Abstract
The prognostic value and staging category of parotid lymph node (PLN) metastasis in nasopharyngeal carcinoma (NPC) remain unknown. We retrospectively reviewed MRI scans and medical records for 1811 NPC patients who received intensity-modulated radiotherapy. The diagnosis of PLN metastasis was mainly based on MRI follow-up. Twenty-five positive PLNs in 21/1811 patients were identified; the incidence of PLN metastasis was 1.2%. PLN metastasis was significantly associated with advanced N-category and stage. Ten of the 21 patients received irradiation of the involved PLNs; the PLN recurrence rate was significantly higher for patients who received no irradiation; thus only patients with irradiated PLN were included in prognostic analyses. PLN metastasis was associated with significantly poorer progression-free survival, overall survival and distant metastasis-free survival (DMFS), but not regional or local relapse-free survival, in univariate analysis. In multivariate analysis, PLN metastasis was also significantly associated with poor DMFS. PLN involvement had a significantly higher hazard ratio (HR) for distant failure than N2 disease and similar HR to N3 disease. In conclusion, PLN metastasis is rare in NPC and was associated with similarly poor DMFS as N3 disease. PLN metastasis should be suspected in advanced nodal disease, but diagnosed with care before administering aggressive treatment.
Highlights
V, followed by level Ib and the supraclavicular nodes[2,3,4,5,6,7]
Of these 40 patients, only four underwent pretreatment fine-needle aspiration cytology (FNAC): one node was a metastatic parotid lymph nodes (PLNs), one node was reactive lymphoid hyperplasia, one node was basal cell adenoma and the other node was fibrous connective tissue hyperplasia; the three patients without PLN metastases were excluded from further analyses
25 PLN metastases were identified in 21/1811 patients (Fig. 1); the incidence of PLN metastasis was 1.2%
Summary
V, followed by level Ib and the supraclavicular nodes[2,3,4,5,6,7]. The parotid lymph nodes (PLNs), classified as level VIII in the latest International Consensus. The occurrence of PLN metastasis has been reported in several studies and is approximately 1%4–6,9–11 To the best of our knowledge, the prognostic significance of and clinical staging system for PLN metastasis have not been investigated in NPC due the low incidence PLN involvement. The diagnosis of PLN metastasis in NPC is mainly based on magnetic resonance imaging (MRI) and/ or fine-needle aspiration cytology (FNAC). Several studies have indicated that imaging during follow-up may be a reliable method to determine the final diagnosis of lymph node involvement[23,24,25]. The aim of the present study was to determine the prognostic value of and staging category for PLN metastasis in a large cohort of patients with NPC treated with IMRT based on MRI follow-up
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
