Lymph Node Staging of Oral and Maxillofacial Neoplasms in 31 Dogs and Cats

Abstract

A retrospective study was performed to report the histologic examination results of regional lymph nodes of dogs and cats with oral or maxillofacial neoplasms. Twenty-eight dogs and 3 cats were evaluated. Histologic examination results of standard and serial tissue sectioning of regional lymph nodes were recorded. When available, other clinical parameters including mandibular lymph node palpation, thoracic radiographs, and pre- and postoperative fine needle aspiration of lymph nodes were compared with the histologic results. Squamous cell carcinoma, fibrosarcoma, and melanoma were the most common neoplasms diagnosed in dogs. Squamous cell carcinoma and fibrosarcoma were diagnosed in cats. Of the palpably enlarged mandibular lymph nodes, 17.0% had metastatic disease histologically. Radiographically evident thoracic metastatic disease was present in 7.4% of cases. Preoperative cytologic evaluation of the mandibular lymph node based on fine needle aspiration concurred with the histologic results in 90.5% of lymph nodes examined. Postoperative cytologic evaluation of fine needle aspirates of regional lymph nodes concurred with the histologic results in 80.6% of lymph nodes examined. Only 54.5% of cases with metastatic disease to regional lymph nodes had metastasis that included the mandibular lymph node. Serial lymph node sectioning provided additional information or metastasis detection. Cytologic evaluation of the mandibular lymph node correlates positively with histology, however results may fail to indicate the presence of regional metastasis. Assessment of all regional lymph nodes in dogs and cats with oral or maxillofacial neoplasms will detect more metastatic disease than assessing the mandibular lymph node only.

Rib metastases from a non‐tonsillar squamous cell carcinoma in a dog

“…Fine needle aspiration of the regional lymph nodes has been shown to improve the detection of metastatic disease in palpable normal lymph nodes (Langenbach and others 2001). Moreover, cytology or histopathology of all three principal lymphocentrums of the head, mandibular, parotid and medial retropharyngeal lymph nodes, has been recommended to detect metastatic disease of the maxillofacial region which may be overlooked by examination of the mandibular lymph nodes alone (Smith 1995, Herring and others 2002). In retrospect, aspiration cytology of the mandibular lymph node, or excision of the regional lymph nodes draining the head should have been performed to aid prognostication and to determine the need for adjuvant therapy in the current case.…”

Investigation of the utility of lymph node fine‐needle aspiration cytology for the staging of malignant solid tumors in dogs

“…In a prospective study including 37 dogs and 7 cats diagnosed with a variety of tumors (16 carcinomas, 18 sarcomas, 7 mast cell tumors (MCTs), 2 melanomas, and 1 histiocytic sarcoma), the sensitivity and specificity of FNAC (obtained from 41 animals) for assessing regional LNs were 100% and 96%, respectively, with histopathology used as the gold standard . In another prospective study including 28 dogs and 3 cats with oral or maxillofacial neoplasms (10 squamous cell carcinomas, 6 fibrosarcomas, 5 melanomas, and 10 other tumors), the accuracy of FNAC for LN staging was 90.5% when compared with histopathology . In contrast, in a recent large retrospective study, the sensitivity and specificity of FNAC in the detection of LN neoplasia were 66.6% and 91.5%, respectively .…”

“…Only 2 relatively small prospective studies have assessed the accuracy of FNAC for LN staging in dogs, both finding good agreement with histopathology . A more recent, large retrospective study found that FNAC had poor sensitivity for detecting LN neoplasia; however, the authors did not design the study to assess FNAC in the setting of routine LN staging .…”

Dental and Oral Diseases

“…51 Oral examination focuses on the location, size, extent, and surface characteristics of the lesion, which may be smooth, irregular, pigmented, inflamed, ulcerated, bleeding, or necrotic. Abdominal ultrasound may be added in selected cases.…”