例早期乳腺癌患者在2天内接受了辅助性APBI，采用高剂量率（HDR）近距离放射疗法，共4次分割，总量2800 cGy（每日两次，每次700 cGy），使用基于球囊的施源器。所有患者切缘阴性，皮肤间距≥8 mm。我们评估了毒性（CTCAE v3）以及同侧乳腺肿瘤复发（IBTR）、区域淋巴结转移（RNF）、远处转移、无病生存期、病因特异性生存期和总生存期。
中位年龄和肿瘤大小分别为66岁（48至83岁）和0.8 cm（0.2至2.3 cm）。4%的患者为N1（n = 2），73%的患者雌激素受体（ER）阳性（n = 32）。中位随访时间为6.2年（2.4至8.0年）。6年时几乎所有毒性均为1至2级，1例3级毛细血管扩张除外（2%）。11%（n = 5）的患者有慢性无症状脂肪坏死，13%的病例（n = 6）在乳房X线检查中发现无症状血清肿。最后一次随访时，91%的病例（n = 40）美容效果良好或极佳，9%（n = 4）为中等。之前报告的2例肋骨骨折通过保守治疗愈合。无IBTR或RNF（6年IBTR/RNF率0%）；然而，2例患者发生远处转移（6年时为4%）。6年精算无病生存期、病因特异性生存期和总生存期分别为96%、100%和93%。
使用近距离放射疗法进行的2天超分割APBI产生了优异的临床结果，慢性毒性可接受。
