Yashar Catheryn, Khan Atif J, Chen Peter, Einck John, Poppe Matthew, Li Linna, Yehia Zeinab Abou, Vicini Frank A, Moore Dirk, Arthur Doug, Quinn T J, Kowzun Maria, Simon Laurie, Scanderbeg Daniel, Shah Chirag, Haffty Bruce G, Kuske Robert
UC San Diego/Moores Cancer Center, La Jolla, California; Bryn Mawr Hospital, Bryn Mawr, Pennsylvania.
Memorial Sloan Kettering Cancer Center, New York, New York.
Pract Radiat Oncol. 2023 Jul-Aug;13(4):314-320. doi: 10.1016/j.prro.2023.03.006. Epub 2023 May 1.
Shorter courses of breast radiotherapy are offered as an alternative to 4 weeks of whole-breast irradiation after lumpectomy, including brachytherapy. A prospective phase 2multi-institution clinical trial to study 3-fraction accelerated partial breast irradiation delivered by brachytherapy was conducted.
The trial treated selected breast cancers after breast-conserving surgery with brachytherapy applicators that delivered 22.5 Gy in 3 fractions of 7.5 Gy. The planning treatment volume was 1 to 2 cm beyond the surgical cavity. Eligible women were age ≥45 years with unicentric invasive or in situ tumors ≤3 cm excised with negative margins and with positive estrogen or progesterone receptors and no metastases to axillary nodes. Strict dosimetric parameters were required to be met and follow up information was collected from the participating sites.
Two hundred patients were prospectively enrolled; however, a total of 185 patients who were enrolled were followed for a median of 3.63 years. Three-fraction brachytherapy was associated with low chronic toxicity. There was excellent or good cosmesis in 94% of patients. There were no grade 4 toxicities. Grade 3 fibrosis at the treatment site was present in 1.7% and 32% percent had grades 1 or 2 fibrosis at the treatment site. There was 1 rib fracture. Other late toxicities included 7.4% grade 1 hyperpigmentation, 2% grade 1 telangiectasias, 1.7% symptomatic seromas, 1.7% abscessed cavities, and 1.1% symptomatic fat necrosis. There were 2 (1.1%) ipsilateral local recurrences, 2 (1.1%) nodal recurrences and no distant recurrences. Other incidents included one contralateral breast cancer and 2 second malignancies (lung).
Ultra-short breast brachytherapy is feasible and has excellent toxicity and could be an alternative to standard 5-day, 10 fraction accelerated partial breast irradiation in eligible patients. Patients from this prospective trial will continue to be followed to evaluate long-term outcomes.
在保乳手术后，提供短疗程的乳房放疗作为4周全乳照射（包括近距离放疗）的替代方案。开展了一项前瞻性2期多机构临床试验，以研究通过近距离放疗进行的3分次加速部分乳腺照射。
该试验使用近距离放疗施源器对保乳手术后选定的乳腺癌进行治疗，分3次给予22.5 Gy，每次7.5 Gy。计划靶体积为手术腔外1至2厘米。符合条件的女性年龄≥45岁，患有单中心浸润性或原位肿瘤，肿瘤切除后≤3厘米，切缘阴性，雌激素或孕激素受体阳性，腋窝淋巴结无转移。要求满足严格的剂量学参数，并从参与研究的机构收集随访信息。
前瞻性纳入了200例患者；然而，总共185例入组患者的中位随访时间为3.63年。3分次近距离放疗的慢性毒性较低。94%的患者美容效果良好或优秀。无4级毒性反应。治疗部位3级纤维化的发生率为1.7%，32%的患者治疗部位有1级或2级纤维化。发生1例肋骨骨折。其他晚期毒性反应包括7.4%的1级色素沉着、2%的1级毛细血管扩张、1.7%的有症状血清肿、1.7%的脓肿腔和1.1%的有症状脂肪坏死。有2例（1.1%）同侧局部复发、2例（1.1%）区域复发，无远处复发。其他事件包括1例对侧乳腺癌和2例第二原发恶性肿瘤（肺癌）。
超短程乳房近距离放疗是可行的，毒性良好，对于符合条件的患者可作为标准的5天10分次加速部分乳腺照射的替代方案。该前瞻性试验的患者将继续接受随访以评估长期结果。
