Prognostic significance of tumor volume in locally recurrent nasopharyngeal carcinoma treated with salvage intensity-modulated radiotherapy

WeiWei Xiao; Shuai Liu; YunMing Tian; Ying Guan; ShaoMin Huang; ChengGuang Lin; Chong Zhao; TaiXiang Lu; Fei Han

doi:10.1371/journal.pone.0125351

Prognostic significance of tumor volume in locally recurrent nasopharyngeal carcinoma treated with salvage intensity-modulated radiotherapy

PLoS One. 2015 Apr 30;10(4):e0125351. doi: 10.1371/journal.pone.0125351. eCollection 2015.

Authors

WeiWei Xiao¹, Shuai Liu¹, YunMing Tian², Ying Guan¹, ShaoMin Huang¹, ChengGuang Lin¹, Chong Zhao¹, TaiXiang Lu¹, Fei Han¹

Affiliations

¹ Department of Radiotherapy, SunYat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou, Guangdong, China.
² Department of Radiation Oncology, Hui Zhou Municipal Central Hospital, Huizhou, Guangdong, China.

Abstract

Introduction: To evaluate the prognostic value of gross tumor volume (TV) in patients with locally recurrent, nonmetastatic nasopharyngeal carcinoma.

Methods: Between 2001 and 2012, 291 consecutive patients with locally recurrent, nonmetastatic nasopharyngeal carcinoma underwent salvage IMRT were retrospectively reviewed. The correlations between TV and recurrent T classification were analyzed. Survival analyses were performed. Receiver operating characteristic (ROC) curves were calculated to identify cut-off point of TV. The Akaike information criterion and Harrell's concordance index (c-index) were utilized to test the prognostic value.

Results: The median TV significantly increased with advancing recurrent T classification (P<0.001). The 5-year overall survival rate was 33.2% for the entire cohort. On multivariate analysis, TV was an independent negative prognostic factor for distant metastasis-free survival (hazard ratio =1.013, P =0.003), overall survival (hazard ratio = 1.015, P<0.001) and toxicity-related death (hazard ratio = 1.014, P<0.001). The 5-year overall survival rates were 63.1% and 20.8% for patients with a TV < 22 cm3 and TV ≥22 cm3, respectively (P < 0.001). In patient with TV <22 cm3, locoregional failure is the leading cause of death. In patients with TV≥22 cm3, distant metastasis rate is higher and occurred within short term after local recurrence; meanwhile, radiation-induced injuries became more common and led to half of deaths in this group. The Akaike information criterion and c-index analyses indicated that the predictive ability of recurrent T classification improved when combined with TV.

Conclusions: Our data suggests TV is a significant prognostic factor for predicting the distant metastasis, overall survival and toxicity-related death of patients with locally recurrent, nonmetastatic nasopharyngeal carcinoma after salvage IMRT. TV should be considered when designing personalized salvage treatments for these patients. For patients with bulky local recurrent tumor, radiation may need to be de-emphasized in favor of systemic treatment or best supportive care.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adult
Aged
Carcinoma
Combined Modality Therapy
Female
Follow-Up Studies
Humans
Male
Middle Aged
Nasopharyngeal Carcinoma
Nasopharyngeal Neoplasms / mortality
Nasopharyngeal Neoplasms / pathology*
Nasopharyngeal Neoplasms / radiotherapy*
Neoplasm Recurrence, Local
Neoplasm Staging
Prognosis
Radiotherapy, Intensity-Modulated*
Retreatment
Salvage Therapy
Treatment Outcome
Tumor Burden
Young Adult

Grants and funding

This work was supported by Grant: Science and Technology Planning Project of Guangdong Province, China (No. 2012B061700089) and Young scientists fund of Sun Yat-sen University, China (No 12ykpy57). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.