Validation of the 8th edition of the UICC/AJCC staging system for nasopharyngeal carcinoma treated with intensity-modulated radiotherapy

Serum LINC00339 is a promising biomarker for prognosis prediction of nasopharyngeal carcinoma

BACKGROUND

Long non-coding RNAs (lncRNAs) in serum were useful and promising biomarkers for diagnostic and prognostic application. Herein, we investigated the serum lncRNA LINC00339 expression and its role in nasopharyngeal carcinoma.

METHODS

In this study, we recruited a cohort of 129 nasopharyngeal carcinoma patients, 68 patients with nasopharyngitis, and 80 healthy controls. Serum LINC00339 levels were measured by reverse transcription-quantitative polymerase chain reaction. Receiver operating characteristic (ROC) and Kaplan-Meier curve analyses were conducted to evaluate th e clinical role of LINC00339. The effects of linc00339 on cellular activities were measured using CCK-8 and Transwell assays.

RESULTS

We observed that serum LINC00339 expression was upregulated in nasopharyngeal carcinoma patients and closely associated with tumor node metastasis stage, lymph node metastasis, and overall survival rate. Meanwhile, ROC analysis showed serum LINC00339 had diagnostic value to distinguish nasopharyngeal carcinoma patients from healthy individuals and nasopharyngitis patients. Silencing of LINC00339 could repress cellular behaviors by targeting miR-152.

CONCLUSION

This study clarified that LINC00339 was upregulated in nasopharyngeal carcinoma, and that serum LINC00339 may act as a diagnostic or prognostic marker, and a hopeful therapeutic target for patients with nasopharyngeal carcinoma.

Enhancing Nasopharyngeal Carcinoma Survival Prediction: Integrating Pre- and Post-Treatment MRI Radiomics with Clinical Data

Recurrences are frequent in nasopharyngeal carcinoma (NPC) despite high remission rates with treatment, leading to considerable morbidity. This study aimed to develop a prediction model for NPC survival by harnessing both pre- and post-treatment magnetic resonance imaging (MRI) radiomics in conjunction with clinical data, focusing on 3-year progression-free survival (PFS) as the primary outcome. Our comprehensive approach involved retrospective clinical and MRI data collection of 276 eligible NPC patients from three independent hospitals (180 in the training cohort, 46 in the validation cohort, and 50 in the external cohort) who underwent MRI scans twice, once within 2 months prior to treatment and once within 10 months after treatment. From the contrast-enhanced T1-weighted images before and after treatment, 3404 radiomics features were extracted. These features were not only derived from the primary lesion but also from the adjacent lymph nodes surrounding the tumor. We conducted appropriate feature selection pipelines, followed by Cox proportional hazards models for survival analysis. Model evaluation was performed using receiver operating characteristic (ROC) analysis, the Kaplan-Meier method, and nomogram construction. Our study unveiled several crucial predictors of NPC survival, notably highlighting the synergistic combination of pre- and post-treatment data in both clinical and radiomics assessments. Our prediction model demonstrated robust performance, with an accuracy of AUCs of 0.66 (95% CI: 0.536-0.779) in the training cohort, 0.717 (95% CI: 0.536-0.883) in the testing cohort, and 0.827 (95% CI: 0.684-0.948) in validation cohort in prognosticating patient outcomes. Our study presented a novel and effective prediction model for NPC survival, leveraging both pre- and post-treatment clinical data in conjunction with MRI features. Its constructed nomogram provides potentially significant implications for NPC research, offering clinicians a valuable tool for individualized treatment planning and patient counseling.

A machine learning approach for predicting radiation-induced hypothyroidism in patients with nasopharyngeal carcinoma undergoing tomotherapy

The purpose of this study was to establish an integrated predictive model that combines clinical features, DVH, radiomics, and dosiomics features to predict RIHT in patients receiving tomotherapy for nasopharyngeal carcinoma. Data from 219 patients with nasopharyngeal carcinoma were randomly divided into a training cohort (n = 175) and a test cohort (n = 44) in an 8:2 ratio. RIHT is defined as serum thyroid-stimulating hormone (TSH) greater than 5.6 μU/mL, with or without a decrease in free thyroxine (FT4). Clinical features, 27 DVH features, 107 radiomics features and 107 dosiomics features were extracted for each case and included in the model construction. The least absolute shrinkage and selection operator (LASSO) regression method was used to select the most relevant features. The eXtreme Gradient Boosting (XGBoost) was then employed to train separate models using the selected features from clinical, DVH, radiomics and dosiomics data. Finally, a combined model incorporating all features was developed. The models were evaluated using receiver operating characteristic (ROC) curves and decision curve analysis. In the test cohort, the area under the receiver operating characteristic curve (AUC) for the clinical, DVH, radiomics, dosiomics and combined models were 0.798 (95% confidence interval [CI], 0.656-0.941), 0.673 (0.512-0.834), 0.714 (0.555-0.873), 0.698 (0.530-0.848) and 0.842 (0.724-0.960), respectively. The combined model exhibited higher AUC values compared to other models. The decision curve analysis demonstrated that the combined model had superior clinical utility within the threshold probability range of 1% to 79% when compared to the other models. This study has successfully developed a predictive model that combines multiple features. The performance of the combined model is superior to that of single-feature models, allowing for early prediction of RIHT in patients with nasopharyngeal carcinoma after tomotherapy.

Multi‑parameter quantitative magnetic resonance imaging in the early assessment of radiation‑induced parotid damage in patients with nasopharyngeal carcinoma following intensity‑modulated radiotherapy

The present study aimed to investigate the value of intravoxel incoherent motion imaging (IVIM) and three-dimensional pulsed continuous arterial spin labeling (ASL) in assessing dynamic changes of the parotid gland in patients with nasopharyngeal carcinoma (NPC) following radiotherapy (RT). A total of 18 patients with NPC who underwent intensity-modulated RT were enrolled in the present study. All patients underwent conventional magnetic resonance imaging, plus IVIM and ASL imaging of the bilateral parotid glands within 2 weeks prior to RT, and 1 week (1W) and 3 months (3M) following RT. Pure diffusion coefficient (D), pseudo-diffusion coefficient (D*), perfusion fraction (F) and blood flow (BF) were analyzed. D and BF values were significantly increased from pre-RT to 1W post-RT [change rate: Median (IQR), ΔD1W%: 39.28% (38.23%) and ΔBF1W%: 60.84% (54.88%)] and continued to increase from 1W post-RT to 3M post-RT [55.44% (40.56%) and ΔBF%: 120.39% (128.74%)]. In addition, the F value was significantly increased from pre-RT to 1W post-RT, [change rate: Median (IQR), ΔF1W%: 28.13% (44.66%)], and this decreased significantly from 1W post-RT to 3M post-RT. However, no significant differences were observed between pre-RT and 3M post-RT. Results of the present study also demonstrated that the D* value was significantly decreased from pre-RT to 1W post-RT and 3M post-RT [change rate: Median (IQR), ΔD*1w%: -41.86% (51.71%) and ΔD*3M: -29.11% (42.67%)]. No significant difference was observed between the different time intervals post-RT. There was a significant positive correlation between percentage change in ΔBF1W and radiation dose (ρ=0.548, P=0.001). Thus, IVIM-diffusion-weighted imaging and ASL may aid in the detection and prediction of radiation-induced parotid damage in the early stages following RT. They may contribute to further understanding the potential association between damage to the parotid glands and patient-/treatment-related variables, through the assessment of individual microcapillary perfusion and tissue diffusivity.

Precision Medicine for Nasopharyngeal Cancer-A Review of Current Prognostic Strategies

Nasopharyngeal carcinoma (NPC) is an Epstein-Barr virus (EBV) driven malignancy arising from the nasopharyngeal epithelium. Current treatment strategies depend on the clinical stage of the disease, including the extent of the primary tumour, the extent of nodal disease, and the presence of distant metastasis. With the close association of EBV infection with NPC development, EBV biomarkers have shown promise in predicting treatment outcomes. Among the omic technologies, RNA and miRNA signatures have been widely studied, showing promising results in the research setting to predict treatment response. The transformation of radiology images into measurable features has facilitated the use of radiomics to generate predictive models for better prognostication and treatment selection. Nonetheless, much of this work remains in the research realm, and challenges remain in clinical implementation.

Impact of independent multidisciplinary work on the survival rate of stage 3 and 4 nasopharyngeal cancer in Indonesia: a retrospective cohort study

Background

The utilization of a multidisciplinary team (MDT) strategy is a beneficial approach in integrating the knowledge and proficiencies of various fields to produce thorough and advantageous cancer treatment plans for patients. Nevertheless, MDT has yet to be widely adopted in Indonesia. In this study, the authors examined an early form of MDT in Indonesia that does not involve dedicated meetings, referred as independent multidisciplinary work (IMW). The objective is to investigate the differences in survival rates of nasopharyngeal cancer (NPC) patients who underwent treatment with and without IMW.

Materials and methods

This study has a retrospective cohort design. Data were collected from the medical records of newly diagnosed stage 3 and 4 NPC patients between 2016 and 2018. The subjects were divided into two groups: the IMW group and the non-IMW group. The primary end point of the study is overall survival rate between the two groups. Kaplan-Meier survival analysis, log-rank test, and cox proportional hazard analysis were used for statistical analysis.

Results

This study included a total of 124 patients with NPC, 81 patients in the IMW group and 43 patients in the non-IMW group. At the end of the 36-month follow-up period, the median survival of the IMW group was not reached, while in the non-IMW, it was 12 months [95% confidence intervals (95% CI), 8.78-15.22], hazard ratio (HR): 0.47 (95% CI, 0.28-0.78; P<0.01). The 1-year survival rate was 66.7% in the IMW group versus 46.5% in the non-IMW group (HR=0.7, 95% CI 0.49-0.99; P=0.03); the 2-year survival rate was 40.7% in the IMW group versus 16.3% in the non-IMW group (HR=0.4, 95% CI 0.19-0.83; P<0.01). Daniel Rizky, Vina Yunarvika, and Yasjudan Rastrama Putra, these authors contributed equally to this work. In the multivariate analysis, the IMW approach, ECOG (The Eastern Cooperative Oncology Group) status, distant metastasis, and treatment approach were significantly associated with survival outcome.

Conclusion

The use of IMW approach in the treatment of NPC was associated with a better survival outcome compared to non-IMW treatment.

Functional mechanism and clinical implications of miR-141 in human cancers

Cancer is caused by the abnormal proliferation of local tissue cells under the control of many oncogenic factors. MicroRNAs (miRNAs) are a class of evolutionarily conserved, approximately 22-nucleotide noncoding small RNAs that influence transcriptional regulationby binding to the 3'-untranslated region of target messenger RNA. As a member of the miRNA family, miR-141 acts as a suppressor or an oncomiR in various cancers and regulates cancer cell proliferation, apoptosis, invasion, and metastasis through a variety of signaling pathways, such as phosphatidylinositol-3-kinase (PI3K)/protein kinase B (AKT) and constitutive activation of nuclear factor-κB (NF-κB). Target gene validation and pathway analysis have provided mechanistic insight into the role of this miRNA in different tissues. This review also outlines novel findings that suggest miR-141 may be useful as a noninvasive biomarker and as a therapeutic target in several cancers.

Identification of DNA aptamers that specifically targets EBV+ nasopharyngeal carcinoma via binding with EphA2/CD98hc complex

Nasopharyngeal carcinoma (NPC) is one of the Epstein-Barr virus (EBV)-associated malignancies and has a distinct geographical distribution. The high mortality rates of NPC patients with advanced and recurrent disease highlight the urgent need for biomarkers for early diagnosis and effective treatments. In this study, we developed DNA aptamers that specifically bind to EBV positive NPC cells by the Cell-SELEX procedure. We further identified the EphA2 (ephrin type-A receptor 2)/CD98hc (CD98 heavy chain) complex as the potential target of the aptamer EA-3 by combining aptamer-based separation and mass spectrometry analysis. Our results revealed for the first time that EphA2 colocalized with CD98hc at the plasma membrane and EphA2 coimmunoprecipitated with CD98hc, which may serve as a starting point for exploring the potential functions of the complex of EphA2 and CD98hc in NPCs. Here, we demonstrated that aptamers can be useful for the identification of protein complexes on the surface of cancer cells.

Sensorineural Hearing Loss in Nasopharyngeal Carcinoma Survivors in the Modern Treatment Era - The Early and Late Effects of Radiation and Cisplatin

AIMS

Hearing loss is a common debilitating complication in nasopharyngeal carcinoma (NPC) survivors. The aim of the present study was to investigate the impact of inner ear/cochlear radiation dose and cisplatin use on early and late sensorineural hearing loss (SNHL) in NPC patients treated with radiotherapy alone, concurrent chemoradiation (cCRT) and induction chemotherapy followed by cCRT (iCRT) in the intensity-modulated radiotherapy era.

MATERIALS AND METHODS

The study included 81 NPC patients treated with intensity-modulated radiotherapy between 2014 and 2016. Pure tone audiometry was carried out at baseline and follow-up. The effects of cochlear/inner ear radiation and cisplatin doses on early (<12 months) and late (≥24 months) SNHL were analysed using multivariable regression after adjusting for important predictors.

RESULTS

In total, 156 ears were examined. In early SNHL (n = 136), cisplatin use predicted the incidence of early high-frequency SHNL (HF-SNHL) (odds ratio 6.4, 95% confidence interval 1.7-23.9, P = 0.005). Ninety ears were analysed for late SNHL (median follow-up 38 months). Inner ear/cochlear radiation and cisplatin doses and better pre-treatment hearing were independent predictors of threshold change at 4 kHz. Every 10 Gy increase in inner ear/cochlear Dmean resulted in 5-dB and 6-dB threshold changes, respectively (cochlear Dmean: B = 0.005, 95% confidence interval 0.0004-0.009, P = 0.031; inner ear Dmean: B = 0.006, 95% confidence interval 0.001-0.010, P = 0.014). Cisplatin use was associated with late HF-SNHL (odds ratio 3.74, 95% confidence interval 1.1-12.3, P = 0.031). In the cCRT and iCRT subgroups, no cisplatin dose-dependent ototoxicity was observed. Severe (≥30 dB) late HF-SNHL occurred in 14% and 25% of the patients when the cochlear dose constraints were 40 Gy and 44 Gy, respectively. The radiotherapy-alone group did not develop severe late HF-SNHL.

CONCLUSION

Cochlear/inner ear radiation dose and cisplatin use showed differential and independent ototoxicity in early and late SNHL. As cochlear/inner ear dose-dependent ototoxicity was demonstrated, the cochlear dose constraint should be as low as reasonably achievable, especially when cisplatin is also administered.

Long-term Therapeutic Outcome and Prognostic Factors of Patients with Nasopharyngeal Carcinoma Receiving Intensity-modulated Radiotherapy: An Analysis of 608 Patients from Low-endemic Regions of China

OBJECTIVE

To evaluate the long-term outcome and prognostic factors of patients with nasopharyngeal carcinoma (NPC) from low-endemic regions of China who received definitive intensity-modulated radiation therapy (IMRT).

METHODS

The clinical data from 608 patients with newly-diagnosed non-metastatic NPC who have received initial treatment at our cancer center from January, 2008 to December, 2013 were retrospectively reviewed. All patients received definitive IMRT, and 87.7% received platinum-based chemotherapy.

RESULTS

The median follow-up duration was 51 months (follow-up rate, 98.5%; range, 10-106 months) for the entire cohort. The 5-year overall survival rate was 79.7%. The 5-year local relapse-free survival rate, regional relapse-free survival rate, distant metastasis-free survival rate and progression-free survival rate were 92.4%, 93.3%, 79.2% and 74.3%, respectively. A total of 153 patients had experienced treatment failure, with distant metastasis as the primary cause in 77.1% (118/153). Patients with T4 or N3 diseases had a significantly poorer prognosis than other subcategories. Stage T4 and N3 were closely associated with distant metastasis, with the metastatic rate of 29.3% and 45.5%, respectively.

CONCLUSION

IMRT provides patients with non-metastatic NPC with satisfactory long-term survival. Both T stage and N stage are important prognostic factors for NPC patients. Patients with T4 or N3 diseases have significantly increased distant metastatic rates and poor survival time.

HOXA11-AS induces cisplatin resistance by modulating the microRNA-98/PBX3 axis in nasopharyngeal carcinoma

Long non-coding RNA homeobox A11-antisense RNA (HOXA11-AS) has been implicated in cisplatin (DDP) resistance in multiple types of cancer. The purpose of the present study was to investigate the role of HOXA11-AS in DDP-resistant nasopharyngeal carcinoma (NPC) cells. The expression levels of HOXA11-AS were examined using reverse transcription-quantitative PCR. Cell viability was measured using a Cell Counting Kit-8 assay, and a TUNEL assay was utilized to assess cell apoptosis. The expression levels of apoptosis-related factors (Bax and Bcl-2) were detected by western blot analysis. The interaction between microRNA-98 (miR-98) and HOXA11-AS or pre-B-cell leukemia homeobox 3 (PBX3) was demonstrated using bioinformatics analysis, dual-luciferase reporter assays and RNA immunoprecipitation assays. HOXA11-AS and PBX3 expressions levels were upregulated, whereas miR-98 levels were downregulated in DDP-resistant NPC tissues. Patients with NPC with high HOXA11-AS expression had a low survival rate. Knockdown of HOXA11-AS enhanced the DDP sensitivity of DDP-resistant NPC (5-8F/DDP and SUNE1/DDP) cells, which was demonstrated by the accelerated apoptosis. In addition, HOXA11-AS inhibited the expression levels of miR-98 through direct interaction. Furthermore, miR-98 inhibition counteracted the inductive effect of HOXA11-AS-knockdown on the DDP sensitivity of NPC cells. PBX3 was a target of miR-98 and was positively modulated by HOXA11-AS. Overexpression of PBX3 reversed the suppressive effect of HOXA11-AS silencing on the DDP resistance of NPC cells. The data demonstrated that HOXA11-AS enhanced DDP resistance in NPC via the miR-98/PBX3 axis, providing a potential therapeutic target for patients with DDP-resistant NPC.

Integration of Antiangiogenic Therapy with Cisplatin and Gemcitabine Chemotherapy in Patients with Nasopharyngeal Carcinoma

PURPOSE

Induction cisplatin and gemcitabine chemotherapy is a standard treatment for locally advanced nasopharyngeal carcinoma (NPC). Inhibition of VEGF axis has been shown to promote maturation of microvasculature and improve perfusion. We conducted a four-arm study to assess the effect of two doses of either sunitinib or bevacizumab with chemotherapy in NPC.

PATIENTS AND METHODS

Patients with treatment-naïve locally advanced NPC were treated with three cycles of 3-weekly cisplatin and gemcitabine preceded by 1 week of anti-VEGF therapy for each cycle, followed by standard concurrent chemoradiation: arm A patients received 7 days of 12.5 mg/day sunitinib; arm B 7 days of 25 mg/day sunitinib; arm C bevacizumab 7.5 mg/kg infusion; arm D bevacizumab 2.5 mg/kg infusion. Patients with metastatic NPC were treated with up to six cycles of similar treatment without concurrent chemoradiation.

RESULTS

Complete metabolic response (mCR) by whole body ¹⁸FDG PET was highest in arm C (significant difference in four groups Fisher exact test P = 0.001; type 1 error = 0.05), with 42% mCR (95% confidence interval, 18-67) and 3-year relapse-free survival of 88% in patients with locally advanced NPC. Significant increase in pericyte coverage signifying microvascular maturation and increased immune cell infiltration was observed in posttreatment tumor biopsies in Arm C. Myelosuppression was more profound in sunitinib containing arms, and tolerability was established in arm C where hypertension was the most significant toxicity.

CONCLUSIONS

Bevacizumab 7.5 mg/kg with cisplatin and gemcitabine was well tolerated. Promising tumor response was observed and supported mechanistically by positive effects on tumor perfusion and immune cell trafficking into the tumor.

Validation of Stage N3 of the Eighth Edition AJCC Staging System for Nasopharyngeal Carcinoma

OBJECTIVES

To validate stage nodal (N)3 of the 8th edition American Joint Committee on Cancer (AJCC) staging system for nasopharyngeal carcinoma (NPC).

METHODS

This retrospective cohort study extracted NPC patients from the Surveillance, Epidemiology, and End Results database between 2004 and 2016. Pathologically confirmed patients with complete data of level IV, N3a, and N3b lymph node metastasis were investigated. The included patients were divided into level IV, N3a, and N3b groups. Five-year overall survival (OS) and cancer-specific survival (CSS) were compared among the three groups.

RESULTS

A total of 693 patients were included: 285 (41.13%) patients in the level IV group, 124 (17.89%) patients in the N3a group, and 284 (40.98%) patients in the N3b group. The 5-year OS (57.1%, 55.0%, and 55.2%) and CSS (64.4%, 63.5%, and 64.4%) were not different among the level IV, N3a, and N3b groups. Multivariate regression analysis revealed that N stage was not an independent prognostic factor for OS (hazard ratio [HR] = 1.03, 95% confidence interval [CI]: 0.91-1.17; P = .65) or CSS (HR = 1.03, 95% CI: 0.89-1.19; P = .70).

CONCLUSION

Stage N3 of the 8th edition AJCC staging system for NPC is reasonable.

LEVEL OF EVIDENCE

III Laryngoscope, 131:535-540, 2021.

Survival impacts of different nodal characteristics and T-classification in N3 nasopharyngeal carcinoma patients

OBJECTIVES

We investigated the survival impacts of various nodal characteristics and T-classification on nasopharyngeal carcinoma (NPC) patients with the 8th AJCC/UICC staging criteria N3.

MATERIALS AND METHODS

Pretreatment MRIs from 110 staged N3 NPC patients were reviewed. There were 23 T1, 25 T2, 32 T3, and 30 T4, respectively. All except one patient belonged to WHO type II pathology. All patients received curative radiotherapy 68.0-76.8 Gy plus different chemotherapy, including induction, concurrent, adjuvant or any combination. Various endpoints, including OS (overall survival), DFS (disease-free survival), LRFFS (locoregional failure-free survival), DMFFS (distant metastasis failure-free survival) were compared between different nodal characteristics and T-classification.

RESULTS

There were no statistically significant differences in all analyzed survival curves between various nodal characteristics, including unilateral N3 vs. bilateral N3, "large" nodes (>6 cm) alone vs. "low" nodes (below the caudal border of cricoid cartilage) alone vs. combined "large" and "low" nodes, risk score 1 vs. 2 vs. 3 vs. 4 (by counting the sum of "large" and "low" nodes in the same case), and radiologic extra-nodal extension. Patients with T4, compared with those of T1-3 have worse OS (5-year rates, 42.2% vs. 82.8%, P < 0.0001), DFS (5-year rates, 43.9% vs. 68.9%, P = 0.0037), LRFFS (5-year rates, 69.3% vs. 82.7%, P = 0.0432), and DMFFS (5-year rates, 57.2% vs. 77.7%, P = 0.0163).

CONCLUSIONS

Our results support merging previous N3a and N3b as a N3 category in the 8th edition new staging system. Patients with T4N3 diseases have extremely poor outcome and deserve to strengthen the treatment intensity in future trials.

Comparison between the seventh and eighth edition of the AJCC/UICC staging system for nasopharyngeal cancer integrated with pretreatment plasma Epstein–Barr virus DNA level in a non-Chinese population: secondary analysis from a prospective randomized trial

The eighth AJCC/UICC staging for nasopharyngeal cancer had higher prognostic values than the previous edition. Pretreatment plasma EBV DNA integrated into the next edition could further improve the outcome prediction.

A simplified T classification based on the 8th edition of the UICC/AJCC staging system for nasopharyngeal carcinoma

Objective: This study aimed to establish a simplified T classification based on the 8th edition of the Union for International Cancer Control/American Joint Committee on Cancer (UICC/AJCC) staging system for nasopharyngeal carcinoma (NPC).

Methods: In total, 325 patients with NPC were included in this study. All patients underwent magnetic resonance imaging, and the staging criteria were recorded. These patients were subjected to staging with the 8th edition of the UICC/AJCC staging system for NPC.

Results:  Involvement of the oropharynx, nasal cavity, adjacent soft tissue (medial pterygoid, lateral pterygoid, and prevertebral muscles), cervical vertebra, orbit, and hypopharynx were always accompanied by other equivalently or more advanced T-stage classifications. All cases with involvement of the paranasal sinuses showed skull base erosion. The majority of cases with involvement of the pterygoid structure showed skull base erosion.

Conclusion: According to the simplification principle, the following new T classification based on the 8th edition of the UICC/AJCC staging system was established: T1, tumor confined to nasopharynx, or beyond the nasopharynx without parapharyngeal involvement; T2, tumor with extension to the parapharyngeal space; T3, tumor with infiltration to bony structures at the skull base; T4, tumor with intracranial extension, involvement of the cranial nerves or parotid gland, and/or extensive soft tissue infiltration beyond the lateral surface of the lateral pterygoid muscle. Validation with a large series of patients is needed.

Treatment Response Prediction of Nasopharyngeal Carcinoma Based on Histogram Analysis of Diffusional Kurtosis Imaging

BACKGROUND AND PURPOSE

The prediction of treatment response is important in planning and modifying the chemoradiation therapy regimen. This study aimed to explore the quantitative histogram indices for treatment-response prediction of nasopharyngeal carcinoma based on diffusional kurtosis imaging compared with a standard ADC value (ADC_standard).

MATERIALS AND METHODS

Thirty-six patients with an initial diagnosis of locoregionally advanced nasopharyngeal carcinoma and diffusional kurtosis imaging acquisitions before and after neoadjuvant chemotherapy were enrolled. Patients were divided into respond-versus-nonrespond groups after neoadjuvant chemotherapy and residual-versus-nonresidual groups after radiation therapy. Histogram parameters of diffusional kurtosis imaging-derived parameters (ADC, ADC coefficient corrected by the non-Gaussain model [D], apparent kurtosis coefficient without a unit [K]) were calculated. The ADC_standard was calculated on the basis of intravoxel incoherent movement data. The intraclass correlation coefficient, Kolmogorov-Smirnov test, Student t test or Mann-Whitney U test, and receiver operating characteristic analysis were performed.

RESULTS

Most of the parameters had good-to-excellent consistency (intraclass correlation coefficient = 0.675-0.998). The pre-ADC_standard, pre-ADC (10th, 25th, 50th percentiles), pre-D (10th, 25th, 50th percentiles), and pre-K_50th were significantly different between the respond and nonrespond groups, while the pre-ADC_10th, pre-K_90th, post-ADC_50th, post-K_75th, post-K_90th, and the percentage change of parameters before and after neoadjuvant chemotherapy (▵ADC_50th%) were significantly different between the residual and nonresidual groups (all P < .05). Receiver operating characteristic analysis indicated that setting pre-D_50th = 0.875 × 10^-3mm²/s as the cutoff value could result in optimal diagnostic performance for neoadjuvant chemotherapy response prediction (area under the curve = 0.814, sensitivity = 0.70, specificity = 0.92), while the post-K_90th = 1.035 (area under the curve = 0.829, sensitivity = 0.78, specificity = 0.72), and▵ADC_50th% = 0.253 (area under the curve = 0.833, sensitivity = 0.94, specificity = 0.72) were optimal for radiation therapy response prediction.

CONCLUSIONS

Histogram analysis of diffusional kurtosis imaging may potentially predict the neoadjuvant chemotherapy and short-term radiation therapy response in locoregionally advanced nasopharyngeal carcinoma, therefore providing evidence for modification of the treatment regimen.

Surrogate endpoints shortening the therapeutic evaluation duration for different subgroups of patients with nasopharyngeal carcinoma receiving intensity-modulated radiotherapy: A retrospective analysis of 830 patients stratified by the 8th edition of the UICC/AJCC staging system and plasma Epstein-Barr viral

Purpose: Investigating surrogate endpoints shortening the time of therapeutic evaluation in nasopharyngeal carcinoma (NPC) after radical treatment.

Patients and Methods: We retrospectively analyzed 830 patients receiving intensity-modulated radiotherapy (IMRT) from 2008 to 2010 and being stratified by the 8th edition of UICC/AJCC staging system and the plasma Epstein-Barr virus DNA (EBV DNA). The annual rates of overall survival (OS), progression-free survival (PFS), loco-regional recurrence-free survival (LRFS), and distant metastasis-free survival (DMFS) were sequentially calculated using the life table and compared by the McNemar method.

Results: The time of shortening therapeutic evaluation by surrogate endpoints: OS, PFS, LRFS and DMFS could be shortened to 1-year (100% vs 100%, P=1) in patients with stage I; OS, PFS, LRFS and DMFS could be shortened to 3-year (96.9% vs 96.1%, P = 1; 94.6% vs 92.2%, P = 0.125; 96.9% vs 95.3%, P = 0.5) and 4-year (92.2% vs 91.2%, P = 0.125) in stage II; In the high EBV DNA group , OS and DMFS could be shortened to 1-year (100% vs 100%, P = 1;100% vs 100%, P = 0.25) in stage II; OS and PFS could be shortened to 3-year (94.3% vs 91.4%, P = 1;82.9% vs 74.3%, P = 0.25) in stage III; OS could be shortened to 4-year (75% vs 72.7%, P = 1) in stage IVA.

Conclusions: The time of therapeutic evaluation could be shortened to <5-year in stages I-II patients. The year of surrogate endpoints could be ahead in stages II-IVA with high EBV DNA.