RESUMEN
PURPOSE: The aim of this study is to estimate the incidence and clinical impact of lymph node micrometastases in hypopharyngeal squamous cell cancer (HSCC). MATERIALS AND METHODS: In this retrospective study, we enrolled 58 patients who have undergone surgery for HSCC (between January 2004 and January 2011). Pharyngolaryngectomy and oesophagectomy with selective bilateral neck dissection was performed in all patients. Based on standard histological examination, 17 patients met N0 and 8 patients met N1 criteria and were further evaluated for the presence of micrometastases and isolated tumour cells (ITC). Following immunohistochemical analysis, the patients were grouped according to the presence of micrometastases and ITCs. RESULTS: In the pN0 group, cytokeratin-positive cells were detected in five patients, and they were marked as N0/CK+. Among these five patients, two were found to harbour micrometastases and ITCs, whilst in three, only ITCs were found. Two patients (11.75 %) were upstaged to pN1. The patients marked as N0/CK+ had a statistically significant worse overall survival rates than pN0 patients with tissue samples read as negative for cytokeratin immunostaining (p = 0.019, p < 0.05). In the pN1 group, cytokeratin-positive cells were detected in two patients, with one patient showing micrometastases and ITC, and the other showing ITC only. One patient was upstaged to pN2. CONCLUSION: Patients with lymph node micrometastases and ITC had worse overall survival rates, which may indicate that more aggressive post-operative treatment regimens should be considered for these HSCC patients.