Predicting distant metastasis in nasopharyngeal carcinoma using gradient boosting tree model based on detailed magnetic resonance imaging reports

BACKGROUND Development of distant metastasis(DM)is a major concern during treatment of nasopharyngeal carcinoma(NPC).However,studies have demonstrated im-proved distant control and survival in patients with advanced NPC with the addition of chemotherapy to concomitant chemoradiotherapy.Therefore,precise prediction of metastasis in patients with NPC is crucial.AIM To develop a predictive model for metastasis in NPC using detailed magnetic resonance imaging(MRI)reports.METHODS This retrospective study included 792 patients with non-distant metastatic NPC.A total of 469 imaging variables were obtained from detailed MRI reports.Data were stratified and randomly split into training(50%)and testing sets.Gradient boosting tree(GBT)models were built and used to select variables for predicting DM.A full model comprising all variables and a reduced model with the top-five variables were built.Model performance was assessed by area under the curve(AUC).RESULTS Among the 792 patients,94 developed DM during follow-up.The number of metastatic cervical nodes(30.9%),tumor invasion in the posterior half of the nasal cavity(9.7%),two sides of the pharyngeal recess(6.2%),tubal torus(3.3%),and single side of the parapharyngeal space(2.7%)were the top-five contributors for predicting DM,based on their relative importance in GBT models.The testing AUC of the full model was 0.75(95%confidence interval[CI]:0.69-0.82).The testing AUC of the reduced model was 0.75(95%CI:0.68-0.82).For the whole dataset,the full(AUC=0.76,95%CI:0.72-0.82)and reduced models(AUC=0.76,95%CI:0.71-0.81)outperformed the tumor node-staging system(AUC=0.67,95%CI:0.61-0.73).CONCLUSION The GBT model outperformed the tumor node-staging system in predicting metastasis in NPC.The number of metastatic cervical nodes was identified as the principal contributing variable.

Magnetic resonance imaging staging of nasopharyngeal carcinoma in the head and neck

Magnetic resonance imaging (MRI) is the modality of choice for staging nasopharyngeal carcinoma in the head and neck. This article will review the patterns of primary and nodal spread on MRI with reference to the latest 7th edition of the International Union Against Cancer/American Joint Committee on Cancer staging system.

Hypertrophic adenoids in patients with nasopharyngeal carcinoma:appearance at magnetic resonance imaging before and after treatment

Introduction:Patients with nasopharyngeal carcinoma(NPC) sporadically develop abnormal adenoids.Nasopharyngeal adenoids are usually included in the gross tumor volume(GTV) but may have different therapeutic responses than tumor tissue.Therefore,distinguishing adenoids from tumor tissue may be required for precise and efficient chemoradiotherapy and radiotherapy.We characterized nasopharyngeal adenoids and investigated the therapeutic responses of NPC and nasopharyngeal adenoids using magnetic resonance imaging(MRI).Methods:MRI data from 40 NPC patients with a coexisting adenoid mass before and after treatment were analyzed.The features of the adenoid masses,including location,striped appearance,size,interface,symmetry/asymmetry,and cysts,were evaluated.Treatment response were scored according to the World Health Organization guidelines.Results:A striped appearance was observed in 36 cases before treatment and in all cases after treatment.In these 36 cases,the average GTVs including and excluding the uninvolved adenoids were 19.8 cm^3 and 14.8 cm^3,respectively.The average percentage change after excluding the uninvolved adenoids from the GTV was 31.0%.Stable disease in the adenoids was identified in 27(96.4%) of 28 patients after neoadjuvant chemotherapy,while NPC clearly regressed.Partial adenoid responses were identified in 33(82.5%) of 40 patients at 3 months after chemoradiotherapy or radiotherapy,whereas complete tumor responses were achieved in all patients.Six months after treatment,the adenoids continued to atrophy but did not disappear,and tumor recurrence was not found.Conclusions:Nasopharyngeal adenoids and carcinoma tissue in NPC patients can be distinguished by using MRI and have different responses to chemoradiotherapy and radiotherapy.These findings contribute to better delineating the GTV of NPC,based on which spatially optimized strategies can be developed to render precise and efficient chemoradiotherapy and radiotherapy.Additionally,we observed a clear difference in the responses of these two tissue types to current therapies.This finding may reduce or avoid unnecessary biopsies or overtreatment.

Study of MR image for involvement of paranasal sinuses in 56 cases with nasopharyngeal carcinoma

Objective： The aim of the study was to study the nuclear magnetic resonance image （MRI） feature for involvement of paranasal sinuses in patients with nasopharyngeal carcinoma （NPC）. Methods： The MRI of 56 patients with NPC and paranasal sinuses infringed were evaluated between December 2003 and August 2004. Results： Among them, 56 （100%） showed breakage in the wall of paranasal sinuses, 29 （51.8%） had thick mucous membrane in sinuses, 36 （64.3%） showed tumour invasion sinuses, 55 （98.2%） connected with primary carcinoma with the lesion, and 14 （25%） stored up fluid in si- nuses. On MRI scan technique, the positive ratios of diagnoses were 66.1%, 76.8%, and 98.2% respectively （P 〈 0.000） in the horizontal section, coronal section and sagittal section. And nearly 60% was in the TlWl and T2Wl, but 100% in strengthen scan. Conclusion： The findings of sinuses wall breakage, thick mucous membrane in sinuses, tumour invasion cavity connective mass, and same enhancement signal in MR image may indicate the paranasal sinuses involved by primary turnout. The sagittal section and enhanced MRI scans are helpful to diagnosis.

Magnetic Resonance Imaging of Retropharyngeal Lymphadenopathy in Nasopharyngeal Carcinoma

OBJECTIVE The aim of our study was to document the patterns of RLN spread by using MRI. METHODS The MR images of 294 patients with newly diagnosed NPC were reviewed retrospectively. Criteria for metastatic lymph nodes included： shortest axial diameter, nodal necrosis, extracapsular spread, and a contrast enhancing rim. RESULTS RLN involvement was detected in 190 （64.6%） patients. A significantly higher incidence of metastatic RLNs was observed in patients with involvement of the oropharynx, nasal cavity, pre-styloid parapharyngeal space, post-styloid parapharyngeal space, levator muscle of the velum palatini, and tensor muscle of the velum palatine. Patients with level Ⅱ,Ⅲ, and Ⅴ node involvement also had a higher incidence of metastatic RLNs. Of the 231 patients who had metastatic RLNs or cervical lymph nodes, 43 （18.6%） had only metastatic RLNs, 41 （17.7%） had only metastatic cervical lymph nodes, and 147 （63.6%） exhibited an involvement of both the RLNs and cervical lymph nodes. The difference between the incidence of RLN involvements （82.3%） and the incidence of cervical lymph node involvement （81.4%） was very small. CONCLUSION Metastatic RLNs are significantly associated with early stage primary tumor involvement and supper cervical lymph node metastasis in NPC.

Comparing Gross Tumor Volume of Delineation between CT and MRI for Nasopharyngeal Carcinoma

Objective: To study the accuracy between CT and MRI in delineating gross tumor volume (GTV) of nasopharyngeal carcinoma (NPC) in making radiotherapy plan. Methods: The clinical data of 39 cases pathologically proven as nasopharyngeal carcinoma selected from April 2003 to September 2004 were retrospectively analyzed. All were subjected to CT and MR examination one week before treatment. CT scanning was performed with GE Light speed 16, and axial scan was parallel to the OM line routinely from soft palate to the suprasellar cistern. MR scanning was performed by GE Signa super-conducting magnetic resonance imaging system (1.5 Tesla). The standard quadrature head coil was used. Routine axial, sagittal and coronal image with SE sequence were obtained, and FLAIR was used in 10 of 21 cases. Scanned field ranged from the soft palate to the suprasellar cistern. Part of all cases underwent enhanced scanned with Ultravist in CT group or/and GD-DTPA in MR group. All data were analyzed by using the paired-samples t test. Results: The media primary tumor volume (cm3) in CT group and MR group was 32.49±19.91, 29.06±18.75, respectively, and the difference between the two groups were significant (t=5.268, P=0.000). There was significant difference between the two groups in early stage (T1+T2) and advanced stage (T3+T4) by Fuzhou Staging System (t=5.677, P=0.000; t=3.310, P=0.005, respectively). There was significant difference in stage T1, T2, T3 (P=0.005, P=0.001, P=0.004, respectively), and not in stage T4 (P=0.146) between the two groups. Conclusion: MR was more accurate than CT in delineating GTV of NPC, so, is more valuable in making radiotherapy plan.

Significant value of 18F-FDG-PET/CT in diagnosing small cervical lymph node metastases in patients with nasopharyngeal carcinoma treated with intensity-modulated radiotherapy

Background: Little is known about the nature of metaistasis to small cervical lymph nodes(SCLNS) in the patients with nasopharyngeal carcinoma(NPC)examined by using 18-fluoro-2-deoxy-glucose(^(18)F-FDG) positron emission tomography/computed tomography(PET/CT).The present study aimed to evaluate the diagnostic values of PET/CT in identifying metastasis in SCLNs in NPC patients.Methods: Magnetic resonance images(MRI) and PET/CT scans for 470 patients with newly diagnosed, non-distant metastatic NPC were analyzed. Metastatic rates of SCLNs were defined by the positive number of SCLNs on PET/CT scans and total number of SCLNs on MRI scans. Receiver operating characteristic curve was applied to compare PET/CT-determined stage with MRI-determined stage.Results: In total, 2082 SCLNs were identified, with 808(38.8%) ≥ 5 and < 6 mm in diameter(group A), 526(25.3%)≥ 6 and < 7 mm in diameter(group B),374(18.0%)≥ 7 and < 8 mm in diameter(group C), 237(11.4%) ≥8 and<9 mm in diameter(group D),and 137(6.5%) ≥ 9 and <10 mm in diameter(group E).The overall metastatic rates examined by using PET/CT for groups A, B,C,D, and E were 3.5%, 8.0%, 31.3%, 60.0%, and 83.9%, respectively(P< 0.001). In level IV/Vb, the metastatic rate for nodes ≥ 8 mm was 84.6%. PET/CT examination resulted in modification of N category and overall stage for 135(28.7%) and 46(9.8%) patients, respectively. The areas under curve of MRIdetermined and PET/CT-determined overall stage were 0.659 and 0.704 for predicting overall survival, 0.661 and 0.711 for predicting distant metastasis-free survival, and 0.636 and 0.663 for predicting disease-free survival.Conclusions: PET/CT was more effective than MRI in identifying metastatic SCLNs, and the radiologic diagnostic criteria for metastatic lymph nodes in level IV/Vb should be re-defined.

Clinical findings and imaging features of 67 nasopharyngeal carcinoma patients with postradiation nasopharyngeal necrosis

Postradiation nasopharyngeal necrosis is an important late effect of radiotherapy that affects prognosis in patients with nasopharyngeal carcinoma.In the present study,we reviewed the clinical and imaging features of 67 patients with pathologically diagnosed postradiation nasopharyngeal necrosis who were treated at Sun Yat-sen University Cancer Center between June 2006 and January 2010.Their clinical manifestations,endoscopic findings,and imaging features were analyzed.Early nasopharyngeal necrosis was limited to a local site in the nasopharyngeal region,and the tissue defect was not obvious,whereas deep parapharyngeal ulcer or signs of osteoradionecrosis in the basilar region was observed in serious cases.Those with osteoradionecrosis and/or exposed carotid artery had a high mortality.In conclusion,Postradiation nasopharyngeal necrosis has characteristic magnetic resonance imaging appearances,which associate well with clinical findings,but pathologic examination is essential to make the diagnosis.

Clinical-radiological-pathological correlation of cavernous sinus hemangioma: Incremental value of diffusion-weighted imaging

AIMTo elucidate the clinical, magnetic resonance imaging (MRI), pathological features of these lesions and asses the incremental value of diffusion-weighted imaging (DWI) in diagnosing them. METHODSFifteen consecutive patients (11 females and 4 males; mean age 40.93 years; age range 13-63 years) with cavernous sinus hemangiomas (CSH) who underwent examination between November 2008 and May 2016 were included for the analysis. MRI, clinical and surgical findings of each patient was retrospectively reviewed. DWI were also analysed and mean-apparent diffusion coefficient (ADC) value was calculated. Eleven patients underwent surgical removal of the lesion and 2 patients had biopsy only. Diagnosis of CSH was confirmed histologically in 13 patients. RESULTSEleven patients (73%) presented with headaches and 10 (66%) had cranial nerve involvement. Extra cavernous sinus extension was noted in 14 (94%). Surgery was performed in 13 (87%) and post-operative radiation was given to 4 (28%) patients. Thirteen patients remained asymptomatic on follow up. Three conspicuous imaging features were highly suggestive of the diagnosis: Lack of diffusion restriction (100%), homogeneous hyperintensity on T2 weighted image sequences (93.3%) and intense post-contrast enhancement (100%). The mean ADC was 1.82 × 10-3 ± 0.2186 cm2/s. CONCLUSIONT1-weighted hypointensity with homogeneous hyperintensity on T2-weighted sequences, intense enhancement and absence of hemosiderin within the lesion on GRE sequence favour the diagnosis. Facilitated diffusion on DWI differentiates CSH from other solid cavernous sinus lesions and significantly improves the diagnostic accuracy, a critical factor for planning surgery.

Locoregional extension patterns of nasopharyngeal carcinoma and suggestions for clinical target volume delineation

Clinical target volume (CTV) delineation is crucial for tumor control and normal tissue protection. This study aimed to define the locoregional extension patterns of nasopharyngeal carcinoma (NPC) and to improve CTV delineation. Magnetic resonance imaging scans of 2366 newly diagnosed NPC patients were reviewed. According to incidence rates of tumor invasion, the anatomic sites surrounding the nasopharynx were classified into high-risk (>30%), medium-risk (5%-30%), and low-risk (<5%) groups. The lymph node (LN) level was determined according to the Radiation Therapy Oncology Group guidelines, which were further categorized into the upper neck (retropharyngeal region and level Ⅱ), middle neck (levels Ⅲ and Va), and lower neck (levels Ⅳ and Vb and the supraclavicular fossa). The high-risk anatomic sites were adjacent to the nasopharynx, whereas those at medium- or low-risk were separated from the nasopharynx. If the high-risk anatomic sites were involved, the rates of tumor invasion into the adjacent medium-risk sites increased; if not, the rates were significantly lower (P < 0.01). Among the 1920 (81.1%) patients with positive LN, the incidence rates of LN metastasis in the upper, middle, and lower neck were 99.6% , 30.2%, and 7.2%, respectively, and skip metastasis happened in only 1.2% of patients. In the 929 patients who had unilateral upper neck involvement, the rates of contralateral middle neck and lower neck involvement were 1.8% and 0.4%, respectively. Thus, local disease spreads stepwise from proximal sites to distal sites, and LN metastasis spreads from the upper neck to the lower neck. Individualized CTV delineation for NPC may be feasible.

Comparison of diagnostic value of PET using 18- fluoro-2-deoxyglucose, CT and MR1 in detecting skull base invasion of nasopharyngeal carcinomas

Objective： We compared positron emission tomography （PET） using 18-fluoro-2-deoxyglucose （FDG）, enhanced computed tomography （CT） and magnetic resonance imaging （MRI） in detecting skull base invasion of nasopharyngeal carcinomas （NPC） and to evaluate the value of these three methods in determining the existence of skull base invasion of nasopharyngeal carcinomas. Methods： The images of enhanced CT, MRI and PET-CT scans, performed at intervals -〈 20 days on 57 NPC patients from July 2004 to February 2007, were selected and reviewed. The endpoints of the comparison were sensitivity, specificity, accuracy, positive predictive value （PPV） and negative predictive value （NPV） of Enhanced CT, MRI and PET-CT, based on histopathologic findings or clinical imaging follow-up for at least 6 months. Results： For detecting skull base invasion of NPC, the sensitivity of enhanced CT, MRI and PET-CT were 68.18%, 84.09%, 97.67% respectively; speci- ficity were 76.92%, 69.23%, 57.14% respectively; accuracy were 70.18%, 80.7%, 87.72% respectively; PPV were 90.9%, 90.24%, 87.5% respectively; NPV were 41.67%, 56.25%, 88.89% respectively. Conclusion： PET-CT has obvious advantages in sensitivity over CT （P 〈 0.05） and MRI, better than the two methods in accuracy and NPV and may be more valuable for new patients in detecting skull base invasion of NPC patients.

Analysis of pathogenic factors of radiation encephalopathy after radiotherapy for nasopharyngeal carcinoma

The authors investigated 242 patients after radiotherapy for nasopharyngeal carcinoma (NC).Of whom 84 developed radiation encephalopathy (REP), the incidence rate(IR) of REP was 34.7%.In various factors associated with REP, the irradiation source, total r

Recurrent nasopharyngeal Carcinoma and post radiation fibrosis: differentiation with enhanced MRI

Magnetic resonance imaging (MRI) was performed in 40 patients with nasopharyngeal carcinoma (NPC) before and after i.v. administration of Cadolinium-DTPA(Gd-DTPA), for evaluating the role of Gd-DTPA-enhanced imaging in the differentiation of recurrent nasopharyngeal carcinoma (PNPC) from post-radiation fibrosis (RF). MRI diagnosis and findings were confirmedby pathology (n=16) and long-term serial MR/CT and clinical follow-up (n=24), including 3 untreated primary NPC cases,20RNPC cases and 17 RF cases. The results indicated that post-contrast T1 weighted imaging exhibited excellent contrast between thelesion and the surrounding tissue, therefore, it was superior to the Pre-conbet T1WI in showing the relationship between lesionsand adjacent tissues, especially for those lesions located submucosally, and the ones with intl’aCndal invasion. All the NPC andRNPC demonstrated mild to moderate enhancement, with the pattern of homogenous masses or patches. Only 5 cases of the RFgroup demonstrated mild enhancement, which was found in 4 of the 5 cases within one year after radiotherapy. Of the 5 cases,4revealed linear-shaped enhancement. The mean value of enhancement percentage showed marked difference between the twogroups (P<0.05), however, some overlapping existed in their mean ± SD. Gd-DTPA enhanced MR imaging could offer importantinformation for differentiating from RF, on the basis of the intensity and pattern characteristics of the enhancement. It couldalso be helpful in separating thickened mucosa or sinus secretion from tumor, and was superior to unenhanced MR imaging in theearly diagnosis of intracranial involvement of NPC.

Optimization of magnetic resonance sequences in lymph node staging of nasopharyngeal carcinoma

Background Detection rate of retropharyngeal lymph node metastasis in patients with nasopharyngeal carcinoma （NPC） needs to be improved. The purpose of this study was to compare three magnetic resonance （MR） sequences for detecting lymph nodes in patients with NPC. Methods Between July 2007 and March 2008, MR staging of pre-treated tumor was conducted on 120 patients with pathologically confirmed NPC. The outcome of three different sequences for MR NPC staging were compared： coronal short T1 inversion recovery （STIR）, axial proton density fat-suppressed （PDWI fs）, and coronal contrast enhanced fast spin echo T1 weighted fat-suppressed （CE FSE TlWl fs）. Nodal classification method （1999） was applied to count the number of retropharyngeal and cervical lymph nodes discovered by each MR sequence. Paired t tests were used for statistical analysis. Results A total of 2575 lymph nodes were found using coronal STIR sequence; 1816 lymph nodes for coronal CE FSE TIWI fs sequence and 2638 lymph nodes for axial PDWl fs sequence. Significant differences existed in the number of lymph nodes detected by axial PDWI fs and coronal CE FSE T1WI fs sequence （paired t test, P 〈0.05）, with the former sequence getting higher numbers. Statistical differences also existed between coronal STIR and coronal CE FSE TlWl fs sequence （paired ttest, P 〈0.05）, with the former sequence getting higher numbers. No significant difference was found between coronal STIR sequence and axial PDWI fs sequence （paired ttest, P 〉0.05）. Conclusions For the detection of retropharyngeal and cervical lymph nodes, coronal STIR sequence and axial PDWI fs sequence have similar performance and both sequences showed better detection than CE FSE TIWI fs sequence. Furthermore, by combining coronal STIR sequence and axial PDWI fs sequence, we can improve the detection of lymph nodes in NPC N-staging before treatment, especially for lymph nodes located in the thoracic entrance.

颈部影像报告和数据系统在MRI诊断早期单纯黏膜型鼻咽癌局部复发中的应用

目的探讨颈部影像报告和数据系统(neck imaging reporting and data systems,NI-RADS)MRI对单纯黏膜型鼻咽癌局部复发(exclusive mucosal local recurrent nasopharyngeal carcinoma,EMLRNPC)与黏膜治疗后改变(mucosal posttreatment changes,MPTC)的诊断价值,尝试为NI-RADS MRI词典中的局灶性黏膜异常建议附加定性扩散加权成像(diffusion-weighted imaging,DWI)标准。材料与方法回顾性分析2015年2月至2023年2月经病理或影像随访确诊的21例EMLRNPC和29例MPTC。先由2名影像医师独立评价MRI表现,进行NI-RADS MRI分类,再进行附加定性DWI标准的改良NI-RADS MRI分类,3个月后,由其中的1名高年资影像医师再次进行分类。采用Cohen’s Kappa检验评估观察者间、观察者内NI-RADS分类一致性。绘制受试者工作特征(receiver operating characteristic,ROC)曲线评价这两种NI-RADS分类对EMLRNPC与MPTC的诊断效能,曲线下面积(area under the curve,AUC)的比较采用DeLong检验。结果NI-RADS MRI、改良NI-RADS MRI的分类观察者间与观察者内一致性为0.69与0.88、0.83与0.96。NI-RADS MRI和改良NI-RADS MRI鉴别诊断ELRNPC与MPTC的AUC、敏感度、特异度为0.845[95%置信区间(confidence interval,CI):0.715~0.932]、100.0%(95%CI:83.9%~100.0%)、69.0%(95%CI:49.2%~84.7%)和0.966(95%CI:0.871~0.997)、100.0%(95%CI:83.9%~100.0%)、93.1%(95%CI:77.2%~99.2%),两种分类的AUC间差异有统计学意义(Z=2.985,P=0.003)。结论NI-RADS MRI与附加定性DWI标准的改良NI-RADS MRI对EMLRNPC与MPTC均具有较高的鉴别诊断价值,改良NI-RADS MRI分类的诊断效能、一致性更高。

MRI检查鼻咽癌放射性颞叶损伤的漏诊原因

目的:放射治疗是鼻咽癌的主要治疗方法,但容易发生放射性颞叶损伤(radiotherapy-induced temporal lobe injury,RTLI)。磁共振成像(magnetic resonance imaging,MRI)检查是鼻咽癌放射治疗后RTLI的主要诊断方法,但容易漏诊。本研究旨在探讨MRI检查鼻咽癌放射治疗后RTLI漏诊的原因。方法:回顾性分析2010年1月至2021年4月在中南大学湘雅医院诊断为鼻咽癌且接受放射治疗患者的临床和MRI资料。由2位放射科医生重新审阅患者放射治疗前、后所有头颈部(包括鼻咽部和颅脑)MRI资料,对首次发现颞叶晚迟发反应型放射性脑损伤的患者作出首次RTLI诊断。若首次诊断鼻咽癌RTLI患者的原始诊断未报告颞叶病变,则定义为漏诊。将首次诊断鼻咽癌RTLI患者分为漏诊组和非漏诊组。比较漏诊组与非漏诊组的一般临床资料和影像学资料,并进一步采用多因素Logistic回归分析MRI漏诊首次RTLI的独立危险因素。结果:共纳入符合要求的鼻咽癌放射治疗后首次诊断为RTLI的患者187例,原始诊断报告漏诊120例,未漏诊67例,首次诊断RTLI的准确率为35.8%,漏诊率为64.2%。漏诊组与未漏诊组在病灶大小、病灶是否仅在内侧颞叶、对侧颞叶有无病灶、有无白质高信号/囊变及出血、MRI检查部位以及有无水抑制反转恢复序列(fluid attenuated inversion recovery,FLAIR)序列方面的差异均有统计学意义(均P<0.05)。多因素Logistic回归分析显示:病灶≤25 mm、病灶无强化、病灶无囊变及出血、病灶仅在内侧颞叶和仅检查鼻咽部MRI是MRI漏诊首次RTLI的独立危险因素(均P<0.05)。结论:MRI首次诊断RTLI的漏诊主要与病灶的大小和部位、病灶的影像学特点及MRI检查部位相关。

鼻咽癌去神经肌肉病变的MRI表现

目的:观察鼻咽癌患者去神经肌肉病变(DML)的MRI表现。方法:回顾性分析本院2010年2月—2022年2月12例鼻咽癌患者DML的临床资料及MRI图像,观察其MR信号变化、病变强化及扩散加权成像等的表现特点。结果:在12例鼻咽癌患者DML中有4例为三叉神经下颌支支配的咀嚼肌出现DML,8例为舌下神经支配的舌肌出现DML。在4例咀嚼肌DML中,2例为肿瘤复发二程放疗后出现,2例为首程放疗后进展出现;8例舌肌DML中有4例为首程放疗后出现,3例为肿瘤复发二程放疗后出现,1例在初诊时出现。在4例咀嚼肌DML中均观察到肌肉萎缩,2例可看到脂肪替代信号,在T_(1)WI呈高信号,另外2例在T_(1)WI呈等信号,没有观察到脂肪替代信号,在T_(2)WI呈不均匀中高信号,DWI也呈高信号,增强后轻到中度强化;在8例舌肌DML中也都看到肌肉萎缩,在T_(1)WI可观察到脂肪替代信号,其中有5例在T_(2)WI及DWI呈等信号,增强后未见明显强化,3例在T_(2)WI及DWI呈高信号,增强后轻到中度的强化。结论:鼻咽癌合并咀嚼肌或舌肌DML较为少见,但其MRI表现具有一定的特征性,识别其MRI的信号表现有助于DML的早期诊断,并与炎症或肿瘤浸润相鉴别。

ASL-MRI对局部晚期鼻咽癌诱导化疗反应及近期疗效的早期预测价值

目的:通过动脉自旋标记磁共振成像(ASL-MRI)监测局部晚期鼻咽癌(LA-NPC)诱导化疗前、后的肿瘤血流量(TBF),探讨ASL-MRI早期预测LA-NPC诱导化疗反应及近期疗效的价值。方法:收集38例初诊LA-NPC患者,于诱导化疗前、后行ASL-MRI,以获得诱导化疗前TBF(Pre-TBF)和诱导化疗后TBF(Post-TBF),并计算诱导化疗前、后的TBF变化值(ΔTBF)及变化率(ΔTBF%)。在诱导化疗后,将完全缓解(CR)和部分缓解(PR)归为反应组,疾病稳定(SD)及疾病进展(PD)归为非反应组。在放疗后3个月评估近期疗效,分为CR组和非CR组(PR、SD及PD)。采用单因素及多因素二分类logistic回归分析TBF参数对诱导化疗效果及近期疗效的影响。采用受试者工作特性(ROC)曲线确定诊断效能。结果:38例患者中诱导化疗反应组23例(60.5%),非反应组15例(39.5%)。放疗后3个月CR组22例(57.9%),非CR组16例(42.1%)。诱导化疗反应组在放疗后3个月的CR率显著高于非反应组(73.9%vs.33.3%,P=0.02)。38例患者Pre-TBF显著高于Post-TBF(Z=4.227,P<0.001)。诱导化疗反应组Pre-TBF、ΔTBF及ΔTBF%显著高于非反应组(均P<0.05);放疗后3个月CR组的Pre-TBF、ΔTBF及ΔTBF%显著高于非CR组(均P<0.05)。多因素二分类logistic回归结果显示,Pre-TBF是诱导化疗效果的独立影响因素(P=0.027),ROC曲线下面积为0.745(P=0.012);T分期及ΔTBF%是近期疗效的独立影响因素(均P<0.05),ΔTBF%的ROC曲线下面积为0.807(P=0.001)。结论:治疗前LA-NPC肿瘤血流高灌注提示更好的疗效,Pre-TBF可以预测LA-NPC诱导化疗效果,ΔTBF%可以预测LA-NPC近期疗效。

DCE-MRI联合磁共振多b值DWI对鼻咽癌的诊断价值及临床意义

目的:分析磁共振动态增强扫描(DCE-MRI)与磁共振多b值扩散加权成像(DWI)联合诊断在鼻咽癌中的价值和临床意义。方法:选取2021年3月-2023年3月经我院病理初诊为鼻咽癌的50例患者为研究对象,所有患者均进行DCE-MRI及磁共振多b值DWI检查,比较肿瘤病灶与对侧翼外肌定量参数,比较不同b值下的ADC值,比较DCE-MRI、磁共振多b值DWI单独及联合诊断的诊断效能。结果:肿瘤病灶容量转移常数(Ktrans)值、速率常数(Kep)值、血管外细胞外间隙容积比(Ve)值均高于对侧翼外肌(P<0.05)。肿瘤病灶在b=800 s/mm^(2)、b=1200 s/mm^(2)的表观弥散系数(ADC)值均小于对侧翼外肌,且b=1200 s/mm^(2)时的ADC值小于b=800 s/mm^(2)(P<0.05)。DCE-MRI、磁共振多b值DWI联合诊断的诊断准确率、灵敏度及特异度均高于单独诊断(P<0.05)。结论:DCE-MRI联合磁共振多b值DWI诊断的价值较高,具有重要的临床应用推广价值。

MRI影像组学在鼻咽癌诊疗中的研究进展

鼻咽癌(NPC)是头颈部肿瘤中常见的恶性肿瘤之一。影像组学通过分析CT、MRI及PET图像的纹理、形状、信号强度分布等,从中获取肿瘤组织高通量的特征,深挖肿瘤内部生物学信息,拓宽了常规医学成像在临床肿瘤学中的应用场景。其中,MRI在软组织分辨率方面具有显著优势,能够清晰地显示鼻咽部的解剖结构、病变范围及对周围组织侵犯情况,是NPC诊断及分期的首选影像学检查方法。本文就MRI影像组学在NPC临床诊疗应用中的现况研究进行综述。