O-BN07 Transesophageal Endoscopic Resection of Mediastinal Cysts

Background Primary mediastinal cysts are infrequent lesions derived from a variety of mediastinal organs or structures. Complete surgical resection is the treatment of choice even in asymptomatic patients to prevent severe adverse events (AEs) and establish the diagnosis. Transesophageal endoscopic resection of benign mediastinal tumors has been proven feasible. The aim of this study is to evaluate the feasibility, safety and efficacy of transesophageal endoscopic surgery for mediastinal cysts. Methods From January 2016 to May 2021, patients with mediastinal cysts who underwent transesophageal endoscopic resection were retrospectively included. Clinicopathological characteristics, procedure-related parameters, AEs, and follow-up outcomes were analyzed. Results A total of 10 patients with mediastinal cysts were included in this study. The mean cyst size was 3.3±1.3 cm. Histopathology revealed 3 bronchogenic cysts (30.0%), 4 esophageal duplication cysts (40.0%), 2 gastroenteric cysts (20.0%), and 1 lymphatic cyst (10.0%). All procedures were performed uneventfully. En bloc resection was achieved in 6 patients (60.0%). Aggressive resection was avoided to prevent damage to the surrounding vital organs. Mean procedure time was 63.4±36.5 min. No major pneumothorax, bleeding, mucosal injury or fistula occurred. One patient had a transient febrile episode (>38.5 °C). Mean postoperative hospital stay was 2.7±0.9 days. No residual or recurrent lesions were observed in any patient during a mean follow-up period of 29.8±19.5 months. Conclusions Transesophageal endoscopic surgery appears to be a feasible, safe, effective and much less invasive approach for mediastinal cyst resection. Larger prospective studies are required to fully assess the efficacy and safety of this novel technique.

Surgical resection of a giant pericardial cyst: a case report

Background Pericardial cysts are rare congenital mediastinal cysts. They are typically asymptomatic and are often discovered incidentally, although some patients may present with chest pain and dyspnoea. Asymptomatic patients are managed conservatively with multiple modalities, with surgical resection often recommended for symptomatic patients only. The frequency of follow-up imaging has yet to be established. Case summary We report a case of a 59-year-old female with a gradually increasing pericardial cyst, first noted 10 years prior as an abnormal cardiac silhouette on routine chest radiography. Further evaluation confirmed the presence of a pericardial cyst compressing the left ventricle with new-onset atrial fibrillation. The patient underwent successful thoracoscopic excision of the pericardial cyst under general anaesthesia. The patient’s post-operative course was uneventful, and she was ultimately discharged in stable condition. Discussion Pericardial cysts are typically benign, but complications may arise in the case of compression of adjacent cardiac structures, inflammation, haemorrhage, or rupture of the cyst. Magnetic resonance imaging is considered the better modality for both diagnosis and follow-up of pericardial cysts. This case illustrates the need for long-term clinical follow-up in order to optimize the time for treatment.

THE “HIGH-RIDING” SUPERIOR PERICARDIAL RECESS

The presence of prominent physiological fluid in the posterior part of the superior pericardial recess is known as "high-riding pericardial recess" (HRPR). Even in series studies with high numbers, the amount of liquid in this area was measured with a maximum 1,4 cm in size. Our case report is the biggest HRPR in diameter. HRPRs have clinical significance since they are in the differential diagnosis with lymph nodes and mediastinal cysts. We present a 57-year-old patient with clinical and radiological findings.

Should Spring Water Cysts of the Mediastinum Require Excisional Resection?

Complete surgical excision is the standard therapy for mediastinal cysts. Translucent cysts containing crystal-clear fluid are called “spring water cysts.” We considered that these cysts can be treated adequately using fenestration with minimal bleeding and damage to existing structures. We experienced a case of mediastinal spring water cyst fenestrated under video-assisted thoracoscopy with a miniaturized endoscope (mini-VATS), instead of excisional resection. Fenestration of the non-neoplastic mediastinal cyst under mini-VATS might be a less invasive radical procedure and an alternative to complete resection. We discuss the indication for surgery and the surgical procedure for non-neoplastic mediastinal cyst with crystal-clear fluid.

Can computed tomography-based radiomics potentially discriminate between anterior mediastinal cysts and type B1 and B2 thymomas?

Background Anterior mediastinal cysts (AMC) are often misdiagnosed as thymomas and undergo surgical resection, which caused unnecessary treatment and medical resource waste. The purpose of this study is to explore potential possibility of computed tomography (CT)-based radiomics for the diagnosis of AMC and type B1 and B2 thymomas. Methods A group of 188 patients with pathologically confirmed AMC (106 cases misdiagnosed as thymomas in CT) and thymomas (82 cases) and underwent routine chest CT from January 2010 to December 2018 were retrospectively analyzed. The lesions were manually delineated using ITK-SNAP software, and radiomics features were performed using the artificial intelligence kit (AK) software. A total of 180 tumour texture features were extracted from enhanced CT and unenhanced CT, respectively. The general test, correlation analysis, and LASSO were used to features selection and then the radiomics signature (radscore) was obtained. The combined model including radscore and independent clinical factors was developed. The model performances were evaluated on discrimination, calibration curve. Results Two radscore models were constructed from the unenhanced and enhanced phases based on the selected four and three features, respectively. The AUC, sensitivity, and specificity of the enhanced radscore model were 0.928, 89.3%, and 83.8% in the training dataset and 0.899, 84.6%, and 87.5% in the test dataset (higher than the unenhanced radscore model). The combined model of enhanced CT including radiomics features and independent clinical factors yielded an AUC, sensitivity and specificity of 0.941, 82.1%, and 94.6% in the training dataset and 0.938, 92.3%, and 87.5% in the test dataset (higher than the unenhanced combined model and enhanced radscore model). Conclusions The study suggested the possibility that the combined model in enhanced CT provided a potential tool to facilitate the differential diagnosis of AMC and type B1 and B2 thymomas.

Can Computed Tomography-Based Radiomics Potentially Discriminate Between Anterior Mediastinal Cysts and type B1 and B2 thymomas?

Background: Anterior mediastinal cysts (AMC) are often misdiagnosed as thymomas and undergo surgical resection, which caused unnecessary treatment and medical resources waste. The purpose of this study is to explore potential possibility of computed tomography (CT)-based radiomics for the diagnosis of AMC and type B1 and B2 thymomas.Methods: A group of 188 patients with pathologically confirmed AMC (106 cases misdiagnosed as thymomas in CT) and thymomas (82 cases) and underwent routine chest CT from January 2010 to December 2018 were retrospectively analyzed. The lesions were manually delineated using ITK-SNAP software, and radiomics features were performed using the Artificial Intelligence Kit (AK) software. A total of 396 tumor texture features were extracted from enhanced CT and unenhanced CT, respectively. The general test, correlation analysis and LASSO were used to features selection and then the radiomics signature (radscore) were obtained. The combined model including radscore and independent clinical factors were developed. The model performances were evaluated on discrimination, calibration curve.Results: Two radscore model were constructed from the unenhanced and enhanced phases based on the selected 4 and 3 features, respectively. The AUC, sensitivity, and specificity of the enhanced radscore model were 0.928, 89.3% and 83.8% in the training dataset and 0.899, 84.6%, 87.5% in the test dataset (higher than the unenhanced radscore model). The combined model of enhanced CT including radiomics features and independent clinical factors yielded an AUC, sensitivity and specificity of 0.941, 82.1%, and 94.6% in the training dataset and 0.938, 92.3%, and 87.5% in the test dataset (higher than the unenhanced combined model and enhanced radscore model). Conclusions: The study suggested the possibility that the combined model in enhanced CT provided a potential tool to facilitate the differential diagnosis of AMC and type B1 and B2 thymomas.

Can Computed Tomography-Based Radiomics Potentially Discriminate Between Anterior Mediastinal Cysts and Type B1 and B2 Thymomas

Background: Anterior mediastinal cysts (AMC) are often misdiagnosed as thymomas and undergo surgical resection, which caused unnecessary treatment and medical resources waste. The purpose of this study was to explore potential possibility of computed tomography (CT)-based radiomics for the diagnosis of AMC and type B1 and B2 thymomas. Methods: A group of 188 patients with pathologically confirmed AMC (106 cases mischarged as thymomas in CT) and thymomas (82 cases) and underwent routine chest CT from January 2010 to December 2018 were retrospectively analyzed. The lesions were manually delineated using ITK-SNAP software, and radiomics features were performed using the Artificial Intelligence Kit (AK) software. A total of 396 tumor texture features were extracted from enhanced CT and unenhanced CT, respectively. The general test, correlation analysis and LASSO were used to features selection and then the radiomics signature (radscore) were obtained. The combined model including radscore and independent clinical factors were developed. The model performances were evaluated on discrimination, calibration curve. Results: Two radscore model were constructed from the unenhanced and enhanced phases based on the selected 4 and 3 features, respectively. The AUC, sensitivity, and specificity of the enhanced radscore model were 0.928, 89.3% and 83.8% in the training dataset and 0.899, 84.6%, 87.5% in the test dataset (higher than the unenhanced radscore model). The combined model of enhanced CT including radiomics features and independent clinical factors yielded an AUC, sensitivity and specificity of 0.941, 82.1%, and 94.6% in the training dataset and 0.938, 92.3%, and 87.5% in the test dataset (higher than the unenhanced combined model and enhanced radscore model). Conclusions: The study suggested the possibility that the combined model in enhanced CT provided a potential tool to facilitate the differential diagnosis of AMC and type B1 and B2 thymomas.