Radiotherapy For Nasopharyngeal Carcinoma Research Articles

A knowledge-based intensity-modulated radiation therapy treatment planning technique for locally advanced nasopharyngeal carcinoma radiotherapy

BackgroundTo investigate the feasibility of a knowledge-based automated intensity-modulated radiation therapy (IMRT) planning technique for locally advanced nasopharyngeal carcinoma (NPC) radiotherapy.MethodsOne hundred forty NPC patients treated with definitive radiation therapy with the step-and-shoot IMRT techniques were retrospectively selected and separated into a knowledge library (n = 115) and a test library (n = 25). For each patient in the knowledge library, the overlap volume histogram (OVH), target volume histogram (TVH) and dose objectives were extracted from the manually generated plan. 5-fold cross validation was performed to divide the patients in the knowledge library into 5 groups before validating one group by using the other 4 groups to train each neural network (NN) machine learning models. For patients in the test library, their OVH and TVH were then used by the trained models to predict a corresponding set of mean dose objectives, which were subsequently used to generate automated plans (APs) in Pinnacle planning system via an in-house developed automated scripting system. All APs were obtained after a single step of optimization. Manual plans (MPs) for the test patients were generated by an experienced medical physicist strictly following the established clinical protocols. The qualities of the APs and MPs were evaluated by an attending radiation oncologist. The dosimetric parameters for planning target volume (PTV) coverage and the organs-at-risk (OAR) sparing were also quantitatively measured and compared using Mann-Whitney U test and Bonferroni correction.ResultsAPs and MPs had the same rating for more than 80% of the patients (19 out of 25) in the test group. Both AP and MP achieved PTV coverage criteria for no less than 80% of the patients. For each OAR, the number of APs achieving its criterion was similar to that in the MPs. The AP approach improved planning efficiency by greatly reducing the planning duration to about 17% of the MP (9.85 ± 1.13 min vs. 57.10 ± 6.35 min).ConclusionA robust and effective knowledge-based IMRT treatment planning technique for locally advanced NPC is developed. Patient specific dose objectives can be predicted by trained NN models based on the individual’s OVH and clinical TVH goals. The automated planning scripts can use these dose objectives to efficiently generate APs with largely shortened planning time. These APs had comparable dosimetric qualities when compared to our clinic’s manual plans.

Salivary glands and dental complications after radiotherapy for nasopharyngeal carcinoma

Salivary glands and dental complications after radiotherapy for nasopharyngeal carcinoma

Analysis of Prognostic Risk Factors in Patients with Nasopharyngeal Carcinoma Treated with Radiotherapy by Magnetic Resonance Imaging

The purpose of the study was to explore the application value of magnetic resonance imaging (MRI) technology in the study of the prognosis of patients with nasopharyngeal carcinoma (NPC) after radiotherapy, and to analyze the risk factors leading to imaging residues, so as to provide reference for the treatment and prognosis of patients with NPC. The clinical data of 691 patients with NPC hospitalized from June 2008 to June 2016 were retrospectively analyzed. According to the results of magnetic resonance medical imaging, the residual data of patients with NPC after treatment were analyzed. Combined with t-stage and n-stage parameters, the image residual was divided into t-stage residual and n-stage residual. The radiological residues, residual regression time, survival time, recurrence and metastasis time were recorded. The radiological residual rate of NPC after radiotherapy was calculated, and the differences among groups were compared by chi-square test. The risk factors of image residual and residual regression time were analyzed by logistic regression model. The 5-year overall survival rate (OS), 5-year recurrence-free survival rate (LRFS), and 5-year distant metastasis-free survival rate (DMF) were calculated. Kaplan.Meier method was used to analyze the influence of various factors on the prognosis of patients, and logarithmic rank test was used to compare the difference of survival rate between the two groups. The results showed that the residual rate of T and N was 32.9% and 31.0% at the end of radiotherapy for NPC. In summary, magnetic resonance medical imaging technology can effectively evaluate the prognostic risk factors of patients with NPC after radiotherapy. Male, elderly, radioactivity residue, and high stage are the risk factors affecting the prognosis of patients with NPC after radiotherapy. The recurrence and metastasis of NPC patients can be effectively controlled by means of emphasizing radiotherapy combined with adjuvant chemotherapy.

Sequential and Iterative Auto-Segmentation of High-Risk Clinical Target Volume for Radiotherapy of Nasopharyngeal Carcinoma in Planning CT Images.

Background: Accurate segmentation of tumor targets is critical for maximizing tumor control and minimizing normal tissue toxicity. We proposed a sequential and iterative U-Net (SI-Net) deep learning method to auto-segment the high-risk primary tumor clinical target volume (CTVp1) for treatment planning of nasopharyngeal carcinoma (NPC) radiotherapy.Methods: The SI-Net is a variant of the U-Net architecture. The input of SI-Net includes one CT image, the CTVp1 contour on this image, and the next CT image. The output is the predicted CTVp1 contour on the next CT image. We designed the SI-Net, using the left side to learn the volumetric features and the right to localize the contour on the next image. Two prediction directions, one from inferior to superior (forward direction) and the other from superior to inferior (backward direction), were tested. The performance was compared between the SI-Net and the U-Net using Dice similarity coefficient (DSC), Jaccard index (JI), average surface distance (ASD), and Hausdorff distance (HD) metrics.Results: The DSC and JI values from the forward direction SI-Net model were 5 and 6% higher than those from the U-Net model (0.84 ± 0.04 vs. 0.80 ± 0.05 and 0.74 ± 0.05 vs. 0.69 ± 0.05, p < 0.001). The smaller ASD and HD values also indicated a better performance (2.8 ± 1.0 vs. 3.3 ± 1.0 mm and 8.7 ± 2.5 vs. 9.7 ± 2.7 mm, p < 0.01) for the SI-Net model. For the backward direction SI-Net model, the DSC and JI values were still better than those from the U-Net model (p < 0.01), although there were no significant differences in ASD and HD.Conclusions: The SI-Net model preserved the continuity between adjacent images and thus improved the segmentation accuracy compared with the conventional U-Net model. This model has potential of improving the efficiency and consistence of CTVp1 contouring for NPC patients.

Radio-Susceptibility of Nasopharyngeal Carcinoma: Focus on Epstein- Barr Virus, MicroRNAs, Long Non-Coding RNAs and Circular RNAs.

Nasopharyngeal carcinoma (NPC) is a type of head and neck cancer. As a neoplastic disorder, NPC is a highly malignant squamous cell carcinoma that is derived from the nasopharyngeal epithelium. NPC is radiosensitive; radiotherapy or radiotherapy combining with chemotherapy are the main treatment strategies. However, both modalities are usually accompanied by complications and acquired resistance to radiotherapy is a significant impediment to effective NPC therapy. Therefore, there is an urgent need to discover effective radio-sensitization and radio-resistance biomarkers for NPC. Recent studies have shown that Epstein-Barr virus (EBV)-encoded products, microRNAs (miRNAs), long non-coding RNAs (lncRNAs) and circular RNAs (circRNAs), which share several common signaling pathways, can function in radio-related NPC cells or tissues. Understanding these interconnected regulatory networks will reveal the details of NPC radiation sensitivity and resistance. In this review, we discuss and summarize the specific molecular mechanisms of NPC radio-sensitization and radio-resistance, focusing on EBV-encoded products, miRNAs, lncRNAs and circRNAs. This will provide a foundation for the discovery of more accurate, effective and specific markers related to NPC radiotherapy. EBVencoded products, miRNAs, lncRNAs and circRNAs have emerged as crucial molecules mediating the radio-susceptibility of NPC. This understanding will improve the clinical application of markers and inform the development of novel therapeutics for NPC.

Magnetic resonance-based synthetic computed tomography images generated using generative adversarial networks for nasopharyngeal carcinoma radiotherapy treatment planning

Background and purposeTo investigate the feasibility of synthesizing computed tomography (CT) images from magnetic resonance (MR) images using generative adversarial networks (GANs) for nasopharyngeal carcinoma (NPC) intensity-modulated radiotherapy (IMRT) planning. Materials and methodsConventional T1-weighted MR images and CT images were acquired from 173 NPC patients. The MR and CT images of 28 patients were randomly chosen as the independent tested set. The remaining images were used to build a conditional GAN (cGAN) and a cycle-consistency GAN (cycleGAN). A U-net was used as the generator in cGAN, whereas a residual-Unet was used as the generator in cycleGAN. The cGAN was trained using the deformable registered MR-CT image pairs, whereas the cycleGAN was trained using the unregistered MR and CT images. The generated synthetic CT (SCT) images from cGAN and cycleGAN were compared with the true CT images with respect to their Hounsfield Unit (HU) discrepancy and dosimetric accuracy for NPC IMRT plans. ResultsThe mean absolute errors within the body were 69.67 ± 9.27 HU and 100.62 ± 7.39 HU for the cGAN and cycleGAN, respectively. The 2%/2-mm γ passing rates were (98.68 ± 0.94)% and (98.52 ± 1.13)% for the cGAN and cycleGAN, respectively. Meanwhile, the absolute dose discrepancies within the regions of interest were (0.49 ± 0.24)% and (0.62 ± 0.36)%, respectively. ConclusionBoth cGAN and cycleGAN could swiftly generate accurate SCT volume images from MR images, with high dosimetric accuracy for NPC IMRT planning. cGAN was preferable if high-quality MR-CT image pairs were available.

Radiation-induced second primary squamous cell carcinoma of the oral cavity after radiotherapy for nasopharyngeal carcinoma.

The increasing occurrence of radiation-induced second primary squamous cell carcinoma of the oral cavity (RISCCO) after radiotherapy for nasopharyngeal carcinoma (NPC) has become a noteworthy complication that can influence long-term survival. This study aimed to analyze the associations of clinicopathologic characteristics with prognostic factors among patients who developed RISCCO after radiotherapy for NPC. A total of 41,446 NPC patients admitted to Sun Yat-sen University Cancer Center (SYSUCC) between August 1989 and January 2019 were reviewed. Among these patients, 88 RISCCO patients who satisfied the inclusion criteria were included in the study. During our study, the incidence of RISCCO after radiotherapy was 0.21% (88/41,446) among NPC patients at SYSUCC. The latency period ranged from 1.0 to 34.0years (median, 9.0years), and the latency of RISCCO was notably shorter for patients who received intensity-modulated radiation therapy than that for patients who received conventional radiotherapy using cobalt-60 or 6-MV X-rays (median, 4.0years vs. 11.0years, P=0.013). The 1-, 3-, and 5-year overall survival (OS) rates for the entire cohort of 88 patients were 79.0%, 46.6%, and 35.2%, respectively. The 5-year OS rate for the 79 patients who received treatment was 45.7%, and the 5-year OS rate for the 9 patients who refused treatment was 0%. T classification and surgery were identified as independent prognostic factors associated with a high OS rate. Surgery as the first-choice treatment may improve survival and prognosis. A long-term follow-up is needed for early detection of RISCCO in NPC patients.

Late side effects of radiation treatment for head and neck cancer.

Patients undergoing radiation therapy for head and neck cancer (HNC) experience significant early and long-term side effects. The likelihood and severity of complications depends on a number of factors, including the total dose of radiation delivered, over what time it was delivered and what parts of the head and neck received radiation. Late side effects include: permanent loss of saliva; osteoradionecrosis; radiation recall myositis, pharyngoesophageal stenosis; dental caries; oral cavity necrosis; fibrosis; impaired wound healing; skin changes and skin cancer; lymphedema; hypothyroidism, hyperparathyroidism, lightheadedness, dizziness and headaches; secondary cancer; and eye, ear, neurological and neck structures damage. Patients who undergo radiotherapy for nasopharyngeal carcinoma tend to suffer from chronic sinusitis. These side effects present difficult challenges to the patients and their caregivers and require life-long strategies to alleviate their deleterious effect on basic life functions and on the quality of life. This review presents these side effects and their management.

Qualitative study of continuing nursing needs in patients with precision radiotherapy for nasopharyngeal carcinoma

AbstractObjectiveTo explore the inner feelings and experiences of patients with precision radiotherapy for nasopharyngeal carcinoma after discharge on continue nursing needs, and to provide theoretical basis for the development of continuing nursing service for patients with nasopharyngeal carcinoma.MethodBy using the phenomenological analysis in qualitative research, face‐to‐face semistructured in‐depth interviews were conducted on 10 nasopharyngeal carcinoma (NPC) patients who received precision radiotherapy, and the data analysis was carried out by phenomenological analysis method, Colaizzi method.ResultsThe continuing nursing needs of 10 NPC patients after discharge may be summarized under four main categories: expectation of disease prognosis and self‐care related knowledge, expectation of professional psychological counseling and mental care, strong willingness to seek social and family support, and expectation of accessible health services resources.ConclusionIt is urgent to establish an effective continuous nursing service channel to meet the physical and mental needs of patients with nasopharyngeal carcinoma after discharge, and to continuously improve the life quality of patients with nasopharyngeal carcinoma.

LINAC-based Fractionated Stereotactic Radiotherapy for Residual and Recurrent Nasopharyngeal Carcinoma in the Era of Intensity-modulated Radiotherapy: A 10-year Experience

LINAC-based Fractionated Stereotactic Radiotherapy for Residual and Recurrent Nasopharyngeal Carcinoma in the Era of Intensity-modulated Radiotherapy: A 10-year Experience

Abstract B06: Repositioning the FDA-approved antiviral drug ribavirin as targeted therapy for nasopharyngeal carcinoma

Abstract Purpose: Nasopharyngeal carcinoma (NPC) is a squamous cell carcinoma that is often diagnosed at an advanced stage, leading to poor disease-free and overall survival. Accumulating literature suggests that elevated protein expression of enhancer of zeste homolog 2 (EZH2), eukaryotic initiation factor 4E (eIF4E), and inosine-5’-monophosphate dehydrogenase (IMPDH)—proteins implicated in myriad cancers—correlates with poor prognosis in NPC. These three proteins are modulated by the Food and Drug Administration-approved antiviral drug ribavirin, which has recently been repositioned by our laboratory and others as a promising anticancer agent. Based on this intersection of molecular signature and drug targets, we investigated the potential of ribavirin as a therapeutic agent for NPC. Experimental Design: We assessed antineoplastic efficacy of ribavirin on six human NPC cell lines in vitro using cellular growth assays, flow cytometry, and scratch wound assays. Mechanistic pathways involved were investigated using genomic expression datasets, Western blots, and enzymatic activity assays. The effects of combining ribavirin with radiation were assessed using clonogenic assays and flow cytometry. Finally, we evaluated the effects of ribavirin on tumor growth in vivo using two human cell line-derived xenograft models. Results: Ribavirin significantly decreased NPC cellular proliferation and migratory capacity in addition to promoting cell cycle arrest and cell death. Modulation of the EZH2, Snail, eIF4E, and IMPDH pathways was observed in response to ribavirin treatment. Ribavirin significantly enhanced the cytotoxic effects of radiation therapy in NPC. Most importantly, ribavirin significantly reduced flank tumor growth in two NPC xenograft models. Conclusions: Our work suggests that ribavirin has potent anticancer effects in NPC and could represent a safe and promising addition to current NPC treatment regimens. Citation Format: Sakibul Huq, Joshua Casaos, Michael Peters, Yuanxuan Xia, Andy Ding, Manuel Morales, Noah Gorelick, Riccardo Serra, Tianna Zhao, Wataru Ishida, Alexander Perdomo-Pantoja, Arba Cecia, Chenchen Ji, Ian Suk, David Sidransky, Mariana Brait, Henry Brem, Nicolas Skuli, Betty Tyler. Repositioning the FDA-approved antiviral drug ribavirin as targeted therapy for nasopharyngeal carcinoma [abstract]. In: Proceedings of the AACR-AHNS Head and Neck Cancer Conference: Optimizing Survival and Quality of Life through Basic, Clinical, and Translational Research; 2019 Apr 29-30; Austin, TX. Philadelphia (PA): AACR; Clin Cancer Res 2020;26(12_Suppl_2):Abstract nr B06.

Transnasal endoscopic surgery of choanal atresia after radiotherapy for nasopharyngeal carcinoma

Objective: To discuss the effect of endoscopic dilatation and plasty for choanal atresia after radiotherapy for nasopharyngeal carcinoma. Methods: Nineteen patients with choanal atresia who were admitted to the Department of Otorhinolaryngology Head and Neck Surgery of the First Affiliated Hospital of Nanchang University from Jan. 2011 to Dec. 2018 were reviewed, with 12 males and 7 females aging from 33 to 59 years old. All of the patients had a history of radiotherapy for nasopharyngeal carcinoma and were confirmed by electronic nasopharyngoscope and nasopharyngeal imaging. Among 19 patients, there were 3 cases of unilateral occlusion and 16 cases with bilateral atresia, and all of them were membranous atresia. All patients received the transnasal endoscopic surgery of resecting partial vomer bone while trying to keep normal mucosa tissues and using the septonasal mucoperiosteal flap to repair under general anesthesia. One week after operation, the patients were told to do physiological saline nasal irrigation and received regular clean and observation under endoscope. Descriptive statistical method was used to analyze the outcome. Results: The patients were followed up for 1 year postoperatively by electronic nasopharyngoscopic examination. There was no failure case in all the 19 patients including 16 patients with a wide choana and 3 patients had narrowing of the choana (<50%), with adequate and satisfactory airway. Conclusions: Transnasal endoscopic surgery was an effective treatment for choanal atresia after radiotherapy for nasopharyngeal carcinoma. Application of septonasal mucoperiosteal flap for repairing nasal and nasopharyngeal mucosa would avoid recurrence.

Evaluation of automatic VMAT plans in locally advanced nasopharyngeal carcinoma.

This study aimed to evaluate the quality of locally advanced nasopharyngeal carcinoma (NPC) radiotherapy plans generated by the automated planning module of acommercial treatment planning system (TPS). Data of 30patients with locally advanced NPC were retrospectively investigated. For each patient, volumetric modulated arc therapy (VMAT) plans with double arcs were generated manually by experienced physicists and automatically in the Pinnacle3 Auto-Planning module (Philips Medical Systems, Fitchburg, WI, USA). The anatomic distance between the second clinical target volume (CTV2) and the pons of the brainstem, and the Tcategory of disease were factored into the evaluation. Dosimetric verification was evaluated in terms of gamma pass rate. Target coverage, sparing of organs at risk (OARs), and monitor units were evaluated and compared between the manual and automatic VMAT plans. Not all treatment plans fully met the dose objectives for planning target volumes (PTVs) and OARs, particularly in T4 patients. Overall, automatic VMAT provides acomparable or superior plan quality to manual VMAT in most cases. In stratified analysis, plan quality is mainly independent on Tcategory but is also affected by anatomic distance. If the anatomic distance is less than 5 mm, the automatic VMAT plan quality is equal or even inferior to manual VMAT performed by experienced physicists. Conversely, if the anatomic distance is greater than 5 mm, the automatic VMAT plan quality is superior to manual VMAT. Gamma pass rates for quality assurance are similar between manual and automatic VMAT plans for the former case, but significantly higher in automatic VMAT for the latter. The selection of manual versus automatic VMAT planning in locally advanced NPC should be made individually based on the anatomic distance, rather than blindly and habitually, since automatic VMAT is not good enough to completely replace manual VMAT.

Hypothyroidism after radiotherapy for nasopharyngeal carcinoma

Hypothyroidism after radiotherapy for nasopharyngeal carcinoma

The role of artificial intelligence in nasopharyngeal carcinoma radiotherapy

The role of artificial intelligence in nasopharyngeal carcinoma radiotherapy

Knockdown of annexin VII enhances nasopharyngeal carcinoma cell radiosensitivity in vivo and in vitro.

Radioresistance leads to treatment failure in patients with nasopharyngeal carcinoma (NPC). Thus, enhancing the radiosensitivity of NPC cells would likely increase the effectiveness of radiotherapy. Annexin VII (Annexin A7, ANXA7) might be a tumor promoter in NPC but its functions in radiosensitivity remain unclear. NPC celllinesCNE2-shANXA7 and CNE2-pLKO.1 were generated and CNE2-shANXA7 nudemicexenograft tumormodels were established. The main effects and molecularmechanisms of ANXA7 knockdown in NPC radiosensitivity were studied in vitro and in vivo by analyzing cell viability, clonogenicity, apoptosis, cell cycle distribution, tumor radioresponse and immunohistochemistry assay. ANXA7 knockdown revealed potentially enhanced NPC cell radiosensitivity via apoptosis and increased the cell numberat the G2/M phase. In the xenograft model, NPC cells with ANXA7 knockdown were dramatically sensitive to irradiation and tumor growth was significantly suppressed. Compared to CNE2-pLKO.1 xenografts, CNE2-shANXA7 showed more γ-H2AX foci and less phospho-DNA PKcs. ANXA7 knockdown increased the radiosensitivity of NPC by enhancing apoptosis, modulating the cell cycle distribution into more radiosensitive phases, promoting DNA damage, and inhibiting repair. We showed that decreased ANXA7 levels enhanced radiosensitivity and provided insights into the therapeutic targets for NPC radiotherapy.

A phase II randomized clinical trial and mechanistic studies using improved probiotics to prevent oral mucositis induced by concurrent radiotherapy and chemotherapy in nasopharyngeal carcinoma.

e18568 Background: Earlier evidence has proven that probiotic supplements can reduce radiochemotherapy (CCRT) -induced oral mucositis (OM) in nasopharyngeal cancer (NPC). We have recently modified the ingredient of the probiotics by combining Bifidobacterium animalis, Lactobacillus plantarum, Lactobacillus rhamnosus and Lactobacillus acidophilus. This report includes the Phase II clinical trial to evaluate the effect of the modified probiotics along with mechanistic studies. Methods: We enrolled 85 patients with locally advanced NPC who were undergoing CCRT. The patients were randomized (1:1) to receive either probiotic mixture or placebo. The incidence of severe OM (grade 3 or higher) was the primary endpoint to document. We utilized a rat model. We collected rat’s samples from the tongue, blood and fecal and proximal colon tissues on a various days following treatment and tested for the mechanism of probiotics mixture on OM. Results: We found that patients taking the probiotic mixture showed significantly reduced OM. The incidences for Grade 0, 1, 2, 3 and 4 OM in the placebo group and the probiotic mixture group were 0%, 14.7%, 38.2%, 32.4%, and 14.7% and 13.9%, 36.1%, 25%, 22.2%, and 2.8%, respectively. Furthermore, patients in the probiotic mixture group showed lower reduction rate in CD3+ T cells (75.5% vs 81%, P &lt; 0.01), CD4+ T cells (64.53% vs 79.53%, P &lt; 0.01), and CD8+ T cells (75.59% vs 62.36%, P &lt; 0.01) compared with the placebo group. In the rat model, the control group rats showed more severe mucositis, increased histologic changes of the oral mucosa on the 7th, 14th and 21th day, with the 14th day most significant. CCRT also caused an enhanced inflammation response and cell apoptosis in tongue in the control group. Moreover, CCRT increased the intestinal permeability through reducing the zonula occludens-1(ZO-1) and Claudin-1 expression in colon tissues and increasing the inflammation factors in bloods. The structure of gut microbiota was also disturbed in the control group mainly with the increasing abundance of Bacteroidetes and decreasing abundance of Firmicutes. However, probiotics mixture ameliorated the severity of OM, decreased the inflammation response, cell apoptosis, intestinal permeability, and restored the structure of gut microbiota to normal. Conclusions: The modified probiotic mixture significantly reduces the severity of OM through enhancing the immune response of patients and modifying structure of gut microbiota. Clinical trial information: NCT03112837.

High Expression of hsa_circRNA_001387 in Nasopharyngeal Carcinoma and the Effect on Efficacy of Radiotherapy.

BackgroundNasopharyngeal carcinoma (NPC) is one of the most difficult cancers to be detected and treated. Hunting for novel cancer-specific biomarkers for NPC patients is helpful for timely diagnosis and clinical treatment of NPC.MethodsIn this study, high-throughput circRNA sequencing was used to screen the circRNAs with expression variation in NPC patients. qRT-PCR was used to detect the expression level of hsa_circRNA_001387 in the cancer tissues from 100 surgical patients, the peripheral blood samples from 100 radiotherapy patients and NPC cell lines. Based on clinical data of the patients, the relationship between hsa_circRNA_001387 and radiotherapy as well as antibody to Epstein–Barr (EB) virus was investigated. The use of this circRNA as a biomarker for NPC was also discussed.ResultsExpression of hsa_circRNA_001387 was significantly increased in the tumor tissues of NPC surgical patients, in the peripheral blood samples of NPC radiotherapy patients and in the NPC cell lines (P<0.01). Expression of hsa_circRNA_001387 was significantly elevated in patients with well-differentiated tumors, lymph node metastasis and distant metastases, stage III–IV, positive EB virus, or family history of NPC. hsa_circRNA_001387 was closely associated with the prognosis of the patients. The overall survival and progression-free survival were shorter in patients with high expression. Through univariate and multivariate analyses, it was found that hsa_circRNA_001387 was considered as an independent factor for the prognosis of NPC patients.ConclusionThis study reported for the first time that expression of hsa_circRNA_001387 is significantly upregulated, and it was also indicated that hsa_circRNA_001387 can be used as a novel biomarker for NPC.

Impact of hypo-salivation on severe tooth wear: A ten-year cohort of patients received radiotherapy for nasopharyngeal carcinoma

ObjectivesThis study was conducted to examine the tooth wear status of nasopharyngeal-carcinoma (NPC) patients who had received radiotherapy at least 5-year previously, and to investigate the salivary parameters that may be associated with the tooth wear. MethodsTooth wear status of NPC survivors were clinically assessed using the Exact Tooth Wear Index. A tooth was graded to have severe wear when more than one-third of its buccal/occlusal/lingual surface had dentine loss. At the subject-level, percentages of anterior/posterior/all teeth with severe wear were calculated. Age, number of teeth, flow-rate/buffering capacity/pH of stimulated whole (SWS) and parotid (SPS) saliva’s were collected. Correlation and multiple-linear regression tests were performed at the significance level α = 0.05. ResultSixty-eight participants (mean age of 60.0 ± 8.9), 697 anterior and 686 posterior teeth were examined with a mean of 10-years post-radiotherapy. Severe tooth wear was found in 63 (92.6 percent) participants, 288 anterior and 83 posterior teeth. The mean percentage of anterior/posterior/all teeth with severe wear were 42.3 ± 28.1, 14.5 ± 19.9 and 30.0 ± 21.7. Anterior teeth, particularly the incisal surface of central incisors were most affected. The mean flow-rate of SWS and SPS were 0.1 ± 0.1 ml/min and 0.03 ± 0.07 ml/min respectively. Thirty (44.1 percent) and 48 (70.6 percent) participants were found to have low/no buffering capacity of SWS and SPS respectively. Multiple-regression analyses revealed the SWS flow-rate was associated with the percentage of anterior teeth with severe wear (p=0.03). ConclusionAnterior tooth wear is a significant dental problem among NPC survivors and was associated with hypo-salivation. Clinical significancePatients with hypo-salivation should be being monitored for tooth wear particularly on the anterior teeth.

Utility of magnetic resonance imaging in determining treatment response and local recurrence in nasopharyngeal carcinoma treated curatively

BackgroundTo determine the optimal timing of the first Magnetic Resonance Imaging (MRI) scan after curative-intent radiotherapy (RT) for nasopharyngeal carcinoma (NPC), and evaluate the role of MRI in surveillance for locoregional recurrence (LRR).MethodsPatients with non-metastatic NPC treated radically who had at least one post-treatment MRI (ptMRI) done were included for analysis. ptMRI reports were retrospectively reviewed and categorised as complete response (CR), partial response/residual disease (PR) or indeterminate (ID). Patients with LRR were assessed to determine if initial detection was by MRI or clinical means. Univariable and multivariable Cox proportional hazard regression analysis were performed to identify independent factors associated with CR on ptMRIs.ResultsBetween 2013 and 2017, 262 eligible patients were analysed, all treated with Intensity Modulated Radiotherapy (IMRT). Median time from end of RT to the first ptMRI was 93 days (range 32–346). Of the first ptMRIs, 88 (33.2%) were CR, 133 (50.2%) ID, and 44 (16.6%) PR. A second ptMRI was done for 104 (78.2%) of 133 patients with ID status. In this group, 77 (57.9%) of the subsequent MRI were determined to be CR, 21(15.8%) remained ID and 6 (4.5%) PR. T1 tumour stage and AJCC stage I were associated with increased CR rates on first ptMRI on multivariable analysis. ID status was more likely at 75–105 days (3 months +/− 15 days) vs 106–135 days (4 months +/− 15 days) post RT (OR 2.13, 95% CI 1.16–4.12, p = 0.024). LRR developed in 27 (10.1%) patients; 20 (74.1%) were initially detected through MRI, 3 (11.1%) by nasoendoscopy and 2 (7.4%) by PET-CT.ConclusionMRI is useful for detecting local recurrence or persistent disease after curative-intent treatment. Most patients will need more than one ptMRI to arrive at a definitive status. The rate of ID ptMRI may be reduced by delaying the first scan to around 4 months post RT.