Accuracy of whole-body FDG-PET and FDG-PET/CT in M staging of nasopharyngeal carcinoma: a systematic review and meta-analysis

Neural Network-based Automated Classification of 18F-FDG PET/CT Lesions and Prognosis Prediction in Nasopharyngeal Carcinoma Without Distant Metastasis

PURPOSE

To evaluate the diagnostic performance of the PET Assisted Reporting System (PARS) in nasopharyngeal carcinoma (NPC) patients without distant metastasis, and to investigate the prognostic significance of the metabolic parameters.

PATIENTS AND METHODS

Eighty-three NPC patients who underwent pretreatment 18F-FDG PET/CT were retrospectively collected. First, the sensitivity, specificity, and accuracy of PARS for diagnosing malignant lesions were calculated, using histopathology as the gold standard. Next, metabolic parameters of the primary tumor were derived using both PARS and manual segmentation. The differences and consistency between the 2 methods were analyzed. Finally, the prognostic value of PET metabolic parameters was evaluated. Prognostic analysis of progression-free survival (PFS) and overall survival (OS) was conducted.

RESULTS

PARS demonstrated high patient-based accuracy (97.2%), sensitivity (88.9%), and specificity (97.4%), and 96.7%, 84.0%, and 96.9% based on lesions. Manual segmentation yielded higher metabolic tumor volume (MTV) and total lesion glycolysis (TLG) than PARS. Metabolic parameters from both methods were highly correlated and consistent. ROC analysis showed metabolic parameters exhibited differences in prognostic prediction, but generally performed well in predicting 3-year PFS and OS overall. MTV and age were independent prognostic factors; Cox proportional-hazards models incorporating them showed significant predictive improvements when combined. Kaplan-Meier analysis confirmed better prognosis in the low-risk group based on combined indicators (χ² = 42.25, P < 0.001; χ² = 20.44, P < 0.001).

CONCLUSIONS

Preliminary validation of PARS in NPC patients without distant metastasis shows high diagnostic sensitivity and accuracy for lesion identification and classification, and metabolic parameters correlate well with manual. MTV reflects prognosis, and its combination with age enhances prognostic prediction and risk stratification.

Personalised PET imaging in oncology: an umbrella review of meta-analyses to guide the appropriate radiopharmaceutical choice and indication

PURPOSE

For several years, oncological positron emission tomography (PET) has developed beyond 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG). This umbrella review of meta-analyses aims to provide up-to-date, comprehensive, high-level evidence to support appropriate referral for a specific radiopharmaceutical PET/computed tomography (CT) or PET/magnetic resonance (MR) in the diagnosis and staging of solid cancers other than brain malignancies.

METHODS

We performed a systematic literature search on the PubMed/MEDLINE and EMBASE databases for meta-analyses assessing the accuracy of PET/CT and/or PET/MRI with [18F]FDG, somatostatin- receptor-targeting 68Ga-DOTA-peptides, 18F-labelled dihydroxyphenylalanine ([18F]DOPA), prostate-specific membrane antigen (PSMA)-targeted radioligands, and fibroblast activation protein inhibitors (FAPI) in the diagnosis/disease characterisation and staging of solid cancers other than brain tumours.

RESULTS

The literature search yielded 449 scientific articles. After screening titles and abstracts and applying inclusion and exclusion criteria, we selected 173 meta-analyses to assess the strength of evidence. One article was selected from references. Sixty-four meta-analyses were finally considered. The current evidence corroborates the role of [18F]FDG as the main player in molecular imaging; PSMA tracers are useful in staging and re-staging prostate cancer; somatostatin-targeting peptides (e.g. [68Ga]Ga- DOTA-TOC and -TATE) or [18F]DOPA are valuable in neuroendocrine tumours (NETs). FAPI has emerged in gastric cancer assessment. According to search and selection criteria, no satisfactory meta-analysis was selected for the diagnosis/detection of oesophageal cancer, the diagnosis/detection and N staging of small cell lung cancer and hepatic cell carcinoma, the diagnosis/detection and M staging of melanoma and Merkel cell carcinoma, cervical, vulvar and penis cancers, the N and M staging of lung and gastroenteropancreatic NET, testicular cancer, and chondrosarcoma, and the M staging of differentiated thyroid, bladder and anal cancers.

CONCLUSION

The comprehensive high-level evidence synthesised in the present umbrella review serves as a guiding compass for clinicians and imagers, aiding them in navigating the increasingly intricate seascape of PET examinations.

Real World Presentation and Treatment Outcomes with a Predominant Induction Chemotherapy Based Approach in Nasopharyngeal Carcinoma: A Sixteen Year Report from a Teaching Hospital in India

INTRODUCTION

Nasopharyngeal carcinoma (NPC) is a rare malignancy in India except in north-eastern states. We present our institutional experience of 16 years highlighting management, outcomes, responses and toxicities.

MATERIALS AND METHODS

NPC patients registered at our center during the period of 2000-2015. The primary objective of the study was to assess the overall survival (OS). Secondary outcome included determinations of response rates, progression free survival (PFS) and to assess treatment-related toxicity (CTCAE v4.0). Institute ethics committee approval was obtained prior to initiation of this study.

RESULTS

Data was retrieved from complete records of 222 patients out of 390 registered during study period. There were 163 males (73.4%) and 59 females (26.6%) with a male to female ratio of 2.8:1. The median age was 35 years (range 6-73). Only 5.6% (n = 12) presented in early-stage disease (stage I and II) while 89.6% (n = 199) were advanced stage (stage III, IVA, IVB). Five patients (2.2%) presented as metastatic disease. Majority of patients were treated with induction chemotherapy followed by concurrent chemoradiation (CCRT) {76.1%, n = 169}. Relapses were documented in 10.4% patients. 5% patients had loco-regional relapse while distant metastases were seen in 4% patients. The 3-year PFS and OS rates are 60.9% and 68.4%, respectively. Achieving a CR predicted superior OS on multivariate analysis.

CONCLUSIONS

NPC is a rare malignancy and majority presented with advanced stages. This data outlines our experience and outcomes with a predominantly induction chemotherapy followed by definitive CCRT based approach.

Survival effect of pretreatment FDG-PET-CT on nasopharyngeal cancer

BACKGROUND/PURPOSE

Accurate staging is the first step for optimal treatment selection in patients with nasopharyngeal carcinoma (NPC). In this propensity-score-matched, population-based cohort study, we investigated the survival effects of pretreatment 8-fluorodeoxyglucose positron emission tomography-computed tomography (¹⁸FDG-PET-CT) on patients with NPC.

METHODS

We included patients with stage I-IVA NPC receiving radiotherapy or concurrent chemoradiotherapy and categorized them into two 1:1 propensity score-matched groups according to whether or not they underwent pretreatment ¹⁸FDG-PET-CT and compared their outcomes.

RESULTS

Of the 10,756 patients, propensity score matching yielded 4366 patients in each group. According to multivariable Cox regression analyses, the most prominent correlation between pretreatment ¹⁸FDG-PET-CT and all-cause death was observed in patients with stage II NPC (adjusted hazard ratio [aHR], 0.77; 95% confidence interval [CI], 0.60-0.90; P = .0433), followed by patients with stage III NPC (aHR, 0.81; 95% CI, 0.69-0.94; P = .0071) and patients with stage IVA NPC (aHR, 0.88; 95% CI, 0.79-0.97; P = .0091). This association was not significant in patients with stage I NPC (aHR, 1.20; 95% CI, 0.75-1.93; P = .4426).

CONCLUSION

Pretreatment ¹⁸FDG-PET-CT is associated with longer survival in patients with clinical stage II-IVA NPC but not in stage I NPC.

Determining the suitability of definitive radiation therapy in patients with metastatic nasopharyngeal carcinoma based on PET/CT: a large cohort study

OBJECTIVES

To determine patients with de novo metastatic nasopharyngeal carcinoma (mNPC) who would benefit from receiving definitive radiation therapy (DRT) along with their pre-existing palliative chemotherapy (PCT) by evaluating their post-PCT Deauville scores and EBV DNA.

METHODS

A total of 570 mNPC patients, treated with PCT or PCT+DRT, were studied. EBV DNA levels, along with post-PCT Deauville scores, were used to stratify risk based on the recursive partitioning analysis (RPA).

RESULTS

Significant differences were observed in the survival rates of patients with Deauville scores of 1-3 and 4-5 (2-year progression-free survival (PFS): 23.4% versus 8.5%, p < 0.001; 2-year overall survival (OS): 56.8% versus 18.8%, p < 0.001). RPA yielded three distinct groups in the increasing order of risk (Deauville scores of all RPA I-II were within the range of 1-3): (1) RPA I: EBV DNA levels at a pretreatment concentration ≤ 4000 copies/mL and undetectable post-PCT; (2) RPA II: EBV DNA levels either at a pretreatment concentration > 4000 copies/mL or at a pretreatment concentration ≤ 4000 copies/mL and detectable post-PCT; (3) RPA III: Deauville scores 4-5. While patients in RPA I and RPA II had significantly PFS rates when treated with PCT+DRT than when treated with PCT alone (RPA I: 72.7% versus 13.4%, RPA II: 37.8% versus 6.3%), those in RPA III did not experience such PFS benefits (6.5% versus 9.7%).

CONCLUSION

PCT+DRT might improve the survival rates in mNPC patients in the low- and mid-risk strata but not those of patients in the high-risk strata.

KEY POINTS

We use the Deauville scores and the concentrations of the Epstein-Barr virus (EBV) DNA to determine those patients with de novo metastatic NPC who would benefit from radiation therapy.

The role of PET/CT in radiotherapy for nasopharyngeal carcinoma

Radiotherapy has already been developed as the standard of care for patients with nasopharyngeal carcinoma (NPC), and precision staging, target volume delineation, prognosis prediction, and post-treatment surveillance are essential in the management of NPC. Positron emission tomography/computed tomography (PET/CT) is increasingly recognized as an imaging modality to guide precision radiotherapy in these areas. The feasibility and efficacy of 18F-FDG PET/CT have been confirmed in tumor diagnosis, treatment planning, prognosis, surveillance, and assessment. Coupled with the capability of revealing tumor metabolic information, 18F-FDG PET/CT is more accurate in identifying primary lesions and metastases of NPC than other conventional imaging methods including CT and MRI and shows the independently diagnostic and prognostic value for radiotherapy. However, 18F-FDG has limitations due to its physiological distribution in brain tissue and increasing uptake in post-radiation inflammation. Novel PET radiotracers including FAPI, NaF, CHO, and FLT are explored as alternatives with potential superiority for radiotherapy in NPC. In this review, we summarized the evolving role of PET/CT in the management of radiotherapy in NPC patients, aiming to facilitate precision radiotherapy from a molecular imaging aspect.

PET-CT in Clinical Adult Oncology-V. Head and Neck and Neuro Oncology

Simple Summary

Positron emission tomography (PET), typically combined with computed tomography (CT) has become a critical advanced imaging technique in oncology. With PET-CT, a radioactive molecule (radiotracer) is injected in the bloodstream and localizes to sites of tumor because of specific cellular features of the tumor that accumulate the targeting radiotracer. The CT scan, performed at the same time, provides information to facilitate attenuation correction, so that radioactivity from deep or dense structures can be better visualized, but with head and neck malignancies it is critical to provide correlating detailed anatomic imaging. PET-CT has a variety of applications in oncology, including staging, therapeutic response assessment, restaging, and surveillance. This series of six review articles provides an overview of the value, applications, and imaging and interpretive strategies of PET-CT in the more common adult malignancies. The fifth report in this series provides a review of PET-CT imaging in head and neck and neuro oncology.

Abstract

PET-CT is an advanced imaging modality with many oncologic applications, including staging, assessment of response to therapy, restaging, and longitudinal surveillance for recurrence. The goal of this series of six review articles is to provide practical information to providers and imaging professionals regarding the best use of PET-CT for specific oncologic indications, and the potential pitfalls and nuances that characterize these applications. In addition, key tumor-specific clinical information and representative PET-CT images are provided to outline the role that PET-CT plays in the management of oncology patients. Hundreds of different types of tumors exist, both pediatric and adult. A discussion of the role of FDG PET for all of these is beyond the scope of this review. Rather, this series of articles focuses on the most common adult malignancies that may be encountered in clinical practice. It also focuses on FDA-approved and clinically available radiopharmaceuticals, rather than research tracers or those requiring a local cyclotron. The fifth review article in this series focuses on PET-CT imaging in head and neck tumors, as well as brain tumors. Common normal variants, key anatomic features, and benign mimics of these tumors are reviewed. The goal of this review article is to provide the imaging professional with guidance in the interpretation of PET-CT for the more common head and neck malignancies and neuro oncology, and to inform the referring providers so that they can have realistic expectations of the value and limitations of PET-CT for the specific type of tumor being addressed.

Correlation between 18F-FDG PET/CT and diffusion-weighted MRI parameters in head and neck squamous cell carcinoma at baseline and after chemo-radiotherapy. A retrospective single institutional study

OBJECTIVES

The relationship between glucose metabolism and tumor cellularity before chemo-radiotherapy in patients with head and neck squamous cell carcinoma (SCC) has never been compared with that of patients evaluated after treatment. This retrospective study analyzed the correlation between glucose metabolism parameters expressed by standardized uptake value (SUV) derived from 18F-fluorodeoxyglucose (18F-FDG) PET/CT and cellularity tumor parameters expressed by apparent diffusion coefficients (ADC) derived from diffusion-weighted (DW) MRI in untreated and treated patients with head and neck SCC.

METHODS

In 19 patients with no previous exposure to any treatment and 17 different chemo-radiotreated patients with head and neck SCC, we correlated the semi-quantitative uptake values (SUVmax, SUVpeak, and SUVmean) with the ADC functional parameters (ADCmin, ADCmean) including the standard deviation of ADC values (ADCsd).

RESULTS

No significant correlation was found between glucose metabolism parameters and ADCmin or ADCmean in untreated and treated patient groups. However, in untreated patients, significant inverse correlations were found between ADCsd and SUVmax (P = 0.039, r = -0.476), SUVpeak (P = 0.003, r = -0.652) and SUVmean (P = 0.039, r = -0.477). Analyses after chemo-radiotherapy in 17 patients showed no significant correlation between glucose metabolism parameters and DW MRI values, excluding a persistent significant (but lower intensity) inverse correlation between SUVpeak and ADCsd (P = 0.033, r = -0.519).

CONCLUSIONS

The demonstrated relationships suggest complex interactions especially between metabolic activity and heterogeneity of tumoral tissue, which might play a complementary role in the assessment of head and neck SCC.

TRIAL DATE OF REGISTRATION AND REGISTRATION NUMBER

Our retrospective study was registered on April 9th, 2020 by the Ethics Committee of the Coordinating Center "Area Vasta Nord Ovest" (CEAVNO) with Registration Number CEAVNO09042020.

Nasopharyngeal carcinoma in children and adolescents: The EXPeRT/PARTNER diagnostic and therapeutic recommendations

Nasopharyngeal carcinoma (NPC) is a rare pediatric tumor. Collaborative studies performed over the last decades showed improved results compared to historical data, but standardized guidelines for diagnosis and management of pediatric NPC are still unavailable. This study presents a European consensus guideline for the diagnosis and treatment of pediatric NPC developed by the European Cooperative Study Group for Pediatric Rare Tumors (EXPeRT). Main recommendations include induction chemotherapy with cisplatin and 5-flurouracil, concomitant chemoradiotherapy in advanced disease, and to consider maintenance treatment with interferon beta (IFN-β) for selected high-risk patients. Dose adjustments of radiotherapy based on response to induction chemotherapy may decrease the rates of long-term treatment-related complications that affect most of the survivors.

Nomogram for the prediction of primary distant metastasis of nasopharyngeal carcinoma to guide individualized application of FDG PET/CT

PURPOSE

This study aimed to establish an effective nomogram to predict primary distant metastasis (DM) in patients with nasopharyngeal carcinoma (NPC) to guide the application of PET/CT.

METHODS

In total, 3591 patients with pathologically confirmed NPC were consecutively enrolled. The nomogram was constructed based on 1922 patients treated between 2007 and 2014. Multivariate logistical regression was applied to identify the independent risk factors of DM. The predictive value of the nomogram was evaluated using the concordance index (C-index), calibration curve, probability density functions (PDFs), and clinical utility curve (CUC). The results were validated in 1669 patients enrolled from 2015 to 2016. Net reclassification improvement (NRI) was applied to compare performances of the nomogram with other clinical factors. The best cut-off value of the nomogram chosen for clinical application was analyzed.

RESULTS

A total of 355 patients showed primary DM among 3591 patients, yielding an incidence rate of 9.9%. Sex, N stage, EBV DNA level, lactate dehydrogenase level, and hemoglobin level were independent predictive factors for primary DM. C-indices in the training and validation cohort were 0.796 (95% CI, 0.76-0.83) and 0.779 (95% CI, 0.74-0.81), respectively. The NRI indices demonstrated that this model had better predictive performance than plasma EBV DNA level and N stage. We advocate for a threshold probability of 3.5% for guiding the application of PET/CT depending on the clinical utility analyses.

CONCLUSION

This nomogram is a useful tool to predict primary DM of NPC and guide the clinical application of PET/CT individually at the initial staging.

Augmented Whole-Body Scanning via Magnifying PET

A novel technique, called augmented whole-body scanning via magnifying PET (AWSM-PET), that improves the sensitivity and lesion detectability of a PET scanner for whole-body imaging is proposed and evaluated. A Siemens Biograph Vision PET/CT scanner equipped with one or two high-resolution panel-detectors was simulated to study the effectiveness of AWSM-PET technology. The detector panels are located immediately outside the scanner's axial field-of-view (FOV). A detector panel contains 2 ×8 detector modules each consisting of 32 ×64 LSO crystals ( 1.0 ×1.0 ×10.0 mm3 each). A 22Na point source was stepped across the scanner's FOV axially to measure sensitivity profiles at different locations. An elliptical torso phantom containing 7×9 spherical lesions was imaged at different axial locations to mimic a multi-bed-position whole-body imaging protocol. Receiver operating characteristic (ROC) curves were analyzed to evaluate the improvement in lesion detectability by the AWSM-PET technology. Experimental validation was conducted using an existing flat-panel detector integrated with a Siemens Biograph 40 PET/CT scanner to image a torso phantom containing spherical lesions with diameters ranging from 3.3 to 11.4 mm. The contrast-recovery-coefficient (CRC) of the lesions was evaluated for the scanner with or without the AWSM-PET technology. Monte Carlo simulation shows 36%-42% improvement in system sensitivity by a dual-panel AWSM-PET device. The area under the ROC curve is 0.962 by a native scanner for the detection of 4 mm diameter lesions with 5:1 tumor-to-background activity concentration. It was improved to 0.977 and 0.991 with a single- and dual-panel AWSM-PET system, respectively. Experimental studies showed that the average CRC of 3.3 mm and 4.3 mm diameter tumors were improved from 2.8% and 4.2% to 7.9% and 11.0%, respectively, by a single-panel AWSM-PET device. With a high-sensitivity dual-panel device, the corresponding CRC can be further improved to 11.0% and 15.9%, respectively. The principle of the AWSM-PET technology has been developed and validated. Enhanced system sensitivity, CRC and tumor detectability were demonstrated by Monte Carlo simulations and imaging experiments. This technology may offer a cost-effective path to realize high-resolution whole-body PET imaging clinically.

MR-guided simulation is superior than FDG/PET-guided simulation for local control in nasopharyngeal cancer patients treated with intensity-modulated radiotherapy

BACKGROUND

MRI and PET/CT scans are the main supportive methods for nasopharyngeal cancer (NPC) for staging and planning. The aim of this study is to compare MRI and PET/CT scanning in terms of survival in patients with NPC who had MRI or PET/CT-simulated radiotherapy planning.

METHODS

Pathological diagnosed nonkeratinized undifferentiated type and stage II-IVA 91 NPC patients with treated intensity-modulated radiotherapy plus chemotherapy were scanned. The patients were immobilized by a customized thermoplastic mask for fusion images both MRI scans and PET/CT scans. CTVs were created via MR-guided simulation and PET/CT-guided simulation.

RESULTS

PET/CT-guided simulation was performed with 44 patients (56.4%) and MR-guided simulation was performed with 34 patients (43.6%). Local recurrence-free survival (LRFS) of patients was 68.1 months. LRFS of patients with PET/CT-guided simulation was 59.9, while LRFS of patients with MR-guided was 66.9 months. There was a statistically significant difference between groups (P = .03). In the subgroup analyses, the patients were assessed by dividing into the three groups for the T1-T2 stage, T-3 stage, and T-4 stage. In the patients with T1-T2 stage, 5-year LRFS rates were found %74.4 for PET/CT-guided simulation and %83.3 for MR-guided simulation. There was no statistically significant difference between groups (P = .33). In the patients with T-3 stage, 5-year LRFS rates were found %55.6 for PET/CT-guided simulation and %83.3 for MR-guided simulation. There was not a statistically significant difference between groups (P = .59). In the patients with T-4 stage, 5-year LRFS rates were found %42.2 for PET/CT-guided simulation and %85.1 for MR-guided simulation. The difference between groups was found to be statistically significant (P = .04).

CONCLUSION

In this study, we founded that MR-guided simulation has better than PET/CT-guided simulation for LRFS.

Preliminary clinical results for PET/MR compared with PET/CT in patients with nasopharyngeal carcinoma

The present study aimed to assess the performance of positron emission tomography-magnetic resonance imaging (PET/MR) for the visualization and characterization of lesions. In addition, the present study investigated whether the apparent diffusion coefficient (ADC) and intravoxel incoherent motion parameters exhibited any significant correlation with standardized uptake values (SUV) in patients with nasopharyngeal carcinoma (NPC). A total of 35 patients with NPC underwent whole body PET-computed tomography (CT) and head and neck MR imaging (MRI) scans using the PET/CT-MRI system. Image quality, lesion conspicuity and the diagnostic confidence of PET/CT, T1 weighted (T1w) PET/MR and T2w PET/MR imaging were assessed. The true diffusion coefficient (D), the pseudo-diffusion coefficient or diffusion within the microcirculation (D*), and the perfusion fraction or the contribution of water moving in the capillaries (f), and ADC, were calculated. The correlation between the ADC, D*, D and f values and the SUV were analyzed using Pearson's correlation analysis. Similar image quality was obtained using PET/CT, T1w PET/MR and T2w PET/MR imaging. However, the T1w PET/MR and T2w PET/MR imaging were more effective than PET/CT in analyzing the lesion conspicuity of the primary tumors and lymph nodes. In addition, T2w PET/MR imaging was more efficient than T1w PET/MR imaging in analyzing primary tumors and lymph nodes. Pearson's correlation analysis showed no significant correlation between the SUV and ADC, and D*, D and f values in NPC. The present results suggested that the application of PET/MR is feasible and could serve as a reliable alternative to PET/CT, while SUV and ADC, D*, D and f values were identified as independent biomarkers in NPC.

Pre-treatment with angiotensin-(1-7) inhibits tumor growth via autophagy by downregulating PI3K/Akt/mTOR signaling in human nasopharyngeal carcinoma xenografts

Abstract

The highest incidence of nasopharyngeal carcinoma (NPC) is in southeast China, including Taiwan. Many side effects have been observed following radiation therapy with chemotherapy; hence, exploring new treatment modalities for NPC is an important future direction. Angiotensin-(1–7) [Ang-(1–7)] is an endogenous heptapeptide hormone and important component of the renin–angiotensin system that acts through both the Mas receptor and AT2 receptor, exhibiting anti-proliferative and anti-angiogenic properties in cancer cells. However, the anti-cancer activity of Ang-(1–7) related to autophagy in NPC remains largely debated. The effects and signaling pathway(s) involved in the Ang-(1–7)/Mas receptor axis in NPC were investigated both in vitro and in vivo. Ang-(1–7) inhibited cell proliferation, migration, and invasion in NPC-TW01 cells. Ang-(1–7) induced autophagy by increasing the levels of the autophagy marker LC3-II and by enhancing p62 degradation via activation of the Beclin-1/Bcl-2 signaling pathway with involvement of the PI3K/Akt/mTOR and p38 pathways in vitro study. In addition, pre-treatment with Ang-(1–7) inhibited tumor growth in NPC xenografts by inducing autophagy, suggesting a correlation between PI3K/Akt/mTOR pathway inhibition and the abovementioned anti-cancer activities. However, no autophagy was observed following Ang-(1–7) post-treatment. Taken together, these data indicate that Ang-(1–7) plays a novel role in autophagy downstream signaling pathways in NPC, supporting its potential as a therapeutic agent for alleviation the incidence of NPC and preventive treatment of recurrent NPC.

Key messages

Ang-(1–7) inhibits cell proliferation, migration, and invasion by activating autophagy

Ang-(1–7)pre-treatment inhibits tumor growth via autophagy by suppressing PI3K/Akt/mTOR pathway.

Ang-(1–7) may provide a novel preventative treatment for NPC and recurrent NPC

Electronic supplementary material

The online version of this article (10.1007/s00109-018-1704-z) contains supplementary material, which is available to authorized users.

Clinical utility of simultaneous whole-body 18F-FDG PET/MRI as a single-step imaging modality in the staging of primary nasopharyngeal carcinoma

PURPOSE

Both head and neck magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/computed tomography (CT) play a crucial role in the staging of primary nasopharyngeal carcinoma (NPC). In this study, we sought to prospectively investigate the clinical utility of simultaneous whole-body 18F-FDG PET/MRI for primary staging of NPC patients.

METHODS

We examined 113 patients with histologically confirmed NPC who underwent pretreatment, simultaneous whole-body PET/MRI and PET/CT for primary tumor staging. The images obtained with the different imaging modalities were interpreted independently and compared with each other.

RESULTS

PET/MRI increased the accuracy of head and neck MRI for assessment of primary tumor extent in four patients via addition of FDG uptake information to increase the conspicuity of morphologically subtle lesions. PET/MR images were more discernible than PET/CT images for mapping tumor extension, especially intracranial invasion. Regarding the N staging assessment, the sensitivity of PET/MRI (99.5%) was higher than that of head and neck MRI (94.2%) and PET/CT (90.9%). PET/MRI was particularly useful for distinguishing retropharyngeal nodal metastasis from adjacent nasopharyngeal tumors. For distant metastasis evaluation, PET/MRI exhibited a similar sensitivity (90% vs. 86.7% vs. 83.3%), but higher positive predictive value (93.1% vs. 78.8% vs. 83.3%) than whole-body MRI and PET/CT, respectively.

CONCLUSIONS

For tumor staging of NPC, simultaneous whole-body PET/MRI was more accurate than head and neck MRI and PET/CT, and may serve as a single-step staging modality.

Progression of understanding for the role of Epstein-Barr virus and management of nasopharyngeal carcinoma

Nasopharyngeal carcinoma (NPC) is very common in southern China and Southeast Asia. In regions where NPC is endemic, undifferentiated subtypes constitute most cases and are invariably associated with Epstein-Barr virus (EBV) infection, whereas the differentiated subtype is more common in other parts of the world. Undifferentiated NPC is a unique malignancy with regard to its epidemiology, etiology, and clinical presentation. Clinically, NPC is highly invasive and metastatic, but sensitive to both chemotherapy and radiotherapy (RT). Overall prognosis has dramatically improved over the past three decades because of advances in management, including the improvement of RT technology, the broader application of chemotherapy, and more accurate disease staging. Despite the excellent local control with modern RT, distant failure remains a challenging problem. Advances in molecular technology have helped to elucidate the molecular pathogenesis of NPC. This article reviews the contribution of EBV gene products to NPC pathogenesis and the current management of NPC.

Prognostic value of 18F-FDG-PET/CT in patients with nasopharyngeal carcinoma: a systematic review and meta-analysis

BACKGROUND

The prognostic role of 18F-fluorodeoxyglucose positron emission tomography CT (18F-FDG PET/CT) parameters is still controversial in nasopharyngeal carcinoma patients. We sought to perform a systematic review and meta-analysis to explore the prognostic value of maximal standardized uptake value (SUVmax), metabolic tumor volume (MTV) and total lesion glycolysis (TLG) on event-free survival (EFS) and overall survival (OS) in nasopharyngeal carcinoma patients.

RESULTS

Fifteen studies comprising 1,938 patients were included in this study. The combined hazard ratios (HRs) for EFS were 2.63 (95%CI 1.71-4.05) for SUVmax, 2.55 (95%CI 1.49-4.35) for MTV, and 3.32 (95%CI 1.23-8.95) for TLG. The pooled HRs for OS were 2.07 (95%CI 1.54-2.79) for SUVmax, 3.86 (95%CI 1.85-8.06) for MTV, and 2.60 (95%CI 1.55-4.34) for TLG. The prognostic role of SUVmax, MTV and TLG remained similar in the sub-group analyses.

METHODS

A systematic literature search was performed to identify studies which associated 18F-FDG PET/CT to clinical survival outcomes of nasopharyngeal carcinoma patients. The summarized HRs for EFS and OS were estimated by using fixed- or random-effect models according to heterogeneity between trials.

CONCLUSIONS

The present meta-analysis confirms that high values of SUVmax, MTV and TLG predicted a higher risk of adverse events or death in patients with nasopharyngeal carcinoma, despite clinically heterogeneous nasopharyngeal carcinoma patients and the various methods adopted between these studies.

Pathogenesis and FDG-PET/CT findings of Epstein-Barr virus-related lymphoid neoplasms

Epstein-Barr virus (EBV) is one of the most common viruses, infecting more than 90% of the adult population worldwide. EBV genome is detected in some lymphoid neoplasms. Not only their histopathological subtypes, but also their backgrounds and their clinical courses are variable. A number of B-cell lymphoproliferative disorders associated with the immunocompromised state are related to EBV infection. The incidences of these disorders have been increasing along with generalization of organ transplantations and use of immunosuppressive treatments. Furthermore, some EBV-positive lymphoma can also occur in immunocompetent patients. While evaluating patients with generalized lymphadenopathy of unknown cause by positron emission tomography/computed tomography with 2-deoxy-2-[¹⁸F]fluoro-D-glucose (FDG-PET/CT), the possibility of lymphoid neoplasms should be considered in some patients, and a careful review of the background and previous history of the patients is necessary. In this review article, we describe the pathogenesis of EBV-related lymphoid neoplasms and then present FDG-PET/CT images of representative diseases. In addition, we also present a review of other EBV-related diseases, such as infectious mononucleosis and nasopharyngeal carcinoma.

Whole-body 18F-FDG PET/CT for M staging in the patient with newly diagnosed nasopharyngeal carcinoma: Who needs?

OBJECTIVE

Although whole-body fluorine-18 fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/computed tomography (CT) (¹⁸F-FDG PET/CT) is commonly used for M staging of newly diagnosed nasopharyngeal carcinoma (NPC), some patients may not benefit from this procedure. The present study investigated which patients require this modality for M staging.

METHODS

Whole-body ¹⁸F FDG PET/CT results and clinical data were collected for 264 patients with newly diagnosed NPC. The relationships between distant metastasis and age, gender, pathological type, lesion size, SUVmax-T, T staging, N staging, SUVmax-N and Epstein-Barr virus (EBV) quantity were retrospectively analysed to identify factors associated with increased risk.

RESULTS

Of the 264 patients, only 37 (14.0%) were diagnosed with distant metastasis. Using multiple logistic regression analysis, EBV-positivity (OR=13.1; 95% CI:1.61,106.80), N staging (OR=3.05; 95% CI:1.41,6.63) and T staging (OR=2.16; 95% CI:1.10, 4.24) were significantly related to distant metastasis (all P<0.05). EBV DNA levels≥9000copies/ml, N3 stage and T4 stage were identified as high risk factors. A low risk of distant metastasis was found in patients with 0-1 risk factors and in those with 2 specific risk factors, T3/T4 and N2/N3 staging. Patients with EBV DNA levels ≥9000copies/ml and N3 or T4 staging and those with 3 risk factors had a medium or high risk, with a much higher incidence of distant metastasis (χ²=29.896, P=0.000), and needed a whole-body ¹⁸F FDG PET/CT for M staging.

CONCLUSIONS

Due to the low incidence of distant metastasis, only patients with medium or high risk need to undergo a whole-body scan.

Induction of Mitotic Delay in Pharyngeal and Nasopharyngeal Carcinoma Cells Using an Aqueous Extract of Ajuga bracteosa

Nasopharyngeal carcinoma (NPC) is a common cancer in Southeast Asia, for which radiotherapy and/or chemotherapy are the primary treatment methods. Many herbs are known to have potential uses in chemotherapy; however, the mechanisms underlying the observed antitumor activity of Ajuga bracteosa (AB) against NPC remain unclear. We explored the antitumor effects of AB, which was shown specifically to induce mitotic delay in pharyngeal (Detroit 562) and nasopharyngeal (Hone-1) cancer cells. Proliferation of cancer cells after exposure to aqueous extract of A. bracteosa (AEAB) was assessed using the MTT assay. DNA content and cell cycle arrest induction were analyzed using flow cytometry. The expression of checkpoint kinase 2 (CHK2), cell division control protein 2 (CDC2), and cyclin B1 was investigated using qRT-PCR and Western blot analysis. Results indicated the inhibition of cancer cell growth following exposure to AEAB. In addition, AEAB induced the accumulation of G₂/M-phase cells in cancer cell through the disassociation of CDC2/cyclin B1 complex. Our findings suggested that, in addition to the known effects of AEAB in NPC prevention, it may have antitumor activities against NPC cells. In conclusion, AEAB inhibits the growth of and induces mitotic delay in cancer cells, supporting its use as an anticancer agent.

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.

A comparative study of 18F-fluorodeoxyglucose positron emission tomography/computed tomography and (99m)Tc-MDP whole-body bone scanning for imaging osteolytic bone metastases

Background

The objective of this study was to evaluate the feasibility and diagnostic value of ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) and ^99mTc-methylenediphosphonate (MDP) whole-body bone scanning (BS) for the detection of osteolytic bone metastases.

Methods

Thirty-four patients with pathologically confirmed malignancies and suspected osteolytic bone metastases underwent ¹⁸F-FDG PET/CT and ^99mTc-MDP whole-body BS within 30 days. The sensitivity, specificity, and accuracy with respect to the diagnosis of osteolytic bone metastases and bone lesions were compared between the two imaging methods.

Results

The sensitivity, specificity, and accuracy of ¹⁸F-FDG PET/CT for the diagnosis of osteolytic bone metastases were 94.3% (95% confidence interval [CI], 91.6–96.2%), 83.3% (95% CI, 43.6–96.9%), and 94.2% (95% CI, 91.5–96.1%), respectively. It was found that ^99mTc-MDP whole-body BS could discriminate between patients with 50.2% (95% CI, 45.4–55.1%) sensitivity, 50.0% (95% CI, 18.8–81.2%) specificity, and 50.2% (95% CI, 45.5–55.1%) accuracy. ¹⁸F-FDG PET/CT achieved higher sensitivity, specificity, and accuracy in detecting osteolytic bone metastases than 99mTc-MDP whole-body BS (p<0.001).

Conclusions

F-FDG PET/CT has a higher diagnostic value than ^99mTc-MDP whole-body BS in the detection of osteolytic bone metastases, especially in the vertebra.

Diagnostic value of 18F-FDG PET/CT in comparison to bone scintigraphy, CT and 18F-FDG PET for the detection of bone metastasis

PURPOSE

To evaluate the diagnostic value of 18F-FDG PET/CT for detection of bone metastasis in comparison with the efficacies of 18F-FDG PET/CT, CT, 18F-FDG PET and conventional planar bone scintigraphy in a series of cancer patients.

METHODS

Five hundred and thirty patients who underwent both 18F-FDG PET/CT and bone scintigraphy within 1 month were retrospectively analyzed. The skeletal system was classified into 10 anatomic segments and interpreted blindly and separately. For each modality, the sensitivity, specificity, accuracy, PPV and NPV were calculated and the results were statistically analyzed.

RESULTS

Bone metastases were confirmed in 117 patients with 459 positive segments. On patient-based analysis, the sensitivity, specificity, accuracy, PPV and NPV of 18F-FDG PET/CT were significantly higher than bone scintigraphy, CT and 18F-FDG PET (P<0.05). On segment-based analysis, the sensitivity of CT, bone scintigraphy, 18F-FDG PET and 18F-FDG PET/CT were 70.4%, 89.5%, 89.1% and 97.8%, respectively (P<0.05, compared with 18F-FDG PET/CT). The overall specificity and accuracy of the four modalities were 89.1%, 91.8%, 90.3%, 98.2% and 90.3%, 90.9%, 89.8%, 98.0%, respectively (P<0.05, compared with 18F-FDG PET/CT). The PPV and NPV were 89.8%, 87.6%, 85.6%, 97.2% and 85.6%, 93.2%, 92.8%, 98.6%, respectively. Three hundred and twelve lesions or segments were presented as lytic or sclerotic changes on CT images at the corresponding sites of increased 18F-FDG uptake. In lytic or mixed lesions, the sensitivity of 18F-FDG PET/CT and 18F-FDG PET were better than bone scintigraphy, while in osteoblastic lesions bone scintigraphy had a similar performance with 18F-FDG PET/CT but better than 18F-FDG PET alone.

CONCLUSION

Our data allow the conclusion that 18F-FDG PET/CT is superior to planar bone scintigraphy, CT or 18F-FDG PET in detecting bone metastasis. 18F-FDG PET/CT may enhance our diagnosis of tumor bone metastasis and provide more information for cancer treatment.

Emerging treatment options for nasopharyngeal carcinoma

Nasopharyngeal carcinoma is endemic in Asia and is etiologically associated with Epstein–Barr virus. Radiotherapy is the primary treatment modality. The role of systemic therapy has become more prominent. Based on multiple phase III studies and meta-analyses, concurrent cisplatin-based chemoradiotherapy is the current standard of care for locally advanced disease (American Joint Committee on Cancer manual [7th edition] stages II–IVb). The reported failure-free survival rates from phase II trials are encouraging for induction + concurrent chemoradiotherapy. Data from ongoing phase III trials comparing induction + concurrent chemoradiotherapy with concurrent chemoradiotherapy will validate the results of these phase II studies. Intensity-modulated radiotherapy techniques are recommended if the resources are available. Locoregional control exceeding 90% and reduced xerostomia-related toxicities can now be achieved using intensity-modulated radiotherapy, although distant control remains the most pressing research problem. The promising results of targeted therapy and Epstein–Barr virus-specific immunotherapy from early clinical trials should be validated in phase III clinical trials. New technology, more effective and less toxic chemotherapy regimens, and targeted therapy offer new opportunities for treating nasopharyngeal carcinoma.