Classification of superficial suspected lymph nodes: non-invasive radiomic model based on multiphase contrast-enhanced ultrasound for therapeutic options of lymphadenopathy

Background

Accurate determination of the types of lymphadenopathy is of great importance in disease diagnosis and treatment and is usually confirmed by pathological findings. Radiomics is a non-invasive tool that can extract quantitative information from medical images. Our study was designed to develop a non-invasive radiomic approach based on multiphase contrast-enhanced ultrasound (CEUS) images for the classification of different types of lymphadenopathy.

Methods

A total of 426 patients with superficial suspected lymph nodes (LNs) from three centres were grouped into a training cohort (n=190), an internal testing cohort (n=127), and an external testing cohort (n=109). The radiomic features were extracted from the prevascular phase, vascular phase, and postvascular phase of the CEUS images. Model 1 (the conventional feature model), model 2 (the multiphase radiomics model), and model 3 (the combined feature model) were established for lymphadenopathy classification. The area under the curve (AUC) and confusion matrix were used to evaluate the performance of the three models. The usefulness of the models was assessed in different threshold probabilities by decision curve analysis.

Results

There were 139 patients (32.6%) with benign LNs, 110 patients (25.8%) with lymphoma, and 177 patients (41.5%) with metastatic LNs in our population. Finally, twenty features were selected to construct the radiomics models for these three types of lymphadenopathy. Model 2 integrating multiphase images of the CEUS yielded the AUCs of 0.838, 0.739, and 0.733 in the training cohort, internal testing cohort, and external testing cohort, respectively. After the combination of conventional features and radiomic features, the AUCs of model 3 improved to 0.943, 0.823 and 0.785 in the training cohort, internal testing cohort, and external testing cohort. Besides, model 3 had an accuracy of 81.05%, sensitivity of 80%, and specificity of 90.43% in the training cohort. Model performance was further confirmed in the internal testing cohort and external testing cohort.

Conclusions

We constructed a combined feature model using a series of CEUS images for the classification of the lymphadenopathies. For patients with superficial suspected LNs, this model can help clinicians make a decision on the LN type noninvasively and choose appropriate treatments.

Factors associated with increased diagnostic yield of endobronchial ultrasound-guided transbronchial needle aspiration: an observational single center study

Background

Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is an innovative tool for diagnosing mediastinal diseases. We investigated the factors affecting the diagnostic yield of EBUS-TBNA and evaluated whether the effects of these factors (number of biopsies, core tissue acquisition rate, and diameter and volume of tissue) vary depending on computed tomography (CT) and/or positron emission tomography (PET)/CT results.

Methods

We retrospectively analyzed lung cancer patients who underwent EBUS-TBNA at Korea University Ansan Hospital (January 2019-December 2022). Patients in whom EBUS-TBNA failed and those with missing diameter or volume data and no imaging data interpretation were excluded. Subgroup analysis was performed by dividing the patients into None (no cancer detected on CT or PET/CT), Either (cancer detected on either CT or PET/CT), and Both (cancer detected on both CT and PET/CT) groups.

Results

In all, 228 patients were enrolled; 351 lymph node stations were analyzed. The median age of the patients was 69 years (male, 76.8%). Adenocarcinoma (28.5%) was the most common diagnosis. EBUS-TBNA was predominantly performed at station #4R (30.5%). Each examination involved two stations with a total procedure time of 30 minutes. An increased number of passes led to a higher diagnostic yield for EBUS-TBNA (P<0.001). Additionally, successful tissue sampling was associated with a large diameter (P=0.016) and volume (P=0.002) of the tissue. The effect of these factors was modified by imaging results. In the None and Either groups, an increase in the pass number was correlated with an increased diagnostic yield (adjusted P=0.003 and 0.007, respectively). However, in the Both group, it was not significant and remained at a suggestive level (P=0.304). The diameter and volume did not differ significantly across subgroups (adjusted P>0.05).

Conclusions

Increasing the number of passes during EBUS-TBNA can maximize the diagnostic yield, especially when CT and/or PET/CT results are inconclusive.

Surgical management of breast cancer-related lymphedema: a narrative review of contemporary practices

Background and Objective

Breast cancer-related lymphedema (BCRL) represents a colossal burden in terms of health and patient-reported outcomes. Surgical management plays a prominent role in the psychological and physical well-being of women suffering from BCRL. Therefore, we performed a narrative review of the current surgical management of BCRL and analyzed the postoperative results.

Methods

A literature search was conducted across PubMed MEDLINE, Scopus, and Web of Science from database inception through January 2, 2023. We included English-written studies evaluating postoperative outcomes of lymphatic surgery for the management of BCRL.

Key Content and Findings

The surgical management of lymphedema can be classified into two approaches: (I) physiologic procedures and (II) debulking or ablative procedures. While ablative procedures are intended to lessen the symptomatic burden of lymphedema via the removal of pathological tissues, physiologic procedures are performed to restore the abnormal lymphatic flow by creating bypasses into the venous or lymphatic circulation, or by creating new lymphatic connections by means of lymphangiogenesis. Physiologic procedures generate better outcomes in the early stages of lymphedema as there is some residual physiologic flow and vessels are less fibrotic, while ablative procedures are regarded to be the best alternative in very advanced lymphedema stages. A combination of physiologic and ablative procedures provides more comprehensive surgical management to BCRL.

Conclusions

Lymphedema is a common complication of breast cancer treatment with an extensive incidence range. Postoperative outcomes of the surgical management of BCRL are heterogeneous despite most studies indicating favorable results after lymphatic surgery.

Extracellular ATP Limits Homeostatic T Cell Migration Within Lymph Nodes

Whereas adenosine 5'-triphosphate (ATP) is the major energy source in cells, extracellular ATP (eATP) released from activated/damaged cells is widely thought to represent a potent damage-associated molecular pattern that promotes inflammatory responses. Here, we provide suggestive evidence that eATP is constitutively produced in the uninflamed lymph node (LN) paracortex by naïve T cells responding to C-C chemokine receptor type 7 (CCR7) ligand chemokines. Consistently, eATP was markedly reduced in naïve T cell-depleted LNs, including those of nude mice, CCR7-deficient mice, and mice subjected to the interruption of the afferent lymphatics in local LNs. Stimulation with a CCR7 ligand chemokine, CCL19, induced ATP release from LN cells, which inhibited CCR7-dependent lymphocyte migration in vitro by a mechanism dependent on the purinoreceptor P2X7 (P2X7R), and P2X7R inhibition enhanced T cell retention in LNs in vivo. These results collectively indicate that paracortical eATP is produced by naïve T cells in response to constitutively expressed chemokines, and that eATP negatively regulates CCR7-mediated lymphocyte migration within LNs via a specific subtype of ATP receptor, demonstrating its fine-tuning role in homeostatic cell migration within LNs.

Added value of spectral parameters for the assessment of lymph node metastasis of lung cancer with dual-layer spectral detector computed tomography

Background

Lymph node (LN) metastasis is an important factor affecting the treatment of lung cancer. The purpose of this article was to investigate the benefits of dual-layer spectral detector computed tomography (SDCT) for the evaluation of metastatic LNs in lung cancer.

Methods

Data from 93 patients with lung cancer who underwent dual-phase enhanced scanning with SDCT were retrospectively analyzed. According to the pathological findings, 166 LNs were grouped as metastatic (n=80) or non-metastatic (n=86). LNs in station 4 (n=80) and station 7 (n=35) accounted for the majority of the LNs (approximately 69.23%). The short-axis diameter of the LN, arterial enhancement fraction (AEF), normalized iodine concentration (NIC), and the slope of the spectral Hounsfield unit curve (λ_HU) during the arterial phase (AP) and venous phase (VP) were measured. The Mann-Whitney U test was used to statistically compare these quantitative parameters. Receiver operating characteristic (ROC) curves were plotted to identify the cutoff values, and decision curve analysis (DCA) was performed to determine the net benefit of each parameter. The diagnostic performance, obtained by combining the short-axis diameter with each of the above parameters, was also studied.

Results

The short-axis LN diameter, AEF, NIC, and λ_HU during the AP and VP all showed significant differences between the metastatic and non-metastatic groups (P<0.05). Of the parameters, the AEF had the greatest diagnostic efficiency for metastatic LNs [area under the ROC curve (AUC)_AEF =0.885] with a threshold of 86.40%. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and 95% confidence interval were 90.00%, 89.53%, 88.89%, 90.59%, and 0.830-0.944, respectively. When the quantitative parameters were combined with the short-axis diameter, the AUCs of the parameters, except the AEF, were significantly improved (P<0.05).

Conclusions

The iodine quantitative parameters from SDCT, such as the AEF, demonstrated high diagnostic performances in the differentiation of metastatic and non-metastatic LNs.

A magnetic resonance imaging (MRI)-based nomogram for predicting lymph node metastasis in rectal cancer: a node-for-node comparative study of MRI and histopathology

BACKGROUND

The aim of the present study was to investigate the potential risk factors for lymph node metastasis (LNM) in rectal cancer using magnetic resonance imaging (MRI), and to construct and validate a nomogram to predict its occurrence with node-for-node histopathological validation.

METHODS

Our prediction model was developed between March 2015 and August 2016 using a prospective primary cohort (32 patients, mean age: 57.3 years) that included 324 lymph nodes (LNs) from MR images with node-for-node histopathological validation. We evaluated multiple MRI variables, and a multivariable logistic regression analysis was used to develop the predictive nomogram. The performance of the nomogram was assessed with respect to its calibration, discrimination, and clinical usefulness. The performance of the nomogram in predicting LNM was validated in an independent clinical validation cohort comprising 182 consecutive patients.

RESULTS

The predictors included in the individualized prediction nomogram were chemical shift effect (CSE), nodal border, short-axis diameter of nodes, and minimum distance to rectal cancer or rectal wall. The nomogram showed good discrimination (C-index: 0.947; 95% confidence interval: 0.920-0.974) and good calibration in the primary cohort. Decision curve analysis confirmed the clinical usefulness of the nomogram in predicting the status of each LN. For the prediction of LN status in the clinical validation cohort by readers 1 and 2, the areas under the curves using the nomogram were 0.890 and 0.841, and the areas under the curves of readers using their experience were 0.754 and 0.704, respectively. Diagnostic efficiency was significantly improved by using the nomogram (P<0.001).

CONCLUSIONS

The nomogram, which incorporates CSE, nodal location, short-axis diameter, and minimum distance to rectal cancer or rectal wall, can be conveniently applied in clinical practice to facilitate the prediction of LNM in patients with rectal cancer.

Deep transfer learning based on magnetic resonance imaging can improve the diagnosis of lymph node metastasis in patients with rectal cancer

Background

Lymph node (LN) metastasis is the main prognostic factor for local recurrence and overall survival of patients with rectal cancer. The accurate evaluation of LN status in rectal cancer patients is associated with improved treatment and prognosis. This study aimed to apply deep transfer learning to classify LN status in patients with rectal cancer to improve N staging accuracy.

Methods

The study included 129 patients with 325 rectal cancer screenshots of LN T2-weighted (T2W) images from April 2018 to March 2019. Deep learning was applied through a pre-trained model, Inception-v3, for recognition and detection of LN status. The results were compared to manual identification by experienced radiologists. Two radiologists reviewed images and independently identified their status using various criteria with or without short axial (SA) diameter measurements. The accuracy, positive predictive value (PPV), negative predictive value (NPV), sensitivity, specificity, and the area under the receiver operating characteristic (ROC) curve (AUC) were calculated.

Results

When the same radiologist performed the analysis, the AUC was not significantly different in the presence or absence of LN diameter measurements (P>0.05). In the deep transfer learning method, the PPV, NPV, sensitivity, and specificity were 95.2%, 95.3%, 95.3%, and 95.2%, respectively, and the AUC and accuracy were 0.994 and 95.7%, respectively. These results were all higher than that achieved with manual diagnosis by the radiologists.

Conclusions

The internal details of LNs should be used as the main criteria for positive diagnosis when using MRI. Deep transfer learning can improve the MRI diagnosis of positive LN metastasis in patients with rectal cancer.

Clinical validity of 25-gauge endobronchial ultrasound-guided transbronchial needle in lymph node staging of lung cancer

Background

Endobronchial ultrasound-guided transbronchial needle aspiration is recommended for lymph node (LN) staging in lung cancer. Although 22-gauge needles are widely used, they may make some stations difficult to puncture owing to an acute angle. A thinner 25-gauge needle was introduced in Japan at the end of 2016 and offered structural advantages such as improved flexibility and penetrability. We aimed to validate the clinical utility of the 25-gauge needle in LN staging.

Methods

Patients who underwent endobronchial ultrasound-guided transbronchial needle aspiration for LN staging of lung cancer using the 25-gauge needle at our institution between November 2016 and March 2019 were included. Patient characteristics, staging procedures, pathology findings, and genetic testing success rates were assessed.

Results

Data of 130 patients were included in the analysis. The sampling rate was 87.6% (589/672 lesions). In addition to stations #4R, #7, and #11, which are generally easy to puncture, multiple stations (40.1%) were sampled. The diagnostic accuracy of combined computed tomography and fluorodeoxyglucose positron emission tomography was 82.3% and that of additional endobronchial ultrasound-guided transbronchial needle aspiration was 96.9%. The overall sensitivity, specificity, and positive and negative predictive values validated using resected specimens were 97.1% (34/35), 100% (41/41), 100% (34/34), and 97.6% (41/42), respectively. The success rate of genetic testing was 100% (34/34).

Conclusions

The new 25-gauge needle enabled us to approach a wide range of LNs with a desirable sampling rate and diagnostic accuracy in LN staging using endobronchial ultrasound-guided transbronchial needle aspiration, while providing enough tissue for genetic testing.

Dual-energy computed tomography could reliably differentiate metastatic from non-metastatic lymph nodes of less than 0.5 cm in patients with papillary thyroid carcinoma

Background

Dual-energy computed tomography (DECT) has been widely applied to detect lymph node (LN) and lymph node metastasis (LNM) in various cancers, including papillary thyroid carcinoma (PTC). This study aimed to quantitatively evaluate metastatic cervical lymph nodes (LNs) <0.5 cm in patients with PTC using DECT, which has not been done in previous studies.

Methods

Preoperative DECT data of patients with pathologically confirmed PTC were retrospectively collected and analyzed between May 2016 and June 2018. A total of 359 LNs from 52 patients were included. Diameter, iodine concentration (IC), normalized iodine concentration (NIC), and the slope of the energy spectrum curve (λ_HU) of LNs in the arterial and the venous phases were compared between metastatic and non-metastatic LNs. The optimal parameters were obtained from the receiver operating characteristic (ROC) curves. The generalized estimation equation (GEE) model was used to evaluate independent diagnostic factors for LNM.

Results

A total of 139 metastatic and 220 non-metastatic LNs were analyzed. There were statistical differences of quantitative parameters between the two groups (P value 0.000-0.007). The optimal parameter for diagnosing LNM was IC in the arterial phase, and its area under the curve (AUC), sensitivity, and specificity were 0.775, 71.9%, and 73.6%, respectively. When the three parameters of diameter, IC in the arterial phase, and NIC in the venous phase were combined, the prediction efficiency was better, and the AUC was 0.819. The GEE results showed that LNs located in level VIa [odds ratio (OR) 2.030, 95% confidence interval (CI): 1.134-3.634, P=0.017], VIb (OR 2.836, 95% CI: 1.597-5.038, P=0.000), diameter (OR 2.023, 95% CI: 1.158-3.532, P=0.013), IC in the arterial phase (OR 4.444, 95% CI: 2.808-7.035, P=0.000), and IC in the venous phase (OR 5.387, 95% CI: 3.449-8.413, P=0.000) were independent risk factors for LNM in patients with PTC.

Conclusions

DECT had good diagnostic performance in the differentiation of cervical metastatic LNs <0.5 cm in patients with PTC.

Comparison of cross-sectional imaging techniques for the detection of prostate cancer lymph node metastasis: a critical review

Conventional staging for prostate cancer (PCa) is performed for men diagnosed with unfavorable-intermediate or higher risk disease. Computed tomography (CT) of the abdomen and pelvis and whole body bone scan remains the standard of care for the detection of visceral, nodal, and bone metastasis. The implementation of the 2012 United States Preventive Services Task Force recommendation against routine prostate specific antigen (PSA) screening resulted in a rise of metastatic PCa at the time of diagnosis, emphasizing the importance of effective imaging modalities for evaluating metastatic disease. CT plays a major role in clinical staging at the time of PCa diagnosis, but multi-parametric magnetic resonance imaging (MRI) is now integrated into many prostate biopsy protocols for the detection of primary PCa, and may be a surrogate for CT for nodal staging. Current guidelines incorporate both CT and MRI as appropriate cross-sectional imaging modalities for the identification of nodal metastasis in indicated patients. There is an ongoing debate about the utility of traditional cross-sectional imaging modalities as well as advanced imaging modalities in detection of both organ-confined PCa detection and nodal involvement.

Comparison of four lymph node staging systems for predicting prognosis for stage IV rectum cancer

Background

With recommendation of surgical management in primary site, both the positive and negative lymph nodes (LNs) retrieved have been emphasized to predict prognosis in stage IV rectum cancer. Therefore, we attempt to compare the prognostic performance of American Joint Committee on Cancer (AJCC) N-stage relative to lymph node ratio (LNR), log odds of metastatic lymph nodes (LODDS), and N-score in stage IV rectal cancer.

Methods

Total 5,090 patients taken surgical resection of primary site in rectum cancer with distant metastasis were extracted from Surveillance, Epidemiology, and End Results Program (SEER) database. Harrell's C statistic (C-index) and Akaike's Information Criterion (AIC) were used to evaluate the discriminative ability of the different LN staging systems.

Results

Of the 3,243 patients without radiotherapy, 82.46% (n=2,675) had been found with lymph nodes metastasis with median number of 16 lymph nodes collected (IQR: 11-22). Modeled as categorical cutoff variables for further clinical usage, when number of LNs was between 12 and 25 (C-index: 0.5997, AIC: 1,698.015), 8^th AJCC N-stage outperformed other three schemas with increasing C-index and less AIC value. Assessed as continuous values, the LODDS shown as the best schemas with greatest discriminatory power (C-index: 0.5971, AIC: 3,680.017), generally. On the other hand, in the cohorts of other 1274 patients taken radiation, the median number of lymph nodes retrieved was 13 (IQR: 9-18). LODDS still remained remarkable performance as continuous (C-index: 0.5912; AIC: 1,058.765) and categorical variables (C-index: 0.5700; AIC: 1,061.703), while N-staging outperformed with less than 25 lymph nodes retrieved (LNs <12 C-index: 0.5678, AIC: 481.94; 12< LNs <25 C-index: 0.5933, AIC: 390.395).

Conclusions

When assessed as categorical variables, N-stage performed superiorly with adequate lymph nodes examined, whether the patients have got radiotherapy prior to surgery or not. LODDS showed, when assessed as a continuous variable, good discriminative ability and goodness of fit in predicting survival for stage IV rectum cancer patients regardless of radiation therapy status.

Diffusion-weighted imaging (DWI) in lymph node staging for prostate cancer

In patients with prostate cancer, the presence of lymph node (LN) metastases is a critical prognostic factor and is essential for treatment planning. Conventional cross-sectional imaging performs poorly for nodal staging as both computed tomography (CT) and magnetic resonance imaging (MRI) are mainly dependent on size and basic morphological criteria. Therefore, extended pelvic LN dissection (ePLND) remains the gold standard for LN staging, however, it is an invasive procedure with its own drawbacks, thus creating a need for accurate preoperative imaging test. Incorporating functional MRI by using diffusion-weighted MRI has proven superior to conventional MRI protocol by means of both qualitative and quantitative assessment. Currently, the increased diagnostic performance remains insufficient to replace ePLND and the future role of DWI may be through combination with MR lymphangiography or with novel positron emission tomography (PET) tracers. In this article, the current state of data supporting DWI in LN staging of patients with prostate cancer is discussed.

The self-curing phenomenon of schistosome infection in rhesus macaques: insight from in vitro studies

A reduction in the burden of schistosomiasis is potentially achievable by integrating a schistosomiasis vaccine with current control measures. Here, we determine parasite-specific in vitro responses of B, T, and NK cells from naive uninfected rhesus macaques to Schistosoma mansoni (Sm) egg (SmEA) and worm antigen (SmWA) preparations isolated from infected baboons. Pronounced B cell responses to SmEA and NK cell responses to both SmEA and SmWA were observed. High levels of IL-2 and IL-21 responses against Sm antigens were observed in T and non-T cells of lymph nodes (LNs) and gut lamina propria-derived lymphocytes (LPLs). Data analysis showed multifunctionality of LN-derived CD4⁺ , CD8⁺ , and CD4⁺ CD8⁺ double positive T cells against either SmWA or SmWA+SmEA antigen preparations. Distinct SmEA-specific multifunctional responses were observed in gut LPLs, suggesting simultaneous responses against egg antigens. These data provide insight into the immune effectors involved in schistosome responses by rhesus macaques.

Management of periampullary adenocarcinoma by pancreaticoduodenectomy at a regional teaching hospital

BACKGROUND

Periampullary adenocarcinoma (PA) includes: pancreatic, duodenal and ampullary adenocarcinoma; and cholangiocarcinoma. Pancreaticoduodenectomy (PD) is required for cure of PA. Previous studies demonstrated the likelihood of cure increases when a microscopically negative (R0) margin is achieved. Clearance of the superior mesenteric artery (SMA) margin has been identified as the most critical margin in PD. Some authors have emphasized the importance of certain techniques to clear the SMA margin. Neither the degree to which these techniques have been incorporated nor their impact on margin status and survival has been described. We hypothesized that use of techniques focusing on clearing the SMA margin would result in higher R0 resection rates and improved survival after PD in patients with PA.

METHODS

A retrospective study was performed on patients from 1/1/1985 until 7/31/2007. Data on patient demographics, clinical presentation, preoperative treatment, operative technique, margins, and postoperative outcomes were collected. Ninety-three patients were identified for inclusion in the study. Three approximately equal groups were created for analysis.

RESULTS

The overall survival (OS) for the entire cohort was 19 months and was not different among the groups studied. Margins were microscopically negative in 81% of cases. The percentage of node-positive cases increased during the time period, as did the number of lymph nodes (LNs) examined (P=0.017). The use of pylorus-preserving PD decreased (P=0.001) while resection of the superior mesenteric/portal vein (SMV/PV) increased during the study period. We observed an increase in descriptions of the clearance of the anterior aspect of the aorta and inferior vena cava (IVC), dissection to the right side of the SMA, dissection to the origin of the SMA and intra-operative identification of the SMA margin. Dissecting to the SMA did not change the likelihood of achieving an R0 margin. OS was improved after R0 resections (R0: 21 months vs. R1/2: 10 months) but this difference was not statistically significant (P=0.099). There was no association between margin status and OS. Changes in the pathology reporting of margins were observed, with statistically significant increases in the percentage of cases in which the SMA, common bile duct and pancreatic neck margins were separately reported. However, the SMA margin was separately reported in only 26% of pathology reports.

CONCLUSIONS

The operative techniques used in PD at this institution have changed over time. The increasing frequency of dissection to the SMA and identification of the SMA margin by both surgeon and pathologist suggest an increased attention to the SMA margin. This shift did not result in significant improvements in survival or margin status, but it is consistent with the recognition of the importance of the SMA margin. Our analysis has also identified areas of potential improvement in the ways in which operative and pathology reports for PD are generated.