International recommendations for plasma Epstein-Barr virus DNA measurement in nasopharyngeal carcinoma in resource-constrained settings: lessons from the COVID-19 pandemic.

The effects of the COVID-19 pandemic continue to constrain health-care staff and resources worldwide, despite the availability of effective vaccines. Aerosol-generating procedures such as endoscopy, a common investigation tool for nasopharyngeal carcinoma, are recognised as a likely cause of SARS-CoV-2 spread in hospitals. Plasma Epstein-Barr virus (EBV) DNA is considered the most accurate biomarker for the routine management of nasopharyngeal carcinoma. A consensus statement on whether plasma EBV DNA can minimise the need for or replace aerosol-generating procedures, imaging methods, and face-to-face consultations in managing nasopharyngeal carcinoma is urgently needed amid the current pandemic and potentially for future highly contagious airborne diseases or natural disasters. We completed a modified Delphi consensus process of three rounds with 33 international experts in otorhinolaryngology or head and neck surgery, radiation oncology, medical oncology, and clinical oncology with vast experience in managing nasopharyngeal carcinoma, representing 51 international professional societies and national clinical trial groups. These consensus recommendations aim to enhance consistency in clinical practice, reduce ambiguity in delivering care, and offer advice for clinicians worldwide who work in endemic and non-endemic regions of nasopharyngeal carcinoma, in the context of COVID-19 and other airborne pandemics, and in future unexpected settings of severe resource constraints and insufficiency of personal protective equipment.

Genomic insights into the peopling of the Southwest Pacific.

The appearance of people associated with the Lapita culture in the South Pacific around 3,000 years ago marked the beginning of the last major human dispersal to unpopulated lands. However, the relationship of these pioneers to the long-established Papuan people of the New Guinea region is unclear. Here we present genome-wide ancient DNA data from three individuals from Vanuatu (about 3,100-2,700 years before present) and one from Tonga (about 2,700-2,300 years before present), and analyse them with data from 778 present-day East Asians and Oceanians. Today, indigenous people of the South Pacific harbour a mixture of ancestry from Papuans and a population of East Asian origin that no longer exists in unmixed form, but is a match to the ancient individuals. Most analyses have interpreted the minimum of twenty-five per cent Papuan ancestry in the region today as evidence that the first humans to reach Remote Oceania, including Polynesia, were derived from population mixtures near New Guinea, before their further expansion into Remote Oceania. However, our finding that the ancient individuals had little to no Papuan ancestry implies that later human population movements spread Papuan ancestry through the South Pacific after the first peopling of the islands.

Deep Learning for Automated Contouring of Primary Tumor Volumes by MRI for Nasopharyngeal Carcinoma.

Background Nasopharyngeal carcinoma (NPC) may be cured with radiation therapy. Tumor proximity to critical structures demands accuracy in tumor delineation to avoid toxicities from radiation therapy; however, tumor target contouring for head and neck radiation therapy is labor intensive and highly variable among radiation oncologists. Purpose To construct and validate an artificial intelligence (AI) contouring tool to automate primary gross tumor volume (GTV) contouring in patients with NPC. Materials and Methods In this retrospective study, MRI data sets covering the nasopharynx from 1021 patients (median age, 47 years; 751 male, 270 female) with NPC between September 2016 and September 2017 were collected and divided into training, validation, and testing cohorts of 715, 103, and 203 patients, respectively. GTV contours were delineated for 1021 patients and were defined by consensus of two experts. A three-dimensional convolutional neural network was applied to 818 training and validation MRI data sets to construct the AI tool, which was tested in 203 independent MRI data sets. Next, the AI tool was compared against eight qualified radiation oncologists in a multicenter evaluation by using a random sample of 20 test MRI examinations. The Wilcoxon matched-pairs signed rank test was used to compare the difference of Dice similarity coefficient (DSC) of pre- versus post-AI assistance. Results The AI-generated contours demonstrated a high level of accuracy when compared with ground truth contours at testing in 203 patients (DSC, 0.79; 2.0-mm difference in average surface distance). In multicenter evaluation, AI assistance improved contouring accuracy (five of eight oncologists had a higher median DSC after AI assistance; average median DSC, 0.74 vs 0.78; P < .001), reduced intra- and interobserver variation (by 36.4% and 54.5%, respectively), and reduced contouring time (by 39.4%). Conclusion The AI contouring tool improved primary gross tumor contouring accuracy of nasopharyngeal carcinoma, which could have a positive impact on tumor control and patient survival. © RSNA, 2019 Online supplemental material is available for this article. See also the editorial by Chang in this issue.

Nasopharyngeal carcinoma.

Epidemiological trends during the past decade suggest that although incidence of nasopharyngeal carcinoma is gradually declining, even in endemic regions, mortality from the disease has fallen substantially. This finding is probably a result of a combination of lifestyle modification, population screening coupled with better imaging, advances in radiotherapy, and effective systemic agents. In particular, intensity-modulated radiotherapy has driven the improvement in tumour control and reduction in toxic effects in survivors. Clinical use of Epstein-Barr virus (EBV) as a surrogate biomarker in nasopharyngeal carcinoma continues to increase, with quantitative assessment of circulating EBV DNA used for population screening, prognostication, and disease surveillance. Randomised trials are investigating the role of EBV DNA in stratification of patients for treatment intensification and deintensification. Among the exciting developments in nasopharyngeal carcinoma, vascular endothelial growth factor inhibition and novel immunotherapies targeted at immune checkpoint and EBV-specific tumour antigens offer promising alternatives to patients with metastatic disease.

Longitudinal post-radiotherapy plasma Epstein-Barr virus DNA trends inform on optimal risk stratification in endemic nasopharyngeal carcinoma.

OBJECTIVES: To characterize longitudinal changes in Epstein-Barr virus (EBV) DNA post-radiotherapy in nasopharyngeal carcinoma (NPC) patients, and investigate whether an early (0-2 weeks) or delayed (8-12 weeks) EBV DNA result better predicts for disease-free survival (DFS). MATERIALS AND METHODS: Histologically-confirmed NPC patients with ≥1 EBV DNA test quantified using the harmonized BamHI-W polymerase chain reaction-based assay at 0-2 and 8-12 weeks post-radiotherapy were included. RESULTS: We identified 302 patients with EBV DNA measured at 0-2 weeks post-radiotherapy; of which, 110 (36.4 %) underwent a repeat test at 8-12 weeks post-treatment. Patients harboring a detectable EBV DNA at 0-2 weeks experienced an inferior DFS (adjusted HR1-264 copies 1.72 [95 %CI: 1.05-2.83], P = 0.031; AHR≥265 copies 4.39 [95 %CI: 1.68-11.44], P = 0.002 relative to 0 copies/mL). At 8-12 weeks, we observed substantial shifts in EBV DNA readings from 0 to 2 weeks; 76/110 (69.1 %) and 34/110 (30.9 %) patients at 0-2 weeks versus 90/110 (81.8 %) and 20/110 (18.2 %) at 8-12 weeks recorded undetectable and detectable EBV DNA, respectively. Positive EBV DNA at 8-12 weeks was strongly associated with relapse (73.3 % [11/15] for 1-264; 80.0 % [4/5] for ≥265 subgroups had relapses versus 15.6 % [14/90] for 0 copies/mL). Area under receiver operating curve values for 2-year relapse rates were 0.817 (95 %CI: 0.725-0.909) for stage + EBV DNA8-12w versus 0.654 (95 %CI: 0.542-0.765) for stage + EBV DNA0-2w. CONCLUSION: EBV DNA is dynamic post-radiotherapy, and delayed EBV DNA testing better enriched for higher-risk NPC patients. This implicates trials investigating adjuvant chemotherapy intensification based on early EBV DNA testing.

The impact of the COVID-19 pandemic on nasopharyngeal carcinoma patients - a national cancer centre experience.

Purpose or objective: The COVID-19 pandemic has resulted in significant healthcare implications, with care for cancer patients compromised due to resource diversion towards battling the pandemic. We aim to investigate the impact of the peak wave of the pandemic in 2020 on the delivery of cancer care in Singapore, specifically via our nasopharyngeal carcinoma (NPC) treatment data. This study applies real world numbers to the impact of COVID-19 on cancer care delivery in Singapore. The choice of nasopharyngeal cancer allows a good direct estimate of common treatment measures such as time to biopsy, time to staging scans, time to treatment commencement, due to its clear protocol and algorithms for staging and treatment; thus serving as an excellent surrogate for the effectiveness and timeliness of the different aspects of cancer care delivery. Materials and methods: In this retrospective study, we included all patients with newly diagnosed NPC from 1st January to 31st May from 2017 to 2020 at our centre. This time period was chosen as it coincided with the period in 2020 during the COVID-19 pandemic where there was the most strain on healthcare resources and the most restrictions on population movement within Singapore, which may impact on healthcare seeking behaviour. Narrowing down the time period to the first 5 months of the 4 respective years also allowed us to reduce the effect of annual seasonal variation in patient numbers seen as a result of holidays and festive periods such as the Lunar New Year and scheduled school holidays. Electronic medical records (EMR) were accessed. Only newly diagnosed NPC cases were included in our analysis. Patients with second synchronous primary malignancies or NPC disease recurrence were excluded. Data analysis was carried out using a combination of SPSS and Microsoft Excel. Results: Significantly, there was a reduction of 37-46.3% in newly diagnosed NPC cases during the peak of the COVID-19 pandemic from January to end May 2020 compared to the preceding three years. Despite the reduction in numbers of newly diagnosed NPC, there was no statistically significant differences in delay from biopsy to the first radiation oncology visit and from biopsy to the first day of treatment in 2020 compared to the preceding years. All the patients treated in our centre also received the standard NPC treatment for their disease stage as per international guidelines. Conclusion: We recommend a heightened awareness of the dangers of delaying cancer presentation and care in healthcare policies and resource allocation and at the same time, encourage patient's confidence in their ability to seek care. With the resurgence of new COVID-19 variants and case numbers worldwide and in Singapore, this study focuses upon the need to be aware of the exigencies of other clinical groups in resource utilization. It would be instructive to compare this study with future long term follow up to investigate the trajectory of our cancer care delivery, as well as survival outcomes.

Efficacy and safety of apatinib in recurrent/metastatic nasopharyngeal carcinoma: A pilot study.

BACKGROUND: There is no standard-of-care for recurrent, metastatic nasopharyngeal carcinoma (rmNPC) after first-line chemotherapy. Here, we report the efficacy and safety data of apatinib in rmNPC patients. METHODS: Thirty-five biopsy-proven rmNPC patients received apatinib at 500 mg/day under a compassionate access programme. Primary end-point was objective response rate (ORR; RECIST v1.1). Kaplan-meier method was used to estimate progression-free survival (PFS) and overall survival (OS). Toxicity was assessed by CTCAE v4.0. RESULTS: 82.9% (29 of 35) of patients had poly-metastatic rmNPC. All patients, except five, were platinum-refractory; 37.1% (13 of 35) received ≥ 2 lines. Median number of apatinib cycles was 4.0 (IQR: 2.0-8.0). ORR was 31.4% (11 of 35 [95% CI: 16.9-49.3]) and disease control rate was 74.3% (26 of 35 [95% CI: 56.7-87.5]); 11 (31.4%) and 4 (11.4%) patients demonstrated response for ≥ 6 and ≥ 12 months, respectively. Median PFS and OS was 3.9 (95% CI: 3.1-5.5) months and 5.8 (95% CI: 4.5-8.0) months, respectively. Among the ≥ 12-month responders, all patients had pre-apatinib EBV DNA titer of <700 (range: 353-622) copies/ml; this was consistent with the association of PFS with pre-apatinib EBV DNA titer (adjusted HR 3.364 [95% CI: 1.428-7.923] for ≥ 4000 copies/ml, P = 0.006). 42.9% (15 of 35) of patients required dose reduction. Nonetheless, only five (14.3%) patients suffered from G3 toxicities (two haematological, one hypertension, one hand-foot syndrome and one elevated aminotransferases). CONCLUSION: Our data suggests potential efficacy of apatinib in rmNPC patients. Although incidence of severe toxicities was low, dose modification was required in 42.9% of patients.

International Recommendations on Reirradiation by Intensity Modulated Radiation Therapy for Locally Recurrent Nasopharyngeal Carcinoma.

PURPOSE: Reirradiation for locally recurrent nasopharyngeal carcinoma (NPC) is challenging because prior radiation dose delivered in the first course is often close to the tolerance limit of surrounding normal structures. A delicate balance between achieving local salvage and minimizing treatment toxicities is needed. However, high-level evidence is lacking because available reports are mostly retrospective studies on small series of patients. Pragmatic consensus guidelines, based on an extensive literature search and the pooling of opinions by leading specialists, will provide a useful reference to assist decision-making for these difficult decisions. METHODS AND MATERIALS: A thorough review of available literature on recurrent NPC was conducted. A set of questions and preliminary draft guideline was circulated to a panel of international specialists with extensive experience in this field for voting on controversial areas and comments. A refined second proposal, based on a summary of the initial voting and different opinions expressed, was recirculated to the whole panel for review and reconsideration. The current guideline was based on majority voting after repeated iteration for final agreement. RESULTS: The initial round of questions showed variations in clinical practice even among the specialists, reflecting the lack of high-quality supporting data and the difficulties in formulating clinical decisions. Through exchange of comments and iterative revisions, recommendations with high-to-moderate agreement were formulated on general treatment strategies and details of reirradiation (including patient selection, targets contouring, dose prescription, and constraints). CONCLUSION: This paper provides useful reference on radical salvage treatment strategies for recurrent NPC and optimization of reirradiation through review of published evidence and consensus building. However, the final decision by the attending clinician must include full consideration of an individual patient's condition, understanding of the delicate balance between risk and benefits, and acceptance of risk of complications.

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.

Management of the neck after chemoradiotherapy for head and neck cancers in Asia: consensus statement from the Asian Oncology Summit 2009.

The addition of a planned neck dissection after radiotherapy has traditionally been considered standard of care for patients with positive neck-nodal disease. With the acceptance of chemoradiotherapy as the new primary treatment for patients with locally advanced squamous-cell head and neck cancers, and the increasing numbers of patients who achieve a complete response, the role of planned neck dissection is now being questioned. The accuracy and availability of a physical examination or of different imaging modalities to identify true complete responses adds controversy to this issue. This consensus statement will address some of the controversies surrounding the role of neck dissection following chemoradiotherapy for squamous-cell carcinomas of the head and neck, with particular reference to patients in Asia.

Lactate dehydrogenase kinetics predict chemotherapy response in recurrent metastatic nasopharyngeal carcinoma.

BACKGROUND: Lactate dehydrogenase (LDH) is a known prognostic biomarker for the endemic variant of nasopharyngeal carcinoma (NPC). Here, we investigate whether serial changes in LDH level between chemotherapy (CT) cycles are associated with tumour response to CT. METHODS: Patients with biopsy-proven, recurrent or treatment-naïve metastatic NPC (mNPC) were recruited. All patients had received at least two cycles of platinum-based doublet or triplet CT, with serial assessment of LDH prior to every cycle of chemotherapy (CT1-6). Patients harbouring conditions that affect LDH levels (IU/L) were excluded. Tumour response was assessed after every two cycles of CT by RECIST v1.1. RESULTS: A total of 158 patients were analysed, including 77 with recurrent and 81 with treatment-naïve mNPC. High pre-CT LDH was associated with an inferior overall survival [hazard ratio 1.93 for ⩾240 versus <240 (1.34-2.77), p < 0.001], which is consistent with published literature. We found that both absolute LDH levels and LDH ratios (LDHCTn: LDHCTn-1) were associated with tumour response [partial response versus progressive disease: median value across CT1-6 = 168-190 versus 222-398 (absolute); 0.738-0.988 versus 1.039-1.406 (ratio)], albeit LDH ratio had a tighter variance between patients. Finally, we showed that an LDH ratio cut-off of 1.0 at CT1, CT3 and CT5 was predictive of progressive disease at CT2, CT4, CT6 [area under the curve of 0.73 (0.65-0.80)]. CONCLUSION: Herein, we characterised the longitudinal variation of LDH in response to CT in mNPC. Our findings suggest the potential utility of interval LDH ratio to predict subsequent tumour response to CT.

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.

High-Dimensional Characterization of the Systemic Immune Landscape Informs on Synergism Between Radiation Therapy and Immune Checkpoint Blockade.

PURPOSE: Improved antitumor responses have been observed in patients after combination radiation therapy (RT) and immune checkpoint blockade (ICB). Whether these clinical responses are linked to the host systemic immune system has not been elucidated. METHODS AND MATERIALS: In this single-institution prospective observational study, peripheral blood was longitudinally collected from 10 patients with metastatic disease who had responded to anti-PD-1/anti-PD-L1 ICB and received RT (8-50 Gy in 1-5 fractions) upon disease progression at the following timepoints: baseline (pre-RT), 1 to 2 weeks post-RT, and post-ICB (cycle 1) on reintroduction post-RT. To thoroughly characterize the interaction between combined RT-ICB and the host immune system, we performed high-dimensional, mass cytometry-based immunophenotyping of circulating lymphocytes using a 40-marker panel addressing lineage, differentiation, activation, trafficking, cytotoxicity, and costimulatory and inhibitory functions. Phenotypic expression of circulating lymphocytes was compared across patients and time points and correlated with post-RT tumor responses. RESULTS: Foremost, we demonstrated excellent posttreatment clinical responses, including 4 local responses with >50% reduction in radiated tumor size, 1 out-of-field response, and 4 patients who resumed ICB for >1 year. Baseline and post-RT immune states were highly heterogeneous among patients. Despite this interindividual heterogeneity in baseline immune states, we observed a systemic immune reaction to RT-ICB common across patients, histology, and radiation sites; a subset of pre-existing Ki-67+ CD8+ T cells were increased post-RT and further expanded upon reintroduction of ICB post-RT (2.3-fold increase, P = .02). Importantly, RT did not alter the phenotypic profile of these Ki-67+ CD8+ T cells, which was characterized by a distinct activated and differentiated effector phenotype. CONCLUSIONS: Collectively, these findings point toward a sustained reinvigoration of host antitumor immunity after RT-ICB and suggest an expansion in activated Ki-67+ CD8+ T cells as a possible demonstration of this synergy, thereby providing new insights that may support the development of optimal sequencing strategies.

International Guideline on Dose Prioritization and Acceptance Criteria in Radiation Therapy Planning for Nasopharyngeal Carcinoma.

PURPOSE: The treatment of nasopharyngeal carcinoma requires high radiation doses. The balance of the risks of local recurrence owing to inadequate tumor coverage versus the potential damage to the adjacent organs at risk (OARs) is of critical importance. With advancements in technology, high target conformality is possible. Nonetheless, to achieve the best possible dose distribution, optimal setting of dose targets and dose prioritization for tumor volumes and various OARs is fundamental. Radiation doses should always be guided by the As Low As Reasonably Practicable principle. There are marked variations in practice. This study aimed to develop a guideline to serve as a global practical reference. METHODS AND MATERIALS: A literature search on dose tolerances and normal-tissue complications after treatment for nasopharyngeal carcinoma was conducted. In addition, published guidelines and protocols on dose prioritization and constraints were reviewed. A text document and preliminary set of variants was circulated to a panel of international experts with publications or extensive experience in the field. An anonymized voting process was conducted to rank the proposed variants. A summary of the initial voting and different opinions expressed by members were then recirculated to the whole panel for review and reconsideration. Based on the comments of the panel, a refined second proposal was recirculated to the same panel. The current guideline was based on majority voting after repeated iteration for final agreement. RESULTS: Variation in opinion among international experts was repeatedly iterated to develop a guideline describing appropriate dose prioritization and constraints. The percentage of final agreement on the recommended parameters and alternative views is shown. The rationale for the recommendations and the limitations of current evidence are discussed. CONCLUSIONS: Through this comprehensive review of available evidence and interactive exchange of vast experience by international experts, a guideline was developed to provide a practical reference for setting dose prioritization and acceptance criteria for tumor volumes and OARs. The final decision on the treatment prescription should be based on the individual clinical situation and the patient's acceptance of optimal balance of risk.

Intensity-modulated radiotherapy for paranasal sinuses and base of skull tumors.

Paranasal sinus and skull base tumors are rare aggressive head and neck cancers, and typically present in the locally advanced stages. As a result, achieving wide surgical resection with clear margins is a challenge for these tumors, and radiotherapy is thus usually indicated as an adjuvant modality following surgery to optimize local control. Given the integral role of radiotherapy in the management of this subgroup of head and neck tumors, the advent of intensity-modulated radiotherapy (IMRT) has led to substantial improvement of clinical outcomes for these patients. This is primarily driven by the improvement in radiation dosimetry with IMRT compared to conventional two dimensional (2D)- and 3D-techniques, in terms of ensuring dose intensity to the tumor target coupled with minimizing dose exposure to critical organs. Consequently, the evident clinical benefits of IMRT have been in reduction of normal tissue toxicities, ranging from critical neurological symptoms to less debilitating but bothersome symptoms of eye infections and radiation-induced skin changes. Another domain where IMRT has potential clinical utility is in the management of a subset of non-resectable T4 paranasal sinus and skull base tumors. For these inoperable lesions, the steep dose-gradient between tumor and normal tissue is even more advantageous, given the crucial need to maintain dose intensity to the tumor. Innovative strategies in this space also include the use of induction chemotherapy for patient selection. In this review, we summarized the data for the aforementioned topics, including specific discussions on the different histologic subtypes of paranasal sinus and skull base tumors.

Combinatorial strategies of radiotherapy and immunotherapy in nasopharyngeal carcinoma.

Immunotherapy and radiation therapy (RT) have each demonstrated clinical success in the treatment of nasopharyngeal carcinoma (NPC) when utilized independently. Several characteristics of NPC make it particularly well suited for immunotherapeutic strategies, such as the association with viral infections like EBV and human papilloma virus (HPV), upregulation of PD-L1 expression, and the high number of tumor infiltrating lymphocytes. Immune checkpoint blockade is one such immunotherapeutic strategy that is gaining popularity rapidly. However, clinical benefit of immunotherapy using immune checkpoint inhibitors has been limited to only a small subset of patients with existing T cell responses. Additionally, they are frequently associated with dose-limiting immune-related toxicities. On the other hand, RT is a conventional strategy for NPC treatment, which has demonstrated high efficacy in local tumor control and has also been reported to exhibit immune modulatory effects. However, the abscopal effect of RT alone, i.e., the regression of distant metastases outside of the irradiation field, remains a rare phenomenon. Furthermore, RT treatment efficacy is also limited by radioresistance and radiation-related toxicities. Hence, the combination of RT and immunotherapy has the potential to improve treatment efficacy over either individual therapies alone. Here, we reviewed the clinical problem in locally advanced and recurrent/metastatic NPC, and discussed how combinatorial RT and immunotherapeutic strategies can be relevant to NPC treatment in each clinical scenario by examining the underlying mechanisms involved in the different strategies.

Characteristics of Radiotherapy Trials Compared With Other Oncological Clinical Trials in the Past 10 Years.

Importance: Modern precision radiotherapy is an innovative and effective treatment of cancer, yet it is unclear how radiotherapy trials are affected by expanding targeted and immune therapies and declining National Institutes of Health funding. Objective: To analyze and compare the characteristics of radiotherapy trials with other oncological trials registered on ClinicalTrials.gov. Design, Setting, and Participants: This is a cross-sectional analysis of trials registered on ClinicalTrials.gov between June 1, 2007, and May 8, 2017. Records of all 243 758 clinical studies registered by May 8, 2017, were downloaded, but only 25 907 interventional oncological trials registered between June 1, 2007, and May 8, 2017, and whose primary purpose was "treatment" were included in the final analysis. Trials were categorized according to cancer type and other registration information. Main Outcomes and Measures: Characteristics of radiotherapy trials were compared with characteristics of other oncological trials. Chronological shifts in radiotherapy trials were also analyzed. Results: Of the 25 907 trials selected, 1378 (5.3%) were radiotherapy trials and 24 529 (94.7%) were other oncological studies. The number of radiotherapy trials increased gradually from 94 (June 1, 2007, through May 31, 2008) to 192 (June 1, 2015, through May 31, 2016). Radiotherapy trials were less likely than other oncological studies to be registered before participant enrollment (763 of 1370 [55.7%] vs 16 105 of 24 434 [65.9%]; P < .001), to be blinded (45 of 1378 [3.3%] vs 2784 of 24 529 [11.3%]; P < .001), or to involve multiple geographic regions (2.4% vs 9.5%; P < .001), but they were more likely to be phase 2 to 3 (773 of 1124 [68.8%] vs 12 910 of 22 300 [57.9%]; P < .001) and to have a data-monitoring committee (839 of 1264 [66.4%] vs 11 728 of 21 060 [55.7%]; P < .001). Only a minority of radiotherapy trials were industry sponsored, which was significantly lower than for other oncological trials (80 of 1378 [5.8%] vs 10 651 of 24 529 [43.4%]; P < .001; adjusted odds ratio, 0.08; 95% CI, 0.06-0.10). The number of National Institutes of Health-sponsored radiotherapy trials decreased from 80 of 544 trials (14.7%) from 2007 to 2012 to 72 of 834 trials (8.6%) from 2012 to 2017 (P < .001). Radiotherapy trials with a sample size of more than 100 patients decreased from 155 of 543 trials (28.5%) from 2007 to 2012 to 157 of 833 trials (18.8%) from 2012 to 2017 (P < .001). Conclusions and Relevance: The limited number of and the scarcity of funding for radiotherapy trials is concerning given the integral role of radiotherapy in the clinical management of patients with cancer worldwide. A multidisciplinary collaboration to promote and fund more radiotherapy research is warranted.

Prognostic Model for Stratification of Radioresistant Nasopharynx Carcinoma to Curative Salvage Radiotherapy.

Purpose To investigate for a prognostic index (PI) to personalize recommendations for salvage intensity-modulated radiotherapy (IMRT) in patients with locally recurrent nasopharyngeal carcinoma (lrNPC). Methods Patients with lrNPC from two academic institutions (Sun Yat-Sen University Cancer Center [SYSUCC-A; n = 251 (training cohort)] and National Cancer Centre Singapore [NCCS; n = 114] and SYSUCC-B [n = 193 (validation cohorts)]) underwent salvage treatment with IMRT from 2001 to 2015. Primary and secondary clinical end points were overall survival (OS) and grade 5 toxicity-free rate (G5-TFR), respectively. Covariate inclusion to the PIs was qualified by a multivariable two-sided P < .05. Discrimination and calibration of the PIs were assessed. Results The primary PI comprised covariates that were adversely associated with OS in the training cohort (gross tumor volumerecurrence hazard ratio [HR], 1.01/mL increase [ P < .001], agerecurrence HR, 1.02/year increase [ P = .008]; repeat IMRT equivalent dose in 2-Gy fractions [EQD2] ≥ 68 Gy HR, 1.42 [ P = .03]; prior radiotherapy-induced grade ≥ 3 toxicities HR, 1.90 [ P = .001]; recurrent tumor [rT]-category 3 to 4 HR, 1.96 [ P = .005]), in ascending order of weight. Discrimination of the PI for OS was comparable between training and both validation cohorts (Harrell's C = 0.71 [SYSUCC-A], 0.72 [NCCS], and 0.69 [SYSUCC-B]); discretization by using a fixed PI score cutoff of 252 determined from the training data set yielded low- and high-risk subgroups with disparate OS in the validation cohorts (NCCS HR, 3.09 [95% CI, 1.95 to 4.89]; SYSUCC-B HR, 3.80 [95% CI, 2.55 to 5.66]). Our five-factor PI predicted OS and G5-TFR (predicted v observed 36-month OS and G5-TFR, 22% v 15% and 38% v 44% for high-risk NCCS and 26% v 31% and 45% v 46% for high-risk SYSUCC-B). Conclusion We present a validated PI for robust clinical stratification of radioresistant NPC. Low-risk patients represent ideal candidates for curative repeat IMRT, whereas novel clinical trials are needed in the unfavorable high-risk subgroup.

International guideline for the delineation of the clinical target volumes (CTV) for nasopharyngeal carcinoma.

PURPOSE: Target delineation in nasopharyngeal carcinoma (NPC) often proves challenging because of the notoriously narrow therapeutic margin. High doses are needed to achieve optimal levels of tumour control, and dosimetric inadequacy remains one of the most important independent factors affecting treatment outcome. METHOD: A review of the available literature addressing the natural behaviour of NPC and correlation between clinical and pathological aspects of the disease was conducted. Existing international guidelines as well as published protocols specified by clinical trials on contouring of clinical target volumes (CTV) were compared. This information was then summarized into a preliminary draft guideline which was then circulated to international experts in the field for exchange of opinions and subsequent voting on areas with the greatest controversies. RESULTS: Common areas of uncertainty and variation in practices among experts experienced in radiation therapy for NPC were elucidated. Iterative revisions were made based on extensive discussion and final voting on controversial areas by the expert panel, to formulate the recommendations on contouring of CTV based on optimal geometric expansion and anatomical editing for those structures with substantial risk of microscopic infiltration. CONCLUSION: Through this comprehensive review of available evidence and best practices at major institutions, as well as interactive exchange of vast experience by international experts, this set of consensus guidelines has been developed to provide a practical reference for appropriate contouring to ensure optimal target coverage. However, the final decision on the treatment volumes should be based on full consideration of individual patients' factors and facilities of an individual centre (including the quality of imaging methods and the precision of treatment delivery).

The most important questions in cancer research and clinical oncology : Question 1. Could the vertical transmission of human papilloma virus (HPV) infection account for the cause, characteristics, and epidemiology of HPV-positive oropharyngeal carcinoma, non-smoking East Asian female lung adenocarcinoma, and/or East Asian triple-negative breast carcinoma?

Specific research foci: (1) Mouse models of gamma-herpes virus-68 (γHV-68) and polyomavirus (PyV) infections during neonatal versus adult life. (2) For human papilloma virus (HPV)-positive oropharyngeal carcinoma (OPC)-(a) Asking the question: Is oral sex a powerful carcinogen? (b) Examining the evidence for the vertical transmission of HPV infection. (c) Examining the relationship between HPV and Epstein-Barr virus (EBV) infections and nasopharyngeal cancer (NPC) in West European, East European, and East Asian countries. (d) Examining the association between HPV-positive OPC and human leukocyte antigen (HLA). (3) For non-smoking East Asian female lung adenocarcinoma-(a) Examining the incidence trends of HPV-positive OPC and female lung adenocarcinoma according to birth cohorts. (b) Examining the association between female lung adenocarcinoma and HPV. (c) Examining the associations of lung adenocarcinoma with immune modulating factors. (4) For triple-negative breast carcinoma (TNBC) in East Asians-(a) Examining the association between TNBC and HPV. (b) Examining the unique epidemiological characteristics of patients with TNBC. A summary "epidemiological" model tying some of these findings together.