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Featured researches published by Guan Qun Zhou.


International Journal of Radiation Oncology Biology Physics | 2012

Baseline serum lactate dehydrogenase levels for patients treated with intensity-modulated radiotherapy for nasopharyngeal carcinoma: a predictor of poor prognosis and subsequent liver metastasis.

Guan Qun Zhou; Ling Long Tang; Yan Ping Mao; Lei Chen; Wen Fei Li; Ying Sun; Li Zhi Liu; Li Li; Ai Hua Lin; Jun Ma

PURPOSE To evaluate the prognostic value of baseline serum lactate dehydrogenase (LDH) levels in patients with nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT). METHODS AND MATERIALS Cases of NPC (n = 465) that involved treatment with IMRT with or without chemotherapy were retrospectively analyzed. RESULTS The mean (±SD) and median baseline serum LDH levels for this cohort were 172.77 ± 2.28 and 164.00 IU/L, respectively. Levels of LDH were significantly elevated in patients with locoregionally advanced disease (p = 0.016). Elevated LDH levels were identified as a prognostic factor for rates of overall survival (OS), disease-free survival (DFS), and distant metastasis-free survival (DMFS), with p values <0.001 in the univariate analysis and p < 0.001, p = 0.004, and p = 0.003, respectively, in the multivariate analysis. Correspondingly, the prognostic impact of patient LDH levels was found to be statistically significant for rates of OS, DFS, and DMFS (p = 0.028, 0.024, and 0.020, respectively). For patients who experienced subsequent liver failure after treatment, markedly higher pretreatment serum LDH levels were detected compared with patients experiencing distant metastasis events at other sites (p = 0.032). CONCLUSIONS Elevated baseline LDH levels are associated with clinically advanced disease and are a poor prognosticator for OS, DFS, and DMFS for NPC patients. These results suggest that elevated serum levels of LDH should be considered when evaluating treatment options.


Radiotherapy and Oncology | 2014

Recommendation for a contouring method and atlas of organs at risk in nasopharyngeal carcinoma patients receiving intensity-modulated radiotherapy

Ying Sun; Xiao Li Yu; Wei Luo; Anne W.M. Lee; Joseph Wee; Nancy Y. Lee; Guan Qun Zhou; Ling Long Tang; Chang Juan Tao; Rui Guo; Yan Ping Mao; Rong Zhang; Ying Guo; Jun Ma

BACKGROUND AND PURPOSE To recommend contouring methods and atlas of organs at risk (OARs) for nasopharyngeal carcinoma (NPC) patients receiving intensity-modulated radiotherapy, in order to help reach a consensus on interpretations of OARs delineation. METHODS AND MATERIALS Two to four contouring methods for the middle ear, inner ear, temporal lobe, parotid gland and spinal cord were identified via systematic literature review; their volumes and dosimetric parameters were compared in 41 patients. Areas under the receiver operating characteristic curves for temporal lobe contouring were compared in 21 patients with unilateral temporal lobe necrosis (TLN). RESULTS Various contouring methods for the temporal lobe, middle ear, inner ear, parotid gland and spinal cord lead to different volumes and dosimetric parameters (P<0.05). For TLN, D1 of PRV was the most relevant dosimetric parameter and 64Gy was the critical point. We suggest contouring for the temporal lobe, middle ear, inner ear, parotid gland and spinal cord. A CT-MRI fusion atlas comprising 33 OARs was developed. CONCLUSIONS Different dosimetric parameters may hinder the dosimetric research. The present recommendation and atlas, may help reach a consensus on subjective interpretation of OARs delineation to reduce inter-institutional differences in NPC patients.


Chinese Journal of Cancer | 2012

Locoregional extension patterns of nasopharyngeal carcinoma and suggestions for clinical target volume delineation

Wen Fei Li; Ying Sun; Mo Chen; Ling Long Tang; Li Zhi Liu; Yan Ping Mao; Lei Chen; Guan Qun Zhou; Li Li; Jun Ma

Clinical target volume (CTV) delineation is crucial for tumor control and normal tissue protection. This study aimed to define the locoregional extension patterns of nasopharyngeal carcinoma (NPC) and to improve CTV delineation. Magnetic resonance imaging scans of 2366 newly diagnosed NPC patients were reviewed. According to incidence rates of tumor invasion, the anatomic sites surrounding the nasopharynx were classified into high-risk (>30%), medium-risk (5%–30%), and low-risk (<5%) groups. The lymph node (LN) level was determined according to the Radiation Therapy Oncology Group guidelines, which were further categorized into the upper neck (retropharyngeal region and level II), middle neck (levels III and Va), and lower neck (levels IV and Vb and the supraclavicular fossa). The high-risk anatomic sites were adjacent to the nasopharynx, whereas those at medium- or low-risk were separated from the nasopharynx. If the high-risk anatomic sites were involved, the rates of tumor invasion into the adjacent medium-risk sites increased; if not, the rates were significantly lower (P < 0.01). Among the 1920 (81.1%) patients with positive LN, the incidence rates of LN metastasis in the upper, middle, and lower neck were 99.6%, 30.2%, and 7.2%, respectively, and skip metastasis happened in only 1.2% of patients. In the 929 patients who had unilateral upper neck involvement, the rates of contralateral middle neck and lower neck involvement were 1.8% and 0.4%, respectively. Thus, local disease spreads stepwise from proximal sites to distal sites, and LN metastasis spreads from the upper neck to the lower neck. Individualized CTV delineation for NPC may be feasible.


PLOS ONE | 2013

Radiation-Induced Temporal Lobe Injury for Nasopharyngeal Carcinoma: A Comparison of Intensity-Modulated Radiotherapy and Conventional Two-Dimensional Radiotherapy

Guan Qun Zhou; Xiao Li Yu; Mo Chen; Rui Guo; Ying Lei; Ying Sun; Yan Ping Mao; Li Zhi Liu; Li Li; Ai Hua Lin; Jun Ma

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.


Journal of Cancer | 2015

Efficacy of the Additional Neoadjuvant Chemotherapy to Concurrent Chemoradiotherapy for Patients with Locoregionally Advanced Nasopharyngeal Carcinoma: a Bayesian Network Meta-analysis of Randomized Controlled Trials.

Yu Pei Chen; Rui Guo; Na Liu; Xu Liu; Yan Ping Mao; Ling Long Tang; Guan Qun Zhou; Ai Hua Lin; Ying Sun; Jun Ma

Background: Due to the lack of studies, it remains unclear whether the additional neoadjuvant chemotherapy (NACT) to concurrent chemoradiotherapy (CCRT) is superior to CCRT alone for locoregionally advanced nasopharyngeal carcinoma (NPC). The main objective of this Bayesian network meta-analysis was to determine the efficacy of NACT+CCRT as compared with CCRT alone. Methods: We comprehensively searched databases and extracted data from randomized controlled trials involving NPC patients who received NACT+CCRT, CCRT, NACT+radiotherapy (RT), or RT. Overall survival (OS) with hazard ratio (HR), and locoregional recurrence rate (LRR) and distant metastasis rate (DMR) with relative risks (RRs), were concerned. Results: Nine trials involving 1988 patients were analyzed. In the network meta-analysis, there was significant benefit of NACT+CCRT over CCRT for DMR (RR=0.54, 95% credible interval [CrI]=0.27-0.94). However, NACT+CCRT had a tendency to worsen locoregional control significantly as compared with CCRT (RR =1.71, 95%CrI =0.94-2.84), and no significant improvement in OS was found (HR =0.73, 95%CrI=0.40-1.23). Conclusions: NACT+CCRT is associated with reduced distant failure as compared with CCRT alone, and whether the additional NACT can improve survival for locoregionally advanced NPC should be further explored. Optimizing regimens and identifying patients at high risk of metastasis may enhance the efficacy of NACT+CCRT.


Radiotherapy and Oncology | 2015

Comorbidity predicts poor prognosis in nasopharyngeal carcinoma: Development and validation of a predictive score model

Rui Guo; Xiao Zhong Chen; Lei Chen; Feng Jiang; Ling Long Tang; Yan Ping Mao; Guan Qun Zhou; Wen Fei Li; Li Zhi Liu; Li Tian; Ai Hua Lin; Jun Ma

BACKGROUND AND PURPOSE The impact of comorbidity on prognosis in nasopharyngeal carcinoma (NPC) is poorly characterized. MATERIAL AND METHODS Using the Adult Comorbidity Evaluation-27 (ACE-27) system, we assessed the prognostic value of comorbidity and developed, validated and confirmed a predictive score model in a training set (n=658), internal validation set (n=658) and independent set (n=652) using area under the receiver operating curve analysis. RESULTS Comorbidity was present in 40.4% of 1968 patients (mild, 30.1%; moderate, 9.1%; severe, 1.2%). Compared to an ACE-27 score ⩽1, patients with an ACE-27 score >1 in the training set had shorter overall survival (OS) and disease-free survival (DFS) (both P<0.001), similar results were obtained in the other sets (P<0.05). In multivariate analysis, ACE-27 score was a significant independent prognostic factor for OS and DFS. The combined risk score model including ACE-27 had superior prognostic value to TNM stage alone in the internal validation set (0.70 vs. 0.66; P=0.02), independent set (0.73 vs. 0.67; P=0.002) and all patients (0.71 vs. 0.67; P<0.001). CONCLUSIONS Comorbidity significantly affects prognosis, especially in stages II and III, and should be incorporated into the TNM staging system for NPC. Assessment of comorbidity may improve outcome prediction and help tailor individualized treatment.


Radiotherapy and Oncology | 2015

Surrogate endpoints for overall survival in combined chemotherapy and radiotherapy trials in nasopharyngeal carcinoma: Meta-analysis of randomised controlled trials.

Yu Pei Chen; Ying Sun; Lei Chen; Yan Ping Mao; Ling Long Tang; Wen Fei Li; Xu Liu; Wen Na Zhang; Guan Qun Zhou; Rui Guo; Ai Hua Lin; Jun Ma

BACKGROUND AND PURPOSE We used a literature-based meta-analysis to assess whether failure-free survival (FFS) or progression-free survival (PFS) could be reliable surrogate endpoints for overall survival (OS) in trials of combined chemotherapy and radiotherapy for nasopharyngeal carcinoma (NPC). METHODS AND MATERIALS We identified randomised trials that evaluated combined chemoradiotherapy strategies, and reported FFS or PFS and OS in NPC. We analysed the treatment effects on FFS or PFS, and OS. We used the coefficient of determination (R(2)), and the surrogate threshold effect (STE) to assess the trial-level correlation. RESULTS Twenty-one trials (5212 patients), with sixteen treatment-control comparisons for FFS, and nine for PFS, were analysed. FFS was strongly correlated with OS (R(2)=0.88, STE=0.84), as was PFS (R(2)=0.90, STE=0.88). Moreover, FFS and PFS at 3 years were still strongly correlated with 5-year OS (R(2)=0.80, STE=0.83; R(2)=0.85, STE=0.84). CONCLUSIONS Both FFS and PFS could be valid surrogate endpoints for OS in trials of combined chemotherapy and radiotherapy for NPC; PFS may be a more acceptable surrogate endpoint compared with FFS.


Cancer Prevention Research | 2015

Low SFRP1 expression correlates with poor prognosis and promotes cell invasion by activating the Wnt/β-catenin signaling pathway in NPC

Xian Yue Ren; Guan Qun Zhou; Wei Jiang; Ying Sun; Ya Fei Xu; Ying Qin Li; Xin Ran Tang; Xin Wen; Qing Mei He; Xiao Jing Yang; Na Liu; Jun Ma

Distant metastasis remains the predominant mode of treatment failure in nasopharyngeal carcinoma (NPC). Unfortunately, the molecular events underlying NPC metastasis remain poorly understood. Secreted frizzled-related protein 1 (SFRP1) plays an important role in tumorigenesis and progression. However, little is known about the function and mechanism of SFRP1 in NPC. Immunohistochemistry was used to determine SFRP1 expression levels in patients with NPC. SFRP1 function was evaluated using MTT, colony formation, wound-healing, Transwell assays, and in vivo models. The methylation level of SFRP1 in NPC cells was examined using bisulfate pyrosequencing; the Wnt/β-catenin signaling pathway genes were studied using Western blotting. Compared with patients with high SFRP1 expression, patients with low SFRP1 expression had worse overall survival [HR, 2.32; 95% confidence interval (CI), 1.36–3.94; P = 0.002], disease-free survival (HR, 1.98; 95% CI, 1.23–3.18; P = 0.005), and distant metastasis-free survival (HR, 2.07; 95% CI, 1.19–3.59; P = 0.009). Multivariate Cox regression analysis indicated that SFRP1 was an independent prognostic factor. Furthermore, SFRP1 was significantly downregulated in NPC cell lines. SFRP1 overexpression suppressed NPC cell proliferation, migration, and invasion in vitro and lung colonization in vivo. SFRP1 expression was restored after treatment with a demethylation agent, and the SFRP1 promoter region was hypermethylated in NPC cells. β-Catenin, c-Myc, and cyclin D1 were downregulated after SFRP1 restoration, which suggested that SFRP1 suppressed growth and metastasis by inhibiting the Wnt/β-catenin signaling pathway in NPC. SFRP1 provides further insight into NPC progression and may provide novel therapeutic targets for NPC treatment. Cancer Prev Res; 8(10); 968–77. ©2015 AACR.


PLOS ONE | 2014

Comparison of Long-Term Survival and Toxicity of Cisplatin Delivered Weekly versus Every Three Weeks Concurrently with Intensity-Modulated Radiotherapy in Nasopharyngeal Carcinoma

Chang Juan Tao; Li Lin; Guan Qun Zhou; Ling Long Tang; Lei Chen; Yan Ping Mao; Mu Sheng Zeng; Tie Bang Kang; Wei Hua Jia; Jian Yong Shao; Hai Qiang Mai; Ai Hua Lin; Jun Ma; Ying Sun

Background We aimed to compare the long-term survival outcomes and acute toxicity of cisplatin administered weekly versus every three weeks concurrently with intensity-modulated radiotherapy (IMRT) in patients with nasopharyngeal carcinoma (NPC). Methods This was a retrospective review of 154 patients with histologically proven, non-disseminated NPC who were treated using IMRT between January 2003 and December 2007. Seventy-three patients (47.4%) received 5–7 weeks of 30–40 mg/m2 cisplatin weekly; 81 patients (52.6%) received two or three cycles of 80 mg/m2 cisplatin every three weeks. IMRT was delivered at 68 Gy/30 fractions to the nasopharyngeal gross target volume and 60–66 Gy to the involved neck area. Results The clinical characteristics and treatment factors of the two groups were well-balanced. The median follow-up was 74 months (range, 6–123 months), and the 5-year overall survival, disease-free survival, locoregional relapse-free survival, and distant metastasis–free survival rates were 85.2% vs. 78.9% (P = 0.318), 71.6% vs. 71.0% (P = 0.847), 93.5% vs. 92.6% (P = 0.904), and 80.9% vs. 80.1% (P = 0.925) for the group treated every three weeks and weekly, respectively. Subgroup analyses indicated no significant differences in the survival rates of the two groups among patients with early- or advanced-stage disease. The incidence of acute toxicities was similar between groups. Conclusion IMRT with concurrent cisplatin administered weekly or every three weeks leads to similar long-term survival outcomes and acute toxicity in NPC regardless of whether patients have early- or advanced-stage disease.


Cancer | 2014

Prognostic value of chronic hepatitis B virus infection in patients with nasopharyngeal carcinoma: analysis of 1301 patients from an endemic area in China.

Xu Liu; Xing Li; Ning Jiang; Ying Lei; Ling Long Tang; Lei Chen; Guan Qun Zhou; Ying Sun; Dan Yue; Rui Guo; Yan Ping Mao; Wen Fei Li; Li Zhi Liu; Li Tian; Ai Hua Lin; Jun Ma

The current study investigated the prevalence and prognostic value of chronic hepatitis B virus (HBV) infection in patients with nasopharyngeal carcinoma (NPC) from an area in southern China in which HBV and NPC are endemic.

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Ying Sun

Sun Yat-sen University

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Jun Ma

Sun Yat-sen University

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Ai Hua Lin

Sun Yat-sen University

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Lei Chen

Sun Yat-sen University

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Wen Fei Li

Sun Yat-sen University

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Rui Guo

Sun Yat-sen University

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Yu Pei Chen

Sun Yat-sen University

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Xu Liu

Sun Yat-sen University

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