A study on the value of narrow-band imaging (NBI) for the general investigation of a high-risk population of nasopharyngeal carcinoma (NPC).

BACKGROUND: This study aims to explore the feasibility of narrow-band imaging (NBI) applied for the diagnostic screening of a high-risk population of nasopharyngeal carcinoma (NPC) and increase the accuracy rate of nasopharyngeal biopsy and the diagnosis rate of early-stage patients. METHODS: The positive high-risk population of NPC to EB virus antibody was followed up. At the same time, serological screening and pharyngorhinoscopy were carried out. The specific methods were as follows: (1) all subjects received nasopharyngeal examinations through both the HD endoscopic white light mode (WL) and NBI mode, (2) nasopharyngeal biopsy was conducted on positive subjects with microscopic examination, and, finally, (3) a comparative analysis was conducted between the biopsy pathology results and microscopy results. In addition, the following comparative indicators were recorded under different modes: sensitivity, specificity, accuracy, positive likelihood ratio, and negative likelihood ratio. Then, the area under the ROC curve and the kappa coefficient were calculated. RESULTS: A total of 115 subjects were detected to be positive by microscopic examination under the WL mode. Among these subjects, 19 subjects were diagnosed with NPC. In addition, 24 subjects were detected to be positive by microscopic examination under the NBI mode. Among these subjects, 23 subjects were diagnosed with NPC. Under the WL mode, the specific values of the comparative indicators were as follows: sensitivity, 82.61%; specificity, 0%; and area under the ROC curve, 0.413. Furthermore, the WL mode in the diagnosis on the high-risk population of NPC exhibited poor consistency with the biopsy pathology results (kappa coefficient = - 0.069). Under the NBI mode, the specific values of the comparative indicators were as follows: sensitivity, 100%; specificity, 98.96%; and area under the ROC curve, 0.995. Furthermore, the NBI mode in the diagnosis on the high-risk population of NPC exhibited relatively satisfactory consistency with the biopsy pathology results (kappa coefficient = 0.973). Therefore, the NBI mode is significantly superior to the WL mode. CONCLUSION: NBI endoscopic examinations should be conducted on a routine basis for high-risk populations of NPC. This can decrease the frequency of biopsies and enhance diagnostic effects.

Influence of endoscopic sinus surgery on the quality of life of patients with early nasopharyngeal carcinoma and the analysis of prognosis-related factors.

The aim of this study is investigate the influence of endoscopic sinus surgery on the quality of life and prognosis of patients with early nasopharyngeal carcinoma. Patients initially diagnosed with early nasopharyngeal carcinoma and received surgical treatment were matched with nasopharyngeal carcinoma patients who received chemoradiotherapy at a ratio of 1:1, according to the following seven factors: gender, age, T staging, N staging, clinical staging, radiotherapy options, and chemotherapy options. Patients in the surgery group received endoscopic sinus surgery plus chemoradiotherapy, while subjects in the control group received chemoradiotherapy. The quality of life of patients before and after treatment was evaluated based on the FACT-H&N (Functional Assessment of Cancer Therapy-Head and Neck) and QLQ-H&N35 (Head and Neck Cancer Specific Module) questionnaires. In addition, overall survival and disease-free survival were compared between these two groups. The results showed overall survival was superior in the surgery group compared with the control group ( p = 0.007). However, the difference in disease-free survival between these two groups was not statistically significant ( p = 0.128). Furthermore, subgroup analysis revealed that for N0 patients, the effect of surgery combined with chemoradiotherapy on overall survival was superior to that of chemoradiotherapy ( p = 0.048); while for N1 patients, the difference in overall survival between these two groups was not statistically significant ( p = 0.065). For early nasopharyngeal carcinoma patients without lymph node metastasis, overall survival and disease-free survival in T1 patients were superior to those in T2 patients (χ2 = 4.403, p = 0.036; χ2 = 4.542, p = 0.033). At the end of treatment, the pain score was found to be significantly lower in the surgery group than in the chemoradiotherapy group ( p = 0.027). At 3 months and 1 year after treatment, dry mouth scores were significantly lower in the surgery group than in the chemoradiotherapy group ( p = 0.002, p = 0.026). These results demonstrated that the curative effect of surgery combined with chemoradiotherapy in the treatment of nasopharyngeal carcinoma was satisfactory and was particularly suitable for N0 patients.

Distribution and clinical significance of circulating tumor cells in nasopharyngeal carcinoma.

OBJECTIVE: Nasopharyngeal carcinoma is one of the leading malignancies with obscure etiology. Circulating tumor cells have been showed to intimately correlate with characteristics in different kinds of cancer. But links between circulating tumor cells and nasopharyngeal carcinoma were still lacking. Therefore, we explored circulating tumor cells' distribution in nasopharyngeal carcinoma and their possible associations with nasopharyngeal carcinoma. METHODS: Firstly, we found that the positive ratio of circulating tumor cells is extremely high in four stages of nasopharyngeal carcinoma. Meanwhile, positive ratios of mesenchymal circulating tumor cells were higher in early stages of nasopharyngeal carcinoma. Apart from epithelial circulating tumor cells, total, hybrid and mesenchymal circulating tumor cells were correlated with nasopharyngeal carcinoma clinical stage. RESULTS: Our results showed that hybrid and mesenchymal circulating tumor cells were associated with nasopharyngeal carcinoma metastasis (both distant and lymph node) and smoking. Meanwhile, hybrid circulating tumor cells expressed the highest Epstein-Barr virus proteins and deoxyribonucleic acid in three types of circulating tumor cells. Moreover, we found that Epstein-Barr virus proteins viral-caspid antigen-immunoglobulin A (VCA/IgA) and early antigen-immunoglobulin A (EA/IgA), but not Epstein-Barr virus-deoxyribonucleic acid, had a closed association with nasopharyngeal carcinoma metastasis. However, Epstein-Barr virus hallmarks failed to associate with other nasopharyngeal carcinoma characteristics. Furthermore, we confirmed that matrix metalloproteinase 9 existed in circulating tumor cells and expressed most in mesenchymal circulating tumor cells. In addition, matrix metalloproteinase 9-expressed extent in hybrid circulating tumor cells is somewhat different from epithelial and mesenchymal circulating tumor cells in matrix metalloproteinase 9-positive circulating tumor cells. Nevertheless, matrix metalloproteinase 9 had no relationship with other nasopharyngeal carcinoma characteristics. Finally, our results showed that circulating tumor cells were decreased in patients after therapies. CONCLUSION: Taken together, circulating tumor cells were tightly correlated with nasopharyngeal carcinoma characteristics. In addition, Epstein-Barr virus was associated with nasopharyngeal carcinoma metastasis. Of note, decreased circulating tumor cells indicated a favorable curative effect in nasopharyngeal carcinoma patients.

The Safety and Immunological Effects of rAd5-EBV-LMP2 Vaccine in Nasopharyngeal Carcinoma Patients: A Phase I Clinical Trial and Two-Year Follow-Up.

Epstein-Barr virus (EBV)-encoded latent membrane protein 2 (LMP2) promotes nasopharyngeal carcinoma (NPC) progression. Previously, we reported that the dendritic cells (DCs) transfected with EBV-LMP2 recombinant serotype 5 adenoviruses (rAd5) induced anti-tumor effect by eliciting cytotoxic T lymphocytes (CTLs)-mediated immune response in vitro and the adenoviral vaccine of EBV-LMP2 (rAd5-EBV-LMP2) stimulated antigen-specific cellular immunity in mice. However, the safety and immunological effect of rAd5-EBV-LMP2 vaccine in human still remained unknown. Here we conducted a single-center, non-randomized, open-label, single-arm phase I clinical trial to clarify this unsolved issue. A total of 24 patients with regional advanced NPC were sequentially enrolled into three dose level groups (2×10(9), 2×10(10), 2×10(11) vp). The rAd5-EBV-LMP2 vaccines were intramuscularly injected for four times within 28 d (D0, D7, D14, D28). Blood samples were harvested immediately before every vaccination, one week and one month after the last vaccination (D0, D7, D14, D28, D35, D58). All the vaccine inoculation-related toxicities presented as grade I/II adverse events. The most frequent systemic adverse reactions were fatigue (33.0%, 8/24), myalgia (29.2%, 7/24) and cough (29.2%, 7/24), while the most common regional adverse reaction was tenderness in the inoculation site (54.2%, 13/24). In addition, proportion of CD(3+)CD(4+) cells in peripheral blood was significantly increased in the high dose group (2×10(11) vp). The rAd5-EBV-LMP2 vaccine was generally well-tolerated and the high dose (2×10(11) vp) is recommended to be adopted in phase II studies. The long-term outcome of rAd5-EBV-LMP2 vaccine inoculation is required to be determined in following placebo-controlled trials.

Regulatory Mechanism of lncRNA CTBP1-AS2 in Nasopharyngeal Carcinoma Cell Proliferation and Apoptosis via the miR-140-5p/BMP2 Axis.

OBJECTIVE: Nasopharyngeal carcinoma (NPC) is a squamous cell carcinoma. LncRNA CTBP1-AS2 (CTBP1-AS2) has effects on tumor cell growth. This study explored the mechanism of CTBP1-AS2 on NPC cells. METHODS: CTBP1-AS2 expressions in immortalized nasopharyngeal epithelial (NP69) and 6 human NPC cells were detected by RT-qPCR and SUNE-1/CNE-1 cells with relative high/low expressions were selected. Cell proliferation and apoptosis were detected by CCK-8, colony formation assays, and flow cytometry. The binding sites between CTBP1-AS2 and miR-140-5p and miR-140-5p and BMP2 were predicted, and the binding relationships were verified by dual-luciferase assay. BMP2 level was detected by Western blot. miR-140-5p was silenced, or BMP2 was overexpressed in SUNE-1 cells with si-CTBP1-AS2 to study the effects of miR-140-5p and BMP2 on CTBP1-AS2 silencing-inhibited malignant behaviors. RESULTS: CTBP1-AS2 was upregulated in NPC cells. CTBP1-AS2 silencing suppressed NPC cell proliferation and promoted apoptosis. CTBP1-AS2 silencing in SUNE-1 cells raised miR-140-5p expression and repressed BMP2 level. CTBP1-AS2 overexpression in CNE-1 cells suppressed miR- 140-5p expression and elevated BMP2 levels. DISCUSSION: In mechanism, miR-140-5p overexpression decreased BMP2 levels, reduced NPC cell proliferation, and promoted apoptosis. miR-140-5p knockdown or BMP2 overexpression enhanced NPC cell proliferation and inhibited apoptosis, thus restoring NPC cell malignant behaviors inhibited by silencing CTBP1-AS2. CONCLUSION: CTBP1-AS2 decreased miR-140-5p-induced BMP2 inhibition via functioning as a ceRNA of miR-140-5p and promoted BMP2 expression, thereby promoting NPC cell proliferation and suppressing apoptosis.

A Four-Gene Signature Model Improves the Prediction of Distant Metastasis in Patients with Nasopharyngeal Carcinoma: A Retrospective, Three-Center Observational Study.

Background: Similar to that in other malignant tumors, distant metastasis is one of the most important causes of poor prognosis in nasopharyngeal carcinoma (NPC). However, the genetic hallmarks and networks that regulate the distant metastasis of NPC are not fully understood. Methods: In this study, we performed high-throughput screening of mRNA expression profiles in 92 NPC samples collected from 3hospitals and detected the mRNA expression levels of 31,503 genes in these samples. Gene functional enrichment analyses were performed using gene set enrichment analysis (GSEA). Least absolute shrinkage and selection operator (LASSO) was applied to select prognostic genes and a Cox proportional hazards regression model including these genes was constructed to predict prognosis. The Kaplan-Meier curve and time-dependent receiver operating characteristic (ROC) curve were plotted to assess the performance of this model. Univariate and multivariate analyses were performed using the Cox proportion hazard model to test the independence of prognostic effect of gene model and other clinical features. Results: A total of 1837 differentially expressed genes between patients with and without distant metastasis were identified in the training cohort, including 869 upregulated genes and 968 downregulated genes. Six gene sets, including the Wnt/ß catenin signaling pathway, hedgehog (Hh) signaling pathway, Notch signaling pathway, mitotic spindle, apical surface, and estrogen response late, were enriched in patients with distant metastasis. A four-gene signature model was constructed in the training cohort, and according to the time-dependent ROC curve, this model had certain accuracy in predicting distant metastasis-free survival (DMFS) in both the training and validation cohorts. Conclusion: We developed a four-gene signature model that can evaluate the distant metastasis risk of NPC patients and may also provide novel therapeutic targets for NPC treatment in the near future.

Comparison of whole exome sequencing in circulating tumor cells of primitive and metastatic nasopharyngeal carcinoma.

BACKGROUND: Nasopharyngeal carcinoma (NPC) is one of the most common cancers. To investigate the gene mutation profile of NPC patients, we performed whole exome sequencing (WES) in tumor cells, peripheral blood cells, and circulating tumor cells (CTCs) of primitive and metastatic NPC patients, and explored its clinical significance. METHODS: Primitive tumor cells, white blood cells, and CTCs of patients were collected and hybridized with probes targeting whole exons. Mutational signatures, signaling pathways, and cancer associated genes from CTCs cells of two primitive and two metastatic patients were analyzed using gene ontology (GO) method. RESULTS: The mutational landscape of four primitive tumors showed that there were more MSH2 alterations in more non-silent mutation number patients Additionally, BAP1 gene mutation only occurred in metastatic patients. The most frequently mutated genes among the primitive tumor and CTC samples were CFAP74, MOB3C, PDE4DIP, IGFN1, CYFIP2, NOP16, SLC22A1, ZNF117, and SSPO. Interestingly, only PMS1, BRIP1, DEE, OR2T12, CPN2, MLXIPL, BAIAP3, IGSF3, SIN3B, and ZNF880 alterations occurred in primary tumors of metastatic patients. Primitive and metastatic NPC had significantly distinct mutational signatures. GO analysis revealed that each patient had his own mutational signaling pathways. Non-silent single nucleotide variations (non-silent SNVs) and insertion-deletion mutations (INDELs) in CTCs were more dramatic than in primitive tumor cells. CONCLUSIONS: These changes are strongly relevant to their clinical characteristics and therapeutic strategy.

Up-regulation of the IRX2 gene predicts poor prognosis in nasopharyngeal carcinoma.

Aberrant expression of the IRX2 gene contributes to the oncogenesis and progression of various cancers. In this study, we analyzed the clinical significance and the prognostic value of mRNA expression level of the IRX2 gene in nasopharyngeal carcinoma (NPC) patients, with the goal to find a novel prognostic biomarker for NPC. Tissue samples were collected prior to treatment from 71 NPC patients for the detection of mRNA expression level of a total of 31503 genes, with high throughput screening of the mRNA expression profile. The Kaplan-Meier curves and log-rank test were used for univariate analyses to determine if the mRNA expression level of IRX2 and other 31502 genes, as well as clinical characteristics were of prognostic value for overall survival (OS), distant metastasis-free survival (DMFS) and disease-free survival (DFS). Regularized Cox regression was performed to test the contribution of prognostic factors to OS, DMFS, and DFS of NPC patients. The Cox proportional hazard model was used to test the independence of prognostic effect of IRX2 and other clinical features. The receiver operator characteristic curve was drawn and the area under the curve (AUC) was calculated to evaluate the predictive power of IRX2 gene. Univariate analyses showed a higher mRNA expression level of the IRX2 gene correlated with shorter OS (P = 0.001), DMFS (P = 0.003), and DFS (P = 0.007). Regularized Cox regression and Cox proportional hazard model analyses further showed that ahigher mRNA expression level of the IRX2 gene in the primary NPC was an independent prognostic factor for OS (Coxnet beta = 0.03, Cox proportion hazard model P = 0.038), DMFS (Coxnet beta = 0.018, Cox proportion hazard model P = 0.01) and DFS (Coxnet beta = 0.008, Cox proportion hazard model P = 0.029). The AUC showed that the mRNA expression level of the IRX2 gene is a significant predictor for predicting the OS (AUC value = 0.7105) and DMFS (AUC value = 0.7027) of NPC patients. Our results demonstrated that the IRX2 gene may be a novel independent unfavorable prognostic factor for NPC patients.

Correlation of metastasis-associated protein expression with prognosis and chemotherapy in nasopharyngeal carcinoma.

The aim of this study was to elaborate the correlation between metastasis-associated protein (MTA) family and the occurrence, progression, prognosis and chemotherapy efficiency in nasopharyngeal carcinoma (NPC).The expression of MTA1, MTA2 and MTA3 protein were detected by immunohistochemistry in a tissue microarray (TMAs) which contains tissue samples of 152 NPC patients embedded by formalin-fixed paraffin. The MTA proteins were mainly expressed in the nuclei of NPC tissues and the correlations between MTAs expression and clinical parameters as well as prognosis of NPC patients showed ethnical differences according to statistically analysis. The results showed that in Han ethnic group, MTA1 expression was positively correlated with N staging, while the expression of MTA2 was negatively correlated with age, and the expression of MTA3 was positively correlated with gender. Patients with high MTA1 expression had poorprognosis. In Zhuang ethnic group, only MTA3 expression was positively correlated with age, recurrence and metastasis of NPC patients; neither MTA1 nor MTA2 expression had any correlation with clinical indexes. Patients with high MTA3 expression had unfavorable prognosis. In addition, our results showed that overall survival among Zhuang NPC patients with low expression of MTA2 increased significantly owing to "carboplatin + fluorouracil" chemotherapy. This therapeutic success, however, did not translate to longer overall survival among Han NPC patients. The biological function of MTA protein family in NPC patients was different among different ethnic groups. In conclusion, we demonstrated that MTAs had a certain tumor promoting function in patients with NPC, and the biological functions of MTAs might be ethnic differences, which suggesting MTAs to be important markers for guiding clinical treatment of NPC.

[The clinical experience of transnasal endoscopic approach for skull base osteoradionecrosis after radiotherapy for nasopharyngeal carcinoma].

OBJECTIVE: To investigate the method of surgical treatment via trans-nasal endoscopic approach in osteoradionecrosis of skull base after radiotherapy for nasopharyngeal carcinoma. METHODS: Fifteen patients with osteoradionecrosis of skull base after radiotherapy for nasopharyngeal carcinoma who underwent operation via trans-nasal endoscopic approach from 2008 to 2013 were retrospectively reviewed. The typical clinical manifestations included headache (NRS 6-9: 11 cases), foul odor (10 cases), epistaxis (4 cases), hearing loss (5 cases, 7 ears), tinnitus (4 cases, 5 ears). All patients underwent operation via trans-nasal endoscopic approach. During the operation, the diseased region was fully exposed, the necrotic tissue was resected, the necrotic bone was removed by high-speed electric drill, and the drainage was made unobstructed. The perioperative treatment and follow-up were carried out. RESULTS: After operation, all patients were diagnosed pathologically as osteoradionecrosis and mucosal chroinic inflammation, 1 case combined with fungal sphenoid sinusitis. Headache (9 cases) and foul odor (9 cases) resolved after operation. The follow-up was lasted 18-82 months, 13 cases were survival, 1 case lost to follow-up, 1 case died of cerebral hemorrhage. CONCLUSION: Surgical treatment via trans-nasal endoscopic approach is safe and effective in osteoradionecrosis of skull base after radiotherapy for nasopharyngeal carcinoma, and is helping to improve the survival rate and survival quality.

[Treatment and outcome of recurrent cervical lymph nodes in patients with nasopharyngeal carcinoma after radiotherapy].

OBJECTIVE: To evaluate the efficacies of different treatments for recurrent cervical lymph nodes and the factors contributing to prognosis in patients with nasopharyngeal carcinoma after radiotherapy. METHODS: Clinical data of 79 patients with nasopharyngeal carcinoma after radiotherapy were retrospectively analyzed, and all cases were diagnosed as having recurrent cervical lymph nodes by pathological examination. The factors including sex, age, the interval between completion of radiotherapy and recurrence, rN stage, treatment methods, and the location relationship between recurrent lesion and primary tumor in the neck were analyzed for prognosis. Kaplan-Meier curves, Log-rank test and Cox's proportional hazards regression mode were used in the statistical analysis. RESULTS: The median recurrence time was 26 months, and the 1- , 3- and 5-year overall survival rates were 77.9%, 53.4% and 39.7%. Cox's proportional hazards regression mode analysis indicated that age, rN stage, treatment methods, and the location relationship between recurrent lesion and primary tumor were significantly prognostic factors. CONCLUSIONS: Neck dissection is superior to re-radiotherapy in treatment of recurrent cervical lymph nodes in nasopharyngeal carcinoma after radiotherapy. The patients younger than 45 years old, in early rN stage and for recurrence in the center region of primary tumor have a better prognosis.

[Analyses of therapeutic and prognostic factors for rN3 neck recurrence of nasopharyngeal carcinoma after primary radiotherapy].

OBJECTIVE: To investigate the treatment and prognosis for rN3 neck recurrence of nasopharyngeal carcinoma (NPC) after primary radiotherapy. METHODS: A total of 37 cases with rN3 neck recurrence after radiotherapy in NPC between October 2003 and August 2013 were retrospectively analyzed. Of them 19 cases presented with lymph node (LN) metastasis in supraclavicular fossa, 18 cases had metastasis LN > 6 cm, 10 cases received chemoradiotherapy, and 27 cases underwent neck dissection including modified radical neck dissection (MRND) for 9 cases, radical neck dissection (RND) for 18 cases. Six of 18 cases with RND underwent reconstructive surgery with pectoralis major flap, 12 cases received postoperative radiotherapy and 20 cases had postoperative adjuvant chemotherapy. RESULTS: Eight patients had documented recurrence or residue, 17 patients developed distant metastases, one patient showed recurrence and distant metastasis. The 5-year overall survival rate and disease-free survival rate were 27.5% and 21.6% respectively, and the median survival time was 41 months. The survival rate in surgery group was significantly higher than that in chemoradiotherapy group, and the prognosis of patients with LN > 6 cm was better than that of patients with metastasis LN to supraclavicular fossa. CONCLUSIONS: Patients with rN3 NPC are prone to metastasis, and patients with supraclavicular fossa lymph node metastasis had poor prognosis. Surgery combined with chemoradiotherapy is an effective treatment for the patients without distant metastasis.

[Application of narrow band imaging endoscopy in early diagnosis of nasopharyngeal carcinoma].

OBJECTIVE: To investigate the use of NBI (narrow band imaging) in early the diagnosis of nasopharyngeal carcinoma. METHODS: A total of 55 cases with nasopharyngeal lesions (including 9 cases of nasopharyngeal carcinoma after treatment) were examined and diagnosed by white and NBI endoscopy between October 2011 and March 2012, and their diagnosis efficacies were evaluated based on pathological diagnosis as a gold standard. Chi-square test was used to analyze data. RESULTS: Of 55 cases, 12 cases were pathologically diagnosed as chronic mucosa inflammation and 43 as nasopharyngeal carcinoma including 6 recurrent cases, of 43 cases, 40(93.0%) were diagnosed by NBI endoscopy and 18 (41.9%) by white endoscopy. Of 12 cases with early nasopharyngeal carcinoma (5 for stage I and 7 for stage II) , 5(100.0%) for stage I, and 6(85.7%) for stage II were diagnosed by NBI endoscopy but only 1(14.3%) for stage II by white endoscopy, with a statistically significant difference (χ(2) = 10.000, P = 0.008;χ(2) = 7.143, P = 0.029). CONCLUSION: NBI endoscopy can be used in early diagnosis of nasopharyngeal carcinoma and check after treatment.

[Choice of surgical approaches for salvage surgery of primary lesion recurrence and residual cases of nasopharyngeal carcinoma].

OBJECTIVE: The choice of surgical approaches for salvage surgery based on the location and invasion of recurrent and residual lesions of nasopharyngeal carcinoma (NPC), surgical results, complications, and survival were assessed. METHODS: Thirty-seven cases with recurrent and residual lesions of NPC underwent salvage surgery between March 1991 and January 2005 were analysed retrospectively. Of 37 patients, 23 were men and 14 women, with a median age of 46.5 years (26 - 57 years); 4 were at stage I, 10 at stage II, 14 at stage III, and 9 at stage IV; 5 cases were with cervical metastasis, including 3 cases of N1 and 2 cases N2. All recurrent and residual lesions of NPC were determined by biopsy. On the location and invasion of recurrent and residual lesions of NPC, 8 cases underwent endoscopic resection of lesions, 12 cases of the palate nasopharyngectomy, 5 cases of maxillary swing, 4 cases of maxillary swing plus prerenal approach, 2 cases of lateral rhinotomy plus coronal flap approach, and 6 cases transfacial plus nasal pyramid swing approach. Five cases with cervical metastasis received neck dissection in addition to the operations for recurrent and residual lesions of NPC. Postoperatively 31 cases received radiotherapy with dosage of 60 Gy, among them 15 cases with concurrent chemoradiation therapy, and 6 cases with clear surgical margin did not received radiotherapy or chemotherapy. The cases were followed up for 12 - 72 months, with a median of 45 months. RESULTS: Total resection for the recurrent and residual lesions of NPC accounted for 91.8% (34/37) and subtotal resection for 8.2% (3/37). The accident of perioperative complications was 24.3% (9/37). The 3- and 5-year overall disease-free survival rates (DFSR) were 62.1% and 43.3%, respectively. The 3- and 5-year overall survival rates (OSR) were 72.9% and 51.3%, respectively. The 5 year DFSR of cases at stage I-IV were 100%, 40%, 28% and 11% (χ(2) = 10.0, P < 0.01), respectively. The 5 year OSR were 100%, 70%, 35% and 28% (χ(2) = 11.5, P < 0.01), respectively. CONCLUSIONS: Salvage surgery is a justified treatment for the recurrent and residual lesions of NPC, by which some patients with recurrent and residual lesions of NPC can be salvaged.

[Relationship between expression of multidrug-resistant genes in nasopharyngeal carcinoma tissue and sensitivity to chemotherapy].

OBJECTIVE: To study the relationship between multidrug-resistant (MDR) expression in nasopharyngeal carcinoma (NPC) and its sensitivity to chemotherapy. METHODS: The specimens of 23 NPC cases were studied by immunohistochemistry with monoclonal antibody of P-glycoprotein (P-gp), multidrug resistance relation protein (MRP), lung-resistance related protein (LRP), topoisomerase II (Topo II), thymidylate synthase (TS), glutathione-S-transferase (GST-pi). Among them, 20 specimens were taken from primary NPC lesion which were treated with two course of cisplatin (DDP) and 5-fluorouracil (5-FU), 3 specimens were taken from cervical lymph-node of recurrent NPC patients who were treated by radical dissection. RESULTS: Various MDR parameters were expressed differently in 22 cases except for 1 clear cell carcinoma case. The difference was statistically significant (P < 0.05). However, there were no significant difference of MDR expression either among various carcinoma pathomorphology cell groups or among different clinical stage groups. Expression of LRP and TS were found in 10 and 14 cases respectively and the chemotherapy responders rates were 20% (2/10) and 28.5% (4/14) respectively. While the chemotherapy responders rates were 70% (7/10) and 5/6 in cases without expression. There was significant difference (P < 0.001, and P < 0.05). CONCLUSION: The NPC patients with LRP and TS expression may be less sensitive to chemotherapy with DDP + 5-FU.