Patterns and prognosis of regional recurrence in nasopharyngeal carcinoma after intensity-modulated radiotherapy.

Abstract

OBJECTIVE:

We analyzed the patterns of lymph node (LN) failure and prognosis in patients with regional recurrent nasopharyngeal carcinoma (rNPC) alone after primary intensity-modulated radiotherapy (IMRT).

METHODS:

A total of 175 patients who were treated with IMRT between 2010 and 2015 and who experienced regional recurrence alone were included. Recurrent LNs were re-located in the initial pretreatment imaging and IMRT plan and failures were classified as in-field or out-field based on target volume delineation. All patients underwent curative salvage treatment. Independent prognostic factors for overall survival (OS) were selected by multivariate Cox analysis.

RESULTS:

Level IIb (49.1%, 86/175) was the most frequent recurrence site, followed by level IIa (36%), level III (18.9%), level IVa (12%), the retropharyngeal region (8%), level Va (6.9%), and the parotid region (6.9%). A total of 264 recurrent LNs were recorded: 149 (56.4%) were classified as in-field failure with a prescribed dose ≥66 Gy, 60 (22.7%) with 60 to <66 Gy, 32 (12.1%) with 50 to <60 Gy, and 23 (8.7%) as an out-field failure, which mainly occurred in the parotid region and level Ib. After a median follow-up of 52.8 months, the estimated 5-year OS rate was 66.9%. Multivariate analysis showed that age, plasma Epstein-Barr virus DNA level, extranodal extension, lower neck involvement, and parotid LN recurrence were independent prognostic factors of OS.

CONCLUSIONS:

In-field failure represented the main pattern of regional recurrence and out-field failure mainly occurred in the parotid gland and level Ib. Patients with regional rNPC alone had a good prognosis after salvage treatment.

• Authors: Xiao-Tang Xiao, Yi-Shan Wu, Yu-Pei Chen, Xu Liu, Rui Guo, Ling-Long Tang, Jun Ma, Wen-Fei Li
• Journal: Cancer medicine (Cancer Med) Vol. 12 Issue 2 Pg. 1399-1408 (01 2023) ISSN: 2045-7634 [Electronic] United States
• PMID: 35822664 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2022 The Authors. Cancer Medicine published by John Wiley & Sons Ltd.

Topics

• Humans
• Nasopharyngeal Carcinoma (radiotherapy, pathology)
• Radiotherapy, Intensity-Modulated (methods)
• Nasopharyngeal Neoplasms (pathology)
• Epstein-Barr Virus Infections (pathology)
• Herpesvirus 4, Human
• Neoplasm Recurrence, Local (pathology)
• Prognosis
• Follow-Up Studies
• Retrospective Studies
• Neoplasm Staging