Clinical, ultrasound and histopathological correlation of clinically N0 neck nodes in patients with cancers of the pharynx and larynx

Background: The presence of metastatic cervical adenopathy is essential for treatment planning and prognosis assessment. Treatment of patients with head and neck cancer with clinically negative cervical lymphadenopathy (N0) remains controversial. Neck palpation, as the method used in tumor, node, metastasis (TNM) staging, has limitations and can provide false negative results in some cases. Lymph node metastases are associated with a reduced survival rate but at the same time, neck dissection for the patient with N0 neck is not without risks or complications. Objectives: In prospective study, we compared palpation, ultrasonography (US) examination of the neck and histopathological examination in patients with cancers of the pharynx and larynx. Patients, Materials and Methods: Forty-six patients with cancers of the pharynx and larynx that presented with a N0 neck were prospectively analyzed. They were divided in two groups: 23 patients operated with an external approach including the control of the lymph node areas, and a second group of 23 patients operated using endoscopy and carbon dioxide (CO2) laser, no neck dissection – “watchful waiting policy”. All patients have had a flexible endoscopy of the pharynx and larynx, US of the neck and all received surgical treatment for their primary tumor. Imaging was performed in selected cases. All the removed lymph nodes were sent for histopathology. US was also used as a follow-up method. The US features of the examined lymph nodes were: diameters [longitudinal (L) and transverse (T)]; the ratio of the two diameters (L/T); shape; lymph node area; central hypodensity; regular/irregular margins; aspect (homogeneous or not). Results: US has detected 25 lymph nodes in the open surgery group and intraoperatively, we excised 31 (sensitivity of 80.6%). Ten lymph nodes showed metastases, with 100% accuracy of US, which have been confirmed both pathologically and immunohistochemically. US in the second group – patients treated with CO2 laser – detected at four patients 10 cervical lymph nodes that did not presented any malignant features. At recurrence alone, the US confirmed 100% presence of nodes metastases. Conclusions: US was superior to palpation and this method can be recommended as a diagnostic tool in preoperative assessment of patients without palpable metastasis (N0).