Sentinel lymph nodes for canine oral tumors

long haired white dog walkingStudy Title: Clinical feasibility and accuracy of indirect computed tomography lymphangiography for identification of metastasis within the sentinel lymph node of dogs with spontaneously arising oral neoplasia
Current Status: Open and enrolling
Principal Investigator: Stephanie Goldschmidt, BVM&S, DAVDC
Contact: Dr. Stephanie Goldschmidt, golds245@umn.edu

Purpose

This is a pilot study evaluating the use of sentinel lymph node mapping in dogs with oral tumors. Evaluation of the local draining lymph nodes for presence of metastasis (cancer spread) is a critical step in the oncologic work-up, as it can affect overall prognosis and invariably influences treatment recommendations.

The ideal lymph node to sample for presence of metastasis is the sentinel lymph node. The sentinel lymph node is defined as the first lymph node that drains the primary tumor. However, currently in dogs sentinel lymph node mapping is not performed as there is no validated technique. Thus, the gold standard treatment recommendation with aggressive oral tumors is to remove all the possible draining lymph nodes, so that all prognostic information can be fully gathered and all potential tumor cells can be removed.

Moving forward, the use of more reliable methods to identify the sentinel lymph nodes in veterinary patients will improve patient-specific treatment and avoid unnecessary lymph node removal. A proof of concept study recently demonstrated the effectiveness of a sentinel lymph node mapping technique (CT- lymphangiography) in the canine head. However, current data still leaves a critical knowledge gap surrounding the true use of this technique for the prediction of lymph node metastasis in oral tumors. The aim of this study is to perform CT-lymphangiography on oral tumors prior to removal and to correlate lymph node imaging criteria to pathological diagnosis (metastatic, reactive, normal). If this technique is successful, it could drastically change predictions of metastasis in our canine patients.


Eligibility

Eligible dogs include patients with aggressive tumors in the head or neck that are scheduled for CT scan of the head.

If you elect to be in the study then CT-lymphangiography (sentinel lymph node mapping) will be included in your dog's CT scan. After imaging, the draining lymph nodes will be surgically removed to evaluate for presence of metastasis. As discussed above, based on our current knowledge in veterinary patients, this is the gold standard recommendation for staging/treatment of aggressive oral tumors. Removal of the draining lymph nodes can be performed at the time of the CT scan or at the time of surgical removal of the oral tumor.

Procedures

A: After traditional CT scan, CT-lymphangiography will be performed. This involves injection of contrast at the tumor site to identify which lymph node this contrast drains to (the sentinel lymph node).

B: Removal of the mandibular and retropharyngeal lymph nodes will be performed through a central midline incision or two small bilateral incisions over the lymph nodes

Costs of the study

There will be no additional costs associated with the participation in the study. The cost of the sentinel lymph node mapping, surgery to remove the lymph nodes, additional anesthesia costs associated with these procedures, and pathology of the lymph nodes will be covered. However, you will be responsible for the cost of the traditional CT scan of the head as well as any curative intent surgery for the primary tumor that you choose to pursue.