[Effect of hypoxic radiosensitizer sodium glycididazole on long-term result of radiotherapy for nasopharyngeal carcinoma].
OBJECTIVE
To evaluate the long-term effect of sodium glycididazole (CMNa) as a hypoxic radiosensitizer on the radiotherapy for nasopharyngeal carcinoma.


METHODS
Between May 1999 and May 2002, 211 patients with pathologically confirmed nasopharyngeal carcinoma were randomized into group-A treated by radiotherapy plus CMNa or group-B by radiotherapy alone. The staging was determined according to 92' Fuzhou staging systerm. The type, procession and dosage of radiotherapy were identical in both groups. The early adverse effect grade was assessed based on the CTC2.0 criteria and the late adverse effects were evaluated according to the RTOG/EORTC criteria. The median follow-up time was 52 months. All the data was analyzed by the SPSS 13.0 software. Characteristics and adverse events of these patients were compared between the two groups using t-test and the Wilcoxin rank sum test. Time-to-event curves were estimated using the Kaplan-Meier method. The prognostic parameters were analyzed using univariate analysis and the Cox multivariate regression analysis.


RESULTS
The clinical data of the two groups were comparable. The 3-year survival was 88.4% in group-A, while 75.2% in group-B, with a statistically significant difference between two groups (P = 0.010). Univariate analysis showed that the 3-year survival was statistically correlated with N-staging ((N0-1, 86.9%, N2-3 73.8%, P < 0.001), T-staging (T1-2 85.6%, T3-4 79.3%, P = 0.014), TNM staging (P = 0.039), and whether using CMNa or not during rediotherapy (Group-A 88.4%, Group-B 75.2%, P = 0.010). The 5-year recurrence-free survival, 5-year metastasis-free survival and 5-year overall survival were 75.8%, 74.9% and 77.7% in Group-A, while 63.0%, 63.0% and 62.4% in Group-B with a statistically significant difference between two groups (0.013, 0.022 and 0.010, respectively). If stratified in the subgroups, the overall survival of stage III - IV patients was statistically different between group A and B (P = 0.009), however, not of stage I - II patients (P = 0.502). Cox multivariate regression analysis showed that the independent prognostic parameters for survival were N-stage (RR = 3.288) , T-stage (RR = 2.147) and use of CMNa during rediotherapy (RR = 0.407). However, there was no statistically significant difference between two groups in acute or late adverse effects on nervous system or heart, which suggested that use of CMNa during radiotherapy would not aggravate the toxicity caused by radiotherapy.


CONCLUSIONS
Sodium glycididazole is well tolerable effective as a hypoxic radiosensitizer, which can improve the efficacy of radiotherapy and the long-term result of nasopharyngeal carcinom a patients, especially for the stage III - IV patients.
Liu
Meng-Zhong
MZ
Department of Radiation Oncology, Cancer Center of Sun Yat-sen University, Guangzhou 510060, China. bedgoody@pub.guangzhou.gd.cn
He
Li-Ru
LR
Lu
Tai-Xiang
TX
Chen
Yuan-Yuan
YY
Hu
Yong-Hong
YH
Cui
Nian-Ji
NJ
Xu
Guo-Zheng
GZ
Gao
Li
L
Xiao
Guang-Li
GL
Zhang
Shan-Wen
SW
Cai
Yong
Y
Li
Dong-Ming
DM
Chen
Long-Hua
LH
Wang
Feng-Ying
FY
Sun
Qing
Q
Zhu
Li
L
Sheng
Ge
G
Gao
Hong-Jun
HJ
Bao
Yun-Hua
YH
D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D053208:Kaplan-Meier Estimate; D008297:Male; D008795:Metronidazole / Q000009:adverse effects / Q000031:analogs & derivatives* / Q000627:therapeutic use; D008875:Middle Aged; D015999:Multivariate Analysis; D009303:Nasopharyngeal Neoplasms / Q000473:pathology / Q000532:radiotherapy*; D009367:Neoplasm Staging / Q000706:statistics & numerical data; D011379:Prognosis; D016016:Proportional Hazards Models; D011838:Radiation-Sensitizing Agents / Q000009:adverse effects / Q000627:therapeutic use*; D013997:Time Factors; D016896:Treatment Outcome; D014839:Vomiting / Q000139:chemically induced
D011838:Radiation-Sensitizing Agents; C466518:sodium bimetrondazole glycinate; D008795:Metronidazole