Assessment Of Cervical Lymph Nodes Metastasis Using Interstitial MR Lymphography With C/Gd Nanocomposite In A Rabbit Tongue Cancer Model

PURPOSE: To investigate the value of novel imaging agent C/Gd nanocomposite interstitial magnetic resonance lymphography(IMRLG)in the diagnosis of cervical sentinel lymph node metastasis in a rabbit model of VX2 tongue cancer.METHODS: VX2 cancer tissue blocks were implanted into the left ventral submucosa of tongues in 16 healthy New Zealand white rabbits.After 25 days of implanting VX2,0.2 m L of contrast agent C/Gd nanocomposite were injected into bilateral submucosa mucosa of rabbits on both sides.MR lymphography was performed at 5min,10 min,15min,20 min,30min,40 min and 24 hour after injection.The signal enhancement rate(E %)was calculated,the sentinel lymph nodes was located and the characteristics of the lymphatic system was observed.After 24 hours of injecting contrast agent,0.2 m L of methylene blue were injected into the bilateral submucosa mucosa for lymph staining.Subsequently,the cervical lymph nodes were dissected and histopathological examinations were performed.SPSS19.0 software package was used to analyze the data.RESULTS: Sixteen rabbit models with tongue transplanted tumor were successfully established.The cervical lymph node metastases were found in 16 rabbits.E% had significant difference between the tumor side and the control side in ten minutes after injection of the contrast agent(p<0.05).IMRLG showed 18 metastatic nodes.Pathological examination indicated that 17/18 were positive,yielding a success rate of 94.45%(17/18).There was no significant difference between the two methods for diagnosing SLN metastasis(p>0.05).CONCLUSIONS: IMRLG by C/Gd nanocomplexes can be used to accurately determine the status of sentinel lymph node,which effectively provides a new way for detecting metastasis of lymph node of carcinoma of tongue.