Head and Neck Cancer
PV QA 2 - Poster Viewing Q&A 2
Purpose/Objective(s): The 8th edition of UICC/AJCC staging system for nasopharyngeal carcinoma (NPC) has been validated to have a better prognostication than the 7th edition in endemic areas. However, validation studies from non-endemic areas are limited. We retrospectively evaluated the new edition of staging system for NPC patients from non-endemic areas (Western China) who were treated with intensity-modulated radiotherapy (IMRT).
Materials/Methods: Between July 2011 and December 2013, a total of 494 patients with newly diagnosed, non-metastatic NPC treated with IMRT in Sichuan Cancer Hospital were included. Overall survival (OS), progression-free survival (PFS), distant metastasis-free survival (DMFS) were calculated with the Kaplan-Meier method, and differences were compared by using the log-rank test. Akaike information criterion (AIC) and Harrell's concordance index (c-index) were calculated to compare the performance of various staging systems.
Results: The median age was 47 years (range, 14-83 years) with a male-to-female ratio of 1.9 to1 (325:169). The median follow-up time was 51 months (range, 3-74.5months). Over 90% of the patients had loco-regional advanced (III+IVa) diseases according to both editions. The 5-year OS, PFS and DMFS rates for the whole group were 82.6%, 84.0% and 88.7%, respectively. Based on the 8th edition, the OS and PFS curves of different T categories were better separated than 7th edition, except the T2 and T3 categories. The 8th edition had higher AIC and c-index values for OS and PFS than the 7th edition. While, for DMFS, the curves cannot be well separated according to both editions (all P values > 0.3). For N category, the survival curves of different groups were close to overlap for all the end points based on both editions. The AIC and c-index values were similar for the N categories of both editions. For clinical stage, the OS curves were better separated according to the 8th edition, while no significant differences could be reached for PFS or DMFS based on both editions.
Conclusion: The 8th edition of the UICC/AJCC staging system may not be able to well predict the treatment outcomes for NPC patients from non-endemic areas like Western China. More validation studies from non-endemic areas are needed.
The asset you are trying to access is locked. Please enter your access key to unlock.