The development of an indirect computed tomography lymphography protocol for sentinel lymph node detection in head and neck cancer and comparison to other sentinel lymph node mapping techniques

Abstract

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 tumour 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 computed tomography (CT) protocol for identifying the sentinel lymph node in dogs with tumours 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 eight of 18 dogs and identified the sentinel lymph node in five of 18 dogs. CT indirect lymphography employing fourquadrant 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 20 dogs, respectively. Identified sentinel lymph nodes were either ipsilateral or bilateral to the primary tumour. 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.

Determining agreement between preoperative computed tomography lymphography and indocyanine green near infrared fluorescence intraoperative imaging for sentinel lymph node mapping in dogs with oral tumours

“…SLN mapping is standard of care in human medicine for breast cancer, melanoma, and head and neck cancers 14‐16 . Various SLN mapping techniques have been described in human and veterinary medicine including blue dyes, 17‐20 lymphoscintigraphy, 11,18,20‐22 indirect radiographic lymphography, 23,24 indirect computed tomographic lymphography (CTL), 4,5,25‐30 and near infrared fluorescence imaging (NIRF) 31‐34 . A combined pre and intraoperative approach to SLN mapping has been suggested to optimize the accuracy for SLN detection 5,29 .…”

“…These techniques are non‐invasive, simple and rapid to perform, and exhibit minimal to no adverse effects. In veterinary medicine, a limited number of studies have assessed the use of indirect CTL, 4,5,25‐27 ICG NIRF, 31,32 and blue dyes 17,23 individually, however, there are no studies investigating the utility of these techniques in combination for SLN mapping in clinical patients.…”

Contrast‐enhanced ultrasound for sentinel lymph node mapping in the routine staging of canine mast cell tumours: A feasibility study

“…The use of computed-tomography (CT) SLN mapping is mainly restricted to Japan in human oncology, 17 but is becoming a very popular technique among veterinarians. [18][19][20][21][22] The main advantages being the wide availability of CT, the ability to visualize an entire area at the same time, and to perform 3D-reconstructions. Disadvantages are the necessity for deep sedation or general anaesthetic, cost, risk of adverse reactions to the iodinated contrast and its possible accumulation within the injected tissues and associated LNs for a prolonged period of time, 23 difficulty in determining the ideal time to scan, and in complying with the As Low As Reasonably Achievable radiation safety principle.…”

New Developments in Imaging for Sentinel Lymph Node Biopsy in Early-Stage Oral Cavity Squamous Cell Carcinoma

“…For reviewing the application of CT lymphography in early-stage OSCC, the systematic literature search led to retrieval of 112 PubMed indexed articles for CT lymphography, of which 17 were considered relevant [ 26 , 27 , 28 , 29 , 30 , 31 , 40 , 41 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 ]. Of these 17 articles, 11 were animal studies [ 40 , 41 , 64 , 65 , 66 , 67 , 68 , 69 , 70 , 71 , 72 ]. Cross-reference did not lead to any additional relevant articles.…”

“…This paper reviewed new developments in preoperative SLN imaging techniques in patients with early-stage OSCC. None of the included clinical studies contradicted outcomes or clinical translation predictions from corresponding animal studies, in regard of SLN identification using these novel techniques [ 22 , 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 42 , 43 , 44 , 45 , 46 , 50 , 51 , 64 , 66 , 67 , 69 , 70 , 71 , 72 ]. The overall reported rate of patients in which SLNs were identified using the presented techniques ranged from 89–100%.…”