目的:本研究的目的是确定胸部预处理诊断计算机断层扫描(CT)上的腋窝淋巴结,以确定其相对于放射疗法肿瘤学组(RTOG)乳腺癌放射治疗计划图集定义的解剖腋窝边界的位置。
方法:对30例临床累及淋巴结的乳腺癌患者进行治疗前诊断性CT胸部扫描与模拟CT融合。腋窝水平I的轮廓,II,并根据RTOG指南进行III。对于每个水平,从远端肿瘤区域到解剖边界进行6个维度的测量。
结果:在30名患者中,100%,93%,37%的人有I级的临床参与,II,III,分别。平均清扫淋巴结数为13.6。最大淋巴结的平均大小为2.4cm。23%的患者可见囊外延伸。在97%的患者中,受累淋巴结的一个方面位于水平的解剖边界之外。在80%和83%的患者中,肿瘤延伸可见于颅外(1.78±1.0cm;范围,0.28-3.58厘米)和前部(1.27±0.92厘米;范围,0.24-3.58厘米)一级边界,分别。在80%的患者中,在II级尾边界外可见肿瘤扩展(1.36±1.0cm,范围,0.27-3.86厘米),0%至33%的患者的肿瘤扩展到所有级别的其余边界之外。
结论:为了覆盖I级颅骨和前边界的95%的淋巴结,额外的临床目标体积边缘为3.78cm和3.11cm,分别,是必要的。RTOG指南可能不足以覆盖正在接受新辅助化疗的临床淋巴结受累患者的腋窝疾病。不完全腋窝解剖,或调强放射治疗。在患者的预处理诊断CT胸部扫描,肿瘤勾画应考虑与模拟CT融合。
OBJECTIVE: The purpose of this study was to identify the axillary lymph nodes on pretreatment diagnostic computed tomography (CT) of the chest to determine their position relative to the anatomic axillary borders as defined by the Radiation Therapy Oncology Group (RTOG) breast cancer atlas for radiation therapy planning.
METHODS: Pretreatment diagnostic CT chest scans available for 30 breast cancer patients with clinically involved lymph nodes were fused with simulation CT. Contouring of axillary levels I, II, and III according to the RTOG
guidelines was performed. Measurements were made from the area of distal tumor to the anatomic borders in 6 dimensions for each level.
RESULTS: Of the 30 patients, 100%, 93%, and 37% had clinical involvement of levels I, II, and III, respectively. The mean number of lymph nodes dissected was 13.6. The mean size of the largest lymph node was 2.4 cm. Extracapsular extension was seen in 23% of patients. In 97% of patients, an aspect of the involved lymph node lay outside of the anatomic border of a level. In 80% and 83% of patients, tumor extension was seen outside the cranial (1.78 ± 1.0 cm; range, 0.28-3.58 cm) and anterior (1.27 ± 0.92 cm; range, 0.24-3.58 cm) borders of level I, respectively. In 80% of patients, tumor extension was seen outside the caudal border of level II (1.36 ± 1.0 cm, range, 0.27-3.86 cm), and 0% to 33% of patients had tumor extension outside the remaining borders of all levels.
CONCLUSIONS: To cover 95% of lymph nodes at the cranial and anterior borders of level I, an additional clinical target volume margin of 3.78 cm and 3.11 cm, respectively, is necessary. The RTOG
guidelines may be insufficient for coverage of axillary disease in patients with clinical nodal involvement who are undergoing neoadjuvant chemotherapy, incomplete axillary dissection, or treatment with intensity modulated radiation therapy. In patients with pretreatment diagnostic CT chest scans, fusion with simulation CT should be considered for tumor delineation.