CT三维重建在评估乳腺癌前哨淋巴结状态及其引流通路中的应用研究

目的　探讨利用CT三维重建的方法在评估乳腺癌前哨淋巴结（SLN）状态及其引流通路中的应用价值。方法　对确诊为乳腺癌拟行前哨淋巴结活检（SLNB）或腋窝淋巴结清扫（ALND）的23例患者行CT淋巴管造影（CT-LG），图像经3D容积重建后显示SLN及其引流淋巴管，通过SLN的影像学特征如淋巴结的形态及充盈情况等来评估其转移情况，并与术后病理结果作对比；将CT-LG所显示的SLN及其相连的淋巴管与SLNB术中解剖的SLN及其连接的淋巴管进行对比分析，验证CT三维重建的临床应用价值。结果　20例（86.9%）患者的SLN被检出；SLNB检出SLN数量显著高于CT-LG（Z=3.568，P＜0.01）。通过CT-LG在术前发现1枚非常规引流通路SLN，由乳晕处淋巴管丛发出，通过腺体层进入乳房后间隙；CT-LG所显示的34枚淋巴结中病理阴性26枚，其中有20枚淋巴结表现为均匀充盈，6枚表现为充盈缺损；病理阳性的8枚均表现为充盈缺损；在病理阳性SLN淋巴结充盈缺损比例高于病理阴性SLN（P＜0.01）。结论　CT三维重建有助于SLN的精准定位，也可以发现非常规引流通路的SLN，对于影像学表现为充盈缺损的淋巴结应考虑有肿瘤细胞浸润。

Application of CT three-dimensional reconstruction in the assessment of sentinel lymph node status and drainage pathways in breast cancer

Objective　To explore the application value of using CT three-dimensional (3D) reconstruction method in assessing the status of the sentinel lymph node (SLN) and its drainage pathway in breast cancer. Methods　Computed tomography lymphodography (CT-LG) was performed in 23 patients who were diagnosed with breast cancer underwent sentinel lymph node biopsy (SLNB) or axillary lymph node dissection (ALND). After 3D volume reconstruction, the image showed SLN and the drainage lymphatic vessels. The metastasis of the SLN was evaluated by imaging features, such as the morphology and filling of lymph nodes, and compared with the postoperative pathological results. SLN and its connected lymphatic vessels displayed by CT-LG were compared with the SLN and its connected lymphatic vessels dissected during SLNB operation to further verify the clinical application value of CT 3D reconstruction. Results　A total of 20 patients were successfully detected, with a detected rate of 86.9%. The number of SLN detected by SLNB was significantly higher than that detected by CT-LG (Z=3.568, P＜0.01). An unconventional drainage pathway SLN was found before the operation through CT-LG technology, which was sent out from the lymphatic plexus in the areola and entered the posterior breast space through the glandular layer. Among 34 lymph nodes displayed by CT-LG, 26 were pathologically negative, of which 20 lymph nodes showed uniform filling, 6 showed filling defects, and 8 were pathologically positive, all showing filling defects. The proportion of filling defects in pathologically positive SLN lymph nodes was higher than that of pathologically negative SLN (P＜0.01). Conclusion　The CT 3D reconstruction method is helpful for the precise positioning of sentinel lymph nodes, and it can also find the SLN of unconventional drainage pathways. For imaging manifestations of filling defects, tumor cell infiltration should be considered.