下咽癌淋巴引流的活体显像研究

Imaging in Vivo of Lymph Drainage in Hypopharyngeal Cancer

目的:探讨下咽癌颈淋巴结转移时肿瘤区域引流淋巴结的活体显像方法,从肿瘤活体淋巴引流的角度观察下咽癌前哨淋巴结和颈淋巴结转移的方式,为颈淋巴结清扫术提供指导信息。方法:在表面麻醉和喉内镜引导下,用特制的注射针将99mTc标记的人球蛋白注入20例下咽癌的肿瘤部位,在注射后不同时间采用SPECT扫描观察放射性核素通过淋巴扩散的过程及其在引流淋巴结内的浓集,以明确前哨淋巴结的位置和肿瘤颈淋巴结引流过程。同时对颈淋巴清扫标本进行病理检查。结果:20例肿瘤引流淋巴结均获得满意活体显像,显像的淋巴结最大3.5cm,最小1.0cm;12例梨状窝癌的颈部引流淋巴结位于肿瘤侧,其余8例中线结构的肿瘤颈部引流淋巴结均具有明显的优势偏向,即单侧颈部引流现象,没有出现双侧对称引流的病例。20例肿瘤引流淋巴结主要分布在II、III、IV区,未发现I区和V区显像的淋巴结。术后病理证实20例中有16例发现病理阳性淋巴结,且均位于引流优势侧,未出现对侧和双侧颈淋巴结转移的病例。结论:无论是中线结构或偏中线结构的下咽部癌肿,其向颈部的淋巴引流具有明显的优势偏向特点,术前进行引流淋巴结的活体显像对预测肿瘤转移部位和有目的地进行择区性颈淋巴结清扫术具有重要意义。

Objective:To investigate the in vivo imaging method for demonstrating draining lymph nodes of tumor area in lymphatic metastasis with hypopharyngeal cancer,and to observe the modes of lymphatic metastasis in the sentinel lymph nodes so as to offer reference to surgical clearance of lymph nodes.Methods:Twenty patients with tumor including 12 cases of pyriform sinus cancers and 8 cases of posterior hypopharyngeal wall cancers were recruited in this study.With the assistance of endo-laryngoscope, 99mTc-labeled human globulin was injected into the primary tumors site under the topical anesthesia,and the diffusion and gathering of the radioisotope in the neck nodes was monitored by SPECT at different time intervals.The status of cervical lymph node metastasis was confirmed by postoperative pathological examination of the neck dissected specimens.Results:Satisfactory imaging of the tumor draining lymph nodes was achieved in all of the 20 patients.The size of the revealed lymph node ranged from 1.0 cm to 3.5 cm.In 12 patients with carcinoma at the pyriform sinus,the drainage lymph nodes were confined to the ipsilateral side of the neck.For other 8 cases with midline-situated tumors,there was predominance for these tumors to drain to lymph nodes of the unilateral neck.No symmetrical lymphatic drainage of tumors to the bilateral sides of neck was found.Lymph nodes in levels Ⅱ,Ⅲ and IV were the main destinations of lymphatic drainage for cancers in the hypopharyngeal regions.Positive lymph node for 99mTc-labeled human globulin was found in 16 cases,all allocated in the drainage side.No contra lateral or bilateral metastasis was observed.Conclusions:There was preponderance for unilateral neck node drainage and metastasis both in midline situated and in paramedially located hypopharyngeal cancers.Preoperative imaging of drainage lymph nodes is helpful in predicting and purposely removal of the metastatic lymph nodes in the neck.