Ability of Positron Emission Tomography to Detect Residual Neck Node Disease in Patients With Head and Neck Squamous Cell Carcinoma After Definitive Chemoradiotherapy

Abstract

To report our experience using the neck examination, computed tomography (CT), and positron emission tomography (PET) to clinically evaluate node-positive patients with head and neck squamous cell cancer for residual neck node disease after definitive chemoradiotherapy. Retrospective review of all Cleveland Clinic patients with head and neck squamous cell cancer and N2 or N3 neck node involvement at presentation who were treated with definitive concurrent chemoradiotherapy and who underwent clinical restaging after treatment using the neck examination, CT, and PET. Tertiary care referral institution. Forty-eight patients with 72 positive necks at diagnosis were followed up for a median of 20 months. Palpable nodes on examination, nodes larger than 1 cm, nodes with central necrosis on CT, or any hypermetabolic lymph nodes on PET were considered clinical evidence of residual nodal disease. The true rate of pathologic involvement was determined by histologic examination after planned neck dissection or if regional recurrence developed. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were calculated for all 3 clinical assessment tools. Planned neck dissection was performed in 33 necks and was positive for residual neck node disease in 5 necks. A delayed neck dissection was performed in 5 necks and was positive in 3 necks. The positive predictive value was low for all 3 clinical assessment tools. The addition of PET did not significantly improve the negative predictive value or positive predictive value of CT and the clinical examination. Residual neck node disease after definitive chemoradiotherapy was infrequent and was not well predicted by PET. A positive PET finding in this setting is of little utility. Although a negative PET finding was highly predictive for control of neck disease after chemoradiotherapy, it added little to the clinical neck examination and CT.