Abstract
BackgroundIntensity-modulated radiation therapy (IMRT) has represented a technical milestone that has facilitated the clinical implementation. The purpose of this study was to evaluate the prognostic value of maximum primary tumor diameter (MPTD) in patients with nasopharyngeal carcinoma (NPC) treated using IMRT.MethodsFive-hundred and sixty-six patients with non-metastatic, histologically-confirmed NPC were retrospectively reviewed. MPTD was measured using magnetic resonance imaging (MRI). All patients were treated using IMRT; 87.5% (456/521) of patients with Stage T3-T4/N1-N3 disease also received cisplatin-based chemotherapy. Receiver operating characteristic (ROC) curves were used to identify the optimal MPTD cut-off point and examine the prognostic value of combining MPTD with the current T classification criteria.ResultsMedian follow-up for all patients was 36 months (range, 1–52 months). The 3-year overall survival (OS), failure-free survival (FFS), distant metastasis-free survival (DMFS), and local relapse-free survival (LRFS) rates for patients with a MPTD ≤41 vs. >41 mm were 96.1% vs. 85.4%, 93.7% vs. 74.7%, 96.1% vs. 79.7%, and 98.1% vs. 92.9%, respectively (all P < 0.05). In multivariate analysis, MPTD was an independent prognostic factor for OS, FFS, DMFS and LRFS in all patients (all P < 0.05). Among stage T3-T4 patients, the 3-year OS, FFS, DMFS, and LRFS rates for patients with a MPTD ≤41 vs. >41 mm were 96.9% vs. 84.5%, 95.4% vs. 73.5%, 96.1% vs. 79.2%, and 99.3% vs. 92.6%, respectively (all P < 0.05). In multivariate analysis, MPTD was also an independent prognostic factor for OS, FFS and DMFS in stage T3-T4 patients (all P < 0.05), and the difference in LRFS was almost statistically significant (P = 0.05). ROC curves verified that inclusion of MPTD improved the predictive value of the current T classification criteria (P < 0.001).ConclusionsMPTD was an independent prognostic factor in patients with NPC treated using IMRT, and significantly improved the prognostic value of the current T classification criteria for NPC.
Highlights
Intensity-modulated radiation therapy (IMRT) has represented a technical milestone that has facilitated the clinical implementation
As a result of the improved treatment outcomes provided in nasopharyngeal carcinoma (NPC) by IMRT, it is necessary to reassess the prognostic factors identified by analyses of patients treated with 2DRT and 3-DCRT [3,22,23]
This study demonstrates that maximum primary tumor diameter (MPTD) was an independent prognostic factor for overall survival (OS), failure-free survival (FFS), distant metastasis-free survival (DMFS) and local relapse-free survival (LRFS) in patients with NPC treated using IMRT
Summary
Intensity-modulated radiation therapy (IMRT) has represented a technical milestone that has facilitated the clinical implementation. The purpose of this study was to evaluate the prognostic value of maximum primary tumor diameter (MPTD) in patients with nasopharyngeal carcinoma (NPC) treated using IMRT. Compared to other head and neck carcinomas, nasopharyngeal carcinoma (NPC) has a number of unique characteristics. The introduction of intensity-modulated radiation therapy (IMRT) in the late 20th century represented a milestone in RT techniques. Lee et al initially reported that the 4-year local progression free survival rate for NPC after IMRT was 97% (in 67 patients, 70% of whom had stage III-IV disease) [6]. Other studies have confirmed that IMRT leads to excellent local control in NPC [7,8]
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.
