Accuracy of ultrasound for the diagnosis of cervical lymph node metastasis in esophageal cancer: a systematic review and meta-analysis

Radiomics diagnostic performance for predicting lymph node metastasis in esophageal cancer: a systematic review and meta-analysis

BACKGROUND

Esophageal cancer, a global health concern, impacts predominantly men, particularly in Eastern Asia. Lymph node metastasis (LNM) significantly influences prognosis, and current imaging methods exhibit limitations in accurate detection. The integration of radiomics, an artificial intelligence (AI) driven approach in medical imaging, offers a transformative potential. This meta-analysis evaluates existing evidence on the accuracy of radiomics models for predicting LNM in esophageal cancer.

METHODS

We conducted a systematic review following PRISMA 2020 guidelines, searching Embase, PubMed, and Web of Science for English-language studies up to November 16, 2023. Inclusion criteria focused on preoperatively diagnosed esophageal cancer patients with radiomics predicting LNM before treatment. Exclusion criteria were applied, including non-English studies and those lacking sufficient data or separate validation cohorts. Data extraction encompassed study characteristics and radiomics technical details. Quality assessment employed modified Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) and Radiomics Quality Score (RQS) tools. Statistical analysis involved random-effects models for pooled sensitivity, specificity, diagnostic odds ratio (DOR), and area under the curve (AUC). Heterogeneity and publication bias were assessed using Deek's test and funnel plots. Analysis was performed using Stata version 17.0 and meta-DiSc.

RESULTS

Out of 426 initially identified citations, nine studies met inclusion criteria, encompassing 719 patients. These retrospective studies utilized CT, PET, and MRI imaging modalities, predominantly conducted in China. Two studies employed deep learning-based radiomics. Quality assessment revealed acceptable QUADAS-2 scores. RQS scores ranged from 9 to 14, averaging 12.78. The diagnostic meta-analysis yielded a pooled sensitivity, specificity, and AUC of 0.72, 0.76, and 0.74, respectively, representing fair diagnostic performance. Meta-regression identified the use of combined models as a significant contributor to heterogeneity (p-value = 0.05). Other factors, such as sample size (> 75) and least absolute shrinkage and selection operator (LASSO) usage for feature extraction, showed potential influence but lacked statistical significance (0.05 < p-value < 0.10). Publication bias was not statistically significant.

CONCLUSION

Radiomics shows potential for predicting LNM in esophageal cancer, with a moderate diagnostic performance. Standardized approaches, ongoing research, and prospective validation studies are crucial for realizing its clinical applicability.

Ultrasound-based radiomics machine learning models for diagnosing cervical lymph node metastasis in patients with non-small cell lung cancer: a multicentre study

BACKGROUND

Cervical lymph node metastasis (LNM) is an important prognostic factor for patients with non-small cell lung cancer (NSCLC). We aimed to develop and validate machine learning models that use ultrasound radiomic and descriptive semantic features to diagnose cervical LNM in patients with NSCLC.

METHODS

This study included NSCLC patients who underwent neck ultrasound examination followed by cervical lymph node (LN) biopsy between January 2019 and January 2022 from three institutes. Radiomic features were extracted from the ultrasound images at the maximum cross-sectional areas of cervical LNs. Logistic regression (LR) and random forest (RF) models were developed. Model performance was assessed by the area under the curve (AUC) and accuracy, validated internally and externally by fivefold cross-validation and hold-out method, respectively.

RESULTS

In total, 313 patients with a median age of 64 years were included, and 276 (88.18%) had cervical LNM. Three descriptive semantic features, including long diameter, shape, and corticomedullary boundary, were selected by multivariate analysis. Out of the 474 identified radiomic features, 9 were determined to fit the LR model, while 15 fit the RF model. The average AUCs of the semantic and radiomics models were 0.876 (range: 0.781-0.961) and 0.883 (range: 0.798-0.966), respectively. However, the average AUC was higher for the semantic-radiomics combined LR model (0.901; range: 0.862-0.927). When the RF algorithm was applied, the average AUCs of the radiomics and semantic-radiomics combined models were improved to 0.908 (range: 0.837-0.966) and 0.922 (range: 0.872-0.982), respectively. The models tested by the hold-out method had similar results, with the semantic-radiomics combined RF model achieving the highest AUC value of 0.901 (95% CI, 0.886-0.968).

CONCLUSIONS

The ultrasound radiomic models showed potential for accurately diagnosing cervical LNM in patients with NSCLC when integrated with descriptive semantic features. The RF model outperformed the conventional LR model in diagnosing cervical LNM in NSCLC patients.

Contrast-enhanced ultrasound (CEUS) in characterization of inconclusive cervical lymph nodes: a meta-analysis and systematic review

Lymph node metastases are common in malignant neoplasms of head and neck. Since cervical lymph nodes (cLN) are localized superficially, ultrasound (US) represents the primary imaging modality. The aim of the study is to report the value of US and contrast-enhanced ultrasound (CEUS) and their diagnostic confidence in the characterization of inconclusive cLN. A systematic review was performed using the literature data base PubMed. Results were filtered (published in a peer-reviewed journal, full-text available, published within the last ten years, species human, English or German full-text) and inclusion criteria were clearly defined (cohort with lymphadenopathy or malignancy in head and neck ≥ 50 patients, histological confirmation of malignant imaging findings, performance of CEUS as outcome variable). The results were quantified in a meta-analysis using a random-effects model. Overall, five studies were included in qualitative and quantitative analysis. The combination of non-enhanced US and CEUS enlarges the diagnostic confidence in the characterization of lymph nodes of unclear dignity. The pooled values for sensitivity and specificity in the characterization of a malignant cervical lymph node using US are 76% (95%-CI 66-83%, I2 = 63%, p < 0.01) and 80% (95%-CI 45-95%, I2 = 92%, p < 0.01), compared to 92% (95%-CI 89-95%, I2 = 0%, p = 0.65) and 91% (95%-CI 87-94%, I2 = 0%, p = 0.40) for the combination of US and CEUS, respectively. Consistent results of the included studies show improved diagnostic performance by additional CEUS. Nevertheless, more prospective studies are needed to implement CEUS in the diagnostic pathway of cLN.

Prognostic Impact of Postoperative Lymph Node Metastases After Neoadjuvant Chemoradiotherapy for Locally Advanced Squamous Cell Carcinoma of Esophagus: From the Results of NEOCRTEC5010, a Randomized Multicenter Study

OBJECTIVE

To determine the prognostic impact of pathologic lymph node (LN) status and investigate risk factors of recurrence in esophageal squamous cell carcinoma (ESCC) patients with pathologic complete response (pCR) after neoadjuvant chemoradiotherapy (NCRT).

SUMMARY BACKGROUND DATA

There are no large-scale prospective study data regarding ypN status and recurrence after pCR in ESCC patients receiving NCRT.

METHODS

The NEOCRTEC5010 trial was a prospective multicenter trial that compared the survival and safety of NCRT plus surgery (S) with S in patients with locally advanced ESCC. The relationships between survival and cN, pN, and ypN status were assessed. Potential prognostic factors in patients with ypN+ and pCR were identified.

RESULTS

A total of 389 ESCC patients (NCRT: 182; S: 207) were included. Patients with pN+ in the S group and ypN+ in the NCRT group had decreased overall survival (OS) and disease-free survival (DFS) compared with pN0 and ypN0 patients, respectively. Partial response at the primary site [hazard ratio (HR), 2.09] and stable disease in the LNs (HR, 3.26) were independent risk factors for lower DFS, but not OS. For patients with pCR, the recurrence rate was 13.9%. Patients with distant LN metastasis had a median OS and DFS of 16.1 months and 14.4 months, respectively. Failure to achieve the median total dose of chemotherapy was a significant risk factor of recurrence and metastasis after pCR (HR, 44.27).

CONCLUSIONS

Persistent pathologic LN metastasis after NCRT is a strong poor prognostic factor in ESCC. Additionally, pCR does not guarantee a cure; patients with pCR should undergo an active strategy of surveillance and adjuvant therapy.

Near-infrared fluorescence-guided resection of micrometastases derived from esophageal squamous cell carcinoma using a c-Met-targeted probe in a preclinical xenograft model

The postoperative survival of esophageal squamous cell carcinoma (eSCC) is notably hindered by cancer recurrence due to difficulty in identifying occult metastases. Cellular mesenchymal-epithelial transition factor (c-Met), which is highly expressed in different cancers, including eSCC, has become a target for the development of imaging probes and therapeutic antibodies. In this study, we synthesized an optical probe (SHRmAb-IR800) containing a near-infrared fluorescence (NIRF) dye and c-Met antibody, which may help in NIRF-guided resection of micrometastases derived from eSCC. Cellular uptake of SHRmAb-IR800 was assessed by flow cytometry and confocal microscopy. In vivo accumulation of SHRmAb-IR800 and the potential application of NIRF-guided surgery were evaluated in eSCC xenograft tumor models. c-Met expression in human eSCC samples and lymph node metastases (LNMs) was analyzed via immunohistochemistry (IHC). Cellular accumulation of SHRmAb-IR800 was higher in c-Met-positive EC109 eSCC cells than in c-Met-negative A2780 cells. Infusion of SHRmAb-IR800 produced higher fluorescence intensity and a higher tumor-to-background ratio (TBR) than the control probe in EC109 subcutaneous tumors (P < 0.05). The TBRs of orthotopic EC109 tumors and LNMs were 3.01 ± 0.17 and 2.77 ± 0.56, respectively. The sensitivity and specificity of NIRF-guided resection of metastases derived from orthotopic cancers were 92.00% and 89.74%, respectively. IHC results demonstrated positive staining in 97.64% (124/127) of eSCC samples and 91.67% (55/60) of LNMs. Notably, increased c-Met expression was observed in LNMs compared to normal lymph nodes (P < 0.0001). Taken together, the results of this study indicated that SHRmAb-IR800 facilitated the resection of micrometastases of eSCC in the xenograft tumor model. This c-Met-targeted probe possesses translational potential in NIRF-guided surgery due to the high positive rate of c-Met protein in human eSCCs.

Accuracy of transvaginal sonoelastography for differential diagnosis between malignant and benign cervical lesions: A systematic review and meta-analysis

BACKGROUND

To evaluate the performance of transvaginal sonoelastography (TVSE) for differential diagnosis between malignant and benign cervical lesions using a meta-analysis.

METHODS

An independent literature search was conducted on the English medical database, including PubMed, Embase and Medline, Cochrane Library, Web of Science, and OVID. The diagnostic accuracy of TVSE was compared with that of histopathology, which is the gold reference standard for diagnosis. The accuracy of TVSE was assessed by calculating the pooled sensitivity, specificity, diagnostic odds ratio, and area under the curve (AUC). The imaging mechanisms, assessment methods, and QUADAS scores were assessed with a meta-regression analysis. A Deeks funnel plot was performed for evaluating publication bias.

RESULTS

Six eligible studies reported a total sample of 615 cervical lesions (415 cancers, 200 benign lesions). TVSE showed a pooled diagnostic odds ratio of 21.42 (95% CI 13.65-33.61), sensitivity of 0.87 (95% CI 0.84-0.90), specificity of 0.79 (95% CI 0.72-0.84), and an AUC of 0.892 (Q* = 0.822). The results of the meta-regression analysis showed that the imaging mechanism (P = .253), the assessment method (P = .279), or QUADAS score (P = .205) did not affect the study heterogeneity.

CONCLUSION

TVSE has a relatively high and satisfactory value for differential diagnosis between malignant and benign cervical lesions. The diagnostic performance of strain elastography and shear wave elastography were similar and good. However, to accommodate heterogeneity and publication bias, high-quality studies are required to further comparative effectiveness analyses to verify the efficacy of ultrasound detection.

Clinical value of ultrasonic imaging in diagnosis of hypopharyngeal cancer with cervical lymph node metastasis

Clinical value of ultrasonic imaging in diagnosis of hypopharyngeal cancer with cervical lymph node metastasis was investigated. Eighty-nine patients who were diagnosed with hypopharyngeal cancer in Qilu Hospital of Shandong University (Qingdao) from January 2014 to June 2016 were retrospectively analyzed. Sixty-eight patients were diagnosed with hypopharyngeal cancer with cervical lymph node metastasis by pathological sections. Twenty-one patients did not have cervical lymph node metastasis. All the patients were diagnosed by palpation and ultrasound. The lymph node ultrasound images were quantified by computer, and the long/short diameter ratio, the maximum systolic velocity, blood flow resistance of the metastatic and non-metastatic patients were compared. The diagnostic efficacy of palpation and ultrasound was analyzed in the diagnosis of hypopharyngeal cancer with cervical lymph node metastasis. A correlation analysis was carried out between the image features of ultrasound and lymph node metastasis. The long/short diameter ratio, maximum systolic velocity and resistance index of patients with lymph node metastasis were significantly higher than those without lymph node metastasis, with a significant difference (P<0.05). Forty-one patients were diagnosed with lymph node metastasis by palpation, fifty-nine patients were diagnosed with lymph node metastasis by ultrasound. The sensitivity and diagnostic coincidence rate of ultrasound in diagnosis of hypopharyngeal cancer with cervical lymph node metastasis were significantly higher than those of palpation (P<0.05). Statistically significant differences were observed in lymph node internal echo types, medullary echo characteristics, envelope definition, and blood flow distribution characteristics between the metastasis group and the non-metastasis group (P<0.05). Lymph node internal echo was heterogeneous. There was no medulla, and the disordered blood flow in the lymph node predicted lymph node metastasis. Preoperative ultrasound has a high diagnostic value in diagnosis of hypopharyngeal cancer with cervical lymph node metastasis. The diagnostic results of preoperative ultrasound can be used as a reference for the diagnosis and treatment of hypopharyngeal cancer with cervical lymph node metastasis.

Measuring inflammation in rheumatoid arthritis with a new clinical and ultrasound index: development and initial validation

With the aim to develop and validate a clinical + ultrasound (US) inflammation score in rheumatoid arthritis (RA) for use in clinical practice, a mixed-method study was conducted. The theoretical development of the index was achieved with qualitative methodology (discussion group and Delphi survey). Subsequently, a cross-sectional study was carried out to analyse issues related to scoring and validation of the new index. RA patients underwent clinical [28 swollen and tender joints count, patient and physician global assessment (PhGA), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP)], and US assessments [synovitis or tenosynovitis by grey-scale (GS) and power Doppler (PD) of 42 structures]. An index was created based on statistical models and expert interaction. Construct validity was tested by correlation with DAS28, SDAI, CDAI, and PhGA. Reliability was evaluated in a subgroup of patients with the intraclass correlation coefficient (ICC). US assessment, CRP, and swollen joints were the items that passed the prioritization phase (Delphi study). For the cross-sectional study, 281 patients were randomly divided into design (n = 141) and validation samples (n = 140). The combination of US sites chosen (7 bilaterally) detected the maximum proportion of synovitis and PD present. Three scoring methods were tested: semiquantitative (0-3 GS + 0-3 PD), dichotomous (0/1 GS + 0/1 PD), and qualitative (0/1 based on algorithm). All showed strong correlation with activity measures (ρ ≥ 0.60), and reliability (ICC 0.89-0.93). The index with best parameters of validity, feasibility, and reliability was the qualitative. The final index chosen was the sum of swollen joint count, US qualitative score, and CRP. The UltraSound Activity score is a valid and reliable measure of inflammation in RA equal to the sum of 28 SJC, a simplified (0/1) US assessment of 11 structures and CRP. It is necessary further investigation to demonstrate additional value over existing indices.

What Is the Optimal Radiotherapy Target Size for Non-Operable Esophageal Cancer? A Meta-Analysis

Definitive radiotherapy has an affirmative role in treating non-operable esophageal cancer; however, the controversy between elective lymph node irradiation (ENI) and involved-field irradiation (IFI) still remains. To ascertain the benefits and disadvantages of the two radiation target volumes, we performed a meta-analysis with 7 related publications. According to our findings, patients treated with ENI and IFI had nearly identical 1, 2, and 3-year survival rates (pooled odds ratio [OR] = 1.004, p = 0.980, and pooled OR = 1.15, p = 0.594, and pooled OR = 0.918, p = 0.679, respectively). Likewise, no significant differences were detected in local recurrence rates (pooled OR = 1.04, p = 0.883), regional recurrence rates (pooled OR = 0.65, p = 0.555), and distant metastasis rates (pooled OR = 1.29, p = 0.309) between the two treatment groups. However, IFI could significantly decrease the incidences of acute radiation esophagitis (pooled OR = 2.30, p = 0.001) and late pneumonia (pooled OR = 2.52, p = 0.04) compared with ENI. This meta-analysis provides evidence that IFI is more feasible for non-operable esophageal cancer than ENI.

Meta-analysis of ultrasound for cervical lymph nodes in papillary thyroid cancer: Diagnosis of central and lateral compartment nodal metastases

PURPOSE

To evaluate the performance of preoperative ultrasound in the diagnosis of cervical lymph nodes metastases (CLNM) of papillary thyroid cancer (PTC) and its value in assisting cervical lymph node dissection (CLND).

METHODS

PubMed, EMBASE and Cochrane Library databases were searched to identify relevant studies up to Sep. 2017. Overall sensitivity, specificity, and diagnostic odds ratio (DOR) were used to assess the diagnostic efficacy of ultrasound in detecting central and lateral CLNM of PTC.

RESULTS

Nineteen studies comprising 4014 patients were included in the meta-analysis. The pooled sensitivity, specificity, DOR and area under curve (AUC) of ultrasound in detecting central CLNM were 0.33 (95% confidence interval (95% CI): 0.31-0.35), 0.93 (95% CI: 0.92-0.94), 5.63 (95% CI: 3.50-9.04), and 0.69, respectively; and lateral CLNM were 0.70 (95% CI: 0.68-0.72), 0.84 (95% CI: 0.82-0.85), 18.7 (95% CI: 10.3-33.9) and 0.88, respectively. We found that the rate of central CLNM of PTC was 48.0%, and 36.2% of the dissected lymph nodes were metastatic, meanwhile, the rate of lateral CLNM of PTC was 59.2%, and 46.6% of the dissected lymph nodes were metastatic in the meta-analysis.

CONCLUSIONS

Preoperative ultrasound demonstrates poor sensitivity in the diagnosis of central CLNM, and good diagnostic efficacy for lateral CLNM of PTC. Prophylactic central CLND is recommended to PTC patients due to the high incidence of central CLNM and low diagnostic efficacy of ultrasound.

The limited role of elective neck dissection in patients with cN0 salivary gland carcinoma

PURPOSE

To evaluate whether elective neck dissection (END) was beneficial for cN0 patients with salivary gland carcinoma.

MATERIALS AND METHODS

The rates of regional failure-free survival and disease-free survival were calculated using Kaplan-Meier methods and Cox models. The risk factors for occult lymph node metastasis (OLNM) in cN0 patients undergoing END was analyzed using logistic regression. A nomogram was formulated to calculate the estimated probability of OLNM.

RESULTS

Neck dissection was performed in 84 patients (43.3%). OLNM was detected in eight of the patients who underwent END. During the follow-up period, regional recurrences involving cervical lymph nodes were found in 10 patients. Cox model analysis revealed that neck dissection was not related to regional failure-free survival and disease-free survival. Logistic regression analysis revealed that older age, neural symptoms, and positive adjacent lymph nodes were associated with OLNM. A nomogram comprising age, neural symptoms, and adjacent lymph nodes was developed to predict the risk of OLNM.

CONCLUSION

The incidence of OLNM was low in cN0 patients after detailed preoperative evaluations. There was no strong evidence supporting END as a conventional therapy in cN0 patients with salivary cancers. Our nomogram is a simple and practical instrument for strengthening the prediction of OLNM.

Cervical ultrasonography has no additional value over negative 18F-FDG PET/CT scans for diagnosing cervical lymph node metastases in patients with oesophageal cancer

Objectives

To investigate the additional value of cervical ultrasonography over ¹⁸F-FDG PET/CT for diagnosing cervical lymph node metastases in patients with newly diagnosed oesophageal cancer.

Methods

Between January 2013 and January 2016, 163 patients with newly diagnosed oesophageal cancer underwent both cervical ultrasonography and ¹⁸F-FDG PET/CT at a tertiary referral centre in the Netherlands. Retrospective clinical data analysis was performed to assess the diagnostic value of cervical ultrasonography and ¹⁸F-FDG PET/CT for the detection of cervical lymph node metastases. Fine needle aspiration or clinical follow-up was used as reference standard.

Results

The overall incidence of patients with cervical lymph node metastases was 14%. The sensitivity of ¹⁸F-FDG PET/CT to detect cervical lymph node metastases was 82% (95% CI 59–94%) and specificity was 91% (95% CI 85–95%). The sensitivity and specificity of cervical ultrasonography were 73% (95% CI 50–88%) and 84% (95% CI 77–90%), respectively. In patients with a negative ¹⁸F-FDG PET/CT, 12 of 133 (9%) patients had suspicious nodes on cervical ultrasonography. In all these 12 patients the nodes were confirmed benign.

Conclusions

Cervical ultrasonography has no additional diagnostic value to a negative integrated ¹⁸F-FDG PET/CT for the detection of cervical lymph node metastases in patients with newly diagnosed oesophageal cancer.

Key Points

• Cervical ultrasonography has no value over PET/CT in evaluating cervical node metastases.

• PET/CT provides greater diagnostic confidence compared to cervical ultrasonography.

• Cervical ultrasonography during standard diagnostic work-up may be considered unnecessary.

• Cervical lesions on PET/CT require cytopathological confirmation by FNA.