Brown Andrea, Buss Elizabeth J, Chin Christine, Liu Gaotong, Lee Shing, Rao Roshni, Taback Brett, Wiechmann Lisa, Horowitz David, Choi Julie C, Katz Leah M, Connolly Eileen P
Department of Radiation Oncology, Columbia University Irving Medical Center, New York, NY, United States.
Department of Biostatistics, Columbia University Mailman School of Public Health, New York, NY, United States.
Front Oncol. 2022 Jun 29;12:788213. doi: 10.3389/fonc.2022.788213. eCollection 2022.
PURPOSE/OBJECTIVE: We present our single-institution experience in the management of invasive breast cancer with targeted intraoperative radiotherapy (TARGIT-IORT), focusing on patient suitability for IORT determined by the American Society for Radiation Oncology (ASTRO) Accelerated Partial Breast Irradiation (APBI) consensus guidelines.
MATERIALS/METHODS: We identified 237 patients treated for biopsy-proven early-stage invasive breast cancer using low energy x-ray TARGIT-IORT at the time of lumpectomy between September 2013 and April 2020 who were prospectively enrolled in an institutional review board (IRB) approved database. We retrospectively reviewed preoperative and postoperative clinicopathologic factors to determine each patient's ASTRO APBI suitability (suitable, cautionary or unsuitable) according to the 2017 consensus guidelines (CG). Change in suitability group was determined based on final pathology. Kaplan-Meier methods were used to estimate the survival probability and recurrence probability across time.
237 patients were included in this analysis, based on preoperative clinicopathologic characteristics, 191 (80.6%) patients were suitable, 46 (19.4%) were cautionary and none were deemed unsuitable. Suitability classification changed in 95 (40%) patients based on final pathology from lumpectomy. Increasing preoperative lesion size or a body mass index (BMI) ≥ 30 kg/m were significant predictors for suitability group change. Forty-one (17.3%) patients received additional adjuvant whole breast radiotherapy after TARGIT-IORT. At a median follow up of 38.2 months (range 0.4 - 74.5), five (2.1%) patients had ipsilateral breast tumor recurrences (IBTR), including two (0.8%) true local recurrences defined as a recurrence in the same quadrant as the initial lumpectomy bed with the same histology as the initial tumor. IBTR occurred in 1/103 (0.09%) patient in the post-op suitable group, 4/98 (4.08%) patients in the post-op cautionary group, and no patients in the post-op unsuitable group. At 3-years, the overall survival rate was 98.4% and the local recurrence free survival rate was 97.1%.
There is a low rate of IBTR after TARGIT-IORT when used in appropriately selected patients. Change in suitability classification pre to postoperatively is common, highlighting a need for further investigation to optimize preoperative patient risk stratification in this setting. Patients who become cautionary or unsuitable based on final pathology should be considered for additional adjuvant therapy.
目的/目标：我们介绍了我们单机构使用术中靶向放疗（TARGIT-IORT）治疗浸润性乳腺癌的经验，重点关注根据美国放射肿瘤学会（ASTRO）加速部分乳腺照射（APBI）共识指南确定的适合IORT的患者。
材料/方法：我们确定了2013年9月至2020年4月期间在保乳手术时使用低能X线TARGIT-IORT治疗活检证实的早期浸润性乳腺癌的237例患者，这些患者被前瞻性纳入机构审查委员会（IRB）批准的数据库。我们回顾性分析术前和术后的临床病理因素，根据2017年共识指南（CG）确定每位患者的ASTRO APBI适用性（适合、警示或不适合）。根据最终病理确定适用性组的变化。采用Kaplan-Meier方法估计不同时间的生存概率和复发概率。
本分析纳入237例患者，根据术前临床病理特征，191例（80.6%）患者适合，46例（19.4%）为警示性，无患者被认为不适合。根据保乳手术的最终病理，95例（40%）患者的适用性分类发生了变化。术前病变大小增加或体重指数（BMI）≥30 kg/m²是适用性组变化的重要预测因素。41例（17.3%）患者在TARGIT-IORT后接受了额外的辅助全乳放疗。中位随访38.2个月（范围0.4 - 74.5个月），5例（2.1%）患者发生同侧乳腺肿瘤复发（IBTR），包括2例（0.8%）真正的局部复发，定义为在与初始保乳手术床相同象限且组织学与初始肿瘤相同的复发。IBTR发生在术后适合组的1/103（0.09%）患者、术后警示组的4/98（4.08%）患者，术后不适合组无患者发生。3年时，总生存率为98.4%，局部无复发生存率为97.1%。
在适当选择的患者中使用TARGIT-IORT后，IBTR发生率较低。术前至术后适用性分类的变化很常见，这突出表明需要进一步研究以优化这种情况下的术前患者风险分层。根据最终病理变为警示性或不适合的患者应考虑额外的辅助治疗。
