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Background and Objective: Given the limited information regarding the impact of BMI on treatment outcomes for nasopharyngeal carcinoma, we sought to examine the relationship between body mass index (BMI) and cancer control after radiotherapy., Methods: We compared clinic outcome information across BMI groups from 1,489 patients treated with radiotherapy between 1990 and 2003. Multivariate analysis was used to determine if BMI significantly predicted adverse recurrence., Results: In comparison with normal group, there were statistical difference in age, T staging, N staging, and clinical staging (P<0.0001). In survival analysis, in comparison with under-weight group, we could found the hazard ratio was less than one, in the risk of death, cancer recurrence and local recurrence. Meanwhile, the hazard ratio gradually declined when the body weight increased. In univariate survival analysis, under-weight patient had a significant decrease in overall survival,(P<0.0001). When Cox regression model was applied to multivariate analysis, we could found age, T staging, N staging, and BMI grades could be a significant independent prognosis factors(P<0.05)., Conclusion: Under-weight patients had a significant decrease in overall survival rate, distant metastasis failure-free survival, and local relapse-free survival. Pretherapy BMI grades could be a significant independent prognosis factors.

Background & Objective: DNA double-strand break (DSB) is the main mechanism of tumor cell death after irradiation. Homologous recombination (HR) and DNA nonhomologous end-joining (NHEJ) are two important ways to repair DSB. The catalytic subunit of DNA-dependent protein kinase (DNA-PKcs), an essential protein of NHEJ, plays a major role during DSB. This study was to investigate the expression of DNA-PKcs in nasopharyngeal carcinoma (NPC), and analyze its correlation to the clinicopathologic features and prognosis of NPC., Methods: The expression of DNA-PKcs protein in 223 specimens of NPC tissues was detected by immunohistochemistry. The correlation of DNA-PKcs expression to clinicopathologic features and prognosis of NPC were analyzed., Results: The overexpression rate of DNA-PKcs in 223 NPC specimens was 36.8%. The expression of DNA-PKcs had no significant correlations to gender, age, pathological type and N staging of NPC (P>0.05), but had remarkable correlations to TNM, T and M staging (P<0.05). The 5-year overall survival rate was significantly lower in the patients with overexpression of DNA-PKcs than in those with low expression of DNA-PKcs (54.6% vs. 79.4%, P<0.05). T, N, M staging and the expression of DNA-PKcs were independent predictors for the overall survival of NPC (P<0.05)., Conclusions: DNA-PKcs is positively expressed in the majority of NPC tissues. The expression level of DNA-PKcs is an important factor affecting the prognosis of NPC, which could be used as a prognostic predictor for NPC.

Background & Objective: Cell cycle regulation is one of the most important determinants to ionizing radiosensitivity of cells. ATM gene is closely related with DNA damage repair and cell cycle checkpoints control. We previously reported that suppressing ATM expression with antisense ATM RNA could enhance radiosensitivity of nasopharyngeal carcinoma (NPC) cell line CNE1. This study was to explore the involved changes of cell cycle and the mechanisms of cell cycle arrest., Methods: ATM gene was constructed into retrovirus vector pDOR to form recombinant pDOR-atm. CNE1 cells were transfected with pDOR-atm (CNE1/pDOR-atm cells) or pDOR (CNE1/pDOR cells) and irradiated with X-ray. Cell cycle and cell apoptosis were detected by flow cytometry at different time points after irradiation., Results: S phase arrest was detected at 1, 4, and 8 h after irradiation in both groups, and G2 arrest at 24, and 48 h, while no comparable G1 arrest and apoptosis were revealed. The mean percentage of S phase cells was lower, and G2 phase cells was higher in CNE1/pDOR-atm group than in CNE1/pDOR group (P<0.05)., Conclusion: The mechanisms of cell cycle regulation in radiosensitized CNE1 cells by inhibiting ATM expression might be related with the decreased accumulation of S phase cells and increased accumulation of G2/M phase cells, while have no relationship with G1 arrest and apoptosis.

Background & Objective: Radiation-induced heart damage is one of the prognostic factors of the patients who had received radiation to the mediastinum. This study was to investigate the correlation of transforming growth factor-beta1 (TGF-beta1) mRNA expression to the radiation response of the heart in rats, in order to provide references for further study on irradiation-induced heart damage., Methods: Sixty Sprague-Dawley rats were divided into 2 groups: the 30 rats in irradiation group were irradiated with 20 Gy on the heart; the 30 rats in control group received no irradiation. At each time point of the 1st day, the 2nd, 4th, 8th 12th, and 24th week after irradiation, 5 rats in each group were killed. The serum levels of cardiac troponin and isoenzyme of creatine kinase (CK-MB) were detected. The expression of TGF-beta1 mRNA was detected by polymerase chain reaction (PCR). Heart damage was observed with Masson staining under microscope., Results: The serum level of cardiac troponin was elevated at 24 h after irradiation, and reached the peak at 2 weeks after irradiation, which was significantly higher than that in control group [(0.73+/-0.11) ng/mL vs. (0.11+/-0.04) ng/mL, P<0.05]. There was no significant difference in the serum level of CK-MB between two groups (P>0.05). The expression of TGF-beta1 mRNA was elevated at the 1st day after irradiation, and reached peaks at 2 and 12 weeks after irradiation, which were significantly higher than those in control group [(8.55+/-1.19)x10(-8) microg/mL vs. (1.27+/-0.11)x10(-8) microg/mL, (4.63+/-0.41)x10(-8) microg/mL vs. (1.35+/-0.15)x10(-8) microg/mL, P<0.05]. The proportion of collagen fibers was increased since 2 weeks after irradiation, which was significantly higher than that in control group [(2.87+/-0.37)% vs. (1.14+/-0.55)%, P<0.05]. The expression of TGF-beta1 mRNA was positively correlated to the proportion of collagen fibers in the rat hearts after irradiation (r=0.48, P<0.05)., Conclusions: TGF-beta1 is involved not only in the onset but also in the development of radiation fibrosis. Inhibiting the peak expression of TGF-beta1 mRNA may reduce the radiation-induced damage to the heart.

Background & Objective: Because of the heterogeneity of nasopharyngeal carcinoma (NPC), current TNM staging system could not indicate the prognosis of individual patients. Some available biological indexes would make up the deficiency of TNM staging system. This study was to investigate the prognostic significance of DNA ploidy in NPC., Methods: Between Jan. 1999 and Feb. 2000, the DNA ploidy in fresh NPC samples from 53 naive NPC patients with poorly differentiated squamous cell carcinoma was analyzed by flow cytometry (FCM). Of the 53 patients, 32 received radiotherapy alone, 21 received 1 course of chemotherapy (cisplatin plus 5-fluorouracil) at the end of the 4th week of radiotherapy., Results: Of the 53 patients, 32 (60.4%) had DNA diploid and 21 (39.6%) had DNA heteroploid. The differences in age, sex, clinical stage, N stage, and chemotherapy were not significant between diploid group and heteroploid group (P>0.05). The median follow-up was 73 months (range, 12-84 months). The 5-year overall survival rate was 65.61%. The 5-year overall, distant metastasis-free, and local progression-free survival rates were significantly higher in diploid group than in heteroploid group (80.92% vs. 42.86%, P=0.002; 84.26% vs. 44.53%, P=0.003; 92.59% vs. 72.65%, P=0.118). By Cox regression analysis, DNA ploidy and clinical stage were correlative factors for overall survival rate (P=0.020, P=0.017) and distant metastasis-free survival rate (P=0.007, P=0.011)., Conclusions: DNA ploidy and clinical stage are independent prognostic factors of NPC. The NPC patients with DNA heteroploid are more easily to emerge distant metastases than those with DNA diploid.

Background & Objective: Primary non-Hodgkin's lymphoma (NHL) of the nasal cavity has unique clinicopathologic features, and optimal treatment regimen remains unclear. This study was to summarize the clinical features, treatment outcomes, and prognostic factors of primary NHL of the nasal cavity at early stage., Methods: Records of 108 patients with primary NHL of the nasal cavity, consecutively treated at Cancer Center, Sun Yat-sen University from Jun. 1990 to Sep. 2004, were reviewed. All diagnoses were confirmed with pathology and immunochemistry. Seven cases were of B-cell phenotype. Survival prognostic factors were analyzed by Kaplan-Meier method and Cox regression model with SPSS12.0 software., Results: Median follow-up time for survived patients was 41 months. The overall complete remission (CR) rate after primary treatment was 67.6%, and CR rates were 80.2% for the patients received radiochemotherapy and 29.6% for the patients received chemotherapy alone. There were evidences indicating systemic relapse in 33 (30.6%) patients. With regard to the control of local, regional, and systemic failure, radiochemotherapy was better than chemotherapy alone. The 5-year overall survival rate was 50.0% for all patients. Both univariate analysis and multivariate analysis showed that pre-treatment history of more than 3 months, primary lesion limited in the nasal cavity, CR after primary treatment, and radiochemotherapy were favorable prognostic factors., Conclusions: Nasal cavity is frequently involved by peripheral T- and NK-cell lymphomas. Pre-treatment history of disease, extent of primary lesion involvement, and response to the primary treatment may be independent prognostic factors.

Background & Objective: Nasopharynx is a commonly involved site of non-Hodgkin's lymphoma (NHL), but the differences of clinical characteristics, prognosis, and treatment strategy between B-cell and NK/T-cell nasopharyngeal NHL have seldom been reported. This study was to investigate the clinical manifestations and treatment outcomes of primary B-cell and NK/T-cell nasopharyngeal NHL at early stage, and evaluate the prognostic differences, so as to provide evidences for treatment optimization., Methods: Clinical data of 80 patients with previously untreated nasopharyngeal NHL at early stage, admitted from May 1987 to Nov. 2003, were reviewed. Of the 80 cases, 48 were B-cell original (B group), 32 were NK/T-cell original (T group). Of the 80 patients, 42 received chemoradiotherapy, 31 received chemotherapy alone, and 7 received radiotherapy alone. Most chemotherapy-treated patients received CHOP regimen (cyclophosphamide, vincristine, adriamycin, and prednisone) for 1-10 cycles (median 5 cycles). Radiotherapy was given with high energy photon beams combined with high energy electron beams in conventional fractionation, with the total dose of 30-70 Gy (median 52 Gy). Treatment patterns of the 2 groups were similar, but B group received more chemotherapy cycles than T group did., Results: The 5-year overall survival rate and 5-year progression-free survival rate were significantly higher in B group than in T group (69.5% vs. 35.5%, P=0.003; 53.3% vs. 28.9%, P=0.032). Cox multivariate regression analysis suggested that B-cell phenotype, no B symptoms, and local control were independent favorable predictors of overall survival, while B-cell phenotype and good treatment response were independent favorable predictors of progression-free survival. Univariate stratified analysis with Kaplan-Meier method showed that, for B group, the cumulative 5-year overall survival rate was 68.1% in the 19 patients received chemotherapy alone, 61.7% in the 25 patients received chemoradiotherapy, and 100% in the 4 patients received radiotherapy alone (P=0.311); for T group, the cumulative 5-year overall survival rate was 0% in the 12 patients received chemotherapy alone, 44.1% in the 17 patients received chemoradiotherapy, and 33.3% in the 3 patients received radiotherapy alone (only 1 patient survived for 60 months)(P=0.020)., Conclusions: Among the patients with primary nasopharyngeal NHL at early stage, those with B-cell phenotype may have better prognosis as compared with those with NK/T-cell phenotype. The patients with NK/T-cell phenotype often suffered from B symptoms, with poor response to chemotherapy. Radiotherapy or chemoradiotherapy should be more emphasized in this group of patients.

Background & Objective: It is reported that ATM gene is closely correlated to cellular radiosensitivity in several malignant tumors. Suppression of ATM protein expression leads to cellular radiosensitization. This study was to determine whether this effect also exists in nasopharyngeal carcinoma (NPC) cell line CNE1 by inhibiting the expression of ATM protein through antisense RNA of ATM/PI3K region, which is the most important functional fragment of ATM gene., Methods: The recombinant pDOR-atm expressing antisense RNA of ATM/PI3K segment was constructed with retroviral vector pDOR. CNE1 cells were stably transfected with pDOR-atm by cationic liposome and named CNE1/pDOR-atm. Semi-quantitive RT-PCR was used to detect the level of ATM mRNA. Flow cytometry (FCM) was employed to analyze the percentage of positive cells and mean fluorescence density of protein expressing ATM. Cellular radiosensitivity was evaluated by colony survival assay (CSA) and linear-quadratic model in both CNE1/ pDOR-atm and control cells., Results: The level of ATM mRNA index (RI) was 0.23+/-0.02 in CNE1/pDOR-atm group, and 0.51+/-0.03 in control group (P<0.05). The percentage of positive cells and mean fluorescence density of proteins expressing ATM were 70.8% and 1.81+/-0.12 in CNE1/pDOR-atm group, while 99.3% and 4.51+/-0.18 in control group(P<0.01). The expression of ATM mRNA and protein was inhibited by antisense RNA. The alpha value (one function from linear-quadratic model) of CNE1/pDOR-atm group was 0.40 Gy(-1), while it was 0.36 Gy(-1) in control group. The radiosensitizing ratio of surviving fraction at 2 Gy (SF(2)) was 3.0, indicating that antisense RNA group was more radiosensitive to X-ray than the controls., Conclusion: NPC cell line CNE1 could be radiosensitized by the down-regulation of ATM/PI3K expression.

Background & Objective: The incidence of primary central nervous system lymphoma (PCNSL) is increasing, and its prognosis is poor. This study was to investigate the clinical features of PCNSL, and evaluate the efficacy of high-dose methotrexate (MTX)-based chemotherapy for immunocompetent Chinese patients with PCNSL., Methods: Clinical data of 32 patients (median age, 50 years) with pathologically confirmed PCNSL were analyzed retrospectively. Before Nov. 2001, CHOP with or without whole brain radiotherapy (WBRT) was employed; after then, high-dose MTX-based chemotherapy with or without WBRT was employed., Results: Of the 32 PCNSL patients, 25 (78.1%) were more than 45 years old; 24 (75.0%) suffered intracranial hypertension; 25 (78.1%) had single intracranial mass; no positive case of cerebrospinal fluid (CSF) cellular examination was found; 28 (87.5%) were B-cell lymphoma, among which 19 (59.4%) were diffuse large B-cell lymphoma. Median follow-up of the patients was 13.5 months (1-84 months). Kaplan-Meier test showed that the median overall survival time was 26 months, and the 2-year survival rate was 45.7%. The complete response rate of the 18 patients who received high-dose MTX-based chemotherapy plus WBRT was 61.1%, the median survival time was more than 26 months, and the 2-year survival rate was 65.1%. The efficacy of high-dose MTX-based chemotherapy plus WBRT was better than that of CHOP plus WBRT. Log-rank test showed that the survival time of the patients with performance status (PS) of 0-1 or normal serum lactate dehydrogenase (LDH) was longer than those with PS of 2-3 or elevated LDH., Conclusions: PCNSL often occurs in middle-aged and aged patients, with intracranial hypertension as the main clinical manifestation. B-cell lymphoma is the predominant subtype. High-dose MTX-based chemotherapy plus WBRT is efficient and feasible for PCNSL.

Background & Objective: On the basis of our previous research, this study was to validate the rationality of AJCC/UICC staging system (1997) of nasopharyngeal carcinoma (NPC), and to provide some suggestions., Methods: Survival data of 915 NPC patients, received radical radiotherapy alone in Cancer Center of Sun Yat-sen University from Jan. 1997 to Dec. 1998, were analyzed with Life table, Cox regression, Kaplan-Meier, and log-rank methods., Results: Cox regression analysis showed that the 5-year survival rate of the 915 patients was significantly correlated to their age and tumor stage classified according to AJCC/UICC (1997) staging system; while that of the 803 patients no more than 60 years old was only significantly correlated to tumor stage. Life table analysis validated that the tumor stage classified according to AJCC/UICC staging system can roughly predict the prognosis, but the differences between stage I and IIa, or IVa and IVb were not significant. Kaplan-Meier analysis showed no significant differences of survival rate between stage T1 and T2a, or T3 and T4 when adjusted by N classification, and between stage N2 and N3a, or N3a and N3b when adjusted by T classification. Therefore, we adjusted stage T2a to T1, stage N1 with inferior cervical nodes metastasis to N2, combined stage N3a and N3b to N3, adjusted stage IIa to I, stage IIb to II, and stage IVb to IVa. After the modifications, the differences among stages I-IVa, T1-T4 (adjusted by N classification) and N0-N3 (adjusted by T classification) were significant., Conclusion: Taking the impact of age on the prognosis and the interaction between T stage and N stage into consideration, the above modifications should be included when renewing the AJCC/UICC staging system (1997).

Background & Objective: Radiotherapy is one of the most important adjuvant treatments for patients with malignant glioma, but radiosensitivities of gliomas are widely various. This study was to induce human glioma cell line MGR2 to become a stable radioresistant cell subline, and investigate the mechanisms of radioresistance., Methods: Human glioma cell line MGR2, with survival fraction of 2 Gy (SF(2)) of 0.18+/-0.05, was irradiated by intermittent high dose X-ray (2 Gy for 3 times, 5 Gy for 2 times). After each irradiation, the cells were cultured for 5 to 8 weeks and received irradiation again. The whole process of irradiation and culture lasted for 11 months. The cells derived from MGR2 were obtained and named MGR2R (MGR2 radiation induction). Double times of MGR2 and MGR2R cells were determined by MTT assay. Dose-survival curves, radiobiological parameters and SF2 were determined by colony-forming assay and line-quadratic model. The variation of their cell cycles was investigated by flow cytometry and cell cycle synchronization of serum-starvation., Results: The double time of MGR2 cells was 3.6 days, while that of MGR2R cells was 4.0 days. The growth rate of MGR2R cells was slower than that of MGR2 cells. Using colony-forming assay and line-quadratic model, the parameters of MGR2 and MGR2R were obtained. The alpha values of MGR2 and MGR2R were 0.447 and 0.089 (t=4.524, P=0.011), the beta values were 0.177 and 0.141 (t=1.562, P=0.193), and the SF(2) were 0.208 and 0.478 (t=-6.062, P=0.040), respectively. The radioresistance of MGR2R cells was stronger than that of MGR2 cells. The distribution of cell cycle in MGR2 cells after synchronization were 54.8% in G(1) phase, 30.9% in S phase, and 14.3% in G(2) phase; 24 h after loss of synchronization, the distribution of cell cycle were 35.9% in G(1) phase, 51.2% in S phase, and 12.8% in G(2) phase. The distribution of cell cycle in MGR2R cells after synchronization were 55.7% in G(1) phase, 27.8% in S phase, and 16.6% in G(2) phase; 24 h after loss of synchronization, the distribution of cell cycle were 56.4% in G1 phase, 26.7% in S phase, and 16.9% in G(2) phase. MGR2R cells appeared G(2) phase arrest before synchronization, and G1 phase arrest after loss of synchronization., Conclusions: After intermittent high dose X-ray irradiation, radiosensitive cell line MGR2 has been induced to be relatively radioresistant (MGR2R). MGR2R cells grow slower and have G(1) phase and G(2) phase arrest which might relate to its radioresistance.

Background & Objective: Nasal-type NK/T-cell non-Hodgkin's lymphoma (NHL) is a unique subtype with the manifestation of local necrosis, infection and fever. The efficacy of chemotherapy alone is unsatisfactory; while radiochemotherapy plays some roles in the management of NK/T-cell lymphoma (NK/TCL). This study was to summarize the clinical characteristics, treatment outcome and prognosis of NK/TCL patients., Methods: Records of 93 patients with NK/TCL from Jan. 1997 to Jun. 2004 were analyzed retrospectively. All the patients were classified according to WHO classification system., Results: Of the 93 patients, 75 (80.6%) were in stage I-II, and 18 (19.4%) were in stage III-IV. The most common symptoms were nasal obstruction, rhinorrhea, and epistaxis. The disease course was 1-24 months with a median of 6.5 months. Of the 93 patients, 15 (16.1%) presented perforation of hard palate and/or nasal septum, 35 (37.6%) presented B symptoms; 35 (37.6%) were treated with chemotherapy alone, 2 (2.2%) were treated with radiotherapy alone, 54 (58.0%) were treated with radiochemotherapy, and 2 (2.2%) received no treatment. The first-line chemotherapy regimens were mainly CHOP and EPOCH. The overall response rate (RR) was 84.4% (76/90) with complete remission (CR) rate of 64.4% (58/90). The response rate of chemotherapy alone group was 67.6% (23/34) with CR rate of 41.2% (14/34). The response rate of combined modality group was 94.4% (51/54) with CR rate of 83.3% (45/54). The 2 patients who received no treatment died within 6 months. The major toxicity of chemotherapy was myelosuppression. The prevalence of grade III-IV neutropenia, thrombocytopenia, and anemia were 37.7%, 13.7%, and 10.7%. The major toxicities of radiotherapy were grade I-II mucosa lesion and myelosuppression. Other toxicities were mild. The mortality was 66.7% (62/93). The 1-, 3-, and 5-year overall survival (OS) rates were 63.4%, 43.1%, and 17.6%, respectively. Multivariate analysis showed that perforation of hard palate and/or nasal septum, B symptoms and therapeutic modality were independent prognostic factors of NK/TCL (P=0.035, P<0.001, and P=0.004)., Conclusions: NK/TCL has low chemotherapy sensitivity. Although combined chemoradiotherapy yield better outcome, the long-term survival was still poor. Investigation of optional treatment is needed.

Background & Objective: Since three-dimensional culture simulates in vivo microenvironment better than planar culture, the biological character of cells in three-dimensional culture model are more similar with that of living tissues. This study was to establish three-dimensional culture models that represent different stages of nasopharyngeal caicinogenesis, and provide information to elucidate the related molecular events., Methods: Non-tumor nasopharyngeal biopsy specimens were used to culture for normal nasopharyngeal epithelial cells. Early and late passages of normal nasopharyngeal epithelial cell line NPNE2 from nasopharyngeal biopsy specimens, immortalized nasopharyngeal epithelial cell line NP69SV40T, nasopharyngeal carcinoma (NPC) cell line SUNE-1 and its high metastatic subclone 5-8F were cultured in Matrigel to establish three-dimensional models., Results: The cells grew out of non-tumor nasopharyngeal biopsy specimens displayed the morphologic characteristics as epithelia, and could proliferate in vitro for 8-10 passages before senescence. Immunocytochemical staining of cytokeratin revealed that the cells were of epithelial origin. All of the cells, except late passages of NPNE2 cells, could proliferate in the three-dimensional culture system. NPNE2 and NP69SV40T cells mainly developed reticular structures in morphology, and formed few clones with clear and smooth edges as well as tight intercellular junctions. SUNE-1 and 5-8F cells formed clones with irregular morphology, unclear edge, and loose intercellular junctions. In addition, the clones formed by 5-8F cells also developed a lot of pseudopodia, but developed no reticular structure. Late passages of NPNE2 cells formed no clone and reticular structure in the three-dimensional culture., Conclusions: Normal nasopharyngeal epithelial cells can be successfully cultured in vitro from naspharyngeal biopsy specimens. The three-dimensional culture models, established with normal nasopharyngeal epithelial cells, immortalized nasopharyngeal epithelial cells, and NPC cells, may represent the different stages of nasopharyngeal carcinogenesis.

Background & Objective: With the elevation of survival rate of nasopharyngeal carcinoma (NPC) patients after treatment, their quality of life (QOL) is more and more emphasized. This study was designed to evaluate the QOL of disease-freely survival NPC patients after treatment, and to investigate the factors correlated with their QOL., Methods: From Jul. to Aug. 2003, disease-freely survival NPC patients who had been treated from 1999 to 2000 in Cancer Center of Sun Yat-sen University were enrolled. The Chinese SF-36 questionnaire and a checklist consists of 14 items about self-rating symptoms were self-reported by all participants at clinic. Sociodemographic and clinical data of the patients were also collected, and their relationships with SF-36 data and symptoms were analyzed., Results: A total of 192 patients were enrolled in the study. The median survival time was 3.6 years (ranged 2.4-4.6 years). Xerostomia was the first common symptom, followed by hypoacusis, hypomnesia, dysphagia, and trismus. Univariate analysis showed that gender, age, educational level, monthly income, economic status, religion, and the number of complications had influences on QOL; the patients in earlier T and N stages, irradiated by linear accelerator, with lower total dose and weekly dosage to the nasopharynx and neck, and those who had anterior nasal field radiation reported better QOL. Multiple stepwise regression analysis showed that the number of complications, monthly income, age, and T stage were independent factors affecting total QOL., Conclusions: Improving radiotherapy might enhance physical functions of NPC patients. The prevention and control of chronic diseases, the development of economy, and the increase of income may promote NPC patients' QOL.

Background & Objective: Along with the development of treatments, different tumor staging systems are coexisted and have been modified. This study was to validate the rationality of the Fuzhou staging system (1992) of nasopharyngeal carcinoma (NPC), and to provide some suggestions., Methods: A total of 915 NPC patients received radical radiotherapy alone in Cancer Center of Sun Yat-sen University from Jan. 1997 to Dec. 1998. The 1-, 3-, and 5-year follow-up rates were 98.7%, 95.2%, and 91.7%, respectively. The survival data were analyzed with Life table, Cox regression, Kaplan-Meier, and log-rank methods., Results: The 1-, 3-, and 5-year overall survival rates of the 915 patients were 87.69%, 72.73%, and 64.44%; the 1-, 3-, and 5-year disease-freely survival rates were 86.87%, 69.72%, and 58.33%, respectively. Cox regression analysis showed that the 5-year survival statuses of the 915 patients were significantly correlated with their age and the tumor stage classified by the Fuzhou staging system (1992); the 5-year survival statuses of the 803 patients no more than 60 years old were only significantly correlated with tumor stage, and had no correlation with their age. Life table analysis validated that the tumor stage classified by Fuzhou staging system (1992) can roughly predict the prognosis, but the difference between the 5-year survival rates of stage I and II patients was not significant. Kaplan-Meier analysis showed no significant difference between survival statuses of stage T1 and T2 patients when adjusted by N classification. Therefore, we adjusted stage T2 without parapharyngeal space invasion to stage T1, stage T3 with carotid vagina invasion to stage T2, stage T4 with paranasal sinus involvement to stage T3, stage T3 with cranial nerve injury to stage T4, and stage N1 with bilateral lymph nodes involvement to stage N2. After the modifications, the differences among stage I to IVa, stage T1 to T4 (adjusted by N stage), or stage N0 to N3 (adjusted by T stage) were significant., Conclusion: Taking the impact of age on the prognosis and the interaction between T stage and N stage into consideration, the above modifications of should be included when renewing the Fuzhou staging system (1992).

Background & Objective: In order to improve quality assurance (QA) and quality control (QC) of radiotherapy, individualized vacuum bag is used in the localization of radiation treatment, gradually becoming one of the important steps for the QA and QC in the many departments of radiation oncology. It is controversial whether localization with vacuum bags under the simulator influences the precision of direct measurement for tumor depth in the isocentric posterior oblique field in the patients with thoracic and abdominal tumors. This study was designed to explore the influence of vacuum bag on the direct measurement, Methods: Twenty-nine patients with thoracic and abdominal carcinoma who had to need isocentric irradiation in the supine position were immobilized using vacuum bag. The irradiation depths of 45 posterior oblique fields were determined by CT-simulator and conventional simulator, respectively; then the absolute value for the difference of both depths was regarded as error value., Results: There were 37 fields (82.2%) with error value of smaller than 5 mm; 8 fields (17.8%), more than 5 mm. In the latter, 5 field were belonged to be repositioned in the phase II of radiotherapy because of light leaking air into the vacuum bag in the phase I of radiotherapy., Conclusion: Vacuum bag has a slight influence on direct measurement for depths of isocentric posterior oblique field.

Background & Objective: The superoxide anion and the hydroxyl radical (OH.) play an important role in the radiotherapy of tumors. The superoxide dismutase (SOD) and the metallothionien (MT) are the main enzymes to clear the superoxide anion and OH. Up to now, there are few reports on the relationship between the nasopharyngeal carcinoma (NPC) and SOD or MT. This study was conducted to observe the dynamic changes of the activity of total superoxide dismutase (T-SOD) in the serum and the expression of MT in the tissue from the NPC patients treated with radiotherapy., Methods: From December 2000 to January 2002, 46 patients with NPC were selected randomly to test the activity of T-SOD in serum using xanthine oxidase method and the expression of MT in tissue using immunohistochemistry before, during, and after radiotherapy. And 26 persons without cancer were enrolled as normal control., Results: Thirty-two patients were performed 3 times of examinations of T-SOD activity. The activity of T-SOD before radiotherapy (83.9+/-19.6 U(N)/ml) was lower than normal control (96.8+/-23.6 U(N)/ml) (P< 0.05). The activities of T-SOD in the serum samples before, during, and after the radiotherapy were 77.6+/-19.1, 87.1+/-18.6, and 96.3+/-31.6 in the NPC patients at stage I(P >0.05); 80.1+/-15.0, 78.0+/-35.4, and 110.6+/-72.0 in the NPC patients at stage IV(P >0.05); 79.8+/-18.2, 87.2+/-31.7, and 94.8+/-36.3 in the patients with complete response to radiotherapy (P >0.05); 98.5+/-18.6, 62.9+/-35.3, and 79.2+/-27.3 in the patients with part response to radiotherapy (P >0.05). Among the 32 patients, 27 patients were performed 3 times of tests of MT expression. The expression rate of MT in NPC tissues was 39.8+/-37.8% before radiotherapy, and markedly higher than the normal control 12.1+/-22.4% (P< 0.05). The expression rates of MT before, during, and after radiotherapy were 33.0+/-42.2%, 21.3+/-36.1%, and 5.0+/-10.0% in the tissues from the patients at stage I(P< 0.05); 62.2+/-40.5%, 9.2+/-12.8%, and 9.2+/-15.0% in the patients at stage IV( P< 0.05); 42.5+/-38.6%, 19.8+/-27.5%, and 10.0+/-13.9% in the patients with complete response to radiotherapy (P< 0.05); 32.3+/-37.2%, 1.43+/-2.43%, and 5.4+/-9.1% in the patients with part response to radiotherapy (P< 0.05)., Conclusion: The test of T-SOD in serum may be helpful for the diagnosis of initial NPC. But the dynamic change of the activity of total T-SOD in radiotherapy was not obvious. The expression rates of MT in NPC tissues increased markedly before radiotherapy, and decreased obviously after radiotherapy.

Background & Objective: It has been reported that ataxia- telangiectasia mutant(ATM) protein is closely correlated with cellular radiosensitivity in several malignant tumors. This study was designed to determine the expression of ATM protein in two nasopharyngeal carcinoma (NPC) cell lines with different radiosensitivity., Methods: Two NPC cell lines, CNE1 and CNE2, with different radiosensitivity were established. The localization and quantity of ATM protein were analyzed by fluorescence immunohistochemical method and laser scanning confocal microscope(LSCM)., Results: ATM protein was located in both karyon and cytoplasm, especially strongly expressed in karyon. The intense fluorescence of ATM protein was stronger in karyon of CNE1 than that in CNE2., Conclusion: The expression levels of ATM protein differ in CNE1 and CNE2. The variance may be a potential factor, which links with their different radiosensitivity.

Background & Objective: Brain metastasis is often found in the patients with lung cancer. Radiotherapy is regular and effective method, and it aims at palliating symptoms and prolonging survival time. However, now there are different viewpoints on protocols of radiotherapy and prognostic factors. A retrospective analysis was used to evaluate the results of treatment for 63 cases with brain metastasis from lung cancer and explore the prognostic factors., Materials and Methods: Sixty-three patients of brain metastasis from lung cancer from Jan. 1994 to Dec. 2000 were studied retrospectively. All of them have received radiotherapy (RT) and 42 cases received combined chemotherapy. The median dose of radiotherapy was 40Gy(24-62.4 Gy). Mean survival times from two factors were compared by t-test and the cumulative survival rate was analyzed by Kaplan-Meier estimates, and the influencing factors were screened by Cox proportional hazard model., Results: The mean survival times were 9.5 months in the radiochemotherapy group and 6.3 months in radiotherapy alone group, 9.3 months in good response group and 5.0 months in the poor response group (P = 0.043), 10.8 months in the > or = 50 Gy group and 6.7 months in the < 50 Gy group(P = 0.028), and 10 months in > or = 1.8 Gy fraction group and 4.8 months in the < 1.8 Gy fraction group (P = 0.015). Survival analysis results suggested that the patients with combined chemotherapy and good response have better prognosis., Conclusions: Combined chemotherapy and efficacy at the end of treatment are independent prognosis factors of brain metastasis from lung cancer.