• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.22
• /
• pp.9899-9903
• /
• 2014

Nasopharyngeal carcinoma (NPC) is an uncommon disease in most countries but occurs with much greater frequency in southern China. This study aimed to examine the secular trends of NPC in urban Guangzhou over the time period of 2000-2011 using data from the Guangzhou Cancer Registry. Age-adjusted annual incidence rates of NPC were calculated by the direct method using the WHO World Standard Population (1960) as the reference. The average annual percentage change (AAPC) was used as an estimate of the trend. A total of 7,532 new cases of NPC and 3,449 related deaths were registered. In both genders, the peak incidence occurred in the 50- to 59-year age group, and this age distribution pattern remained similar throughout. The AAPC in NPC incidence rates was -3.26% (95% CI: -5.4%--1.1) for males and -5.74% (95% CI: -8.9%--2.5) for females, resulting in a total decrease of 39.3% (from 22.14 to 13.44 per 100,000 population) for males and 48.6% (from 10.1 to 5.18 per 100,000 population) for females over this 12-year period. The AAPCs in NPC mortality rates were -4.62% (95%CI: -3.5%--5.7) for males and -6.75% (95% CI: -5.2%--8.3) for females, resulting in a total decrease of -46.1% (from 12.1 to 6.54 per 100,000 population) for males and 51.7% (from 4.14 to 2.00 per 100,000 population) for females. The age-adjusted incidence and mortality rates of NPC declined during 2000-2011 in urban Guangzhou but remained high. Future efforts to improve prevention, early detection and treatment strategies are needed.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.6
• /
• pp.2495-2502
• /
• 2012

Nasopharyngeal carcinoma (NPC) is a disease with distinct ethnic and geographic distribution. The incidence of NPC in Chinese residing in Asia has declined over the last few decades, but NPC mortality trends in the entire Chinese population over time have not been systematically evaluated. In this study, we examined NPC mortality at the national level in China between 1973-2005. Mortality rates were derived from the databases of national retrospective surveys on cancer mortality conducted in the periods of 1973-1975, 1990-1992, and 2004-2005, respectively. NPC was classified according to the International classification of diseases. Age-adjusted mortality rates were calculated by direct standardization according to the world standard population. Trends in rates were evaluated by age, gender, geographic areas, and socioeconomic status. From 1973 to 2005, there was a general trend of decrease in NPC mortality in China, with higher rates in the south on a downward trend in the north. The age-standardized NPC mortality rates were 2.60 per 100,000 in 1973-1975, 1.94 per 100,000 in 1990-1992, and 1.30 per 100,000 in 2004-2005, respectively. The trend was similar in both men and women, in both urban and rural areas, but the declining rates in females were more remarkable than in males. The mortality rates were higher for the age groups above 50 years than those less than 50 years of age, both showing downward trend over 30-year period. In summary, the overall NPC mortality has consistently decreased in China over the past three decades, particularly in women and in old adults.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.6
• /
• pp.2577-2581
• /
• 2012

Objective: To conduct a meta-analysis to investigate the value of EBV DNA in diagnosis of nasopharyngeal cancer (NPC) in Asian populations, and provide important evidence for screening. Methods: Prospective or respective case-control or cohort studies regarding the detection role of EBV DNA for NPC were included in our study. We conducted a comprehensive literature search in PubMed, EMBASE, and the Chinese Biomedical Database (CBM database between January 1980 and March 2012. Results: A total of 18 studies with 1492 NPC cases and 2641 health controls were included. Almost of the included studies were conducted in China, and only one other conducted in Thailand. The overall results demonstrated that the pooled sensitivity, specificity, positive likelihood (+LR) and negative likelihood (-LR) were 0.73 (0.71-0.75), 0.89 (0.88-0.90), 8.84 (5.65-13.84) and 0.19(0.11-0.32), respectively. The overall EBV DNA detection showed the largest area of 0.932 under the summary receiver operator curve (SROC). The accuracy of detection by plasma for NPC (0.86) was higher than in serum (0.81), with largest areas under the SROC of 0.97 and 0.91, respectively. Conclusion: Our results demonstrated the EBV DNA detection in plasma or serum has high sensitivity and specificity in diagnosis of NPC, especially in Chinese populations with a high risk of cancer.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.22
• /
• pp.9797-9800
• /
• 2014

Background: Nasopharyngeal carcinoma (NPC) is a common cancer in Southern China and Southeast Asia. Alu elements are among the most prevalent repetitive sequences and constitute 11% of the human genome. Although Alu methylation has been evaluated in many types of cancer, few studies have examined the levels of this modification in serum from NPC patients. Objective: To compare the Alu methylation levels and patterns between serum from NPC patients and normal controls. Materials and Methods: Sera from 50 NPC patients and 140 controls were examined. Quantitative combined bisulfite restriction analysis-Alu (qCOBRA-Alu) was applied to measure Alu methylation levels and characterize Alu methylation patterns. Amplified products were classified into four patterns according to the methylation status of 2 CpG sites: hypermethylated (methylation at both loci), partially methylated (methylation of either of the two loci), and hypomethylated (unmethylated at both loci). Results: A comparison of normal control sera with NPC sera revealed that the latter presented a significantly lower methylation level (p=0.0002) and a significantly higher percentage of hypomethylated loci (p=0.0002). The sensitivity of the higher percentage of Alu hypomethyted loci for distinguishing NPC patients from normal controls was 96%. Conclusions: Alu elements in the circulating DNA of NPC patients are hypomethylated. Moreover, Alu hypomethylated loci may represent a potential biomarker for NPC screening.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.12
• /
• pp.7395-7400
• /
• 2013

Objective: The long-term efficacy of microwave hyperthermia combined with chemoradiotherapy in treating nasopharyngeal carcinoma (NPC) with metastatic foci in cervical lymph nodes was evaluated. Methods: A total of 154 cases of N2 or N3 stage NPC were randomized into two groups: hyperthermia group (76 cases) and control group (78 cases). Both received cisplatin chemotherapy and radiotherapy. In addition, the hyperthermia group further received microwave hyperthermia to the metastatic cervical nodes with different patterns (before or after radiotherapy), heating temperatures (T90< $43^{\circ}C$ and $T90{\geq}43^{\circ}C$) and hyperthermia episodes (< 4 times, 4-10 times and > 10 times). Results: The 3-month and 5-year complete response (CR) rates of cervical lymph nodes in the hyperthermia group were significantly higher than those in the control group. The 5-year disease-free survival (DFS) rate and the 3-year / 5-year overall survival rate in the hyperthermia group were also significantly higher. There was no significant difference in 5-year metastatic rates. In the hyperthermia group, the 3-month and 5-year CR rates of T90< $43^{\circ}C$ treatment were significantly lower than with $T90{\geq}43^{\circ}C$ treatment. The CR rate was highest when the hyperthermia was performed 4-10 times. There were no significant differences in 3-month and 5-year CR rates between hyperthermia before or after radiotherapy treatment. Conclusion: Microwave hyperthermia combined with chemoradiotherapy can increase local control, DFS and 3, 5-year overall survival rates of patients with N2 ~ N3 stage NPC. The heating temperature should be over $43^{\circ}C$ with hyperthermia repeated 4-10 times.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.12
• /
• pp.7577-7581
• /
• 2013

The interleukin-18 promoter -607C>A gene polymorphism may be related to nasopharyngeal carcinoma (NPC) risk but the results of individual studies remain conflicting. A meta-analysis including 1,886 subjects from five individual studies was therefore performed to provide a more accurate estimation. Pooled odds ratios (ORs) and their corresponding 95% confidence intervals (95% CIs) were evaluated by fixed- or random-effects models. A significant relationship between interleukin-18 promoter -607C>A gene polymorphism and NPC was found in a dominant genetic model (OR: 1.351, 95% CI: 1.089-1.676, P=0.006, $P_{heterogeneity}$=0.904), a homozygote model (OR: 1.338, 95% CI: 1.023-1.751, P=0.034, $P_{heterogeneity}$=0.863), and a heterozygote model (OR: 1.357, 95% CI: 1.080-1.704, P=0.009, $P_{heterogeneity}$=0.824). No significant association was detected in either an allelic genetic model (OR: 1.077, 95% CI: 0.960-1.207, 0.207, $P_{heterogeneity}$=0.844) or a recessive genetic model (OR: 1.093, 95% CI: 0.878-1.361, P=0.425, $P_{heterogeneity}$=0.707). In conclusion, a significant association was found between interleukin-18 promoter -607C>A gene polymorphism and NPC risk. Individuals with the C allele of interleukin-18 promoter -607C>A gene polymorphism have a higher risk of NPC development.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.12
• /
• pp.6133-6137
• /
• 2012

Purpose: To study the effect of bolus versus no bolus in the coverage of the nodal tumour volume with intensity-modulated radiotherapy (IMRT) for the treatment of nasopharyngeal carcinoma (NPC). Methods and Materials: This retrospective study used data from 5 consecutive patients with NPC who were treated with bolus for large neck nodes using IMRT from November 2011-January 2012 in our institute. All these patients were treated radically with IMRT according to our institution's protocol. Re-planning with IMRT without bolus for these patients with exactly the same target volumes were done for comparison. Comparison of the plans was done by comparing the V70 of PTV70-N, V66.5 of PTV70-N, V65.1 of PTV70-N and the surface dose of the PTV70-N. Results: The mean size of the largest diameter of the enlarged lymph nodes for the 5 patients was 3.9 cm. The mean distance of the GTV-N to the skin surface was 0.6 cm. The mean V70 of PTV70-N for the 5 patients showed an absolute advantage of 10.8% (92.4% vs. 81.6%) for the plan with bolus while the V66.5 of PTV70-N had an advantage of 8.1% (97.0% vs. 88.9%). The mean V65.1 also had an advantage of 7.1% (97.6% vs. 90.5%). The mean surface dose for the PTV70-N was also much higher at 61.1 Gy for the plans with bolus compared to only 23.5 Gy for the plans without bolus. Conclusion: Neck node bolus technique should be strongly considered in the treatment of NPC with enlarged lymph nodes treated with IMRT. It yields a superior dosimetry compared t o non-bolus plans with acceptable skin toxicity.

• Asian Pacific Journal of Cancer Prevention
• /
• v.13 no.12
• /
• pp.6005-6010
• /
• 2012

Background: Nasopharyngeal carcinoma (NPC) is endemic in Southern Chinese and Southeast Asian populations. Geographical and ethnic clustering of the cancer is due to genetic, environmental, and lifestyle risk factors. This case-control study aimed to identify or confirm both genetic and non-genetic risk factors for NPC in one of the endemic countries, Malaysia. Materials and Methods: A panel of 768 single-nucleotide polymorphisms (SNPs) previously associated with various cancers and known non-genetic risk factors for NPC were selected and analyzed for their associations with NPC in a case-control study. Results: Statistical analysis identified 40 SNPs associated with NPC risk in our population, including 5 documented previously by genome-wide association studies (GWAS) and other case-control studies; the associations of the remaining 35 SNPs with NPC were novel. In addition, consistent with previous studies, exposure to occupational hazards, overconsumption of salt-cured foods, red meat, as well as low intake of fruits and vegetables were also associated with NPC risk. Conclusions: In short, this study confirmed and/or identified genetic, environmental and dietary risk factors associated with NPC susceptibility in a Southeast Asian population.

• Asian Pacific Journal of Cancer Prevention
• /
• v.15 no.4
• /
• pp.1851-1857
• /
• 2014

Objective: The main purpose of this work was to investigate the effect of berberine hydrochloride (BH) on the proliferation, apoptosis, migration, and invasion of CNE-1 nasopharyngeal carcinoma cells. Our results shed light on the functional components of traditional Chinese herbs for potential use in modern medicine. Methods: The CNE-1 cell line was treated with different concentrations of BH and effects on cell viability and proliferation were evaluated using the Cell Counting Kit-8 (CCK-8) assay. Anti-migratory and anti-invasive actions of BH were investigated using wound healing assays and the Millicell Hanging cell culture insert system, respectively. Expression of the epithelial-mesenchymal transition (EMT)-related gene twist (Twist) was analyzed by real-time PCR and Western blotting. Apoptosis was estimated with an annexin-V fluorescein (FITC) apoptosis detection kit, as well as with reference to levels of activated caspase-3 of CNE-1 cells before and after treatment with BH utilizing fluorescence spectroscopy. Results: BH was capable of reducing proliferation and viability of CNE-1 cells in a dose- and time-dependent manner, also demonstrating anti-migratory and anti-invasive capacities which correlated with reduction in expression of Twist. Finally, BH was able to induce significant amounts of apoptosis in CNE-1 cells, as demonstrated by an increase in the activity of caspase-3 and in annexin-V staining following treatment. Conclusion: BH extracted from rhizoma coptidis demonstrated an ability to block proliferation, induce apoptosis, and impair the migration and invasion of the CNE-1 cell line Considering these properties, our results suggest that BH could be an important compound for consideration in the treatment of nasopharyngeal carcinoma.

• Asian Pacific Journal of Cancer Prevention
• /
• v.14 no.11
• /
• pp.6513-6518
• /
• 2013

Background: To evaluate the treatment outcome and major late complications of all patients with recurrent nasopharyngeal carcinoma (NPC) treated with intracavitary brachytherapy (ICBT) in Hospital Kuala Lumpur. Materials and Methods: This retrospective study was conducted at the Department of Radiotherapy and Oncology, Hospital Kuala Lumpur, Malaysia. All patients with histologically confirmed recurrent NPC in the absence of distant metastasis treated in the period 1997-2010 were included in this study. These patients were treated with ICBT alone or in combination with external beam radiotherapy (EBRT). Treatment outcomes measured were local recurrence free survival (LRFS), disease free survival (DFS) and overall survival (OS). Results: Thirty three patients were eligible for this study. The median age at recurrence was 56 years with a median time to initial local recurrence of 27 months. Majority of patients were staged as rT1-2 (94%) or rN0 (82%). The proportion of patients categorised as stage III-IV at first local recurrence was only 9%. Twenty one patients received a combination of ICBT and external beam radiotherapy while 12 patients were treated with ICBT alone. Median interval of recurrence post re-irradiation was 32 months (range: 4-110 months). The median LRFS, DFS and OS were 30 months, 29 months and 36 months respectively. The 5 year LRFS, DFS and OS were 44.7%, 38.8% and 28.1% respectively. The N stage at recurrence was found to be a significant prognostic factor for LRFS and DFS after multivariate analysis. Major late complications occurred in 34.9% of our patients. Conclusions: Our study shows ICBT was associated with a reasonable long term outcome in salvaging recurrent NPC although major complications remained a significant problem. The N stage at recurrence was a significant prognostic factor for both LRFS and DFS.