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Comparative Study
. 2013 Jul 10;8(7):e67488.
doi: 10.1371/journal.pone.0067488. Print 2013.

Radiation-induced temporal lobe injury for nasopharyngeal carcinoma: a comparison of intensity-modulated radiotherapy and conventional two-dimensional radiotherapy

Guan-Qun Zhou  1 , Xiao-Li Yu, Mo Chen, Rui Guo, Ying Lei, Ying Sun, Yan-Ping Mao, Li-Zhi Liu, Li Li, Ai-Hua Lin, Jun Ma
Affiliations
Comparative Study

Radiation-induced temporal lobe injury for nasopharyngeal carcinoma: a comparison of intensity-modulated radiotherapy and conventional two-dimensional radiotherapy

Guan-Qun Zhou et al. PLoS One. .

Abstract

Background: To compare the radiation-induced temporal lobe injury (TLI) in patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT) or two-dimensional conventional radiotherapy (2D-CRT).

Patients and methods: 1276 cases of NPC treated with IMRT or 2D-CRT were retrospectively reviewed. A diagnosis of TLI was made on follow-up magnetic resonance imaging (MRI).

Results: The crude incidence of TLI was 7.5% and 10.8% (P = 0.048), and the actuarial 5-year incidence was 16% and 34.9% (P<0.001) for the IMRT and 2D-CRT groups, respectively. Multivariate analysis revealed both T stage (P<0.001) and radiation technique (P<0.001) as independent predictors. Patients with T1, T2 and T3 disease had a significantly higher risk when treated with 2D-CRT (P = 0.005, 0.016, <0.001, respectively). This trend was not evident for T4 patients (P = 0.680). The 2D-CRT group had a longer latency for the development of TLI (P<0.001). Those with T4 disease had a shorter median time to TLI (P = 0.006, 0.042, <0.001 when compared with T1, T2 and T3, respectively).

Conclusions: IMRT is superior to 2DRT for the management of T1-T3 NPC in terms of sparing the temporal lobe. The high incidence of TLI in T4 disease needs to be addressed.

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Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Figure 1
Figure 1. Representative MRI of patients with radiation-induced temporal lobe necrosis.
(a) the T2-weighted axial image shows a finger-like lesion of increased signal intensity (between the arrows); (b) the post-contrast T1-weighted axial image shows a lesion with necrosis and heterogeneous signal abnormalities (between the arrows); (c) the T2-weighted axial image shows an oval cyst with high T2 signal intensity (between the arrows).
Figure 2
Figure 2. Kaplan-Meier curve of temporal lobe necrosis probability.
Comparison of patients treated with intensity-modulated radiotherapy (IMRT) or conventional two-dimensional radiotherapy (2D-CRT).
Figure 3
Figure 3. Latency of occurrence of temporal lobe necrosis.
Patients treated with intensity-modulated radiotherapy (IMRT, left) vs. two-dimensional conventional radiotherapy (2D-CRT, right). Standard error bars are included and the thick horizontal line for each set of data points represents the median latent period.
Figure 4
Figure 4. Kaplan-Meier curves comparing the probability of temporal lobe necrosis in T1-T4 patients.
T1 disease (A), T2 disease (B), T3 disease (C), T4 disease (D) treated with intensity-modulated radiotherapy (IMRT) or two-dimensional conventional radiotherapy (2D-CRT).
See this image and copyright information in PMC

References

    1. Jemal A, Bray F (2011) Center MM, Ferlay J, Ward E, et al (2011) Global cancer statistics. CA Cancer J Clin 61: 69–90. - PubMed
    1. Lee AW, Ng SH, Ho JH, Tse VK, Poon YF, et al. (1988) Clinical diagnosis of late temporal lobe necrosis following radiation therapy for nasopharyngeal carcinoma. Cancer 61: 1535–42. - PubMed
    1. Lee AW, Sze WM, Fowler JF, Chappell R, Leung SF, et al. (1999) Caution on the use of altered fractionation for nasopharyngeal carcinoma. Radiother Oncol 52(3): 207–11. - PubMed
    1. Cheung MC, Chan AS, Law SC, Chan JH, Tse VK (2003) Impact of radionecrosis on cognitive dysfunction in patients after radiotherapy for nasopharyngeal carcinoma. Cancer 97(8): 2019–26. - PubMed
    1. Lee AW, Law SC, Ng SH, Chan DK, Poon YF, et al. (1992) Retrospective analysis of nasopharyngeal carcinoma treated during 1976–1985: Late complications following megavoltage irradiation. Br J Radiol 65: 918–928. - PubMed

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