The Development Of An Indirect CT Lymphography Protocol For Sentinel Lymph Node Detection In Head And Neck Cancer and Comparison to Other Sentinel Lymph Node Mapping Techniques

Identification of metastatic disease critically impacts the care and prognosis of patients with neoplasia. Multiple techniques exist for identifying the sentinel or first lymph node(s) that receive draining tumor lymph. Identification of the sentinel lymph node enables accurate tissue sampling for determination of lymphatic metastasis. The aims of this study were to develop a CT protocol for identifying the sentinel lymph node in dogs with tumors of the head and neck. In addition, indirect CT lymphography was compared to lymphoscintigraphy and vital dye injection to determine which technique more reliably identified the sentinel lymph node. CT indirect lymphography using intratumoral injection of iodinated contrast identified draining lymphatic vessels in 8 of 18 dogs and identified the sentinel lymph node in 5 of 18 dogs. CT indirect lymphography employing four quadrant peritumoral injection of iodinated contrast identified draining lymphatic vessels in 18 of 20 dogs and identified the sentinel lymph node in 11 of 20 dogs. Vital dye injection and lymphoscintigraphy identified the sentinel lymph node in 17 of 18 and 20 of 20dogs, respectively. Identified sentinel lymph nodes were either ipsilateral or bilateral to the primary tumor. Both CT techniques were found to be safe and simple. Peritumoral injection has the greatest promise for the detection of sentinel lymph nodes in various head and neck cancers using CT, while lymphoscintigraphy had the greatest success of the compared techniques. This article is protected by copyright. All rights reserved.