ObjectiveCompare the two-degrade collimator (MLC) angle selection's impact on plan quality and operational efficiency for volumetric intensity-modulated radiotherapy (VMAT) in the treatment planning system, and to explore the scheme for treatment plan optimization. MethodsTwenty patients with nasopharyngeal carcinoma underwent the treatment between March and December 2013 were randomly selected and planned for SIBVMAT treatment with different parameters set in the range of 0-60°with 15°interval for collimator angles. Planned dose distribution to the target volumes, organs at risk, and monitor units were compared. ResultsAs the MLC angle increased, target conformal index and homogeneity index had a trend to became deteriorated. The optimal plans were 0°and 15°, while 45°and 60°plans gave poor protection for the organ at risk compare to other angle plans and the monitor units were significantly increased. ConclusionChange the MLC angle had visible impact on treatment plans,there was a trend to deteriorate with the MLC angle increased, but small changes in MLC angle range can theoretically reduce the influence from leakage radiation on the human body.
ObjectiveTo systematically review the correlation between the expression of P53 and nasopharyngeal carcinoma. MethodsDatabases including The Cochrane Library (Issue 1, 2016), PubMed, EMbase, CBM, CNKI, VIP, and WanFang Data were searched from the inception to January 1st 2016 to collect case-control studies about the correlation between the expression of P53 and nasopharyngeal carcinoma, as well as its clinically pathologic features. Two reviewers independently screened literature, extracted data and assessed the risk of bias of included studies. Then meta-analysis was performed using RevMan 5.2 software. Results Twelve studies were finally included in this meta-analysis. There were 630 cases of nasopharyngeal carcinoma and 253 controls. The results of meta-analysis showed that, the expression of P53 protein were significantly different between the nasopharyngeal carcinoma group and the control group (OR=21.34, 95%CI 13.59 to 33.50, P < 0.000 01), between the nasopharyngeal carcinoma with lymphatic node metastasis group and without lymphatic node metastasis group (OR=3.69, 95%CI 1.67 to 8.17, P=0.001), between the clinical stage Ⅰ to Ⅱ group and the clinical stage Ⅲ to Ⅳ group (OR=0.19, 95%CI 0.08 to 0.49, P=0.000 6). However, there were no significant differences in expression of P53 between the male nasopharyngeal carcinoma group and the female nasopharyngeal carcinoma group (OR=0.92, 95%CI 0.49 to 1.74, P=0.80), and between the < 50 nasopharyngeal carcinoma group and the≥50 nasopharyngeal carcinoma group (OR=1.70, 95%CI 0.70 to 4.11, P=0.24). ConclusionsCurrent evidence shows that, the expression of P53 protein is associated with the occurrence, development of nasopharyngeal carcinoma and may be positively correlated to degree of tumor malignance. It may be an indicator poor prognosis.
Nasopharyngeal carcinoma (NPC) is rather common in Southeast Asia and Southern China. The standard treatment for NPC is intensity-modulated radiotherapy (IMRT). A large number of the NPC survivors benefit from the IMRT, while some suffer from the late toxicities which can be life-threatening or significantly erode the patients’ quality of life and functional status, especially in the locally advanced NPC. Nowadays the late radiotherapy-related toxicities have been the most important concern for the radiotherapists and patients, who look forward to the better long-term tumor local control and overall survival. Therefore, we carried out a review about the late radiotherapy-related toxicities of the vital organs at risk after IMRT for NPC patients.
Epstein-Barr (EB) virus infection is associated with various tumors of lymphoid and epithelial origin. EB virus exists in most humans as a latent infection. EB virus latent infection-related genes play a key role in the EB virus latent infection, and also play an important role in promoting the occurrence and development of related tumors. This article will briefly introduce the characteristics of EB virus latent infection, the protein coding genes and non-coding genes related to EB virus latent infection (including EB virus nuclear antigen genes, EB virus latent membrane protein genes, EB virus encoded small RNA genes and EB virus microRNA genes), and the main functional mechanism of these EB virus latent infection-related genes in EB virus latent infection and subsequent tumorigenesis. The purpose is to providea theoretical basis for a comprehensive understanding of the EB virus latent infection and the mechanism of tumors caused by EB virus.
ObjectiveTo explore the application value of plasma Epstein-Barr virus (EBV) DNA test in the clinical diagnosis of patients with nasopharyngeal carcinoma in non-high-incidence areas of Southwest China and its significance for monitoring patients after treatment. MethodsA total of 235 patients diagnosed with non-keratinized nasopharyngeal carcinoma between January 2014 and December 2015 were retrospectively collected. The plasma EBV-DNA test rate of the nasopharyngeal carcinoma patients before treatment, the positive rates of the plasma EBV-DNA test before treatment and within 6 months of treatment, and the relationship between the positivity of plasma EBV-DNA within 6 months of treatment and the prognosis of nasopharyngeal carcinoma were analyzed. ResultsThe plasma EBV-DNA test rate of the nasopharyngeal carcinoma patients before treatment was 69.79% (164/235), with a positive rate of 90.85% (149/164). A total of 131 patients were tested for EBV-DNA within 6 months of treatment, whose positive rate was 89.31% (117/131) before treatment and 21.37% (28/131) within 6 months of treatment, respectively, with a statistically significant difference (P<0.001). Comparing the prognosis of EBV-DNA positive patients and negative patients within 6 months of treatment, the difference in 3-year recurrence rate between the two groups was not statistically significant (10.71% vs. 3.88%, P=0.341); however, the 3-year metastasis rate (21.43% vs. 4.85%, P=0.016) and the 3-year disease progression rate (32.14% vs. 6.80%, P=0.001) of the EBV-DNA positive patients were higher than those of the EBV-DNA negative patients, and the log-rank test slao showed that the 3-year progression-free survival rate (67.86% vs. 93.20%, P<0.001) and the 3-year metastasis-free survival rate (78.57% vs. 95.15%, P=0.004) of the EBV-DNA positive patients were lower than those of the EBV-DNA negative patients. There was no statistically significant between-group difference in the 3-year progression-free survival curve when grouped by age, gender, or TNM staging (P>0.05).ConclusionsFor patients with non-keratinized nasopharyngeal carcinoma in non-high-incidence areas of Southwest China, EBV-DNA detection is important for the screening and diagnosis of nasopharyngeal carcinoma, and the positivity of EBV-DNA test within half a year of treatment is an important factor affecting the prognosis and progression of patients. Plasma EBV-DNA levels should be monitored regularly before and after treatment.
ObjectiveTo systematically review the health economic evaluation of nasopharyngeal carcinoma (NPC). MethodsThe PubMed, Web of Science, EMbase, CNKI, WanFang Data and CBM databases were electronically searched to collect the health economic evaluations on NPC from inception to December 18, 2022. Two reviewers independently screened literature, extracted data and assessed the risk of bias of the included studies. A descriptive analysis was performed. ResultsA total of 20 studies were included, which contained 14 about different drug combinations, 6 about chemotherapy and the comparison among intensity modulated radiotherapy, conventional radiotherapy and surgery. The results showed that for patients with recurrent, metastatic, or advanced NPC, compared with docetaxel plus cisplatin, fluorouracil plus cisplatin or docetaxel and cisplatin plus fluorouracil, gemcitabine plus cisplatin (GP) was the most economical, and compared with GP or camrelizumab plus GP, toripalimab plus GP (TGP) was more economical. For early-stage NPC, intensity modulated radiotherapy was not economical compared with conventional radiotherapy and surgery. ConclusionCurrent evidence shows that GP and TGP are economical and can be popularized clinically.