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. 2020 Jan 29;11(7):1968-1975.
doi: 10.7150/jca.39588. eCollection 2020.

Analysis of Clinical Target Volume Delineation in Local-regional Failure of Nasopharyngeal Carcinoma after Intensity-modulated Radiotherapy

Xiaojing Yang  1 , Hanru Ren  2 , Weiwei Yu  1 , Xiulong Zhang  1 , Yi Sun  1 , Yuhui Shao  1 , Lihua Zhang  1 , Hongling Li  1 , Xinmiao Yang  1 , Jie Fu  1
Affiliations

Analysis of Clinical Target Volume Delineation in Local-regional Failure of Nasopharyngeal Carcinoma after Intensity-modulated Radiotherapy

Xiaojing Yang et al. J Cancer. .

Abstract

Objective: To analyze the pattern of local failure in patients with nasopharyngeal carcinoma (NPC) after intensity-modulated radiotherapy (IMRT) and find a more reasonable delineation of the clinical target volume (CTV).

Methods and materials: A total of 212 patients with non-metastatic NPC who underwent IMRT were analyzed. Radiation therapy was run at a total dose of 66-74 Gy (2.0-2.2 Gy fractions). The follow-up of local recurrence and the recurrence-related features were analyzed for the original treatment situation. The failures were delimited as "in-field failure" if Vrecur within the 95% isodose curve (V95%) was ≥95%; "marginal failure" if V95% was less than 95% and not less than 20%; or "out-field failure" if V95% was< 20%. Kaplan-Meier method was used to calculate the survival rates.

Results: The median follow-up was 43.4 months. The 5-year local relapse-free survival and overall survival rates were 85.6 and 77.8%, respectively. A total of 18 patients have relapsed. The in-field failure, marginal failure, and out-field failure accounted for 83.3%, 11.1%, and 5.6%, respectively. The site of recurrence was basically in the high dose area.

Conclusion: These findings suggested that IMRT provide a good local control for patients with NPC, and the in-field failure is the main mode. A wide range of CTV cannot prevent the local recurrence, narrowing the CTV to protect the adjacent organs should be taken into consideration.

Keywords: Clinical target volume; Delineation; Intensity-modulated radiotherapy; Nasopharyngeal carcinoma.

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Conflict of interest statement

Competing Interests: The authors have declared that no competing interest exists.

Figures

Figure 1
Figure 1
Kaplan-Meier analysis of overall survival (OS) (A) and local relapse-free survival (LRFS) (B) among patients, stratifed by age (C), gender (D), T stage (E), N stage (F), and AJCC stage (G).
See this image and copyright information in PMC

References

    1. Wang J, Shi M, Hsia Y. et al. Failure patterns and survival in patients with nasopharyngeal carcinoma treated with intensity modulated radiation in Northwest China: a pilot study. Radiat Oncol. 2012;7:2. - PMC - PubMed
    1. Ou X, Zhou X, Shi Q. et al. Treatment outcomes and late toxicities of 869 patients with nasopharyngeal carcinoma treated with definitive intensity modulated radiation therapy: new insight into the value of total dose of cisplatin and radiation boost. Oncotarget. 2015;6:38381–97. - PMC - PubMed
    1. Zhao W, Lei H, Zhu X. et al. Investigation of long-term survival outcomes and failure patterns of patients with nasopharyngeal carcinoma receiving intensity-modulated radiotherapy: a retrospective analysis. Oncotarget. 2016;7:86914–25. - PMC - PubMed
    1. Ng WT, Lee MC, Hung WM. et al. Clinical outcomes and patterns of failure after intensity-modulated radiotherapy for nasopharyngeal carcinoma. Int J Radiat Oncol Biol Phys. 2011;79:420–8. - PubMed
    1. Dawson LA, Anzai Y, Marsh L. et al. Patterns of local-regional recurrence following parotid-sparing conformal and segmental intensity-modulated radiotherapy for head and neck cancer. Int J Radiat Oncol Biol Phys. 2000;46:1117–26. - PubMed