The true malignancy rate in 135 patients with preoperative diagnosis of a lateral neck cyst

OBJECTIVE In this study, the true malignancy rate in 135 patients with a preoperative tentative diagnosis of a lateral neck cyst (LNC) was assessed. Furthermore, the sensitivity and specificity of fine needle aspiration of suspected LNC were evaluated and the diagnostic delay was analyzed. STUDY DESIGN This study was retrospective in design and included all patients who had undergone surgery for a suspected LNC in four secondary hospitals in the eastern regions of Denmark during the period of 2009 to 2012. METHODS One hundred thirty-five patients were identified and included by means of a search strategy for NOMECO surgical procedure codes KENB40A+B in the electronic surgical booking systems. Because the procedure codes also include median neck cysts and fistulas, the latter were excluded manually. RESULTS Of the 135 patients preoperatively diagnosed with LNC, a malignant postoperative histopathological diagnosis was revealed in 19 patients (14.4%). Of these, three individuals were between 35 to 40 years of age. In 17 cases, preoperative fine-needle aspiration biopsy showed benign cytology, whereas histopathology postoperatively proved to be malignant. This renders a sensitivity of 88.8% and a specificity of 60.0% for fine needle aspiration biopsy with regard to LNC diagnostics. CONCLUSION This study suggests that, for patients older than 35 years, a cystic lateral neck mass should be considered potentially malignant; by contrast, LNC is a diagnosis of exclusion. Any delay in treatment should be avoided until final histopathological diagnosis has been obtained. Arguably, all patients older than 35 years with a cystic lesion laterally on the neck should be included in the fast-track cancer referral program. LEVEL OF EVIDENCE 2b.