Magnetic resonance imaging-based lymph node radiomics for predicting the metastasis of evaluable lymph nodes in rectal cancer

BACKGROUND Lymph node(LN)staging in rectal cancer(RC)affects treatment decisions and patient prognosis.For radiologists,the traditional preoperative assessment of LN metastasis(LNM)using magnetic resonance imaging(MRI)poses a challenge.AIM To explore the value of a nomogram model that combines Conventional MRI and radiomics features from the LNs of RC in assessing the preoperative metastasis of evaluable LNs.METHODS In this retrospective study,270 LNs(158 nonmetastatic,112 metastatic)were randomly split into training(n=189)and validation sets(n=81).LNs were classified based on pathology-MRI matching.Conventional MRI features[size,shape,margin,T2-weighted imaging(T2WI)appearance,and CE-T1-weighted imaging(T1WI)enhancement]were evaluated.Three radiomics models used 3D features from T1WI and T2WI images.Additionally,a nomogram model combining conventional MRI and radiomics features was developed.The model used univariate analysis and multivariable logistic regression.Evaluation employed the receiver operating characteristic curve,with DeLong test for comparing diagnostic performance.Nomogram performance was assessed using calibration and decision curve analysis.RESULTS The nomogram model outperformed conventional MRI and single radiomics models in evaluating LNM.In the training set,the nomogram model achieved an area under the curve(AUC)of 0.92,which was significantly higher than the AUCs of 0.82(P<0.001)and 0.89(P<0.001)of the conventional MRI and radiomics models,respectively.In the validation set,the nomogram model achieved an AUC of 0.91,significantly surpassing 0.80(P<0.001)and 0.86(P<0.001),respectively.CONCLUSION The nomogram model showed the best performance in predicting metastasis of evaluable LNs.

Nomogram based on multimodal magnetic resonance combined with B7-H3mRNA for preoperative lymph node prediction in esophagus cancer

Accurate preoperative prediction of lymph node metastasis(LNM)in esophageal cancer(EC)patients is of crucial clinical significance for treatment planning and prognosis.AIM To develop a clinical radiomics nomogram that can predict the preoperative lymph node(LN)status in EC patients.METHODS A total of 32 EC patients confirmed by clinical pathology(who underwent surgical treatment)were included.Real-time fluorescent quantitative reverse transcription-polymerase chain reaction was used to detect the expression of B7-H3 mRNA in EC tissue obtained during preoperative gastroscopy,and its correlation with LNM was analyzed.Radiomics features were extracted from multi-modal magnetic resonance imaging of EC using Pyradiomics in Python.Feature extraction,data dimensionality reduction,and feature selection were performed using XGBoost model and leave-one-out cross-validation.Multivariable logistic regression analysis was used to establish the prediction model,which included radiomics features,LN status from computed tomography(CT)reports,and B7-H3 mRNA expression,represented by a radiomics nomogram.Receiver operating characteristic area under the curve(AUC)and decision curve analysis(DCA)were used to evaluate the predictive performance and clinical application value of the model.RESULTS The relative expression of B7-H3 mRNA in EC patients with LNM was higher than in those without metastasis,and the difference was statistically significant(P<0.05).The AUC value in the receiver operating characteristic(ROC)curve was 0.718(95%CI:0.528-0.907),with a sensitivity of 0.733 and specificity of 0.706,indicating good diagnostic performance.The individualized clinical prediction nomogram included radiomics features,LN status from CT reports,and B7-H3 mRNA expression.The ROC curve demonstrated good diagnostic value,with an AUC value of 0.765(95%CI:0.598-0.931),sensitivity of 0.800,and specificity of 0.706.DCA indicated the practical value of the radiomics nomogram in clinical practice.CONCLUSION This study developed a radiomics nomogram that includes radiomics features,LN status from CT reports,and B7-H3 mRNA expression,enabling convenient preoperative individualized prediction of LNM in EC patients.

Discrimination of Metastatic from Non-metastatic Mesorectal Lymph Nodes in Rectal Cancer Using Quantitative Dynamic Contrast-Enhanced Magnetic Resonance Imaging

Preoperative detection of lymph nodes（LNs） metastasis is always highly challenging for radiologists nowadays. The utility of quantitative dynamic contrast-enhanced magnetic resonance imaging（QDCE-MRI） in identifying LNs metastasis is not well understood. In the present study, 59 patients with histologically proven rectal carcinoma underwent preoperative QDCE-MRI. The short axis diameter ratio, long axis diameter ratio, short-to-long axis diameter ratio and QDEC-MRI parameters（Ktrans, Kep, fPV and Ve） values were compared between the non-metastatic（n=44） and metastatic（n=35） LNs groups based on pathological examination. Compared with the non-metastatic group, the metastatic group exhibited significantly higher short axis diameter（7.558±0.668 mm vs. 5.427±0.285 mm）, Ktrans（0.483±0.198 min-1 vs. 0.218±0.116 min^-1） and Ve（0.399±0.118 vs. 0.203±0.096） values（all P〈0.05）. The short-to-long axis diameter ratio, long axis diameter ratio, Kep and fPV values did not show significant differences between the two groups. In conclusion, our results showed that for LNs larger than 5 mm in rectal cancer, there are distinctive differences in the Ktrans and Ve values between the metastatic and non-metastatic LNs, suggesting that QDCE-MRI may be potentially helpful in identifying LNs status.

Diagnostic Power of Diffusion-weighted Magnetic Resonance Imaging for the Presence of Lymph Node Metastasis:A Meta-analysis

Present work was designed to quantitatively evaluate the performance of diffusion-weighted magnetic resonance imaging（DWI） in the diagnosis of the presence of metastasis in lymph nodes（LNs）. Eligible studies were identified from systematical Pub Med and EMBASE searches. Data were extracted. Meta-analyses were performed to generate pooled sensitivity and specificity on the basis of per-node, per-lesion and per-patient, respectively. Fourteen publications（2458 LNs, 404 lesions and 334 patients） were eligible. Per-node basis demonstrated the pooled sensitivity and specificity was 0.82（P〈0.0001） and 0.90（P〈0.0001）, respectively. Per-lesion basis illustrated the pooled sensitivity and specificity was 0.73（P=0.0036） and 0.85（P〈0.0001）, respectively. Per-patient basis indicated the pooled sensitivity and specificity was 0.67（P=0.0909） and 0.86（P〈0.0001）, respectively. In conclusion, DWI has rather a negative predictive value for the diagnosis of LN metastasis presence. The difference of the mean apparent diffusion coefficients between benign and malignant LNs is not yet stable. Therefore, the DWI technique has to be further improved.

SPIO-enhanced magnetic resonance imaging for differentiating metastatic from hyperplastic lymph nodes: A study in rabbits

Objective: To investigate the potential of superparamagnetic iron oxide particles (SPIO) in MR imaging for the differentiation between hyperplastic and metastatic lymph node. Methods: Animal models of malignant lymph node metastasis were established in 6 New-Zealand rabbits by a unilateral intra-muscular injection of VX2 carcinoma cells, and models of hyperplastic lymph nodes were induced in another 6 rabbits by a unilateral intra-muscular injection of egg yolk emulsion. MR images of the lymph nodes were obtained before and 12 h after interstitial injection of SPIO. Image results were analyzed and compared with pathological findings. Results: On unenhanced images, the signal intensity of hyperplastic and metastatic lymph nodes did not differ significantly. After administration of SPIO, the signal intensity of both hyperplastic and metastatic lymph nodes remained unchanged on T1-weighted SE images. On T2-weighted SE images, the signal intensity of hyperplastic lymph nodes decreased heterogeneously, while that of all metastatic ones remained unchanged. On T2-weighted GRE images, the signal intensity of hyperplastic lymph nodes decreased significantly and homogeneously, while that of 4 metastatic ones remained unchanged and that of the rest 2 decreased heterogeneously. Conclusion: SPIO-enhanced MR imaging may enable the differentiation between the hyperplastic and metastatic lymph nodes.

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.

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.

Lymph node imaging in initial staging of prostate cancer:An overview and update

Accurate nodal staging at the time of diagnosis of prostate cancer is crucial in determining a treatment plan for the patient. Pelvic lymph node dissection is the most reliable method, but is less than perfect and has increased morbidity. Cross sectional imaging with computed tomography (CT) and magnetic resonance imaging (MRI) are non-invasive tools that rely on morphologic characteristics such as shape and size of the lymph nodes. However, lymph nodes harboring metastatic disease may be normal sized and non-metastatic lymph nodes may be enlarged due to reactive hyperplasia. The optimal strategy for preoperative staging remains a topic of ongoing research. Advanced imaging techniques to assess lymph nodes in the setting of prostate cancer utilizing novel MRI contrast agents as well as positron emission tomography (PET) tracers have been developed and continue to be studied. Magnetic resonance lymphography utilizing ultra-small super paramagnetic iron oxide has shown promising results in detection of metastatic lymph nodes. Combining MRL with diffusion-weighted imaging may also improve accuracy. Considerable efforts are being made to develop effective PET radiotracers that are performed using hybrid-imaging systems that combine PET with CT or MRI. PET tracers that will be reviewed in this article include [18F]fluoro-D-glucose, sodium [18F]fluoride, [18F]choline, [11C]choline, prostate specific membrane antigen binding ligands, [11C]acetate, [18F]fluciclovine, gastrin releasing peptide receptor ligands, and androgen binding receptors. This article will review these advanced imaging modalities and ability to detect prostate cancer metastasis to lymph nodes. While more research is needed, these novel techniques to image lymph nodes in the setting of prostate cancer show a promising future in improving initial lymph node staging.

EXPERIMENTAL STUDY OF INFLAMMATORY AND METASTATIC LYMPH NODES WITH DIFFUSION WEIGHTED IMAGING ON ANIMAL MODEL: COMPARISON WITH CONVENTIONAL METHODS

Objective To investigate the feasibility of magnetic resonance （MR） diffusion weighted imaging （DWI） in discriminating inflammatory from VX2 carcinoma metastatic lymph nodes in rabbit model. Methods Twenty New Zealand white rabbits were randomly divided into 2 groups. Complete Freund＇s adjuvant was injected into the bilateral dorsal footpads to set up ipsilateral lymphadenitis model （n = 10）, and the other 10 rabbits received a subcutaneous implantation of VX2 tumor cell suspension （1.5×10^7 cells/mL） in both thighs to set up metastatic lymph node model. MR imaging scan covering the popliteal fossa and lilac fossa including short time inversion recovery echo-planar imaging DWI （STIR-EPI-DWI）, Tl-weighted imaging （T1WI） and T2-weighted imaging （T2WI） was performed 2 weeks after injection. T2WI signal intensity （SI）, DWI SI, long/short axial ratio （LSR） and apparent diffusion coefficient （ADC） values of the lymph nodes were evaluated in all cases. Right after MR imaging scan, popliteal and iliac fossa lymph nodes were collected for hematoxylin-eosin staining. Results Totally 33 lymph nodes larger than 5 turn, including 22 inflammatory and 11 metastatic ones, were successfully isolated and taken into pathological analysis. LSR showed no significant difference between the inflammatory and malignant lymph nodes （P 〉 0.05）. Both benign and malignant lymph nodes appeared iso-intense on TlWI and hyperintense on both T2WI and DWI images with an even lower TlWI and higher T2WI SI core at the hilum. Both T2WI and DWI SI showed no significant difference between two pathological groups （P 〉 0.01） in popliteal fossa. The mean ADC value of inflammatory nodes [（1.199±0.281） ×10^-3 mm^2/s] was significantly higher than that of metastatic nodes [（0.858 ± 0.090） ×10^-3 mm^2/s, P 〈 0.01]. On ADC map, a high ADC value central area could be seen in most of the lymph nodes no matter benign or malignant. ADC value gave out the largest area under curve （AUCADC = 0.955） compared with other three indexes （AUCLsR = 0.488; AUCT2WI SI = 0.727; AUCDDWISI = 0.822） and gave the best sensitivity and specificity in lymph node differential diagnosis compared with the other three indexes. Conclusions High quality DWI image can be obtained using STIR-EPI-DWI sequence in rabbit model. DWI is a new promising technique for differentiating inflammatory from metastatic lymph nodes. Compared with routine MR sequence, DWI could provide more useful physiological and functional information for diagnosis.

Utility of diffusion-weighted imaging in the diagnosis of inguinal lymph node metastasis with malignant melanoma

Malignant melanoma is a malignancy of pigmentproducing cells(melanocytes) located predominantly in the skin. Nodal metastases are an adverse prognostic factor compromising long term patient survival. Therefore, accurate detection of regional nodal metastases is required for optimization of treatment. Computed tomography(CT) and magnetic resonance imaging(MRI) remain the primary imaging modalities for regional staging of malignant melanoma. However, both modalities rely on size-related and morphological criteria to differentiate between benign and malignant lymph nodes, decreasing the sensitivity for detection of small metastases. Surgery is the primary mode of therapy for localized cutaneous melanoma. Patients should be followed up for metastases after surgical removal. We report here a case of inguinal lymph node enlargement with a genital vesicular lesion with a history of surgery for malignant melanoma on her thigh two years ago. CT and diffusion weighted-MRI(DW-MRI) were applied for the lymph node identification. DW-MRI revealed malignant lymph nodes due to malignant melanoma metastases correlation with pathological findings.

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.

Comparison of DWI and PET/CT in evaluation of lymph node metastasis in uterine cancer

AIM: To investigate diffusion-weighted imaging (DWI) and positron emission tomography and computed tomography (PET/CT) with Ⅳ contrast for the preoperative evaluation of pelvic lymph node (LN) metastasis in uterine cancer. METHODS: Twenty-five patients with endometrial or cervical cancer who underwent both DWI and PET/CT before pelvic lymphadenectomy were included in this study. For area specific analysis, LNs were divided into eight regions: both common iliac, external iliac, internal iliac areas, and obturator areas. The classification for malignancy on DWI was a focally abnormal signal intensity in a location that corresponded to the LN chains on the T1WI and T2WI. The criterion for malignancy on PET/CT images was increased tracer uptake by the LN.RESULTS: A total of 36 pathologically positive LN areas were found in 9 patients. With DWI, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy for detecting metastatic LNs on an LN area-by-area analysis were 83.3%, 51.2%, 27.3%, 93.3% and 57.0%, respectively, while the corresponding values for PET/CT were 38.9%, 96.3%, 70.0%, 87.8% and 86.0%. Differences in sensitivity, specificity and accuracy were significant (P < 0.0005). CONCLUSION: DWI showed higher sensitivity and lower specificity than PET/CT. Neither DWI nor PET/CT were sufficiently accurate to replace lymphadenectomy.

Comparison of CT and MRI for presurgical characterization of paraaortic lymph nodes in patients with pancreatico-biliary carcinoma

AIM:To determine the accuracy of computed tomography (CT) and magnetic resonance (MR) for presurgical characterization of paraaortic lymph nodes in patients with pancreatico-biliary carcinoma. METHODS:Two radiologists independently evaluated CT and MR imaging of 31 patients who had undergone lymphadenectomy (9 metastatic and 22 non-metastatic paraaortic nodes). Receiver operating characteristic (ROC) curve analysis was performed using a five point scale to compare CT with MRI. To re-define the morphologic features of metastatic nodes, we evaluated CT scans from 70 patients with 23 metastatic paraaortic nodes and 47 non-metastatic ones. The short axis diameter, ratio of the short to long axis, shape, and presence of necrosis were compared between metastatic and non-metastatic nodes by independent samples t-test and Fisher's exact test. P < 0.05 was considered statistically significant. RESULTS:The mean area under the ROC curve for CT (0.732 and 0.646, respectively) was slightly higher than that for MRI (0.725 and 0.598, respectively) without statistical significance (P = 0.940 and 0.716,respectively). The short axis diameter of the metastatic lymph nodes (mean = 9.2 mm) was significantly larger than that of non-metastatic ones (mean = 5.17 mm, P < 0.05). Metastatic nodes had more irregular margins (44.4%) and central necrosis (22.2%) than non-metastatic ones (9% and 0%, respectively), with statistical significance (P < 0.05). CONCLUSION:The accuracy of CT scan for the characterization of paraaortic nodes is not different from that of MRI. A short axis-diameter (> 5.3 mm), irregular margin, and presence of central necrosis are the suggestive morphologic features of metastatic paraaortic nodes.

Chronic hepatitis B:Enlarged perihepatic lymph nodes correlated with hepatic histopathology

AIM:To assess the value of enlarged perihepatic lymph nodes in determining hepatic histopathology for chronic hepatitis B(CHB) by magnetic resonance imaging(MRI).METHODS:Sixty-seven patients who were clinically and histologically diagnosed with CHB and 18 healthy subjects without history of liver disease underwent abdominal MRI.Histological diagnosis and hepatic inflammation(grade 0-4) and fibrosis(stage 0-4) were assessed by a simplified system for scoring in chronic viral hepatitis.The major imaging protocol included an axial breath-hold fat suppressed fast spoiled gradient echo T2-weighted imaging(T2WI),axial breath-trigger fat suppressed fast recovery fast spin echo T2WI,and axial and coronal fast imaging employing steady-state acquisition.Perihepatic lymph nodes larger than 5 mm in shortest diameter were noted.RESULTS:The numbers and size indexes of lymphnodes greater than 5 mm in shortest diameter in hepatic hilum suggested inflammatory activity for subjects with grade 2 or higher,with a high accuracy of diagnosis(the area under the curves > 0.9,P < 0.001).The numbers of lymph nodes were 2 or more with a sensitivity of 87.27%,a specificity of 90.00%,an accuracy of 88.24%,a positive predictive value of 94.12%,and a negative predictive value of 79.41% in patients with grade 2 or higher,and the size indexes were no less than 180 mm 2 with a sensitivity of 83.64%,a specificity of 100%,an accuracy of 89.41%,a positive predictive value of 100%,and a negative predictive value of 76.92%.The numbers and size indexes of lymph nodes were not correlated with hepatic fibrosis.The signal intensity indexes of lymph nodes were no significant correlation with histological grading or staging of liver.CONCLUSION:The numbers and size indexes of enlarged perihepatic lymph nodes for patients with CHB suggest inflammatory activity for subjects with grade 2 or higher.

Determination of Metastatic Axillary Lymph Node in Breast Cancer: Differentiation with Dynamic MRI Examination by Signal Intensity-Time Curves

Purpose: We aimed to evaluate the role of dynamic magnetic resonance imaging (MRI) in the detection of axillary lymph node metastasis based on the signal intensity-time curves. Materials and Methods: The data of 120 patients (benign patients, n = 91;malignant patients, n = 29) who underwent dynamic breast MRI were reviewed. The lymph nodes with the strongest criteria for malignancy (morphological-dynamic properties) were included in the analysis. Signal intensity-time curves were plotted by the software. Results: Of 29 patients with breast cancer, axillary lymph nodes were involved in 21 and not involved in the remaining 8. There was no significant difference between benign and malignant cases in terms of the distributions of Type Ia, Type Ib and Type IV curves (p = 0.12), whereas a significant difference was found between benign and malignant cases in terms of the distributions of Type II and III curves (p Conclusion: On dynamic MRI studies, benign and metastatic lymph nodes display different signal intensity-time curves.

Malignant proliferative ependymoma of the neck with lymph node metastasis:A case report

BACKGROUND Malignant proliferating trichilemmal tumor(MPTT)is an infrequent malignant neoplasm originating from cutaneous appendages,with only a handful of documented cases.This report delineates a unique instance of MPTT situated in the neck,accompanied by lymph node metastasis.A comprehensive exposition of its clinical trajectory and imaging manifestation is presented,aiming to enhance comprehension and management of this atypical ailment.CASE SUMMARY Patient concerns:A 79-year-old male presented with a longstanding right neck mass persisting for over six decades,exhibiting recent enlargement over the past year.Diagnoses:Enhanced magnetic resonance imaging of the neck unveiled an elliptical mass on the right neck side,characterized by an ill-defined border and a heterogeneous signal pattern.The mass exhibited subdued signal intensity on T1-weighted imaging(T1WI)and a heterogeneous high signal on T2-weighted imaging(T2WI),interspersed with a lengthy T1 and T2 cystic signal motif.Close anatomical association with the submandibular gland joint was noted,and intravenous gadolinium diethylene triamine pentaacetic acid administration facilitated conspicuous enhancement.Substantial enhancement of the solid segment prompted an initial preoperative diagnosis of malignant nerve sheath tumor.However,post-surgery histopathological and immunohistochemical analysis conclusively confirmed the diagnosis as malignant hyperplastic external hair root sheath tumor.Intervention:Complete excision of the tumor was successfully executed.Outcomes:The patient experienced a favorable postoperative recovery.CONCLUSION Malignant proliferative trichilemmal tumor external hair root sheath tumor is a cystic-solid lesion,appearing as low signal on T1WI images or high signal on T2WI with enhancement of the solid component.Suspicions of malignancy are heightened when the tumor border is indistinct,tissue planes are breached,or when linear or patchy high signals are observed in the subcutaneous tissue on T1 liver acquisition with volume acceleration enhanced images along with intermediate signal on T2WI and restricted diffusion on diffusion-weighted imaging images.Strong consideration for malignancy should arise if there are signs of compromised adjacent tissue relationships or direct invasion evident on imaging.We have incorporated the above-mentioned content into the entire manuscript.

Computed tomography and magnetic resonance imaging evaluation of pelvic lymph node metastasis in bladder cancer

Background:Accurate evaluation of lymph node metastasis in bladder cancer(BCa)is important for disease staging,treatment selection,and prognosis prediction.In this study,we aimed to evaluate the diagnostic accuracy of com-puted tomography(CT)and magnetic resonance imaging(MRI)for metastatic lymph nodes in BCa and establish criteria of imaging diagnosis.Methods:We retrospectively assessed the imaging characteristics of 191 BCa patients who underwent radical cys-tectomy.The data regarding size,shape,density,and diffusion of the lymph nodes on CT and/or MRI were obtained and analyzed using Kruskal-Wallis test and χ^(2) test.The optimal cutoff value for the size of metastatic node was deter-mined using the receiver operating characteristic(ROC)curve analysis.Results:A total of 184 out of 3317 resected lymph nodes were diagnosed as metastatic lymph nodes.Among 82 imaging-detectable lymph nodes,51 were confirmed to be positive for metastasis.The detection rate of metastatic nodes increased along with more advanced tumor stage(P<0.001).Once the ratio of short-to long-axis diameter≤0.4 or fatty hilum was observed in lymph nodes on imaging,it indicated non-metastases.Besides,lymph nodes with spiculate or obscure margin or necrosis indicated metastases.Furthermore,the short diameter of 6.8 mm was the optimal threshold to diagnose metastatic lymph node,with the area under ROC curve of 0.815.Conclusions:The probability of metastatic nodes significantly increased with more advanced T stages.Once lymph nodes are detected on imaging,the characteristic signs should be paid attention to.The short diameter>6.8 mm may indicate metastatic lymph nodes in BCa.

Kinetically inert manganese(II)-based hybrid micellar complexes for magnetic resonance imaging of lymph node metastasis

The localization and differential diagnosis of the sentinel lymph nodes(SLNs)are particularly important for tumor staging,surgical planning and prognosis.In this work,kinetically inert manganese(II)-based hybrid micellar complexes(MnCs)for magnetic resonance imaging(MRI)were developed using an amphiphilic manganese-based chelate(C18-PhDTA-Mn)with reliable kinetic stability and self-assembled with a series of amphiphilic PEG-C18 polymers of different molecular weights(C18En,n=10,20,50).Among them,the probes composed by 1:10 mass ratio of manganese chelate/C18En had slightly different hydrodynamic particle sizes with similar surface charges as well as considerable relaxivities(∼13 mM^(−1)s^(−1)at 1.5 T).In vivo lymph node imaging in mice revealed that the MnC MnC-20 formed by C18E20 with C18-PhDTA-Mn at a hydrodynamic particle size of 5.5 nm had significant signal intensity brightening effect and shortened T1 relaxation time.At an imaging probe dosage of 125μg Mn/kg,lymph nodes still had significant signal enhancement in 2 h,while there is no obvious signal intensity alteration in non-lymphoid regions.In 4T1 tumor metastatic mice model,SLNs showed less signal enhancement and smaller T1 relaxation time variation at 30 min post-injection,when compared with normal lymph nodes.This was favorable to differentiate normal lymph nodes from SLN under a 3.0-T clinical MRI scanner.In conclusion,the strategy of developing manganese-based MR nanoprobes was useful in lymph node imaging.

多模态磁共振成像评估乳腺癌腋窝淋巴结转移

目的:分析多模态磁共振成像(MRI)在乳腺癌腋窝淋巴结转移(ALNM)评估效果以及可靠指标。方法:选取2020年1月至2021年11月在邯郸市第一医院确诊并接受手术治疗的152例女性乳腺癌患者,根据术后腋窝淋巴结病理结果将其分为ALNM组(45例)和非ALNM组(107例)。利用磁共振动态增强成像(DCE-MRI)、T2加权成像(T2WI)和弥散加权成像(DWI)技术对乳腺癌ALNM做出判定。结果:多模态MRI诊断灵敏度为82.22%,特异度为96.26%,阳性预测值为90.24%,阴性预测值为92.79%,诊断符合率为92.11%。logistic回归分析显示,肿瘤最大径、ADC值与淋巴结转移密切相关。受试者工作特征(ROC)曲线分析,肿瘤最大径ROC曲线下面积(AUC)为0.797(95%CI:0.694~0.842,P<0.01),在最佳截断值为1.96 cm下诊断的灵敏度为77.4%,特异度为60.7%;ADC值AUC为0.844(95%CI:0.808~0.915,P<0.01),在最佳截断值1.122×10^(-3)mm^(2)/s下诊断灵敏度为82.1%,特异度为71.2%。肿瘤最大径和AUC值联合诊断AUC为0.952(95%CI:0.904~0.991,P<0.01),最佳截断值下灵敏度为88.6%,特异度为81.4%。联合指标的AUC要高于肿瘤最大径(Z=3.982,P<0.05)和ADC值(Z=3.014,P<0.05)。结论:多模态MRI对乳腺癌ALNM诊断效果良好,其中肿瘤最大径和AUC值是重要的参考指标,两者联合应用能提高诊断效率。

乳腺癌前哨淋巴结MRI研究进展

无创性方法准确评估乳腺癌前哨淋巴结状态对于避免不必要的外科手术及选择最佳治疗方案具有重要意义。扩散加权成像(DWI)和动态增强MRI(DCE-MRI)等多种MRI技术可为术前评估乳腺癌前哨淋巴结状态提供有价值的信息。就MRI评估乳腺癌前哨淋巴结状态的研究进展进行综述。