Intensity-modulated radiation therapy with or without chemotherapy for nasopharyngeal carcinoma: radiation therapy oncology group phase II trial 0225

Evaluation of daily dose accumulation with deformable image registration method using helical tomotherapy images for nasopharyngeal carcinoma

Aim:

Nasopharyngeal carcinoma (NPC) patients may have anatomical variations during their radiotherapy treatment course. In this study, we determine the daily accumulated dose by the deformable image registration (DIR) process for comparing with the planned dose and explore the number of fractions which the daily accumulated dose significantly changed from the planned dose.

Methods:

The validation of the DIR process in MIM software has been tested. One hundred and sixty-five daily megavoltage computed tomography (MVCT) images of NPC patients who were treated by helical tomotherapy were exported to MIM software to determine the daily accumulated dose and then compared with the planned dose.

Results:

The MIM software illustrated the acceptable validation for clinical application. The accumulated dose (D50%) of the planning target volume (PTV70) showed a decrease from the planned dose with an average of 0.5 ± 0.27% at the end of the treatment and was significantly different from the planned dose after the second fraction of the treatment (p-value = 0.008). In contrast, the accumulated dose of organ at risk (OAR) tended to increase from the planned dose and was significantly different after the fifth fraction (left parotid), the twelfth fraction (right parotid) and the second fraction (spinal cord).

Findings:

The inter-fractional anatomic changes cause the actual dose to be different from the planned dose. The dose differences and the number of fractions were varied in each target and OAR. The dose accumulation explored the necessary information for the radiation oncologist to consider adaptive treatment strategies to increase the efficiency of treatment.

Liquid biopsy posttreatment surveillance in endemic nasopharyngeal carcinoma: a cost-effective strategy to integrate circulating cell-free Epstein-Barr virus DNA

BACKGROUND

The optimal posttreatment surveillance strategy for nasopharyngeal carcinoma (NPC) remains unclear. Circulating cell-free Epstein-Barr virus (cfEBV) DNA has been recognized as a promising biomarker to facilitate early detection of NPC recurrence. Therefore, we aim to determine whether integrating circulating cfEBV DNA into NPC follow-up is cost-effective.

METHODS

For each stage of asymptomatic nonmetastatic NPC patients after complete remission to primary NPC treatment, we developed a Markov model to compare the cost-effectiveness of the following surveillance strategies: routine follow-up strategy, i.e., (1) routine clinical physical examination; routine imaging strategies, including (2) routine magnetic resonance imaging plus computed tomography plus bone scintigraphy (MRI + CT + BS); and (3) routine 18F-fluorodeoxyglucose positron emission tomography/computed tomography (PET/CT); cfEBV DNA-guided imaging strategies, including (4) cfEBV DNA-guided MRI + CT + BS and (5) cfEBV DNA-guided PET/CT. Clinical probabilities, utilities, and costs were derived from published studies or databases. Sensitivity analyses were performed.

RESULTS

For all disease stages, cfEBV DNA-guided imaging strategies demonstrated similar survival benefits but were considerably more economical than routine imaging strategies. They only required approximately one quarter of the number of imaging studies compared with routine imaging strategies to detect one recurrence. Specifically, cfEBV DNA-guided MRI + CT + BS was most cost-effective for stage II (incremental cost-effectiveness ratio [ICER] $57,308/quality-adjusted life-year [QALY]) and stage III ($46,860/QALY) patients, while cfEBV DNA-guided PET/CT was most cost-effective for stage IV patients ($62,269/QALY). However, routine follow-up was adequate for stage I patients due to their low recurrence risk.

CONCLUSIONS

The cfEBV DNA-guided imaging strategies are effective and cost-effective follow-up methods in NPC. These liquid biopsy-based strategies offer evidence-based, stage-specific surveillance modalities for clinicians and reduce disease burden for patients.

Significant Reduction in Vertebral Artery Dose by Intensity Modulated Proton Therapy: A Pilot Study for Nasopharyngeal Carcinoma

Intensity modulated proton therapy (IMPT) with the vertebral artery (VA)-sparing technique has been initially proposed in our institution. This pilot study was conducted to compare the dose to VAs between IMPT and volumetric-modulated arc therapy (VMAT) for patients with nasopharyngeal carcinoma (NPC). A total of six patients with NPC treated by IMPT were enrolled in the study. Target volumes and organs at risk (OARs) were delineated, including 12 samples of right and left VAs, respectively, for each patient. Treatment planning by IMPT and dual-arc VMAT was carried out for comparison. The IMPT plan significantly reduced VA mean dose, V10, V20, V30, V40, and V50, compared to the VMAT plan in all 12 samples (p < 0.001). The average mean dose to VAs for IMPT was 35.2% (23.4–46.9%), which was less compared to VMAT (p < 0.001). Adequate dose coverage was achieved with both IMPT and VMAT plans for three different dose levels of target volumes for all patients. IMPT significantly reduces VA dose while maintaining adequate dose coverage of all target volumes. For patients with head and neck cancer who seek to preserve their blood flow to the brain in order to decrease late vascular and neurologic sequelae, IMPT should be considered. A prospective study with longer follow-up is ongoing to confirm our preliminary results.

Intensity Modulated Proton Beam Therapy versus Volumetric Modulated Arc Therapy for Patients with Nasopharyngeal Cancer: A Propensity Score-Matched Study

(1) Background: We compared the outcomes of patients with nasopharyngeal carcinoma treated with IMPT and VMAT. (2) Methods: We performed a retrospective propensity score matching analysis (1:1) of patients treated with IMPT (years: 2016-2018) and VMAT (2014-2018). Survival was estimated using the Kaplan-Meier method. Multivariate Cox proportional hazards regression analysis was used to identify the independent predictors of survival. Binary toxicity endpoint analyses were performed using a Cox model and logistic regression. (3) Results: Eighty patients who received IMPT and VMAT were included. The median follow-up time was 24.1 months in the IMPT group. Progression-free survival (PFS) and overall survival (OS) were not statistically different between the two groups but potentially better in IMPT group. In multivariate analysis, advanced N-stage and body weight loss (BWL; >7%) during radiotherapy were associated with decreased PFS. The IMPT group had significantly less requirement for nasogastric (NG) tube placement and BWL during treatment. The mean oral cavity dose was the only predictive factor in stepwise regression analysis, and IMPT required a significantly lower mean dose. However, IMPT increased the grade 3 radiation dermatitis. (4) Conclusions: IMPT is associated with reduced rates of NG tube insertion and BWL through reducing oral mean dose, potentially producing better oncologic outcomes.

A Systematic Review of Proton Therapy for the Management of Nasopharyngeal Cancer

Purpose

With improved technology, more patients with nasopharyngeal cancer (NPC) are receiving definitive treatment with proton therapy, which allows greater sparing of dose to normal tissues without compromising efficacy. As there is no randomized data, the purpose of this study was to systematically review the available literature on proton therapy in this setting, focusing on the toxicity endpoints.

Materials and Methods

A systematic search using PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines was conducted in 5 databases: PubMed, Embase, SCOPUS, Web of Science, and the Cochrane Central Register of Controlled Trials. A total of 491 studies were found on the topic of NPC and proton therapy. Following independent study selection by 2 investigators, 9 studies were found to have sufficient focus and relevance to be incorporated into the systematic review.

Results

All 9 studies were retrospective and examined only NPC patients except for one that also included paranasal sinus cancer. One study was a reirradiation study. Four studies used 3D or double scatter technique, while all others used intensity-modulated proton therapy. Oncologic outcomes were similar to intensity-modulated radiation therapy (IMRT) rates, with 2-year local and regional progression-free survival (LRFS) ranging from 84% to 100%, 2-year progression-free survival (PFS) ranging from 75% to 88.9%, and 2-year overall survival (OS) ranging from 88% to 95% in the up-front setting. Four comparison studies with IMRT found significantly lower feeding tube rates (20% versus 65%, P = .015; and 14% versus 85%, P < .001) with proton therapy as well as lower mucositis (G2 46% versus 70%, P = .019; and G3 11% versus 76%, P = .0002). All other acute and late effects were largely improved with proton therapy but not statistically significant.

Conclusions

NPC patients receiving proton therapy maintain good outcomes with improved toxicity profile, likely due to sparing of dose to normal structures. Prospective studies are ongoing to better quantify the magnitude.

Influence of CDK5 Regulatory Subunit-Associated Protein 1-Like 1 Expression on the Survival of Patients with Non-Metastatic Nasopharyngeal Carcinoma

Background

The aim of this study was to investigate the influence of CDK5 regulatory subunit-associated protein 1-like 1 (CDKAL1) expression on the survival of nasopharyngeal carcinoma (NPC) patients.

Methods

A total of 140 non-metastatic NPC patients were retrospectively analyzed. The expression of CDKAL1 was detected by immunohistochemistry.

Results

The CDKAL1-negative group exhibited better overall survival (OS) according to Kaplan–Meier curve analysis (p = 0.006), with 5-year OS rates for the CDKAL1-negative and -positive groups of 89.7% and 70.2%, respectively. The CDKAL1-negative group also exhibited a tendency toward a better progression-free survival (PFS) rate. Multivariate analysis showed that CDKAL1 expression was independently associated with both OS (p = 0.002) and PFS (p = 0.043).

Conclusion

CDKAL1 expression is an independent negative predictor of patient survival in non-metastatic NPC.

A Randomized Controlled Trial Comparing Two Different Schedules for Cisplatin Treatment in Patients with Locoregionally Advanced Nasopharyngeal Cancer

PURPOSE

Previous studies suggest that a cumulative cisplatin dose of 200 mg/m² might be adequate in the intensity-modulated radiation therapy (IMRT) era for locoregionally advanced nasopharyngeal carcinoma (LANPC). However, two cycles of once-every-3-weeks cisplatin at 100 mg/m² has never been prospectively compared with standard once-a-week cisplatin regimen.

PATIENTS AND METHODS

This trial was conducted at three hospitals from 2011 to 2016. Patients who met the eligibility criteria were recruited (ChiCTR-TRC-12001979) and randomly assigned (1:1) via a computer-generated sequence to receive once-every-3-weeks cisplatin at 100 mg/m² for two cycles or once-a-week cisplatin at 40 mg/m² for six cycles concurrently with IMRT. Primary endpoint was failure-free survival and between-group absolute difference of 10% as the noninferiority margin.

RESULTS

A total of 510 patients were enrolled. Median follow-up time was 58.3 months with 85.4% of 3-year failure-free survival in the once-every-3-weeks group and 85.6% in the once-a-week group. An absolute difference of -0.2% (95% confidence interval, -6.3 to 5.9; P _{noninferiority} = 0.0016). Acute toxicities of grade 3 or higher occurred in 55.8% in the once-every-3-weeks group and 66.3% in the once-a-week group (P = 0.015). The most common acute toxicities were hematologic abnormalities, including leukopenia (16% vs. 27%; P = 0.0022) and thrombocytopenia (1% vs. 5%; P = 0.015). The late grade 3-4 auditory loss rate was significantly lower in the once-every-3-weeks group than the once-a-week group (6% vs. 13%; P = 0.0039).

CONCLUSIONS

Once-every-3-weeks cisplatin as concurrent chemoradiotherapy is noninferior to once-a-week cisplatin in the treatment efficacy in the LANPC. Although both regimens are well tolerated, severe acute toxicities and late-onset auditory loss are higher in the once-a-week group.

Toxicity Profiles and Survival Outcomes Among Patients With Nonmetastatic Nasopharyngeal Carcinoma Treated With Intensity-Modulated Proton Therapy vs Intensity-Modulated Radiation Therapy

IMPORTANCE

Patients with nonmetastatic nasopharyngeal carcinoma (NPC) are primarily treated by radiotherapy with curative intent with or without chemotherapy and often experience substantial treatment-related toxic effects even with modern radiation techniques, such as intensity-modulated radiation therapy (IMRT). Intensity-modulated proton therapy (IMPT) may improve the toxicity profile; however, there is a paucity of data given the limited availability of IMPT in regions with endemic NPC.

OBJECTIVE

To compare toxic effects and oncologic outcomes among patients with newly diagnosed nonmetastatic NPC when treated with IMPT vs IMRT with or without chemotherapy.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study included 77 patients with newly diagnosed nonmetastatic NPC who received curative-intent radiotherapy with IMPT or IMRT at a tertiary academic cancer center from January 1, 2016, to December 31, 2019. Forty-eight patients with Epstein-Barr virus (EBV)-positive tumors were included in a 1:1 propensity score-matched analysis for survival outcomes. The end of the follow-up period was March 31, 2021.

EXPOSURES

IMPT vs IMRT with or without chemotherapy.

MAIN OUTCOMES AND MEASURES

The main outcomes were the incidence of acute and chronic treatment-related adverse events (AEs) and oncologic outcomes, including locoregional failure-free survival (LRFS), progression-free survival (PFS), and overall survival (OS).

RESULTS

We identified 77 patients (25 [32.5%] women; 52 [67.5%] men; median [interquartile range] age, 48.7 [42.2-60.3] years), among whom 28 (36.4%) were treated with IMPT and 49 (63.6%) were treated with IMRT. Median (interquartile range) follow-up was 30.3 (17.9-41.5) months. On multivariable logistic regression analyses, IMPT was associated with lower likelihood of developing grade 2 or higher acute AEs compared with IMRT (odds ratio [OR], 0.15; 95% CI, 0.03-0.60; P = .01). Only 1 case (3.8%) of a chronic grade 3 or higher AE occurred in the IMPT group compared with 8 cases (16.3%) in the IMRT group (OR, 0.21; 95% CI, 0.01-1.21; P = .15). Propensity score matching generated a balanced cohort of 48 patients (24 IMPT vs 24 IMRT) and found similar PFS in the IMPT and IMRT groups (2-year PFS, 95.7% [95% CI, 87.7%-100%] vs 76.7% [95% CI, 60.7%-97.0%]; hazard ratio [HR], 0.31; 95% CI, 0.07-1.47; P = .14). No locoregional recurrence or death was observed in the IMPT group from the matched cohort. Two-year LRFS was 100% (95% CI, 100%-100%) in the IMPT group and 86.2% (95% CI, 72.8%-100%) in the IMRT group (P = .08). Three-year OS was 100% (95% CI, 100%-100%) in the IMPT group and 94.1% (95% CI, 83.6%-100%) in the IMRT group (P = .42). Smoking history was the only clinical factor significantly associated with both poor LRFS (HR, 63.37; 95% CI, 3.25-1236.13; P = .006) and poor PFS (HR, 6.33; 95% CI, 1.16-34.57; P = .03) on multivariable analyses.

CONCLUSIONS AND RELEVANCE

In this study, curative-intent radiotherapy with IMPT for nonmetastatic NPC was associated with significantly reduced acute toxicity burden in comparison with IMRT, with rare late complications and excellent oncologic outcomes, including 100% locoregional control at 2 years. Prospective trials are warranted to direct the optimal patient selection for IMPT as the primary radiotherapy modality for nonmetastatic NPC.

Impact of FDG-PET/CT on restaging and response evaluation of locally advanced head and neck cancer patient management

Background:

Head and neck cancer (HNC) accounts for 5% of all new cancer cases and most were locally advanced. Positron emission tomography/computed tomography (PET/CT) in radiotherapy practice in locally advanced head and neck squamous cell carcinoma (HNSCC) is being used in staging and proper contouring. Proper staging is essential for accurate treatment decision.

Methods:

This is a prospective phase II study conducted as a single institute centre to evaluate the role of PET/CT-treatment in staging, contouring and response evaluation of 30 patients with locally advanced HNSCC in contrast to CT scan. Our cases did not undergo radical surgery for the primary tumour, and biopsy was taken with PET/CT post-treatment to evaluate response.

Results:

Median age of patients was 49·4 years (minimum age of 32 years and maximum of 68 years). Males were predominant 22 (73·3%). Nasopharynx was the predominant site 16/30 (53·3%). PET/CT changed the overall staging in 40% of the patients (upstaged in 36·7% and downstaged in 3·3%). Gross tumour volume (GTV) of PET/CT was smaller in 23 patients (76·7%) and larger in 5 (16·7%) than the GTV of conventional CT, whereas GTV of lymph nodes of PET/CT was larger in 20 patients (67·7%) and smaller in 4 (13·3%). PET/CT study detected bone metastasis in two nasopharyngeal carcinoma patients and two cases of 2nd primary tumours which were not detected using conventional CT. The Cox-regression model showed that the median standardised uptake volume (SUV) of the initial tumour had been a dependent predictor of death in patients with HNSCC (p-value = 0·033) where the risk of death was 0·725 times among patients with high SUV of the initial tumour. Consequently, the size of GTV of the tumour was significant in the prediction of death (p = 0·018).

Conclusions:

18F-FDG-PET/CT is useful for staging, radiotherapy delineation as well as aiding proper decision making, in addition to assessment of treatment response in HNSCC patients.

Long non-coding RNAs in nasopharyngeal carcinoma: biological functions and clinical applications

Nasopharyngeal carcinoma (NPC) is one of the most common head and neck malignancies. It has obvious ethnic and regional specificity. Long non-coding RNAs (LncRNAs) are a class of non-protein coding RNA molecules. Emerging research shows that lncRNAs play a key role in tumor development, prognosis, and treatment. With the deepening of sequence analysis, a large number of functional LncRNAs have been found in NPC, which interact with coding genes, miRNAs, and proteins to form a complex regulatory network. However, the specific role and mechanism of abnormally expressed lncRNAs in the pathogenesis of NPC is not fully understood. This article briefly introduced the concept, classification, and functional mechanism of lncRNAs and reviewed their biological functions and their clinical applications in NPC. Specifically, we described lncRNAs related to the occurrence, growth, invasion, metastasis, angiogenesis, and cancer stem cells of NPC; discussed lncRNAs related to Epstein-Barr virus infection; and summarized the role of lncRNAs in NPC treatment resistance. We have also sorted out lncRNAs related to Chinese medicine treatment. We believe that with the deepening of lncRNAs research, tumor-specific lncRNAs may become a new target for the treatment and a biomarker for predicting prognosis.

The influence of facility volume on patient treatments and survival outcomes in nasopharyngeal carcinoma

BACKGROUND

This study evaluates the influence of facility case-volume on nasopharyngeal carcinoma (NPC) treatments and overall survival (OS).

METHODS

The 2004-2015 National Cancer Database was queried for patients with NPC receiving definitive treatment.

RESULTS

A total of 8260 patients (5-year OS: 63.4%) were included. The 1114 unique facilities were categorized into 854 low-volume (treating 1-8 patients), 200 intermediate-volume (treating 9-23 patients), and 60 high-volume (treating 24-187 patients) facilities. Kaplan-Meier log-rank analysis demonstrated significantly improved OS with high-volume facilities (p < 0.001). On cox proportional-hazard multivariate regression after adjusting for age, sex, income, insurance, comorbidity index, histology, AJCC clinical stage, and treatment type, high-volume facilities were associated with lower mortality risk than low-volume (HR = 0.865, p = 0.019) and intermediate-volume facilities (HR = 0.916, p = 0.004). Propensity score matching analysis confirmed this association (p < 0.001).

CONCLUSION

Higher facility volume was an independent predictor of improved OS in NPC, suggesting a possible survival benefit of referrals to high-volume medical centers.

Outcomes of patients with nasopharyngeal carcinoma treated with intensity-modulated radiotherapy

Nasopharyngeal cancer shows a good response to intensity-modulated radiotherapy. However, there is no clear evidence for the benefits of routine use of image-guided radiotherapy. The purpose of this study was to perform a retrospective investigation of the treatment outcomes, treatment-related complications and prognostic factors for nasopharyngeal cancer treated with intensity-modulated radiotherapy and image-guided radiotherapy techniques. Retrospective analysis was performed on 326 consecutive nasopharyngeal cancer patients treated between 2004 and 2015. Potentially significant patient-related and treatment-related variables were analyzed. Radiation-related complications were recorded. The 5-year overall survival and disease-free survival rates of these patients were 77.9% and 70.5%, respectively. Age, AJCC (American Joint Committee on Cancer) stage, retropharyngeal lymphadenopathy, treatment interruption and body mass index were independent prognostic factors for overall survival. Age, AJCC stage, retropharyngeal lymphadenopathy, image-guided radiotherapy and body mass index were independent prognostic factors for disease-free survival. In conclusion, intensity-modulated radiotherapy significantly improves the treatment outcomes of nasopharyngeal cancer. With the aid of image-guided radiotherapy, the advantage of intensity-modulated radiotherapy might be further amplified.

Impact of treatment planning quality assurance software on volumetric-modulated arc therapy plans for prostate cancer patients

INTRODUCTION

Software that evaluates the quality of treatment plans (PlanIQ^TM) has become commercially available in recent years. It includes a feasibility assessment tool that provides the ideal dose volume histogram (DVH) for each organ at risk, based on the ideal dose falloff from the prescribed dose at the target boundary. It is important to investigate whether the PlanIQ^TM assessment tool (Feasibility DVH^TM) can assist treatment planners who have limited to no experience in treatment planning. Therefore, the present study aimed to evaluate this tool's usefulness for improving the quality of treatment plans.

MATERIALS & METHODS

This study included 5 patients with prostate cancer. The treatment planners were 2 graduate students, 2 undergraduate students, and one clinical planner. All students were radiological technology and medical physics students with no clinical experience. Two different volumetric-modulated arc therapy (VMAT) plans were developed before and after Feasibility DVH^TM. The quality of each treatment plan was evaluated based on a scoring system implemented in PlanIQ^TM.

RESULTS

Of 5 patients included, 4 received improved treatment plans when Feasibility DVH^TM was used. Moreover, 4 of 5 treatment planners showed improvement in treatment planning using Feasibility DVH^TM.

CONCLUSIONS

The findings suggest that using the Feasibility DVH^TM tool may improve treatment plans for different planners and patients. However, planners at any level of experience should be trained to check the dose distribution in addition to checking the DVH, which depends on the adequacy of the contours.

Radiation therapy in head and neck cancer

This review summarizes the beginning of radiotherapy, techniques of modern radiation therapy with different types, toxicities induced by radiotherapy and their management. Head and neck radiation therapy is still improving for the better management and control of the cancer and induced radiotherapy toxicities.

Factors Influencing Job Retention and Quality of Life amongst Nasopharyngeal Carcinoma Patients

Objective:

To evaluate the quality of life (QoL) amongst Thai nasopharyngeal cancer patients (NCP) and identify associated factors with QoL.

Methods:

This study was based on secondary data from a cross-sectional study that aimed to develop the Thai version of functional assessment of cancer therapy with nasopharyngeal cancer subscale demographic data, clinical information of participants, and Functional Assessment of Cancer Therapy with Nasopharyngeal cancer subscale (FACT-NP) were utilized. Data were analyzed using Student’s t-test, rank-sum test, variance analysis, and the Kruskal-Wallis test. Multiple linear regression with the stepwise model was used to determine multiple variable analysis. Statistical significance was defined at p-value < 0.05.

Results:

Two hundred and thirty NCP were included in the study with a mean age of 50.3±12.4 years. According to our findings, 68.3% were male, 81.7% were married or living with a partner, and 86.1% were Buddhism had the Eastern Cooperative Oncology Group (ECOG) performance status between 0-2 (95.2 %). The employment status, education level, economic status, ECOG, stage , and disease status significantly influenced patients’ QoL. Patients who had active treatment and received prophylactic percutaneous gastrostomy were also impacted by the FACT-NP score. In the multivariate analysis, employment status, ECOG, and disease status were shown to be significant factors that were associated with their QOL in the final model.

Conclusion:

Employment status was a socioeconomic factor that led to positive QOL amongst NCP.

Lower neck organs at risk sparing in nasopharyngeal carcinoma using hybrid volumetric-modulated arc therapy (hybrid-VMAT): a case report

Introduction:

Nasopharyngeal carcinoma (NPC) is a prevalent disease in Southern China. Radiation therapy remains the primary treatment modality for NPC due to its high radiation sensitivity. Conventional volumetric-modulated arc therapy (VMAT) can achieve excellent target volume coverage and superior conformal dose distributions while sparing organs at risk (OARs). However, VMAT may also produce substantial volume of low-dose region in the surrounding normal tissue. Our oncology centre has incorporated the concept of anterior cervical field with VMAT in clinical practice of NPC treatment planning. The purpose of this treatment-comparison case study is to demonstrate the lower neck OARs sparing ability of hybrid volumetric-modulated arc therapy (hybrid-VMAT) over conventional VMAT for NPC.

Methods:

Four patients diagnosed with NPC of different clinical lymph node staging (N staging) were enrolled for this treatment-comparison case study. Planning target volumes and OARs were delineated with reference to Radiation Therapy Oncology Group (RTOG) 0225/0615. Additional OARs from lower neck region, including thyroid, trachea, cervical spine and pharyngeal constrictor muscles (PCMs), were also delineated. Two treatment techniques, hybrid-VMAT and VMAT, were created for each patient’s dataset.

Results and findings:

Both treatment techniques produced adequate target coverage and reduced radiation dose to the OARs as suggested in RTOG 0225/0615. Hybrid-VMAT plans achieved superior dose reduction in larynx, oesophagus, middle PCM, inferior PCM, cervical spine and trachea comparing with VMAT plans. Hence, the clinical usability and functional outcome of hybrid-VMAT should be further investigated for NPC radiation therapy.

Differences in Radiomics Signatures Between Patients with Early and Advanced T-Stage Nasopharyngeal Carcinoma Facilitate Prognostication

BACKGROUND

Accurately predicting the risk of death, recurrence, and metastasis of patients with nasopharyngeal carcinoma (NPC) is potentially important for personalized diagnosis and treatment. Survival outcomes of patients vary greatly in distinct stages of NPC. Prognostic models of stratified patients may aid in prognostication.

PURPOSE

To explore the prognostic performance of MRI-based radiomics signatures in stratified patients with NPC.

STUDY TYPE

Retrospective.

POPULATION

Seven hundred and seventy-eight patients with NPC (T1-2 stage: 298, T3-4 stage: 480; training cohort: 525, validation cohort: 253).

FIELD STRENGTH/SEQUENCE

Fast-spin echo (FSE) axial T1-weighted images, FSE axial T2-weighted images, contrast-enhanced FSE axial T1-weighted images at 1.5 T or 3.0 T.

ASSESSMENT

Radiomics signatures, clinical nomograms, and radiomics nomograms combining the radiomic score (Radscore) and clinical factors for predicting progression-free survival (PFS) were constructed on T1-2 stage patient cohort (A), T3-4 stage patient cohort (B), and the entire dataset (C).

STATISTICAL TESTS

Least absolute shrinkage and selection operator (LASSO) method was applied for radiomics modeling. Harrell's concordance indices (C-index) were employed to evaluate the predictive power of each model.

RESULTS

Among 4,410 MRI-extracted features, we selected 16, 16, and 14 radiomics features most relevant to PFS for Models A, B, and C, respectively. Only 0, 1, and 4 features were found overlapped between models A/B, A/C, and B/C, respectively. Radiomics signatures constructed on T1-2 stage and T3-4 stage patients yielded C-indices of 0.820 (95% confidence interval [CI]: 0.763-0.877) and 0.726 (0.687-0.765), respectively, which were larger than those on the entire validation cohort (0.675 [0.637-0.713]). Radiomics nomograms combining Radscore and clinical factors achieved significantly better performance than clinical nomograms (P < 0.05 for all).

DATA CONCLUSION

The selected radiomics features and prognostic performance of radiomics signatures differed per the type of NPC patients incorporated into the models. Radiomics models based on pre-stratified tumor stages had better prognostic performance than those on unstratified dataset.

LEVEL OF EVIDENCE

4 Technical Efficacy Stage: 5.

Cochlea sparing optimized radiotherapy for nasopharyngeal carcinoma

BACKGROUND

Definitive chemoradiotherapy (CRT) is standard of care for nasopharyngeal carcinoma. Due to the tumor localization and concomitant platinum-based chemotherapy, hearing impairment is a frequent complication, without defined dose-threshold. In this study, we aimed to achieve the maximum possible cochleae sparing.

MATERIALS AND METHODS

Treatment plans of 20 patients, treated with CRT (6 IMRT and 14 VMAT) based on the QUANTEC organs-at-risk constraints were investigated. The cochleae were re-delineated independently by two radiation oncologists, whereas target volumes and other organs at risk (OARs) were not changed. The initial plans, aiming to a mean cochlea dose < 45 Gy, were re-optimized with VMAT, using 2-2.5 arcs without compromising the dose coverage of the target volume. Mean cochlea dose, PTV coverage, Homogeneity Index, Conformity Index and dose to other OAR were compared to the reference plans. Wilcoxon signed-rank test was used to evaluate differences, a p value < 0.05 was considered significant.

RESULTS

The re-optimized plans achieved a statistically significant lower dose for both cochleae (median dose for left and right 14.97 Gy and 18.47 Gy vs. 24.09 Gy and 26.05 Gy respectively, p < 0.001) compared to the reference plans, without compromising other plan quality parameters. The median NTCP for tinnitus of the most exposed sites was 11.3% (range 3.52-91.1%) for the original plans, compared to 4.60% (range 1.46-90.1%) for the re-optimized plans (p < 0.001). For hearing loss, the median NTCP of the most exposed sites could be improved from 0.03% (range 0-99.0%) to 0.00% (range 0-98.5%, p < 0.001).

CONCLUSIONS

A significantly improved cochlea sparing beyond current QUANTEC constraints is feasible without compromising the PTV dose coverage in nasopharyngeal carcinoma patients treated with VMAT. As there appears to be no threshold for hearing toxicity after CRT, this should be considered for future treatment planning.

Contemporary management of the neck in nasopharyngeal carcinoma

Up to 85% of the patients with nasopharyngeal carcinoma present with regional nodal metastasis. Although excellent nodal control is achieved with radiotherapy, a thorough understanding of the current TNM staging criteria and pattern of nodal spread is essential to optimize target delineation and minimize unnecessary irradiation to adjacent normal tissue. Selective nodal irradiation with sparing of the lower neck and submandibular region according to individual nodal risk is now emerging as the preferred treatment option. There has also been continual refinement in staging classification by incorporating relevant adverse nodal features. As for the uncommon occurrence of recurrent nodal metastasis after radiotherapy, surgery remains the standard of care.

Analysis of prostate intensity- and volumetric-modulated arc radiation therapy planning quality with PlanIQTM

Purpose

The purpose of this study was to assess the quality of treatment planning using the PlanIQ^TM software and to investigate whether it is possible to improve the quality of treatment planning using the “Feasibility dose‐volume histogram (DVH)^TM” implemented in the PlanIQ^TM software.

Methods

Using the PlanIQ^TM software, we retrospectively analyzed the learning curve regarding the quality of the treatment plans for 148 patients of prostate intensity‐modulated radiation therapy and volumetric‐modulated radiation therapy performed at our institution over the past eight years. We also sought to examine the possibility of improving treatment planning quality by re‐planning in 47 patients where the quality of the target dose and the dose limits for organs at risk (OARs) were inadequate. The re‐planning treatment plans referred to the Feasibility DVH^TM implemented in the PlanIQ^TM software and modified the treatment planning system based on the target dose and OAR constraints.

Results

Analysis of the learning curve of the treatment plans quality using PlanIQ^TM software retrospectively showed a trend of improvement in the treatment plan quality from year to year. The improvement in the treatment plans quality was more influenced by dose reduction in the OARs than by target coverage.

In all cases where re‐planning was performed, the improvement in the treatment plan's quality resulted in a better treatment plan than the one adopted for delivery to patients in the clinical plan.

Conclusions

The PlanIQ^TM provided insights into the quality of the treatment plans at our institution and identified problems and areas for improvement in the treatment plans, allowing for the development of appropriate treatment plans for specific patients.

Nongaussian Intravoxel Incoherent Motion Diffusion Weighted and Fast Exchange Regime Dynamic Contrast-Enhanced-MRI of Nasopharyngeal Carcinoma: Preliminary Study for Predicting Locoregional Failure

The aim of the present study was to identify whether the quantitative metrics from pre-treatment (TX) non-Gaussian intravoxel incoherent motion (NGIVIM) diffusion weighted (DW-) and fast exchange regime (FXR) dynamic contrast enhanced (DCE)-MRI can predict patients with locoregional failure (LRF) in nasopharyngeal carcinoma (NPC). Twenty-nine NPC patients underwent pre-TX DW- and DCE-MRI on a 3T MR scanner. DW imaging data from primary tumors were fitted to monoexponential (ADC) and NGIVIM (D, D*, f, and K) models. The metrics Ktrans, ve, and τi were estimated using the FXR model. Cumulative incidence (CI) analysis and Fine-Gray (FG) modeling were performed considering death as a competing risk. Mean ve values were significantly different between patients with and without LRF (p = 0.03). Mean f values showed a trend towards the difference between the groups (p = 0.08). Histograms exhibited inter primary tumor heterogeneity. The CI curves showed significant differences for the dichotomized cutoff value of ADC ≤ 0.68 × 10-3 (mm2/s), D ≤ 0.74 × 10-3 (mm2/s), and f ≤ 0.18 (p < 0.05). τi ≤ 0.89 (s) cutoff value showed borderline significance (p = 0.098). FG's modeling showed a significant difference for the K cutoff value of ≤0.86 (p = 0.034). Results suggest that the role of pre-TX NGIVIM DW- and FXR DCE-MRI-derived metrics for predicting LRF in NPC than alone.

Contralateral Lower Neck Sparing Radiotherapy in Stage N1 Nasopharyngeal Carcinoma: Long-Term Survival Outcomes and Late Toxicities

Purpose

To explore the feasibility of contralateral lower neck sparing radiotherapy for patients with stage N1 nasopharyngeal carcinoma (NPC) by analyzing long-term survival outcomes and late toxicities.

Methods

Data of patients with stage N1 NPC who were treated with contralateral lower neck sparing radiotherapy between January 2013 and December 2015 were analyzed. These patients were all staged by magnetic resonance imaging (MRI), and all received irradiation to the upper neck (levels II, III, and Va) bilaterally along with ipsilateral levels IV and Vb, without irradiation of the contralateral lower neck. Treatment outcomes, regional failure patterns, and late toxicities were examined.

Results

A total of 275 eligible patients with stage N1 NPC were included in the present study. The median follow-up period was 62 months (range, 3-93 months). The 5-year overall survival (OS), distant metastasis-free survival (DMFS), local recurrence-free survival (LRFS), regional recurrence-free survival (RRFS), locoregional recurrence-free survival (LRRFS), and progression-free survival (PFS) rates were 90.5, 91.3, 94.7, 95.3, 91.2, and 81.7%, respectively. A total of 13 patients (4.7%) developed regional recurrence, all of which occurred in the field and not out of the field. Among 254 patients with available data on late toxicities, the most common late toxicity was xerostomia. No late injuries occurred in the carotid arteries, brachial plexus, or spinal cord. In addition to one case (0.4%) of neck fibrosis and three cases (1.2%) of hearing loss, there were no other grade 3-4 late toxicities observed.

Conclusions

Contralateral lower neck sparing radiotherapy would be safe and feasible for patients with stage N1 NPC, with the potential to improve the long-term quality of life of patients.

Loosening Neuro-Optic Structures Dosimetric Constraints Provides High 5-Year Local Recurrence-Free Survival With Acceptable Toxicity in T4 Nasopharyngeal Carcinoma Patients Treated With Intensity-Modulated Radiotherapy

Objective

Whether the original dosimetric constraints of neuro-optic structures (NOS) are appropriate for patients with nasopharyngeal carcinoma (NPC) undergoing intensity-modulated radiotherapy (IMRT) remains controversial. The present study compared the survival rates and radiation-induced optic neuropathy (RION) occurrence between T4 NPC patients whose NOS were irradiated with a near maximum dose received by 2% of the volume (D2%) >55 Gy and ≤55 Gy. Moreover, the NOS dosimetric parameters and their correlation with RION occurrence were also evaluated.

Methods

In this retrospective study, 256 T4 NPC patients treated with IMRT between May 2009 and December 2013 were included. Patient characteristics, survival rates, dosimetric parameters, and RION incidence were compared between the D2% ≤55 Gy and D2% >55 Gy groups.

Results

The median follow-up durations were 87 and 83 months for patients in the D2% >55 Gy and D2% ≤55 Gy groups, respectively. The 5-year local recurrence-free survival rates were 92.0 and 84.0% in the D2% >55 Gy and D2% ≤55 Gy groups (P = 0.043), respectively. There was no significant difference in the 5-year overall survival (OS) between both groups (D2% >55 Gy, 81.6%; D2% ≤55 Gy, 79.4%; P = 0.586). No patients developed severe RION (Grades 3–5), and there was no significant difference (P = 0.958) in the incidence of RION between the two groups. The maximum dose of NOS significantly affected the RION incidence, with a cutoff point of 70.77 Gy.

Conclusion

Appropriately loosening NOS dosimetric constraints in order to ensure a more sufficient dose to the target volume can provide a better 5-year local recurrence-free survival and acceptable neuro-optic toxicity in T4 NPC patients undergoing IMRT.

Split-field versus extended-field step-and-shoot IMRT techniques in nasopharyngeal cancer: a report of acute and late toxicities

Aim:

This study aimed to evaluate acute and late toxicities in nasopharyngeal cancer (NPC) patients who were treated between split-field (SF) and extended-field (EF) step-and-shoot intensity-modulated radiotherapy (IMRT) techniques.

Materials and methods:

Between January 2011 and October 2011, 21 NPC patients with stage I-IVB (7th edition American Joint Committee on Cancer Staging) were randomly assigned to undergo radiotherapy with SF or EF step-and-shoot IMRT technique.

Results:

At a median follow-up time of 60 months (range 3–77), we reported the comparable acute and late toxicities between the two techniques. One patient (9%) in SF-IMRT arm developed grade 3 acute skin toxicity.

Findings:

Both SF and EF step-and-shoot IMRT techniques for NPC patients did not produce any statistically significant differences in both acute and late toxicities. Although no difference in toxicity was observed, technical problems due to field matching management were the obstacles in utilisation of SF-IMRT in our routine practice.

Normal tissue complication probability (NTCP) models for predicting temporal lobe injury after intensity-modulated radiotherapy in nasopharyngeal carcinoma: A large registry-based retrospective study from China

PURPOSE

To develop predictive models with dosimetric and clinical variables for temporal lobe injury (TLI) in nasopharyngeal carcinoma (NPC) after intensity-modulated radiotherapy (IMRT).

MATERIALS AND METHODS

Data of 8194 NPC patients who received IMRT-based treatment were retrospectively reviewed. TLI was diagnosed by magnetic resonance imaging. Dosimetric factors were selected by penalized regression and machine learning, with area under the receiver operating curve (AUC) calculated. Cox proportional hazards models containing the most predictive dosimetric factor with/without clinical variables were performed. A nomogram was generated as a visualization of Cox regression for predicting TLI-free survival.

RESULTS

During median follow-up of 66.8 months (interquartile range [IQR] 54.2-82.2 months), 12.1% of patients (989/8194) developed TLI. Median latency from IMRT to TLI was 36 months (IQR 28-47 months). D_0.5cc (dose delivered to 0.5-cm³ temporal-lobe volume) was the most predictive dosimetric factor (AUC: 0.799). Tolerance dose for 5% and 50% probabilities to develop TLI in 5 years were 65.06 Gy (95% confidence interval [CI]: 64.19-65.92) and 89.75 Gy (95% CI: 87.39-92.11), respectively. A nomogram comprising age, T stage, and D_0.5cc significantly outperformed the model with only D_0.5cc in predicting TLI (C-index: 0.78 vs. 0.737 in train set; 0.775 vs. 0.73 in test set; both P < 0.001). The nomogram-defined high-risk group had worse 5-year TLI-free survival.

CONCLUSIONS

D_0.5cc of 65.06 Gy was the tolerance dose of the temporal lobe. Reducing D_0.5cc decreased risk of TLI, especially in older patients with advanced T stage. The nomogram could predict TLI precisely and allow individualized follow-up management.

Temporal Lobe Necrosis Following Radiotherapy in Nasopharyngeal Carcinoma: New Insight Into the Management

Cerebral radiation necrosis (CRN) is one of the most prominent sequelae following radiation therapy for nasopharyngeal carcinoma (NPC), which might have devastating effects on patients' quality of life (QOL). Advances in histopathology and neuro-radiology have shed light on the management of CRN more comprehensively, yet effective therapeutic interventions are still lacking. CRN was once regarded as progressive and irreversible, however, in the past 20 years, with the application of intensity-modulated radiation therapy (IMRT), both the incidence and severity of CRN have declined. In addition, newly developed medical agents including bevacizumab-a humanized monoclonal antibody against vascular endothelial growth factor (VEGF), nerve growth factor (NGF), monosialotetrahexosylganglioside (GM1), etc., have shown great potency in successfully reversing radiation-induced CRN. As temporal lobes are most frequently compromised in NPC patients, this review will summarize the state-of-the-art progress regarding the incidence, pathophysiology, prevention, treatment, and prognosis of temporal lobe necrosis (TLN) after IMRT in NPC.

Clinical and survival analysis of nasopharyngeal carcinoma with consistently negative Epstein-Barr virus DNA

BACKGROUND

To assess the clinical and survival features of nasopharyngeal carcinoma (NPC) with consistently negative Epstein-Barr virus (EBV) DNA level.

METHODS

Propensity score matching (PSM) method was used to create well-balanced cohorts. Kaplan-Meier method and Cox proportional hazards models were performed to conduct survival analysis.

RESULTS

Four hundred and eighty patients were enrolled. Patients with consistently negative plasma EBV DNA level had a greater chance to present a relatively earlier T and N classification compared with those with positive EBV DNA level (p < .001; p = .015). And patients with consistently negative EBV level were significantly associated with preferable 3-year DFS (95.0% vs. 84.4%, p = .004), DMFS (98.3% vs. 89.4%, p = .009), and OS (100% vs. 97.6%, p = .004).

CONCLUSIONS

NPC patients with consistently negative EBV DNA level performed an earlier clinical stage and negative EBV DNA level was related to preferable survival outcomes.

Cross-Sectional International Survey to Determine the Educational Interests of Spanish-Speaking Latin American Radiation Oncologists

PURPOSE

With the existing oncology disparities in Latin America, physician expertise has been cited as a possible contributor to inferior oncologic outcomes in some cancers. As two-dimensional radiotherapy rapidly evolved to intensity-modulated radiation therapy in Latin America, adequate contouring education is an actionable target to improving physician knowledge and clinical outcomes. Yet, topics of interest to Latin American radiation oncologists are underreported. We assessed Latin American interest in a virtual platform for case discussion and identified the educational topics of most interest to them.

MATERIALS AND METHODS

A Spanish-language online survey was designed by a team of Latin American educators. The questions assessed professional nationality, desire for an online educational platform for case presentation, career length, and topics of interest. Educational topics included head and neck (H&N), CNS, GI, lung, gynecologic, breast, and pediatric cancers, lymphoma, sarcoma, stereotactic body radiotherapy (SBRT), brachytherapy, and medical physics.

RESULTS

One hundred thirty-three surveys were included for analysis. Overall, 127 respondents (98%) affirmed interest in participating in a virtual platform for case discussion and treatment advances. The most popular educational themes were H&N cancers (24%), SBRT (14%), and CNS cancers (13%). Of countries with > 10 respondents, the most popular educational topic remained H&N cancers for Argentina, Chile, and Mexico, but the most popular topic among Peruvian respondents was CNS cancer (27%).

CONCLUSION

With international collaboration and a large sample size, we present the first survey results describing Latin American radiation oncology educational interests. Participants were overwhelmingly interested in a virtual platform, and most were specifically interested in H&N cancer education. These results can be used for focused didactic preparation in Latin America. Future efforts should expand on improving representation and outreach among Central American radiation oncologists.

Chemotherapy in Combination With Radiotherapy for Definitive-Intent Treatment of Stage II-IVA Nasopharyngeal Carcinoma: CSCO and ASCO Guideline

PURPOSE

The aim of this joint guideline is to provide evidence-based recommendations to practicing physicians and other healthcare providers on definitive-intent chemoradiotherapy for patients with stage II-IVA nasopharyngeal carcinoma (NPC).

METHODS

The Chinese Society of Clinical Oncology (CSCO) and ASCO convened an expert panel of radiation oncology, medical oncology, surgery, and advocacy representatives. The literature search included systematic reviews, meta-analyses, and randomized controlled trials published from 1990 through 2020. Outcomes of interest included survival, distant and locoregional disease control, and quality of life. Expert panel members used this evidence and informal consensus to develop evidence-based guideline recommendations.

RESULTS

The literature search identified 108 relevant studies to inform the evidence base for this guideline. Five overarching clinical questions were addressed, which included subquestions on radiotherapy (RT), chemotherapy sequence, and concurrent, induction, and adjuvant chemotherapy options.

RECOMMENDATIONS

Evidence-based recommendations were developed to address aspects of care related to chemotherapy in combination with RT for the definitive-intent treatment of stage II to IVA NPC.Additional information is available at www.asco.org/head-neck-cancer-guidelines.

Modified reduced-volume intensity-modulated radiation therapy in non-metastatic nasopharyngeal carcinoma: A prospective observation series

BACKGROUND AND PURPOSE

Although the efficacy of "reduced-volume intensity-modulated radiation therapy (IMRT)" in nasopharyngeal carcinoma (NPC) has been confirmed, two issues regarding the necessity of clinical target volume 1(CTV1) delineation and the optimal margin of CTV2 remained undetermined. The current series, utilized de-intensification technique that omitted the contouring of CTV1 and narrowed the margin of CTV2 from 10 mm to 8 mm, namely "modified reduced-volume IMRT" was initiated to evaluate the efficacy and feasibility of this renew technique in a prospective series.

PATIENTS AND MATERIALS

Dosimetric analysis was performed in 40 non-metastatic NPC cases to evaluate whether our modification is feasible. Then this de-intensification technique was applied in non-metastatic NPC patients treated in our attending group since late 2014. Survival outcomes focused on local recurrence-free survival (LRFS) and local failure pattern were analyzed.

RESULTS

Preliminary dosimetric evaluation of "modified reduced-volume IMRT" showed that the 60 Gy isodose curve generated naturally by this technique could well wrap the target area of CTV1. Subsequent observation series, which included a total of 471 patients and had a median follow-up time of 46.2 months(range,3.7-70.8 months), reported that 4-year estimated LRFS, regional recurrence-free survival (RRFS), distant metastasis-free survival (DMFS) and overall survival (OS) were 96.6%, 97.7%, 87.7% and 92.4%, respectively. All local recurrence lesions occurred within 95% isodose lines and were considered in-field failures.

CONCLUSIONS

Our de-intensification technique "modified reduced-volume IMRT" was feasible and did not compromise therapeutic efficacy, well-designed multicenter prospective trials are needed for further research.

Treatment Deescalation Strategies for Nasopharyngeal Cancer: A Review

IMPORTANCE

Since the advent of modern radiotherapy techniques and incorporation of systemic chemotherapy for nasopharyngeal cancer, locoregional control has been excellent. However, the rate of treatment-related complications, many of which are irreversible, remains high. New approaches are being explored to determine whether the toxic effects of treatment can be relieved while maintaining disease control. This review presents the current state of deescalation strategies for nasopharyngeal cancer.

OBSERVATIONS

A review of the literature shows that deescalation approaches can be generally categorized into deescalating systemic therapy vs deescalating radiotherapy. This review discusses studies that have explored sparing chemotherapy in selected patients with stage II cancer as well as altering the chemotherapy scheduling, dosing, and agent from the current standard of care, cisplatin. Deescalating radiotherapy has involved decreasing the dose and the treatment volume. In many cases, these approaches are being guided by measuring Epstein-Barr virus DNA levels, which is a robust biomarker for screening, treatment monitoring, and surveillance. Ongoing work with various imaging modalities, such as fluorodeoxyglucose positron emission tomography and dynamic contrast-enhanced or diffusion-weighted magnetic resonance imaging sequences, have shown promise as another biomarker to safely guide practitioners toward deescalation.

CONCLUSIONS AND RELEVANCE

Various strategies to deescalate treatment in nasopharyngeal cancer have been explored, and outcomes have remained excellent in most approaches. Patient selection remains key, and long-term outcomes and late complications are still to be determined. Continued investigation with prospective, multi-institutional studies are needed to better elucidate how treatment for nasopharyngeal carcinoma can best be individualized and deescalated.

Comparative Study of Auto Plan and Manual Plan for Nasopharyngeal Carcinoma Intensity-Modulated Radiation Therapy

Purpose and Objective

Auto planning might reduce the manual time required for the optimization and could also potentially improve the overall plan quality. The aim of this study is to demonstrate the statistical comparison of automatic (AU) and manually (MA) generated nasopharyngeal carcinoma (NPC) intensity-modulated radiation therapy (IMRT) plans.

Materials and Methods

The study included 105 nasopharyngeal carcinoma patients, admitted to our hospital. The patients underwent IMRT treatments. The clinically delivered plans were performed with Eclipse (Version 11.0) using manual optimization. The same plans were optimized successively in Pinnacle^TM3 (version 9.10) treatment planning system using the auto plan software package module. D95 (dose of 95% volume) and D98 (dose of 98% volume) were calculated for the targets and maximum dose (Dmax) and mean dose (Dmean) for the organ at risks (OARs); moreover, the average doses of each target and OARs for 105 patients were evaluated.

Results

There is no significant difference in the homogeneity of the target between AU and MA treatment plans, while a significant difference is observed for what is concerning the OARs or most of OARs in 105 patients, OAR doses were significantly reduced in AU plan. For OARs which have no significant difference between AU and MA plans are highlighted, the mean dose of OARs in AU plans was at least not higher than MA plans.

Conclusion

Nasopharyngeal carcinoma IMRT plans made by an automatic planning tool met the clinical requirements for target prescription dose; moreover, the dose of normal tissues was lower than in MA plans. Clinical physicists' time can be saved and the influence of factors such as the lack of experience in treatment planning can be avoided.

Development of a Nomogram Model for Treatment of Nonmetastatic Nasopharyngeal Carcinoma

IMPORTANCE

Because of tumor heterogeneity, overall survival (OS) differs significantly among individuals with nasopharyngeal carcinoma (NPC), even among those with the same clinical stage. Relying solely on TNM staging to guide treatment remains imperfect.

OBJECTIVES

To establish a comprehensive nomogram to estimate individualized OS and to explore stratified treatment regimens for risk subgroups in nonmetastatic NPC.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study included 8093 patients diagnosed with NPC at a single center in China from April 2009 to December 2015. The sample was split into a training cohort (5398 participants [66.7%]) and validation cohort (2695 [33.3%]). Data were analyzed in May 2020.

EXPOSURES

Age, T stage, N stage, Epstein-Barr virus (EBV) DNA level, serum lactate dehydrogenase (LDH) levels, and albumin (ALB) levels.

MAIN OUTCOMES AND MEASURES

The primary end point was OS. The nomogram for estimating OS was generated based on multivariate Cox proportional hazards regression. The performance of the nomogram was quantified using Harrell concordance index (C index), the area under the curve (AUC) of the receiver operating characteristic curve, and a calibration curve. OS rates were established using the Kaplan-Meier method, and intersubgroup differences were examined by the log-rank test.

RESULTS

Among the 8093 participants, 5688 (70.3%) were men, and the median age at diagnosis was 45 years (range, 7-85 years). Six variables (age, T stage, N stage, EBV DNA levels, LDH levels, and ALB levels) were identified through multivariate Cox regression and incorporated into a nomogram to estimate OS. The resulting nomogram showed excellent discriminative ability and significantly outperformed the eighth edition of the American Joint Committee on Cancer/Union for International Cancer Control TNM staging system for estimating OS (C index, 0.716 [95% CI, 0.698-0.734] vs 0.643 [95% CI, 0.624-0.661]; P < .001; AUC, 0.717 [95% CI, 0.698-0.737] vs 0.643 [95% CI, 0.623-0.662]; P < .001), and the calibration curves showed satisfactory agreement between the actual and nomogram-estimated OS rates. The validation cohort confirmed the results. Patients were stratified into 4 risk groups based on the 25th, 50th, and 75th percentile score values estimated from the nomogram. The 4 nomogram-defined risk groups demonstrated significantly different intergroup OS (3-year OS rates: risk group 1, 1328 of 1345 [98.7%]; risk group 2, 1289 of 1341 [96.1%]; risk group 3, 1222 of 1321 [92.5%]; risk group 4, 1173 of 1391 [84.3%]; P < .001). These risk groups were associated with the efficacy of different treatment regimens. For example, for risk group 4, induction chemotherapy with concurrent chemoradiotherapy was associated with a significantly better OS than concurrent chemoradiotherapy (log-rank P = .008) and intensity-modulated radiotherapy alone (log-rank P < .001).

CONCLUSIONS AND RELEVANCE

In this study, the proposed nomogram model enabled individualized prognostication of OS and could help to guide risk-adapted treatment for patients with nonmetastatic NPC.

Paranasal Sinus Invasion Should Be Classified as T4 Disease in Advanced Nasopharyngeal Carcinoma Patients Receiving Radiotherapy

In this study, we explored the association between paranasal sinus invasion and prognosis in patients with advanced nasopharyngeal carcinoma (NPC, (T3/T4N0–3M0), and we assessed the possibility of considering paranasal sinus invasion a T category in the 8th edition of the American Joint Committee on Cancer staging system. We enrolled 352 NPC patients who received intensity-modulated radiotherapy between 2008 and 2012. Clinical characteristics and follow-up data were collected. The incidence of paranasal sinus invasion was 36.4% (128 of 352 patients). Multivariate cox regression analysis indicated that paranasal sinus invasion and cervical lymphatic metastasis were independent negative prognostic factors for overall survival (OS, P=0.024, P=0.012), progression-free survival (PFS, P=0.007, P=0.007), and distant metastasis-free survival (DMFS, P=0.001, P=0.000). The gross tumor volume of the nasopharynx was an independent negative prognostic factor for OS (P=0.013). Cox regression analysis indicated that there were no significant differences in OS, PFS, DMFS, or local relapse-free survival (LRFS) between NPC patients with T4 stage disease and those with T3 and paranasal sinus invasion (P>0.05). The updated T + N staging system slightly improved the prediction of LRFS (0.649, 95% CI: 0.553–0.745) in NPC patients compared to the AJCC system (0.640, 95% CI: 0.545–0.736; P=0.023). Paranasal sinus invasion is independently associated with a poor prognosis in NPC patients. Thus, we recommend that the AJCC staging system upgrade paranasal sinus invasion to the T4 classification.

The feasibility and efficacy of new SBRT technique HyperArc for recurrent nasopharyngeal carcinoma: noncoplanar cone-based robotic system vs. noncoplanar high-definition MLC based Linac system

The purpose of this study was to evaluate the feasibility and efficacy of HyperArc (HA) for recurrent nasopharyngeal cancer (NPC) by comparing it with the CyberKnife system (CK). Fifteen patients with recurrent nasopharyngeal cancer who were treated using the noncoplanar cone-based robotic CK system were enrolled. CK was delivered with a median dose of 37.5 Gy in 5 fractions. The delivered CK treatment plans were the sources for the corresponding homogeneous HA (HA-H) and inhomogeneous HA (HA-IH) plans. The HA-H plans were generated to meet the corresponding treatment plan criteria for the CK plans. The HA-IH plans were designed to emulate the corresponding inhomogeneous CK isodose distributions. These three SBRT treatment plans were compared with target coverage, sparing of organs at risk (OARs), and dose distribution metrics. The HA-H and HA-IH plans consistently exhibited CTV and PTV coverage levels similar or better to those of the CK plans but significantly reduced the dose to OARs. Using the HA techniques (both HA-H and HA-IH plans), the mean maximal doses to the spinal cord, brainstem, optic nerves, and optic chiasm were reduced by approximately 60%, compared to the CK plans. The high dose spillage, conformity, and homogeneity indices of the HA-H plans were significantly better than those of the CK plans. The HA-IH plans showed faster dose falloff and similar conformity of the HA-H plans and dose heterogeneity of the CK plans. Here we demonstrated the HA treatment plan system for recurrent NPC is feasible, either homogeneous or inhomogeneous delivery. Excellent sparing of OARs and dosimetric distribution and very efficient delivery make HA an attractive SBRT technique for recurrent NPC treatment.

Past, present and future of proton therapy for head and neck cancer

Proton therapy has recently gained substantial momentum worldwide due to improved accessibility to the technology and sustained interests in its advantage of better tissue sparing compared to traditional photon radiation. Proton therapy in head and neck cancer has a unique advantage given the complex anatomy and proximity of targets to vital organs. As head and neck cancer patients are living longer due to epidemiological shifts and advances in treatment options, long-term toxicity from radiation treatment has become a major concern that may be better mitigated by proton therapy. With increased utilization of proton therapy, new proton centers breaking ground, and as excitement about the technology continue to increase, we aim to comprehensively review the evidence of proton therapy in major subsites within the head and neck, hoping to facilitate a greater understanding of the full risks and benefits of proton therapy for head and neck cancer.

EGFR-rich extracellular vesicles derived from highly metastatic nasopharyngeal carcinoma cells accelerate tumour metastasis through PI3K/AKT pathway-suppressed ROS

Nasopharyngeal carcinoma (NPC) is the most common cancer with high metastatic potential that occurs in the epithelial cells of the nasopharynx. Distant metastases are the primary cause for treatment failure and mortality of NPC patients. However, the underlying mechanism responsible for the initiation of tumour cell dissemination and tumour metastasis in NPC is not well understood. Here, we demonstrated that epidermal growth factor receptor (EGFR) was highly expressed in tumour tissues of NPC patients with distant metastases and was associated with a decrease in reactive oxygen species (ROS). We also revealed that extracellular vesicles (EVs) transfer occurred from highly to poorly metastatic NPC cells, mediating cell-cell communication and enhancing the metastatic potential of poorly metastatic NPC cells. Further experiments indicated that EVs derived from highly metastatic NPC cells induced the up-regulation of EGFR and down-regulation of ROS in low metastatic NPC cells. Mechanistically, EGFR-rich EVs-mediated EGFR overexpression down-regulated intracellular ROS levels through the PI3K/AKT pathway, thus promoting the metastatic potential of poorly metastatic NPC cells. Strikingly, treatment with EVs secreted from highly metastatic NPC cells was significantly associated with rapid NPC progression and shorter survival in xenografted mice. These findings not only improve our understanding of EVs-mediated NPC metastatic mechanism but also have important implications for the detection and treatment of NPC patients accompanied by aberrant EGFR-rich EVs transmission.

Optimizing the Treatment Pattern for De Novo Metastatic Nasopharyngeal Carcinoma Patients: A Large-Scale Retrospective Cohort Study

Objectives

To investigate the optimal treatment pattern in patients with de novo metastatic nasopharyngeal carcinoma (NPC).

Methods

We assessed 502 consecutive and unselected de novo metastatic NPC patients in Sun Yat-sen University Cancer Center (SYSUCC) from November 2006 to October 2016 in our study. All patients were treated with palliative chemotherapy (PCT) and 308 patients received locoregional radiotherapy (LRRT) subsequently. Our primary study endpoint was overall survival (OS).

Results

The patients treated with LRRT were associated with improved survival on univariate analysis (3-year OS rate 63.7% vs. 31.8%, P < 0.001) and multivariate analysis (HR 0.52, 95%CI 0.40-0.68, P < 0.001). The overall survival benefit of more than 4 PCT cycles was significant in female (HR 0.45, 95% CI 0.24-0.86, P = 0.016) and patients with multiple metastatic sites (HR 0.42, 95% CI 0.26-0.66, P < 0.001). The application of concurrent chemotherapy (CCT) was not associated with better survival among patients receiving LRRT (HR 1.31, 95% CI 0.92-1.86, P = 0.141).

Conclusion

LRRT prolonged survival in de novo metastatic NPC. For patients treated with multiple metastatic sites, more than 4 cycles of PCT is necessary. CCT does not improve survival in de novo metastatic NPC patients.

Outcome and Optimal Treatment for Esthesioneuroblastoma in the Era of Intensity-Modulated Radiation Therapy: A Single-Center Experience

Purpose

Esthesioneuroblastoma (ENB) is a type of rare malignant neoplasm of the sinonasal cavity. Optimal treatment for ENB is still controversial. A retrospective study was conducted to identify the clinical outcome and optimal treatment for ENB in the era of intensity-modulated radiation therapy (IMRT).

Patients and Methods

Between December 2006 and August 2018, 37 patients with ENB without distant metastasis who underwent neoadjuvant chemotherapy followed by chemoradiotherapy (C+RC) or surgery followed by radiotherapy or chemoradiotherapy (S+R/RC) were retrospectively reviewed at our center.

Results

The median follow-up period was 63.7 months (range, 13.2-111.5 months). Five-year overall survival (OS), progression-free survival (PFS), locoregional relapse-free survival (LRFS), and distant metastasis-free survival (DMFS) were similar between treatment arms (P values > 0.05). With a multivariate analysis, a Karnofsky Performance Status (KPS) of ≤80 was a prognostic factor for poor five-year OS. A KPS of ≤80 and Kadish class C-D tumors were prognostic factors for poor PFS. A KPS of ≤80 was a prognostic factor for poor LRFS. When KPS was ≤80 and tumors were Kadish class C-D, T3-4 and N1 were prognostic factors for poor DMFS. Subgroup analyses also demonstrated that the two treatment arms exhibited similar trends for OS, PFS, LRFS, and DMFS, excluding patients with N1 or Kadish class A-B tumors (P values > 0.05).

Conclusion

In the era of IMRT, S+R/RC failed to improve the outcomes of patients with ENB. C+RC may be a feasible treatment option for patients with ENB.

Optimal induction chemotherapeutic regimen followed by concurrent chemotherapy plus intensity-modulated radiotherapy as first-line therapy for locoregionally advanced nasopharyngeal carcinoma

For patients with locoregionally advanced nasopharyngeal carcinoma (NPC), induction chemotherapy (IC) regimens based on TPF (docetaxel, cisplatin, and 5-fluorouracil), TP (docetaxel and cisplatin), and GP (gemcitabine and cisplatin) have shown excellent survival outcomes as the first-line therapy; however, no trials comparing the efficacy and safety of TPF, TP, and GP have been reported. We report 2 phase II trials comparing the treatment outcomes and side effects of 3 different IC regimens followed by concurrent chemoradiotherapy in locoregionally advanced patients with NPC.A total of 206 locoregionally advanced patients with NPC treated with a combination treatment from January 2012 to January 2014 were enrolled in the 2 studies. The patients received TPF-, TP-, and GP-based IC regimens every 3 weeks, followed by intensity-modulated radiotherapy and concurrent therapy with cisplatin every 3 weeks.After a median follow-up duration of 47 months (10-60 months), the 3-year local recurrence-free survival, regional recurrence-free survival, distant metastases-free survival, progression-free survival, and overall survival rates were 96.4%, 100%, 87.7%, 86%, and 94.7% in the TPF arm; 91.7%, 95.9%, 91.9%, 85.2%, and 92% in the TP arm; 98.6%, 100%, 89.0%, 87.6%, and 89.2% in the GP arm. The survival differences among the 3 arms were not statistically significant (P > .05). The multivariate analysis demonstrated that the IC regimen was not an independent prognostic factor for any survival outcomes. The patients in the TP arm experienced significantly lower grade 3/4 toxicities than the patients in the other 2 arms.TP-based IC regimen has similar efficacy compared with TPF- and GP-based IC regimens; however, TP-based IC regimen has a lower toxicity profile.

Simultaneous Reduction of Volume and Dose in Clinical Target Volume for Nasopharyngeal Cancer Patients

PURPOSE

To compare the treatment outcome and severe late adverse effects (AEs) between conventional volume and dose (CVD) and simultaneously reduced volume and dose (SRVD) of clinical target volume treatments in patients with nasopharyngeal carcinoma.

METHODS AND MATERIALS

This retrospective cohort study enrolled patients with nonmetastatic stage II to IV nasopharyngeal cancer from a single institute. Survival endpoints and severe (≥grade 3) late AEs and comorbidity were compared between groups. The correlation of severe late AEs, comorbidity, and overall survival (OS) were evaluated using Kaplan-Meier and Cox regression methods.

RESULTS

From January 2012 to June 2017, this study enrolled 178 patients, 64 in the CVD group and 114 in the SRVD group. The 2 groups did not differ significantly in patient characteristics except for mean follow-up time (37.6 vs 48.8 months; P = .01). The SRVD group did not significantly differ from the CVD group in local control survival (82.0% vs 78.4%; P = .85), regional control survival (89.9% vs 86.0%; P = .62), or disease-free survival (76.4% vs 66.9%; P = .67). The SRVD group had significantly better OS (93.9% vs 67.0%; P < .001) and salvage survival (79.3% vs 20.7%; P < .01) and a significantly lower ratio of severe lung infection (1 of 113 vs 5 of 59; P = .02). The SRVD group had a significantly lower risk of mortality (hazard ratio [HR], 0.3; P = .03). The factors associated with a significantly higher risk of mortality were N3 (regional lymph node stage status of N3) (HR, 3.0; P = .02); comorbidities of diabetes, coronary artery disease, or chronic kidney disease (grades 2-3) (HR, 3.8; P = .009), and severe lung infection (HR, 6.3; P = .007).

CONCLUSIONS

Simultaneously reduced volume and dose of clinical target volumes did not impair locoregional control or disease-free survival. The benefits of SRVD treatment may include significant reduction in severe late AEs, particularly lung infection, dysphagia, and xerostomia. However, additional studies with longer patient follow-up are required to confirm these benefits.

Gemcitabine and cisplatin versus docetaxel and cisplatin as induction chemotherapy followed by concurrent chemoradiotherapy in locoregionally advanced nasopharyngeal carcinoma from non-endemic area of China

PURPOSE

Although several trials have confirmed the treatment efficacy of induction chemotherapy followed by concurrent chemoradiotherapy (CCRT) in locoregionally advanced nasopharyngeal carcinoma (NPC) from endemic area of China, little is known about the best regime for induction chemotherapy in non-endemic region. This study compared the treatment effect of Gemcitabine and cisplatin (GP) versus docetaxel and cisplatin (TP) followed by concurrent chemoradiotherapy in locoregionally advanced NPC from non-endemic area of China.

MATERIALS AND METHODS

A total of 196 locoregionally advanced NPC patients were enrolled in this study, with 142 and 54 patients in TP and GP followed by concurrent chemoradiotherapy groups. The primary endpoint was treatment response of induction chemotherapy. The secondary endpoints included disease-free survival. The Kaplan-Meier method was used to evaluate the efficacy between treatment groups.

RESULTS

The median follow-up time was 45.5 months (range: 6-60.5 months). During induction chemotherapy course, GP contributed higher treatment response rate than TP (68.1% vs. 47.1%, p = 0.007). Patients in GP group had better DFS and LRFS than those in TP group (3-year and 5-year DFS, 86.8% and 82.5% vs. 71.7% and 68%, p = 0.036; 3-year and 5-year LRFS, 96.2% and 96.2% vs. 90.5% and 82.8%, p = 0.03). No significant difference of adverse events was observed between two treatment groups in the whole course.

CONCLUSION

This study suggested that GP followed by CCRT was better than TP followed by CCRT in improving survival outcomes of locoregionally advanced NPC patients from non-endemic area of China.

Toxicity and dosimetric analysis of nasopharyngeal carcinoma patients undergoing radiotherapy with IMRT or VMAT: A regional center's experience

OBJECTIVES

To observe the differences of dosimetric parameters and late toxicities in Nasopharyngeal Carcinoma (NPC) patients treated with intensity-modulated radiotherapy (IMRT) or volumetric modulated arc therapy (VMAT), which may provide the selective basis about radiation technology in clinical practices.

METHODS AND MATERIALS

Dosimetric parameters and late toxicities were collected and retrospectively analyzed from 627 NPC patients (stage as I-IVA/IVB) between January 2010 and December 2015.

RESULTS

The median D2 of all targets and D50 of PGTVnd (regional lymph nodes) were lower in VAMT than those in IMRT, while the median D95 and D98 of PGTVnx (primary lesions) were higher in VMAT than those in IMRT (p < 0.05). Superior sparing of the organs at risk were observed in VMAT. The maximum dose of the brainstem, spinal cord, temporal lobes, temporomandibular joint, optic chiasm, and lens were lower in VMAT than those in IMRT, where the median dose reduction ranged from 0.56 to 3.56 Gy (p < 0.05). Meanwhile, the median parotid glands V30 in VMAT was reduced by approximately 2% compared to that in IMRT (p = 0.027). Regarding the late toxicities, ototoxicity, trismus, and temporal lobe injury were reduced by VMAT (p < 0.05). Furthermore, the late toxicities were correlative with the radiation dose of the corresponding OARs (p < 0.05).

CONCLUSION

For NPC treatment plans, the VMAT might provide not only more favorable dose distributions of targets but also better sparing of normal tissue than observed in IMRT. Furthermore, VMAT possibly provides less treatment-related late toxicities such as ototoxicity, trismus, and temporal lobe injury.

Adding Concurrent Chemotherapy to Intensity-Modulated Radiotherapy Does Not Improve Treatment Outcomes for Stage II Nasopharyngeal Carcinoma: A Phase 2 Multicenter Clinical Trial

Purpose: To explore the efficacy of concomitant chemotherapy in intensity-modulated radiotherapy (IMRT) to treat stage II nasopharyngeal carcinoma (NPC). Methods and Materials: In this randomized phase 2 study [registered with ClinicalTrials.gov (NCT01187238)], eligible patients with stage II (2010 UICC/AJCC) NPC were randomly assigned to either IMRT alone (RT group) or IMRT combined with concurrent cisplatin (40 mg/m², weekly) (CCRT group). The primary endpoint was overall survival (OS). The second endpoints included local failure-free survival (LFFS), regional failure-free survival (RFFS), disease-free survival (DFS), distant metastasis-free survival (DMFS), and acute toxicities. Results: Between May 2010 to July 2012, 84 patients who met the criteria were randomized to the RT group (n = 43) or the CCRT group (n = 41). The median follow-up time was 75 months. The OS, LFFS, RFFS, DFS, and DMFS for the RT group and CCRT group were 100% vs. 94.0% (p = 0.25), 93.0% vs. 89.3% (p = 0.79), 97.7% vs. 95.1% (p = 0.54), 90.4% vs. 86.6% (p = 0.72), and 95.2% vs. 94.5% (p = 0.77), respectively. A total of 14 patients experienced disease failure, 7 patients in each group. The incidence of grade 2 to 4 leukopenia was higher in the CCRT group (p = 0.022). No significant differences in liver, renal, skin, or mucosal toxicity was observed between the two groups. Conclusion: For patients with stage II NPC, concomitant chemotherapy with IMRT did not improve survival or disease control but had a detrimental effect on bone marrow function.

Emerging radiotherapy technologies and trends in nasopharyngeal cancer

Technology has always driven advances in radiotherapy treatment. In this review, we describe the main technological advances in radiotherapy over the past decades for the treatment of nasopharyngeal cancer (NPC) and highlight some of the pressing issues and challenges that remain. We aim to identify emerging trends in radiation medicine. These include advances in personalized medicine and advanced imaging modalities, standardization of planning and delineation, assessment of treatment response and adaptive re‐planning, impact of particle therapy, and role of artificial intelligence or automation in clinical care. In conclusion, we expect significant improvement in the therapeutic ratio of radiotherapy treatment for NPC over the next decade.

An optimal posttreatment surveillance strategy for cancer survivors based on an individualized risk-based approach

The optimal post-treatment surveillance strategy that can detect early recurrence of a cancer within limited visits remains unexplored. Here we adopt nasopharyngeal carcinoma as the study model to establish an approach to surveillance that balances the effectiveness of disease detection versus costs. A total of 7,043 newly-diagnosed patients are grouped according to a clinic-molecular risk grouping system. We use a random survival forest model to simulate the monthly probability of disease recurrence, and thereby establish risk-based surveillance arrangements that can maximize the efficacy of recurrence detection per visit. Markov decision-analytic models further validate that the risk-based surveillance outperforms the control strategies and is the most cost-effective. These results are confirmed in an external validation cohort. Finally, we recommend the risk-based surveillance arrangement which requires 10, 11, 13 and 14 visits for group I to IV. Our surveillance strategies might pave the way for individualized and economic surveillance for cancer survivors.

m6A Reader YTHDC2 Promotes Radiotherapy Resistance of Nasopharyngeal Carcinoma via Activating IGF1R/AKT/S6 Signaling Axis

N6-methyladenosine (m⁶A) modification has been reported as a critical regulator of gene transcript expression. Although m⁶A modification plays important roles in tumor development, its role in therapeutic resistance remains unknown. In this study, we aimed to examine the expression level of m⁶A-modification related proteins and elucidate the effect of m⁶A-related proteins on radiation response in nasopharyngeal carcinoma (NPC). Among the genes that participated in m⁶A modification, YTHDC2, a m⁶A reader, was found to be consistently highly expressed in radioresistant NPC cells. Knocking down of YTHDC2 expression in radioresistant NPC cells improved the therapeutic effect of radiotherapy in vitro and in vivo, whereas overexpression of YTHDC2 in radiosensitive NPC cells exerted an opposite effect. Bioinformatics and mechanistic studies revealed that YTHDC2 could physically bound to insulin-like growth factor 1 receptor (IGF1R) messenger RNA and promoted translation initiation of IGF1R mRNA, which in turn activated the IGF1R-AKT/S6 signaling pathway. Thus, the present study suggests that YTHDC2 promotes radiotherapy resistance of NPC cells by activating the IGF1R/ATK/S6 signaling axis and may serve as a potential therapeutic target in radiosensitization of NPC cells.

Label-free quantitative mass spectrometry from formalin-fixed paraffin-embedded samples of nasopharyngeal carcinoma: Preliminary results from a non-endemic European cohort of patients

Aim

Report our results of biomarker discovery in formalin-fixed paraffin-embedded (FFPE) nasopharyngeal carcinoma (NPC) via proteomic analysis.

Background

Nasopharyngeal carcinoma (NPC) is a rare cancer in Western countries. Proteomic analysis have already been reported as a useful tool to provide biomarkers. Formalin-fixed paraffin-embedded (FFPE) samples, despite largely underused, can provide invaluable information for biomarker research via proteomic analysis.

Methods

FFPE samples of NPC were submitted to protein extraction followed by FASP-digestion and label-free quantitative mass spectrometry (MS). Patients' received concurrent chemoradiation with or without adjuvant chemotherapy as per Intergroup 0099 trial. IMRT was delivered following the RTOG0615 specifications. Toxicity was scored using the CTCAE 4.03 tables. Survival was estimated using Kaplan-Meier curves. Log-rank was used to detect differences. KEGG ontology graphics were generated.

Results

28 FFPE samples from NPC patients were used. Patients were: 79% male, 97% Caucasians, 86% WHO type 3, 40% T1, 10% T2, 25% T3, and 25% T4. With a median follow up of 37 months, local control was 83 (T1, 100% T2, T3 and T4), overall survival was 84%, and six patients developed distant metastases. All five patients that died were due to metastatic disease. Tumor samples contained a median of 75% of tumor material. We found Epstein-Barr (EBV) and Herpes simplex (HSV) viruses' related proteins significantly present in early-stage primary NPC (T1 and T2, p < 0.01). A pool of 10 proteins was statistically up-regulated in the metastatic group of patients (p < 0.01). Median survival from this M1 group was <1 year (p < 0.001).

Conclusions

FFPE samples yielded adequate material for MS analysis. We found EBV and HSV related proteins on early-stage NPC, and proteomic profiling associated with distant metastases, potential candidates of disease biomarkers. Validation is needed.

Two-year outcome of concurrent chemoradiation with carboplatin with or without adjuvant carboplatin/fluorouracil in nasopharyngeal cancer: A multicenter randomized trial

BACKGROUND

According to the noninferiority result of chemoradiation with carboplatin in our previous nasopharyngeal carcinoma (NPC) study along with the inconclusive data on the efficacy of adjuvant chemotherapy (AC) following concurrent chemoradiotherapy (CCRT), we designed to assess the role of adjuvant carboplatin/fluorouracil following CCRT with carboplatin in locoregionally advanced NPC.

MATERIALS AND METHODS

A multicenter randomized trial was conducted at 5 cancer centers in Thailand. We enrolled in stage T2N0M0-T4N2M0 (American Joint Cancer Committee 7th edition) WHO Type 2 NPC patients. N3 or metastatic disease patients were excluded. Participants were randomized into 2 groups: CCRT plus AC group vs the CCRT alone group. Patients in both groups received weekly carboplatin 100 mg/m² for 6 cycles concurrently with radiotherapy 69.96-70 Gy. Patients in the AC group subsequently received 3 cycles of carboplatin area under curve-5 plus 1000 mg/m²/day of fluorouracil infusion within 96 hours every 3 weeks. We report the 2-year overall survival (OS), disease-free survival (DFS), loco-regional recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS). Treatment-related toxicities and compliance were also explored.

RESULTS

Of 175 patients, 82 (46.9%) were assigned to the AC group, and 93 (53.1%) to the CCRT group. The compliance rate during CCRT was 90% and 86% in the AC and CCRT group, whereas 81.7% during adjuvant treatment in the AC group. With a median follow-up time of 24.4 months (interquartile range 17.9-24.4), the 2-year OS rate was 89.6% in the AC group and 81.8% in the CCRT group (P= 0.167). The 2-year DFS rate was 86.8% in the AC group and 74.6% in the CCRT group (P = 0.042). The 2-year LRFS rate was 91.5% in the AC group and 88.2% in the CCRT group (P = 0.443). The 2-year DMFS rate was 85.4% in the AC group and 79.6% in the CCRT group (P = 0.294). The most frequent serious (grade 3/4) nonhematologic toxicity was acute mucositis, which occurred 5% in the AC group vs 4% in the CCRT group (P = 0.498). For hematologic toxicity, grade 3-4 leukopenia were found 10% and 5% in the adjuvant and CCRT groups, respectively (P = 0.003). Multivariate analyses determined stage N2 disease was an adverse prognostic factor associated with shorter OS, DFS, and DMFS. And the adjuvant treatment was a significant protective factor for only DFS.

CONCLUSIONS

The addition of adjuvant carboplatin/fluorouracil following CCRT with carboplatin significantly improved 2-year DFS in stage T2N0M0-T4N2M0 NPC albeit there was a nonsignificant trend in favor of a higher 2-year OS, LRFS, and DMFS. Long-term efficacy and late toxicities of AC still require exploration.

A Prospective 10-Year Observational Study of Reduction of Radiation Therapy Clinical Target Volume and Dose in Early-Stage Nasopharyngeal Carcinoma

PURPOSE

Current guideline recommends a uniform method of delineation of subclinical disease within the primary clinical target volume (CTVp) for all stages of nasopharyngeal carcinoma (NPC). We performed a prospective observational study to investigate the outcomes with a reduced CTVp and radiation dose for early-stage NPC.

METHODS AND MATERIALS

Patients with newly diagnosed, biopsy-proven World Health Organization type II-III and American Joint Committee on Cancer/Union for International Cancer Control sixth edition stage T1-2N0-1 disease were enrolled. All patients were treated with intensity modulated radiation therapy alone. We categorized CTVp into CTVp1 (high risk) and CTVp2 (low risk). CTVp1 comprised of gross tumor (on magnetic resonance imaging or contrast-enhanced computed tomography) plus a 5-mm margin (3-mm posteriorly) and was prescribed to 60 Gy in 30 fractions (fr). CTVp2 was generated from CTVp1 plus a 5-mm margin (3 mm posteriorly), excluding the maxillary and cavernous sinuses, and was prescribed to 54 Gy in 30 fr. The prescribed doses to the primary and nodal gross tumor volume (GTVp and GTVn) were 68 Gy in 30 fr and 60 to 66 Gy in 30 fr, respectively. Primary endpoint was local recurrence-free survival. This study was registered in ClinicalTrials.gov, number NCT03839602.

RESULTS

From May 2001 to August 2006, 103 patients were recruited and completed IMRT. With a median follow-up of 15.2 years (range, 2.1-18.1 years), only 1 patient had local failure. Ten-year local recurrence-free survival, regional recurrence-free survival, distant metastasis-free survival, and overall survival were 90.3%, 88.3%, 90.3%, and 91.2%, respectively. Among late IMRT-related adverse events, we recorded 2 patients with G1 cranial nerve injury, 3 patients with G3 hearing loss, and 3 patients with G3 subcutaneous fibrosis. No patients had temporal lobe necrosis, brain stem injury, or trismus.

CONCLUSIONS

Decreased CTV margins and radiation doses can achieve long-term tumor control with mild late toxicities for patients with early-stage NPC.