Diagnostic value of 18F-fluorodeoxyglucose positron-emission tomography/computed tomography for preoperative lymph node metastasis of esophageal cancer: A meta-analysis

Threshold size criterion to suspect malignant supraclavicular lymph node < 10 mm in esophageal cancer

OBJECTIVES

To determine the threshold size for predicting metastasis of supraclavicular lymph nodes (SCLNs) < 10 mm on axial and multiplanar reconstruction CT in esophageal squamous cell carcinoma (ESCC).

METHODS

This retrospective, multicenter study received approval from three institutional review boards, which waived informed consent. Patients with ESCC had ultrasound-guided fine-needle aspiration biopsy (US-FNAB) for SCLNs, with contrast-enhanced CT performed within 2 weeks prior to US-FNAB. A CT and ultrasound radiologist jointly analyzed images to identify and mark biopsied SCLNs < 10 mm on CT, followed by two blinded radiologists who independently measured short-axis diameter (SAD), long-axis diameter (LAD), short diameter of multiplanar reconstruction (SD-MPR), long diameter of multiplanar reconstruction (LD-MPR) and the intra-class correlation coefficient (ICC) was analyzed. Center 1 included 220 SCLNs as the training set, and Centers 2 + 3 included 75 SCLNs as the validation set. The optimal cutoff value was determined using receiver operating characteristic (ROC) curves.

RESULTS

In the training and validation sets, 31.8% (70/220) and 32.0% (24/75) of SCLNs were positive. ICC for SAD was excellent (ICC = 0.847). The area under the receiver operating characteristic curve of SAD was 0.832 in the training set, higher than others, with a cutoff value of > 6 mm, resulting in sensitivity, specificity, positive predictive value, negative predictive value, accuracy of 77.1%, 80.7%, 65.0%, 88.3%, 79.1%, respectively. In the validation set, these metrics were 87.5%, 74.5%, 61.8%, 92.7%, 81.0%, respectively.

CONCLUSION

SAD on CT can suspect metastasis of SCLN < 10 mm in ESCC patients, with a threshold size of > 6 mm.

CLINICAL RELEVANCE STATEMENT

Determining the threshold size criterion on CT images may enhance the prediction of supraclavicular lymph node metastasis in esophageal squamous cell carcinoma patients, thereby benefiting diagnostic and therapeutic strategies.

KEY POINTS

Supraclavicular lymph nodes < 10 mm in esophageal carcinoma are indeterminate for malignancy. Supraclavicular lymph nodes > 6 mm are highly suspicious for malignancy. The metastasis status of supraclavicular lymph nodes is critical for staging esophageal carcinoma.

Value of Computed Tomography Scan for Detecting Lymph Node Metastasis in Early Esophageal Squamous Cell Carcinoma

BACKGROUND

The necessity of computed tomography (CT) scan for detecting potential lymph node metastasis (LNM) in early esophageal squamous cell carcinoma (ESCC) before endoscopic and surgical treatments is under debate.

METHODS

Patients with histologically proven ESCC limited to the mucosa or submucosa were examined retrospectively. Diagnostic performance of CT for detecting LNM was analyzed by comparing original CT reports with pathology reports. The sensitivity, specificity, accuracy, positive predictive value (PPV), and negative predictive value (NPV) were calculated.

RESULTS

A total of 625 patients from three tertiary referral hospitals were included. The rate of pathologically confirmed LNM was 12.5%. Based on original CT reports, the sensitivity, specificity, accuracy, PPV, and NPV of CT to determine LNM in T1 ESCC were 41.0%, 83.2%, 77.9%, 25.8%, and 90.8% respectively. For mucosal cancers (T1a), these parameters were 50.0%, 81.7%, 80.9%, 6.8%, and 98.4%, respectively. For submucosal cancers (T1b), they were 40.0%, 85.0%, 75.0%, 43.0%, and 83.3%, respectively. Additionally, the diagnostic performance of CT for LNM was relatively better for ESCC in the lower esophagus. Pathologically, 69.2% of patients with LNM did not exhibit lymphovascular invasion (LVI), and the sensitivity of CT for recognizing LNM in these patients (33.3%) was lower than those with LVI (58.3%).

CONCLUSIONS

Computed tomography can detect nearly half of the LNM cases in early ESCC with high specificity. The performance of CT further improved in LNM cases with LVI. Therefore, we conclude that routine preoperative CT for the assessment of potential LNM risk in patients with early ESCC is necessary.

FAPI-PET/CT guided radiotherapy for patients with esophageal cancer

BACKGROUND

Cancer associated fibroblasts have become a target of interest in different malignancies for positron emission tomography (PET) imaging, using positron emitter labelled fibroblast activation protein inhibitors (FAPI). New data underline the advanced imaging properties of FAPI-PET/CT for the staging of esophageal cancer compared to standard imaging. Potential benefits of FAPI-PET/CT in radiation therapy planning are the subject of this investigation.

METHODS

Ten patients with newly diagnosed esophageal cancer treated with radiochemotherapy (RCT) were retrospectively analyzed. All patients underwent [68Ga]OncoFAP-PET/CT in treatment position to facilitate radiation treatment planning. Six patients received neoadjuvant RCT as part of a trimodal therapy and four patients underwent definitive RCT. In five cases, restaging after initial treatment was performed with FAPI-PET/CT.

RESULTS

[68Ga]OncoFAP-PET/CT based imaging showed a high correlation with the endoscopic staging for initial imaging. In three cases, new sites of disease were unmasked, not visible in CT- and endosonographic staging. [68Ga]OncoFAP-PET/CT based RT delineation offered good definition of clinical target volumes, especially in retro-/paracardial areas and the gastroesophageal junction.

CONCLUSION

[68Ga]OncoFAP-PET/CT may aid and improve radiation treatment planning for patients with esophageal cancer.

Personalised PET imaging in oncology: an umbrella review of meta-analyses to guide the appropriate radiopharmaceutical choice and indication

PURPOSE

For several years, oncological positron emission tomography (PET) has developed beyond 2-deoxy-2-[18F]fluoro-D-glucose ([18F]FDG). This umbrella review of meta-analyses aims to provide up-to-date, comprehensive, high-level evidence to support appropriate referral for a specific radiopharmaceutical PET/computed tomography (CT) or PET/magnetic resonance (MR) in the diagnosis and staging of solid cancers other than brain malignancies.

METHODS

We performed a systematic literature search on the PubMed/MEDLINE and EMBASE databases for meta-analyses assessing the accuracy of PET/CT and/or PET/MRI with [18F]FDG, somatostatin- receptor-targeting 68Ga-DOTA-peptides, 18F-labelled dihydroxyphenylalanine ([18F]DOPA), prostate-specific membrane antigen (PSMA)-targeted radioligands, and fibroblast activation protein inhibitors (FAPI) in the diagnosis/disease characterisation and staging of solid cancers other than brain tumours.

RESULTS

The literature search yielded 449 scientific articles. After screening titles and abstracts and applying inclusion and exclusion criteria, we selected 173 meta-analyses to assess the strength of evidence. One article was selected from references. Sixty-four meta-analyses were finally considered. The current evidence corroborates the role of [18F]FDG as the main player in molecular imaging; PSMA tracers are useful in staging and re-staging prostate cancer; somatostatin-targeting peptides (e.g. [68Ga]Ga- DOTA-TOC and -TATE) or [18F]DOPA are valuable in neuroendocrine tumours (NETs). FAPI has emerged in gastric cancer assessment. According to search and selection criteria, no satisfactory meta-analysis was selected for the diagnosis/detection of oesophageal cancer, the diagnosis/detection and N staging of small cell lung cancer and hepatic cell carcinoma, the diagnosis/detection and M staging of melanoma and Merkel cell carcinoma, cervical, vulvar and penis cancers, the N and M staging of lung and gastroenteropancreatic NET, testicular cancer, and chondrosarcoma, and the M staging of differentiated thyroid, bladder and anal cancers.

CONCLUSION

The comprehensive high-level evidence synthesised in the present umbrella review serves as a guiding compass for clinicians and imagers, aiding them in navigating the increasingly intricate seascape of PET examinations.

Stratification of lymph node metastasis improves diagnostic efficiency in thoracic esophageal squamous cell carcinoma

INTRODUCTION

Difference of the short diameter of lymph nodes in the main regions of esophageal squamous cell carcinoma (ESCC) and its value in the diagnosis of lymph nodes need to explore.

METHODS

The clinical data of patients with thoracic ESCC who underwent surgical treatment in our hospital were collected. The short diameters of the largest lymph node in each region of the patient were measured by preoperative enhanced computed tomography (CT) and were compared with the postoperative pathology.

RESULTS

A total of 477 patients with thoracic ESCC who did not receive neoadjuvant therapy were enrolled in this study. The receiver operating characteristic curve suggested that the short diameters of the paracardial nodes, the left gastric nodes, the right recurrent laryngeal nerve nodes, and the left recurrent laryngeal nerve nodes could well predict the postoperative pathology of the lymph nodes, with area under curve (AUC) of 0.958, 0.937, 0.931, and 0.915, the corresponding cut-off values of 5.7 mm, 5.7 mm, 5.5 mm, and 4.8 mm, the corresponding sensitivities of 94.7%, 85.4%, 88.7%, and 79.4%, and the corresponding specificities of 93.7%, 96.3%, 86.2%, and 95.0%, respectively. The AUC of the thoracic paraesophageal lymph nodes, the subcarinal nodes and all regional lymph nodes were 0.845, 0.688, and 0.776, respectively.

CONCLUSION

Region-based criterion for lymph node metastasis of thoracic ESCC is beneficial to improve the diagnostic efficiency of preoperative CT.

FAPI PET/CT research progress in digestive system tumours

¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography has been used in clinical practice for many years. This modality is of great value for tumour diagnosis, staging, and efficacy evaluations, but it has many limitations in the diagnosis and treatment of digestive system tumours. Fibroblast activation protein is highly expressed in gastrointestinal tumours. Various isotope-labelled fibroblast activation protein inhibitors are widely used in clinical research. These inhibitors have low background uptake in the brain, liver and oral/pharyngeal mucosa and show good contrast between the tumour and background, which makes up for the lack of fluorodeoxyglucose in the diagnosis of digestive system tumours. It better displays the primary tumours, metastases and regional lymph nodes of digestive system tumours, such as oesophageal cancer, gastric cancer and liver cancer, and also provides a new method for treating these tumours. Based on this background, this article introduces the current research status of fibroblast activation protein inhibitor positron emission tomography/computed tomography in various types of digestive system malignant tumours to provide more valuable information for diagnosing and treating digestive system tumours.

Modified method to improve the diagnostic efficiency of 18F-FDG PET/CT in regional lymph node metastasis of esophageal squamous cell carcinoma

Background

Regional lymph node (LN) metastasis is a significant factor influencing the treatment choice of esophageal squamous cell carcinoma (ESCC). The performance PET/CT as an imaging evaluation method for regional LNs in ESCC, is unsatisfactory due to the lack of logical criterion. We explored how a modified criterion improved the diagnostic value of ¹⁸F-FDG PET/CT in regional LN metastasis.

Methods

The data from 111 patients with ESCC were analyzed retrospectively. All patients underwent preoperative PET/CT examination, resection of the cancer, and regional LN dissection. The PET/CT images were interpreted by two experienced diagnosticians. LNs were allocated to five subregions. Each LN was diagnosed by two diagnostic criteria of PET/CT (traditional criterion and the modified criterion) one by one across the same field, and the accuracy of PET/CT was determined using the histopathologic results as the reference standard.

Results

A total of 4,847 LNs were dissected, of which 147 were confirmed as metastases by postoperative pathology. A total of 656 LNs were screened by ¹⁸F-FDG PET/CT imaging. The determination of all 656 LNs by PET/CT was compared with the pathological results. The diagnostic accuracy of the modified and traditional criteria for the five subregions (paraesophageal, neck, upper mediastinal, middle-lower mediastinal and ventral subregions) was: 74.60% vs. 61.90%, 86.44% vs. 81.36%, 90.26% vs. 70.78%, 96.19% vs. 75.09%, and 87.91% vs. 85.71%, respectively.

Conclusions

The modified diagnostic criterion had better diagnostic efficiency because it combined PET and CT imaging data.

Incidence and relevance of clinically indeterminate nonregional lymph nodes in the treatment of oesophageal cancer

OBJECTIVES

Metastatic involvement of nonregional supraclavicular or superior mediastinal lymph nodes in distal oesophageal cancer is rare but has important implications for prognosis and management. The management of nonregional lymph nodes which appear indeterminate on CT and FDG PET-CT (subcentimeter nodes or those with preserved normal morphology, but increased FDG avidity) can present a diagnostic dilemma. This study investigates the incidence, work-up and clinical significance of nonregional clinically indeterminate FDG avid lymph nodes.

METHODS

A single-centre retrospective review of all FDG PET-CT scans conducted over 5 years was conducted. Patients with mid- or distal oesophageal cancer with nonregional FDG avid nodes were identified. Subsequent work-up, management and outcomes were retrieved from electronic health records.

RESULTS

Reports for 1189 PET-CT scans were reviewed. A total of 79 patients met the inclusion criteria. Of these, 18 (23%) were deemed to have disease and performance status potentially amenable to radical surgery and underwent further assessment. The indeterminate lymph nodes were successfully sampled via endobronchial ultrasound (EBUS) or ultrasound-guided fine-needle aspiration (US-FNA) in 100% of cases. 15/18 (83.3%) of samples were benign and proceeded to surgery. Outcomes for patients who proceeded to surgery were similar to other cohorts. None had pathology suggesting false-negative lymph node sampling.

CONCLUSIONS

EBUS and US-FNA are effective means of sampling clinically indeterminate nonregional lymph nodes, and can significantly impact prognosis, and management. Further investigations in this context are of value in this cohort and should be pursued. Nonregional clinically indeterminate lymph nodes represent a diagnostic dilemma in oesophageal cancer staging. Additional investigations in the form of endobronchial ultrasound are effective at providing additional staging information, and can substantially influence patient care.

Role of Imaging in Esophageal Cancer Management in 2020: Update for Radiologists

OBJECTIVE. The purpose of this article is to discuss the role of imaging in the management of esophageal cancer. CONCLUSION. A multimodality-based approach to imaging is essential in clinical practice to achieve the best possible outcome for patients with esophageal cancer. Radiologists must be aware of the strengths and limitations of different imaging modalities in various clinical settings. The role of a radiologist is to combine information from anatomic and functional imaging, assess metastatic disease and changes in the primary tumor during treatment, and identify anatomic complications after treatment.

Role of precision imaging in esophageal cancer

Esophageal cancer is a major cause of morbidity and mortality worldwide. Recent advancements in the management of esophageal cancer have allowed for earlier detection, improved ability to monitor progression, and superior treatment options. These innovations allow treatment teams to formulate more customized management plans and have led to an increase in patient survival rates. For example, in order for the most effective management plan to be constructed, accurate staging must be performed to determine tumor resectability. This article reviews the multimodality imaging approach involved in making a diagnosis, staging, evaluating treatment response and detecting recurrence in esophageal cancer.

Clinical evaluation of right recurrent laryngeal nerve nodes in thoracic esophageal squamous cell carcinoma

Background

The accuracy of clinical N staging of esophageal squamous cell carcinoma is suboptimal. As an important station of lymph node metastasis, station C201 (right recurrent laryngeal nerve nodes) has rarely been evaluated alone. We aimed to explore an effective way to evaluate the right recurrent laryngeal nerve nodes in thoracic esophageal squamous cell carcinoma.

Methods

We retrospectively analyzed 628 thoracic esophageal squamous cell carcinoma patients who underwent radical resection without neoadjuvant therapy from two Chinese cancer centers. The diameter of the short axis of the largest right recurrent laryngeal nerve node (DC201) was measured on contrast-enhanced multi-slice computed tomography (MSCT). Right recurrent laryngeal nerve nodes were examined by postoperative pathologic results. The receiver operating characteristic (ROC) curve was generated to assess the diagnostic capabilities of DC201 to determine the right recurrent laryngeal nerve nodes status.

Results

ROC curve analysis revealed that the optimal cut-off point of DC201 was 6 mm, with an area under curve (AUC), sensitivity, specificity, and Youden index of 0.896, 71.9%, 88.8%, and 0.607 respectively. When the cut-off point of DC201 was set to 10 mm, sensitivity, specificity and the Youden index were 14.1%, 99.6% and 0.137 respectively. Among 128 patients with right recurrent laryngeal nerve node metastasis, 71 and 108 patients had the largest right recurrent laryngeal nerve node located above the suprasternal notch level and in the tracheoesophageal groove respectively.

Conclusions

When DC201 ≥6.0 mm instead of DC201 ≥10 mm was used to dictate the right recurrent laryngeal nerve nodes metastasis, contrast-enhanced MSCT could evaluate the status of right recurrent laryngeal nerve nodes with high sensitivity and specificity. The largest right recurrent laryngeal nerve nodes were mainly located in the tracheoesophageal groove and/or above the suprasternal notch.