New T staging recommendations for recurrent nasopharyngeal carcinoma.

OBJECTIVE: The International Union for Cancer Control/American Joint Committee on Cancer (UICC/AJCC) rT staging is not clinically practical for recurrent nasopharyngeal carcinoma (rNPC). The aim of this study was to establish a new rT staging to guide the treatment of rNPC. METHODS: We conducted a retrospective analysis of 175 patients diagnosed with rNPC between January 2012 and December 2020, using ROC curve analysis to evaluate its effectiveness. RESULTS: We analyzed the overall survival (OS) and progression-free survival(PFS) of patients diagnosed with rNPC according to the 8th (UICC/AJCC) rT staging, and found that the overall survival of rT1 and rT2 patients (OS; 29.98% vs. 27.09%, p = 0.8059) and progression-free survival (PFS; 28.48% vs. 26.12%, p = 0.4045) had no significant difference. In rT1 and rT2 patients of this study, overall survival(OS; 30.44% vs. 24.91%, p = 0.0229) and progression-free survival(PFS 29.12% vs. 24.03%, p = 0.0459) had a significant difference. Smoking, family history, and time interval of initial recurrence were independent prognostic factors for OS and PFS. CONCLUSION: The new rT staging of this study has a better predictive value for survival of rNPC patients than the 8th (UICC/AJCC) rT staging.

Normal tissue complication probability model of temporal lobe injury following re-irradiation of IMRT for local recurrent nasopharyngeal carcinoma.

Purpose: We tried to establish the normal tissue complication probability (NTCP) model of temporal lobe injury of recurrent nasopharyngeal carcinoma (NPC) patients after two courses of intensity modulated radiotherapy (IMRT) to provide more reliable dose-volume data reference to set the temporal lobe tolerance dose for recurrent NPC patients in the future. Methods and materials: Recurrent NPC patients were randomly divided into training data set and validation data set in a ratio of 2:1, All the temporal lobes (TLs) were re-contoured as R/L structures and named separately in the MIM system. The dose distribution of the initial IMRT plan was deformed into the second course planning CT via MIM software to get the deformed dose. Equivalent dose of TLs in 2Gy fractions was calculated via linear quadratic model, using an α/ß=3 for temporal lobes. NTCP model that correlated the irradiated volume of the temporal lobe and? the clinical variables were evaluated in a multivariate prediction model using AUC analysis. Results: From Jan. 2010 to Dec. 2020, 78 patients were enrolled into our study. Among which 26 (33.3%) developed TLI. The most important factors affecting TLI was the sum-dose d1.5cc of TL, while the possible clinical factors did not reach statistically significant differences in multivariate analysis. According to NTCP model, the TD5 and TD50 EQD2 dose of sum-dose d1.5cc were 65.26Gy (46.72-80.69Gy) and 125.25Gy (89.51-152.18Gy), respectively. For the accumulated EQD2 dose, the area under ROC shadow was 0.8702 (0.7577-0.9828) in model validation, p<0.001. Conclusion: In this study, a NTCP model of temporal lobe injury after a second course of IMRT for recurrent nasopharyngeal carcinoma was established. TD5 and TD50 doses of temporal lobe injury after re-RT were obtained according to the model, and the model was verified by validation set data.

Axillary Metastasis as the Initial Presentation of Recurrent Nasopharyngeal Carcinoma.

The recurrence of nasopharyngeal carcinoma (NPC) is either at the local primary site or at regional or distant metastases. However, an axillary metastasis is a rare entity in NPC. We highlighted a case of recurrent NPC that presented with axillary swelling as the main initial complaint. Clinical examinations showed enlarged left axillary lymph nodes and left cervical lymph nodes. Histopathological examination of the axillary lymph node biopsy confirmed the recurrence of NPC. The patient underwent palliative chemotherapy in view of the advanced stage of recurrent disease. A thorough clinical history and examination during surveillance are crucial for early diagnosis and better survival outcomes.

Tumor volume instead of recurrent T category predicts clinical outcome of patients with locally recurrent nasopharyngeal carcinoma salvaged by carbon ion radiation therapy.

BACKGROUND: Although carbon ion radiation therapy (CIRT) substantially improves the overall survival (OS) of patients with LR-NPC, approximately 40% of the patients may develop local recurrence. The purpose of study is to assess the value of tumor volume (TV) as a predictive tool to guide individualized CIRT. METHODS: Consecutive patients with LR-NPC treated using CIRT at Shanghai Proton and Heavy Ion Center between April 2015 and May 2019 were included. TV before CIRT was delineated and calculated. The generalized additive Cox model was used to examine the relationship between TV and OS and local progression-free survival (LPFS). A cutoff value of tumor volume was identified to best discriminate patients with different 2-year OS rates, using receiver operating characteristic (ROC) analysis. RESULTS: A total of 157 patients were enrolled. The median tumor volume was 22.49 (2.52-90.13) ml. In the univariable analyses, tumor volume was significantly associated with OS (p < 0.001) and LPFS (p = 0.01). The relationships with OS (p = 0.009) and LPFS (p = 0.020) remained significant in multivariable analyses. Using ROC analysis, a TV of 26.69 ml was identified to predict the 2-year OS rate. To facilitate potential clinical use, 25 ml was designated as the final cutoff value. The 2-year OS and LPFS rates were 88.6 % vs 62.3 %, and 54.7 % vs 35.5 %, for patients with a TV ≤ 25 ml and > 25 ml, respectively. CONCLUSION: Tumor volume could predict the OS and LPFS of patients. We propose that tumor volume should be considered in the risk stratification and CIRT-based treatment for patients with LR-NPC.

A protocol for a randomized trial evaluating the role of carbon-ion radiation therapy plus camrelizumab for patients with locoregionally recurrent nasopharyngeal carcinoma.

PURPOSE: Management of locoregionally recurrent nasopharyngeal carcinoma (LR NPC) is difficult. Although carbon-ion radiation therapy (CIRT) could substantially improve the overall survival (OS) of those patients, around 40% of the patients may still develop local failure. Further improvement of the disease control is necessary. Immunotherapy, such as immune checkpoint inhibitors (ICIs) becomes a promising antitumor treatment. The role of ICIs was proved in head and neck cancers including recurrent/metastatic NPC. Preclinical studies indicated potential synergistic effects between radiation therapy and ICIs. Therefore, we conduct a randomized phase 2 trial to evaluate the efficacy and safety of camrelizumab, an anti-PD-1 monoclonal antibody, along with CIRT in patients with LR NPC. METHODS: Patients will be randomly assigned at 1:1 to receive either standard CIRT with 63 Gy (relatively biological effectiveness, [RBE]) in 21 fractions, or standard CIRT plus concurrent camrelizumab. Camrelizumab will be administered intravenously with a dose of 200 mg, every 2 week, for a maximum of 1 year. We estimate addition of camrelizumab will improve the 2-year progression-free survival (PFS) from 45% to 60%. A total of 146 patients (with a 5% lost to follow-up rate) is required to yield a type I error of 0.2, and a power of 0.8. RESULTS AND CONCLUSION: The results of the trial may shed insights on the combined therapy with ICIs and CIRT.

A novel endoscopic nasopharyngectomy by low-temperature plasma radiofrequency ablation in localized recurrent nasopharyngeal carcinoma.

OBJECTIVE: Endoscopic nasopharyngectomy (ENPG) with en bloc resection has been well accepted in resectable localized recurrent nasopharyngeal carcinoma (rNPC), but it is a difficult technique to master for most otorhinolaryngology head and neck surgeons. Ablation surgery is a new and simplified method to remove tumors. We designed a novel method using low-temperature plasma radiofrequency ablation (LPRA) and evaluated the survival benefit. METHODS: A total of 56 localized rNPC patients were explained in detail and retrospectively analyzed. The surgery method was ablated from the resection margin to the center of the tumor. The postmetastatic overall survival (OS), local relapse-free survival (LRFS) rate, progression-free survival (PFS) and distant metastasis-free survival (DMFS) were analyzed using the Kaplan-Meier method and compared by the log-rank test. RESULTS: All surgeries were successfully performed without any severe postoperative complications or deaths. The median operation time of ablation and harvested NSFF respectively were 29 min (range, 15-100 min) and 101 min (range, 30-180 min). The average number of hospital days postoperation was 3 days (range, 2-5 days). All cases (100.0%) had radical ablation with negative resection margins. The nasopharyngeal defects were completely re-epithelialized in 54 (96.4%) patients. As of the data cutoff (September 3, 2023), the median follow-up time was 44.3 months (range, 17.1-52.7 months, 95% CI: 40.4-48.2). The 3-year OS, LRFS, PFS and DMFS of the entire cohort were 92.9% (95% CI: 0.862-0.996), 89.3% (95% CI: 0.813-0.973), 87.5% (95% CI: 0.789-0.961), and 92.9% (95% CI: 0.862-0.996), respectively. Cycles of radiotherapy were independent risk factors for OS (p = 0.003; HR, 32.041; 95% CI: 3.365-305.064), LRFS (p = 0.002; HR, 10.762; 95% CI: 2.440-47.459), PFS (p = 0.004; HR, 7.457; 95% CI: 1.925-28.877), and DMFS (p = 0.002; HR, 34.776; 95% CI: 3.806-317.799). CONCLUSION: Radical endoscopic nasopharyngectomy by using low-temperature plasma radiofrequency ablation is a novel, safe and simplified method to master and disseminate for treating resectable rNPC. However, further data and longer follow-up time are needed to prove its efficacy.

Preliminary evidence for endoscopic surgery combined with postoperative anti-PD-1 immunotherapy in advanced recurrent nasopharyngeal carcinoma.

BACKGROUD: Endoscopic surgery can be used as the main treatment for advanced recurrent nasopharyngeal carcinoma (rNPC). However, there is a huge clinical controversy about the need for consolidated immunotherapy after surgery. METHODS: We performed a retrospective propensity score-matched analysis (1:2) of patients with locally advanced rNPC who underwent endoscopic nasopharyngectomy (ENPG) combined with anti-programmed cell death protein-1 (PD-1) monotherapy or ENPG alone. The survival rate was analyzed by Kaplan-Meier method. The primary endpoint was progression-free survival (PFS). The secondary endpoints included overall survival (OS), objective response rate (ORR) and disease control rate (DCR). Potential surgical-related complications and immune-related adverse events (AEs) were also assessed. RESULTS: We recruited 10 patients receiving ENPG plus anti-PD-1 monotherapy and 20 receiving ENPG alone. During the mean follow-up of 23.8 months, a significant improvement in the 2-year PFS was detected in the consolidation immunotherapy group compared to the ENPG alone group (80.0% vs. 40.0%; HR = 0.258; 95% CI: 0.09-0.72; p = 0.04), while the 2-year OS in the consolidation immunotherapy group was not significantly longer than that in the ENPG alone group (90.0% vs. 75.0%; HR = 0.482; 95% CI: 0.08-3.00; p = 0.50). The incidence of surgical-related complications in the consolidation immunotherapy group and ENPG alone group was 70.0 and 60.0%, respectively. Immune-related AEs were similar between the toripalimab arm (75.0%) and the camrelizumab arm (66.7%). Surgical-related complications depend on symptomatic treatments. Immune-related AEs were mild and tolerable. CONCLUSIONS: Consolidation immunotherapy regimen for patients with advanced rNPC after ENPG compared to ENPG alone provides a superior PFS rate with a manageable safety profile.

Radiomic signatures reveal multiscale intratumor heterogeneity associated with tissue tolerance and survival in re-irradiated nasopharyngeal carcinoma: a multicenter study.

BACKGROUND: Post-radiation nasopharyngeal necrosis (PRNN) is a severe adverse event following re-radiotherapy for patients with locally recurrent nasopharyngeal carcinoma (LRNPC) and associated with decreased survival. Biological heterogeneity in recurrent tumors contributes to the different risks of PRNN. Radiomics can be used to mine high-throughput non-invasive image features to predict clinical outcomes and capture underlying biological functions. We aimed to develop a radiogenomic signature for the pre-treatment prediction of PRNN to guide re-radiotherapy in patients with LRNPC. METHODS: This multicenter study included 761 re-irradiated patients with LRNPC at four centers in NPC endemic area and divided them into training, internal validation, and external validation cohorts. We built a machine learning (random forest) radiomic signature based on the pre-treatment multiparametric magnetic resonance images for predicting PRNN following re-radiotherapy. We comprehensively assessed the performance of the radiomic signature. Transcriptomic sequencing and gene set enrichment analyses were conducted to identify the associated biological processes. RESULTS: The radiomic signature showed discrimination of 1-year PRNN in the training, internal validation, and external validation cohorts (area under the curve (AUC) 0.713-0.756). Stratified by a cutoff score of 0.735, patients with high-risk signature had higher incidences of PRNN than patients with low-risk signature (1-year PRNN rates 42.2-62.5% vs. 16.3-18.8%, P < 0.001). The signature significantly outperformed the clinical model (P < 0.05) and was generalizable across different centers, imaging parameters, and patient subgroups. The radiomic signature had prognostic value concerning its correlation with PRNN-related deaths (hazard ratio (HR) 3.07-6.75, P < 0.001) and all causes of deaths (HR 1.53-2.30, P < 0.01). Radiogenomics analyses revealed associations between the radiomic signature and signaling pathways involved in tissue fibrosis and vascularity. CONCLUSIONS: We present a radiomic signature for the individualized risk assessment of PRNN following re-radiotherapy, which may serve as a noninvasive radio-biomarker of radiation injury-associated processes and a useful clinical tool to personalize treatment recommendations for patients with LANPC.

c-Met is a chimeric antigen receptor T-cell target for treating recurrent nasopharyngeal carcinoma.

BACKGROUND AIMS: Radiation therapy is the standard treatment for patients with nasopharyngeal carcinoma (NPC), but relapse occurs in 10% to 20% of patients. The treatment of recurrent nasopharyngeal carcinoma (rNPC) remains challenging. Chimeric antigen receptors (CAR)-T-cell therapy has achieved good outcomes in the treatment of leukemia and seems to be a promising therapeutic strategy for solid tumors. c-Met has been found to be highly expressed in multiple cancer types, and the activation of c-Met leads to the proliferation and metastasis of cancer cells. However, the expression of c-Met in rNPC tissues and whether it can be used as a target for CAR-T therapy in rNPC remain to be investigated. METHODS: We detected the expression of c-Met in 24 primary human rNPC tissues and three NPC cell lines and constructed two different antibody-derived anti-c-Met CARs, namely, Ab928z and Ab1028z. To estimate the function of these two different c-Met-targeted CAR-T cells, CD69 expression, cytotoxicity and cytokine secretion of CAR-T cells were assessed after coculture with target cells. A cell line-derived xenograft mouse model also was used to evaluate these two anti-c-Met CAR-T cells. Furthermore, we determined whether combination with an anti-EGFR antibody could promote the antitumor effect of CAR-T cells in a patient-derived xenograft mouse model. RESULTS: High c-Met expression was detected in 23 of 24 primary human rNPC tissues by immunohistochemistry staining and in three NPC cell lines by flow cytometry. Ab928z-T cells and Ab1028z-T cells showed significantly upregulated expression of CD69 after coculture with targeted cells. However, Ab1028z-T cells showed superior cytokine secretion and antitumor activity. Furthermore, Ab1028z-T cells effectively suppressed tumor growth compared with control CAR-T cells, and the combination with nimotuzumab further enhanced the tumor-clearing ability of Ab1028z-T cells. CONCLUSIONS: We found that c-Met is highly expressed in rNPC tissues and confirmed its potential as a CAR-T target for rNPC. Our study provides a new idea for the clinical treatment of rNPC.

Effect of anlotinib combined with ticeorgio for recurrent nasopharyngeal carcinoma: a case report.

For patients with locally unresectable recurrent nasopharyngeal carcinoma who relapsed after 2 years of radiotherapy, re-radiotherapy is also the preferred treatment. However, for patients relapsed within 2 years, the use of re-radiotherapy would be greatly limited by its adverse effects. Consequently, finding a new strategy to prolong the time of re-radiotherapy for locally recurrent nasopharyngeal carcinoma is very necessary to reduce the related side effects and improve the curative effect. Anlotinib is an orally available small molecule multi-target tyrosine kinase inhibitor that primarily inhibits VEGFR2/3, FGFR1-4, PDGFR α/ß, c-Kit, and Ret. However, whether recurrent nasopharyngeal carcinoma patients can be treated with anlotinib combined with ticeorgio (also called S-1) remains unknown. Herein, we report a nasopharyngeal carcinoma patient with local recurrence after radical radiotherapy who benefited from combination treatment of anlotinib with ticeorgio.

Expression and Prognostic Value of Lgr5 in Patients with Recurrent Nasopharyngeal Carcinoma.

Background: As a cancer stem cells (CSCs) surface marker, Lgr5 plays an important role in the signal transduction of cancer cells and is a potential biomarker for cancer diagnosis and prognosis. However, the expression and prognostic value of Lgr5 in recurrent nasopharyngeal carcinoma (rNPC) remains ambiguous. Materials: We used RNA sequencing to screen differentially expressed mRNAs in eleven specimens of rNPC tissues and five fresh adjacent normal tissue samples and the CSC marker, Lgr5, was identified. The expression level of Lgr5 in rNPC samples was also detected by immunohistochemistry and Western blot assay. The chi-square test was used to analyze the relationship between the clinicopathological variables and the immunostaining of Lgr5. The Log-rank method was used for prognosis analysis. The Cox regression model was used for univariate and multivariate analysis. Results: Significantly elevated expression of Lgr5 in the rNPC tissues was observed compared to the normal tissues using RNA sequencing, Western blot and immunohistochemistry. The expression of Lgr5 was significantly correlated with the T stage (P=0.014). High Lgr5 expression (P=0.007), tumor necrosis (P=0.013) and WHO type II (P=0.043) in rNPC patients exhibited worse overall survival (OS). Lgr5 expression was proved to be an independent risk factor for OS (P=0.035) in multivariate analyses, and had promising predictive value for survival and recurrence in rNPC patients (area under the ROC curve: 0.711 and 0.665, P=0.017 and 0.028, respectively). Conclusion: Lgr5 as a CSC marker is a promising therapeutic target and could be employed to predict the survival prognosis of rNPC patients.

Robotic stereotactic body radiotherapy for recurrent nasopharyngeal carcinoma.

Background: We aimed to evaluate the outcomes of patients reirradiated with stereotactic body radiotherapy for recurrent nasopharyngeal carcinoma (r-NPC) in our hospital. Methods: We retrospectively analyzed 10 patients with r-NPC previously irradiated with definitive radiotherapy. Local recurrences were irradiated with a dose of 25 to 50 Gy (median: 26.25 Gy) in 3 to 5 fractions (fr) (median: 5 fr). The survival outcomes calculated from the time of recurrence diagnosis were obtained using Kaplan-Meier analysis and compared with the log-rank test. Toxicities were assessed by using Common Terminology Criteria for Adverse Events Version 5.0. Results: The median age was 55 years (37-79 years), and nine patients were men. The median follow-up was 26 months (3-65 months) after reirradiation. The median overall survival (OS) was 40 months, OS in 1 and 3 years were 80% and 57%, respectively. OS rate of rT4 (n = 5, 50%) was worse compared with rT1, rT2, and rT3 (P = 0.040). In addition, those with less than 24 months of interval between first treatment and recurrence had worse OS (P = 0.017). One patient exhibited Grade 3 toxicity. There is no other Grade ≥3 acute or late toxicities. Conclusion: In r-NPC, reirradiation is inevitable for patients who are not suitable for radical surgical resection. However, serious complications and side effects prevent dose escalation due to the critical structures previously irradiated. Prospective studies with a large number of patients are required to find the optimal acceptable dose.

Identifying the prognostic value of MRI-based tumor response and predicting the risk of radio-resistance in re-radiotherapy for locally recurrent nasopharyngeal carcinoma.

OBJECTIVE: To investigate the prognostic value of tumor response (TR) for locoregionally recurrent nasopharyngeal carcinoma (lrNPC) patients at the end of re-radiotherapy (re-RT) and develop a risk score model to predict patient's radiosensitivity to re-RT. MATERIALS AND METHODS: A total of 594 patients with lrNPC from 2010 to 2020 were retrospectively reviewed as the total cohort. Among these, 310 patients with complete first-line treatment data were reviewed as a secondary cohort. Overall survival (OS) was the primary endpoint. Locoregional control (LRC) was the secondary endpoint. Multivariate Cox analysis was performed to investigate the prognostic value of TR at the end of re-RT (rTR). A risk score model for predicting rTR was obtained by logistic regression analysis, and its effectiveness was compared using receiver operating characteristic (ROC) analysis. RESULTS: Patients with complete response (CR) to rTR had higher 5-year OS and LRC rate than non-CR patients in both the total and secondary cohort. rTR was an independent prognostic factor for OS (P = 0.002) and LRC (P = 0.008). We developed a risk score model including four significant risk factors (relapse T stage, relapse gross tumor volume, time to recurrence, and initial TR). The area under the curve of the risk score model was 0.73 (95% CI: 0.678 to 0.780), which was significantly higher than that of each variable alone. Patients with the highest risk scores may be insensitive to re-RT and had a residual tumor risk of 89.9% after rRT. CONCLUSION: rTR was an independent prognostic factor for OS and LRC in lrNPC patients. We developed a risk score model for predicting patients' sensitivity to re-RT to screen for radiosensitive patients. This can serve as a treatment decision-making tool for clinicians.

Efficacy and safety of PLDR-IMRT for the re-irradiation of recurrent NPC: A prospective, single-arm, multicenter trial.

Salvage treatment of locoregionally recurrent nasopharyngeal carcinoma (NPC) requires weighing the benefits of re-irradiation against increased risks of toxicity. Here, we evaluated the outcomes of patients treated with intensity-modulated-based pulsed low-dose-rate radiotherapy (PLDR-IMRT) to enhance the curative effect of salvage treatment and reduce RT-related SAEs. A prospective clinical trial was conducted from March 2018 to March 2020 at multiple institutions. NPC patients who experienced relapse after radical therapy were re-irradiated with a median dose of 60 Gy (50.4-70 Gy)/30 f (28-35 f) using PLDR-IMRT. Thirty-six NPC patients who underwent PLDR-IMRT for locoregional recurrence were identified. With a median follow-up of 26.2 months, the objective response rate (ORR) of the entire cohort was 91.6%. The estimated mPFS duration was 28 months (95% CI: 24.9-31.1), and the estimated mLRFS duration was 30.4 months (95% CI: 25.2-35.5). The overall survival (OS) rate for all patients was 80.6%, the progression-free survival (PFS) rate was 75% and the cancer-specific survival (CSS) rate was 88.9% at 1 year. The LRFS and DMFS rates were 88.9% and 91.7%, respectively, at 1 year. A combination of systematic therapies could provide survival benefits to patients who experience NPC relapse (p < 0.05), and a Karnofsky performance status (KPS) score of ≥90 was a favorable factor for local control (p < 0.05). The incidence of acute SAEs (grade 3+) from PLDR was 22.2%, and the incidence of chronic SAEs was 19.4% among all patients. PLDR-IMRT combined with systematic therapy can effectively treat patients with locoregionally recurrent nasopharyngeal carcinoma and causes fewer adverse events than the rates expected with IMRT.

Salvage treatments for locally recurrent nasopharyngeal cancer: Systematic review and meta-analysis.

The present study aimed to evaluate the effectiveness and safety of various salvage treatments to treat locally recurrent nasopharyngeal carcinoma (IrNPC). A comprehensive search was conducted to gather relevant research publications on salvage treatment for IrNPC. Specifically, 2-, 3-, and 5-year overall survival were the primary outcome. A total of 89 studies with 101 cohorts were collected. Endoscopic nasopharyngectomy was found to be associated with a significantly improved 5-year OS compared with CRT (p = 0.027) and IMRT (p = 0.016). Moreover, based on recurrence T classification, the 2-, 3-, and 5-year OS were similar across different treatments. Endoscopic nasopharyngectomy was associated with a significant reduction in treatment-related complications (grade ≥ 3) compared with IMRT (p < 0.001) and open nasopharyngectomy (p = 0.028). Endoscopic nasopharyngectomy may provide comparable treatment outcomes to re-irradiation, while offering a better safety profile for selective patients with resectable IrNPC.

Benefit of [18F] FDG PET/CT in the diagnosis and salvage treatment of recurrent nasopharyngeal carcinoma.

PURPOSE: To compare PET/CT, MRI and ultrasonography in detecting recurrence of nasopharyngeal carcinoma and identify their benefit in staging, contouring and overall survival (OS). METHODS: Cohort A included 1453 patients with or without histopathology-confirmed local recurrence, while cohort B consisted of 316 patients with 606 histopathology-confirmed lymph nodes to compare the sensitivities and specificities of PET/CT, MRI and ultrasonography using McNemar test. Cohorts C and D consisted of 273 patients from cohort A and 267 patients from cohort B, respectively, to compare the distribution of PET/CT-based and MRI-based rT-stage and rN-stage and the accuracy of rN-stage using McNemar test. Cohort E included 30 random patients from cohort A to evaluate the changes in contouring with or without PET/CT by related-samples T test or Wilcoxon rank test. The OS of 61 rT3-4N0M0 patients staged by PET/CT plus MRI (cohort F) and 67 MRI-staged rT3-4N0M0 patients (cohort G) who underwent similar salvage treatment were compared by log-rank test and Cox regression. RESULTS: PET/CT had similar specificity to MRI but higher sensitivity (93.9% vs. 79.3%, P < 0.001) in detecting local recurrence. PET/CT, MRI and ultrasonography had comparable specificities, but PET/CT had greater sensitivity than MRI (90.9% vs. 67.6%, P < 0.001) and similar sensitivity to ultrasonography in diagnosing lymph nodes. According to PET/CT, more patients were staged rT3-4 (82.8% vs. 68.1%, P < 0.001) or rN + (89.9% vs. 69.3%, P < 0.001), and the rN-stage was more accurate (90.6% vs. 73.8%, P < 0.001). Accordingly, the contours of local recurrence were more precise (median Dice similarity coefficient 0.41 vs. 0.62, P < 0.001) when aided by PET/CT plus MRI. Patients staged by PET/CT plus MRI had a higher 3-year OS than patients staged by MRI alone (85.5% vs. 60.4%, P = 0.006; adjusted HR = 0.34, P = 0.005). CONCLUSION: PET/CT more accurately detected and staged recurrence of nasopharyngeal carcinoma and accordingly complemented MRI, providing benefit in contouring and OS.

Transoral robotic resection of advanced recurrent nasopharyngeal carcinoma involving the internal carotid artery.

BACKGROUND: Transoral robotic surgery (TORS) is a reliable, minimally invasive approach for treating recurrent nasopharyngeal carcinoma (rNPC). However, tumours involving the internal carotid artery (ICA) are considered to be unsuitable for TORS. This paper presents the first case of transoral robotic resection of advanced rNPC involving the ICA. MATERIALS AND METHODS: This case is a 55 year-old male patient who received radiotherapy 27 years ago. This patient underwent a standard TORS resection 2 weeks after ipsilateral ICA embolization. RESULTS: Postoperative Magnetic resonance imaging and biopsy results indicated total resection. During the 2 month follow-up, no severe complications were found, and the primary site was tumour-free. CONCLUSION: This study preliminarily presents the feasibility and efficiency of advanced rNPC resection with TORS. TORS can potentially provide better quality of life for patients as a less invasive approach than current endoscopic surgery. Even so, the surgical approach should be selected strictly according to the tumour's location.

Development of a normal tissue complication probability (NTCP) model using an artificial neural network for radiation-induced necrosis after carbon ion re-irradiation in locally recurrent nasopharyngeal carcinoma.

Background: The aim of the present study was to build a normal tissue complication probability (NTCP) model using an artificial neural network (ANN) for radiation-induced necrosis after carbon ion re-irradiation in locally recurrent nasopharyngeal carcinoma (rNPC), and to determine the predictive parameters applied to the model. Methods: A total of 150 patients with rNPC treated at Shanghai Proton and Heavy Ion Center during 2015-2019 were selected to determine the dominant factors causing mucosal necrosis after carbon therapy. An ANN was built to study both dose-volume histogram (DVH) and clinical factors. Simple oversampling and data normalization were used in the training process. Ten-fold cross validation was conducted to prevent overfitting. Results: Of the DVH factors, the prediction accuracy ranged from 58.3-65.2%, whereas planning target volume (PTV) receiving dose more than 25 GyE (PTV.V25) yielded the best prediction accuracy. Of the clinical factors, baseline necrosis, sex, and biologically equivalent dose (BED) of initial treatment could increase the accuracy of PTV.V25 by 0.5%, 0.5%, and 1.5%, respectively. Conclusions: An ANN was built to predict radiation-induced necrosis after re-irradiation in rNPC. The best accuracy and area under receiver-operating characteristic (ROC) curve (AUC) were 66.7% and 0.689. The most predictive dosimetric and clinical parameters were PTV.V25 and BED of initial treatment.