Mediastinal Research Articles

The case of migration of a fragment of a Kirchner wire to the ascending aorta

Fracture and migration of fragments of a Kirchner wire is a rare but potentially dangerous complication after treatment of clavicle injuries. In the presented clinical case, the fracture of the Kirchner wire occurred 2 months after the fixation of the sternoclavicular joint. The fragment of the Kirchner wire migrated into the anterior mediastinum, penetrated into the ascending aorta with the formation of an anterior mediastinal hematoma and right-sided hemothorax. The fragment of the Kirchner wire was successfully extracted during the operation through median sternotomy. In this case, the Kirchner wire did not damage other structures and was extracted without the use of cardiopulmonary bypass.

Aortic Wall Abrasion Caused by Needle Injury after Endoscopic Ultrasound-Guided Fine Needle Aspiration of a Mediastinal Hemangioma

Benign mediastinal cysts are challenging to diagnose. Although Endoscopic Ultrasound (EUS) and EUS-guided fine needle aspiration (FNA) can accurately diagnose mediastinal foregut cysts, little is known about their complications. This paper reports a rare case in which EUS-FNA performed on mediastinal hemangioma resulted in an aortic hematoma. A 29-year-old female patient was commissioned for EUS of an asymptomatic accidental mediastinal lesion. Chest CT revealed a 4.9×2.9×10.1 cm thin-walled cystic mass in the posterior mediastinum. EUS revealed a large, anechoic cystic lesion with a regular thin wall with negative Doppler. EUS-guided FNA was performed using a single-use 19-gauge aspiration needle (EZ Shot 3; Olympus, Tokyo, Japan), and approximately 70 cc of serous pinkish fluid was aspirated. The patient was in a stable condition with no signs of acute complication. One day after EUS-FNA, thoracoscopic resection for mediastinal mass was conducted. The purple and multi-loculated large cyst was removed. Upon removal, however, an aortic hematoma caused by a focal descending aortic wall injury was observed. After a few days of close observation, the patient was discharged upon stable 3D aorta angio CT findings. This paper reports a rare and severe complication of EUS-FNA, in which an aspiration needle caused a direct injury to the aorta. The injection must be performed carefully to avoid damaging the adjacent organs or digestive tract walls.

Primary Neuroblastoma of the Thymus.

Primary neuroblastoma is the most common extracranial solid tumor in children and may occur anywhere along the sympathetic chain, but most commonly occur in abdominal/retroperitoneal region including the adrenal glands, followed by the thorax. In children, the most primary neuroblastomas in the thorax are in the posterior mediastinum. We present herein an extremely rare case of primary neuroblastoma of thymus in pediatric patient.

Efficacy and Postoperative Outcomes of Laparoscopic Retrosternal Route Creation for the Gastric Conduit: Propensity Score-Matched Comparison to Posterior Mediastinal Reconstruction.

Retrosternal reconstruction has lower risks for severe postoperative morbidities, such as gastro-tracheal fistula or esophageal hiatal hernia. We have previously reported the laparoscopic retrosternal route creation (LRRC) method, but its safety and efficacy remain unclear. In total, 374 patients with esophageal carcinoma who underwent minimally invasive McKeown esophagectomy in the prone position between 2010 and 2021 were retrospectively reviewed. We performed a propensity score-matched analysis with the simple, nearest-neighbor method and no calipers to compare postoperative outcomes and reconstructed gastric conduit functionality between patients who underwent LRRC and counterparts who underwent posterior mediastinal reconstruction. After matching, 62 patients were included in the laparoscopic retrosternal group (LR group) or posterior mediastinal group (PM group). No significant differences were observed between the groups, apart from the number of robot-assisted surgeries, the extent of lymph node dissection, and the method of cervical anastomosis. There were no significant differences in the incidence of Clavien-Dindo grade ≥ 2 complications. Gastro-tracheal fistula (n = 1) and esophageal hiatal hernia (n = 2) occurred in the PM group but not in the LR group. There were no differences in the incidence of pulmonary embolism between the groups (5% vs. 5%). The postoperative anastomotic stenosis rate was similar (16% vs. 27%, p = 0.192). Endoscopic findings of reflux esophagitis (modified Los Angeles classification≥ M) at 1 year after surgery were significantly better in the LR group (p = 0.037). LRRC for gastric conduit reconstruction is safe and valuable. It is associated with good reconstructed gastric conduit function.

Posterior mediastinal Ewing sarcoma with multiple metastases on FDG PET/CT: a rare entity

BackgroundEwing sarcoma and peripheral primary neuroendocrine tumors are aggressive neoplasms which consist of small, round, blue cells of neuroectodermal origin. They usually arise from the skeleton and consist of genetic mutations EWSR1 in chromosome 22 and FL1 gene on chromosome 11. Extraskeletal Ewing sarcomas (EES) are rare entities with most common sites of EES being extremities, head and neck region and retroperitoneum. Posterior mediastinal Ewing sarcoma is rare. For its evaluation, 18F-fluorodeoxyglucose positron emission tomography (18F FDG PET/CT) plays significant role in staging, management planning and prognostication.Case presentationWe describe a rare case of EES of posterior mediastinum in a 20-year-old boy who presented with signs of upper motor neuron lesion below D10 level. Contrast-enhanced magnetic resonance imaging (CEMRI) showed a heterogeneously enhancing posterior mediastinal mass in pre- and paravertebral region with intraspinal extension in D2-D4 levels. Fluorodeoxyglucose PET/CT showed a metabolically active mass occupying the superior, middle and posterior mediastinum on the left, displacing the trachea and esophagus toward the right side and causing complete collapse of the left lung. Posteriorly the mass was seen destroying the D2-D5 vertebrae with intraspinal extension at D2-D4 level. Metabolically active metastatic disease was seen in pleura, skull, D12 vertebra, right iliac bone and bilateral proximal femorae. Biopsy obtained from lung and adjacent pleura showed features of a round cell tumor positive for NKX 2.2, weak positive for FLI 1 and negative for PAN CK, LCA, Vimentin and TLE-1, suggestive of Ewing sarcoma. Based on these investigations, a diagnosis of EES of posterior mediastinum was made.ConclusionExtraskeletal Ewing sarcoma of posterior mediastinum is a rare and aggressive entity. Management of metastatic EES comprises radiotherapy and systemic chemotherapy which reduces tumor burden and micrometastasis. However, response to treatment in metastatic EES is poorer than in localized disease with overall 5-year survival rates of less than 30%. Fluorodeoxyglucose PET/CT can be a useful tool to accurately detect the extent of local disease in the presence of atelectasic lung for radiotherapy planning as well as evaluating response to therapy.

Rescue computed tomography-guided drainage of a giant mediastinal mature teratoma causing airway obstruction prior to surgical resection: a case report

BackgroundGiant mediastinal mature teratomas may cause airway obstruction or decreased venous return due to the mass effect. Preoperative stabilization of the respiratory and circulatory systems is important for perioperative management to safely perform surgery, including general anesthesia. However, to the best of our knowledge, there are only a few reports regarding the preoperative computed tomography (CT)-guided drainage of mediastinal tumors.Case presentationA 30-year-old woman was admitted to the emergency room with sudden dyspnea. CT findings revealed a giant cystic mass in the anterior mediastinum compressing the trachea and the right main bronchus. The patient was intubated and CT-guided drainage of the fluid content of the cyst was performed to decompress the airway obstruction. Thereafter, the mediastinal tumor was resected during elective surgery and pathologically diagnosed as a mature teratoma.ConclusionsRescue preoperative CT-guided drainage of a giant mediastinal mature teratoma allowed safe general anesthesia and surgery by releasing the airway obstruction.

Formation of a rare curve-shaped thoracolith documented on serial chest computed tomography images: A case report

Thoracolithiasis is a rare benign condition that manifests with one or more small nodules in the pleural cavity. In most cases, it is asymptomatic and found incidentally on chest imaging or during thoracic surgery. The thoracolithiasis formation process is rarely documented. Herein, we present a case of a rare, large, curve-shaped thoracolith, the formation of which was documented on serial computed tomography (CT) images. A 46-year-old male patient who denied any prior systemic disease was evaluated due to intermittent right-sided lateral chest pain lasting for a year. Chest radiography and CT revealed a circumscribed calcified nodule measuring 3.5 mm in the right lower lung lobe. Nodule biopsy revealed fungal infection, which was treated with antifungal medication. After 2 years of follow-up, the patient developed intermittent chest discomfort caused by pleural adhesions, and underwent video-assisted thoracic surgery with pneumolysis. Postoperatively, he developed empyema, which fully resolved with antibiotic therapy. Thereafter, he was followed up at the outpatient clinic and underwent chest CT twice per year. Over time, we observed thickening of the right distal pleura near the lower posterior mediastinum, and several sporadic calcified nodules with gradually increasing intensity, which eventually merged into a single calcified curve-shaped thoracolith measuring approximately 9 cm in length during the 5-year follow-up. This study documented the formation of a rare thoracolith shape observed for the first time.

ASO Visual Abstract: Efficacy and Postoperative Outcomes of Laparoscopic Retrosternal Route Creation for the Gastric Conduit-Propensity Score-Matched Comparison to Posterior Mediastinal Reconstruction.

ASO Visual Abstract: Efficacy and Postoperative Outcomes of Laparoscopic Retrosternal Route Creation for the Gastric Conduit-Propensity Score-Matched Comparison to Posterior Mediastinal Reconstruction.

The efficacy of thoracoscopic surgery for descending necrotizing mediastinitis.

Thoracotomy is a reliable approach for descending necrotizing mediastinitis (DNM), and the use of video-assisted thoracic surgery (VATS), a minimally invasive procedure, has been increasing. However, which approach is more effective for DNM treatment is controversial. We analysed patients who underwent mediastinal drainage via VATS or thoracotomy, using a database with DNM from 2012 to 2016 in Japan, which was constructed by the Japanese Association for Chest Surgery and the Japan Broncho-esophagological Society. The primary outcome was 90-day mortality, and the adjusted risk difference between the VATS and thoracotomy groups using a regression model, which incorporated the propensity score, was estimated. VATS was performed on 83 patients and thoracotomy on 58 patients. Patients with a poor performance status commonly underwent VATS. Meanwhile, patients with infection extending to both the anterior and posterior lower mediastinum frequently underwent thoracotomy. Although the postoperative 90-day mortality was different between the VATS and thoracotomy groups (4.8% vs 8.6%), the adjusted risk difference was almost the same, -0.0077 with 95% confidence interval of -0.0959 to 0.0805 (P = 0.8649). Moreover, we could not find any clinical and statistical differences between the 2 groups in terms of postoperative 30-day and 1-year mortality. Although patients who underwent VATS had higher postoperative complication (53.0% vs 24.1%) and reoperation (37.9% vs 15.5%) rates than those who underwent thoracotomy, the complications were not serious and most could be treated with reoperation and intensive care. The outcome of DNM treatment does not depend on thoracotomy or VATS.

Mediastinal teratoma with double malignant transformation

We report a case of a 65-year-old woman with retrosternal discomfort, dyspnea, and weight loss in whom the computed tomography showed a multicystic mass with fat content and calcified wall in the anterior mediastinum. After surgical resection, pathological examination revealed synchronous primary colorectal adenocarcinoma and primary carcinoid tumor arising in a mediastinal mature cystic teratoma. Treatment with oxaliplatin and capecitabine was instituted, and subsequent checkups showed no evidence of recurrence. Malignant transformation of mature cystic teratoma is a rare complication that occurs in 1–3% of these tumors and consists of a nongerm cell malignant tumor arising from a preexisting mature teratoma. Any of the constituent tissues of a teratoma has the potential to undergo malignant transformation. In case of limited disease, treatment should be surgical. There is no consensus regarding adjuvant treatment, and the existence of a double neoplastic lineage may complicate the choice of chemotherapy treatment.

Beklenmedik bir lokalizasyonda ortaya çıkan primer mediastinal büyük B hücreli lenfoma

Primary mediastinal large B-cell lymphoma (PMLBCL) is a mature aggressive large B-cell lymphoma of putative thymic B-cell origin arising in the mediastinum, with distinctive clinical, immunophenotypic, genotypic, and molecular features. Cases that arise outside the mediastinum are very uncommon. A 27-year-old woman presented with mass which had an extramedullary, extradural component at the right T5-6 foramina indenting to the spinal canal, extending craniocaudally from the middle mediastinum to the level of the aortic hiatus. Pathological examination of the mass revealed atypical lymphoid cells with medium-large size, eosinophilic and clear cytoplasm In our case CD23 and MAL expression with morphological findings supported PMLBCL. PMLBCL may be seen with abnormal localization and clinical presentation. Immunohistochemical profile including MAL is helpful to detect these cases.

Retrocardiac Pneumomediastinum: Description of an Unusual Case and Review of Literature

Retrocardiac pneumomediastinum (RP) is the consequence of air trapping in the inferior and posterior mediastinum. It is characterized by the presence of a right or left para-sagittal infrahilar oval or pyramidal air collection on a chest X-ray. It is usually detected in neonates because of alveolar rupture after invasive ventilation or invasive manoeuvres applied on airways or the digestive tract. A healthy child came to the emergency department (ED) for acute respiratory failure due to viral bronchiolitis when he was 2 months old. Because of his clinical condition, he underwent helmet continuous positive airway pressure (HCPAP). When the condition allowed, he was discharged and sent home. He was re-admitted into the hospital for asthmatic bronchitis 3 months later. A frontal chest X-ray taken during the second hospitalization showed an oval-shaped retrocardiac air lucency not previously detected. Differential diagnosis including digestive and lung malformations was made. Finally, the diagnosis of RP was made. We report an unusual case of retrocardiac pneumomediastinum in a 5-month-old male infant after the application of continuous positive pressure via a helmet. RP presentation after the administration of non-invasive ventilatory support beyond the neonatal age is unusual. Although surgical drainage is curative, conservative treatment can be considered in hemodynamically stable patients.

Suppuration in the adult Lincoln’s highway-surgeon’s dilemma

The carotid sheath enclosing the common carotid artery, internal jugular vein, vagus and the deep jugular lymph nodes continues around the vessels of the superior mediastinum. This sheath formed by the investing fascia, prevertebral fascia and the pre-tracheal fascia is captioned the Lincoln s highway. Suppurative pathology of the Lincoln highway presents as a vertical swelling at the anterior border of the sternomastoid. USG, CT and MRI confirms the diagnosis and prompts surgical intervention and thus prevents intra thoracic spread with its morbidity and mortality.

Thymoma and Thymic Carcinoma: Surgical Resection and Multidisciplinary Treatment

Thymoma and thymic carcinoma are the most common tumors of the anterior mediastinum and a relatively rare type of thoracic cancer. The prerequisite for surgery is clinical staging and operative evaluation, both of which are based on medical imaging. The best strategy for treating a thymic epithelial tumor is surgical resection of the organ and surrounding tissue. Thymectomy modalities vary, including open surgery and minimally invasive surgery, and surgeons have used various innovations to better meet the needs of the procedure; therefore, it is critical to select the appropriate procedure based on the patient's characteristics. Evaluation of resectability is the first step of surgical resection for thymic tumors without distant metastasis. The decision regarding unresectability should be made carefully. During subsequent chemotherapy or chemoradiotherapy, reevaluation of whether an area is resectable or not remains essential. Despite numerous technological advances in the surgical treatment of thymic tumors, several contentious issues remain, including the selection of surgical approaches for difficult cases, the selection of video-assisted thoracoscopic approaches, the evaluation of resectability, minimally invasive surgery for locally advanced thymic tumors, lymphadenectomy in thymic tumors, neoadjuvant therapy for thymic tumors, debulking surgery, and salvage surgery. In solving these problems, the surgeon's judgment, surgical experience, and surgical skills are especially important.

Characterization of Mediastinal Bulky Lymphomas with FDG-PET-Based Radiomics and Machine Learning Techniques.

This study tested the diagnostic value of 18F-FDG PET/CT (FDG-PET) volumetric and texture parameters in the histological differentiation of mediastinal bulky disease due to classical Hodgkin lymphoma (cHL), primary mediastinal B-cell lymphoma (PMBCL) and grey zone lymphoma (GZL), using machine learning techniques. We reviewed 80 cHL, 29 PMBCL and 8 GZL adult patients with mediastinal bulky disease and histopathological diagnoses who underwent FDG-PET pre-treatment. Volumetric and radiomic parameters were measured using FDG-PET both for bulky lesions (BL) and for all lesions (AL) using LIFEx software (threshold SUV ≥ 2.5). Binary and multiclass classifications were performed with various machine learning techniques fed by a relevant subset of radiomic features. The analysis showed significant differences between the lymphoma groups in terms of SUVmax, SUVmean, MTV, TLG and several textural features of both first- and second-order grey level. Among machine learning classifiers, the tree-based ensembles achieved the best performance both for binary and multiclass classifications in histological differentiation. Our results support the value of metabolic heterogeneity as an imaging biomarker, and the use of radiomic features for early characterization of mediastinal bulky lymphoma.

CALML5 is a novel diagnostic marker for differentiating thymic squamous cell carcinoma from type B3 thymoma.

Thymic squamous cell carcinoma and type B3 thymoma are primary neoplasms of the anterior mediastinum that are sometimes difficult to differentiate from one another histologically. However, only a few immunohistochemical markers are available for the differential diagnosis. The purpose of this study was to discover a novel marker for differentiating between thymic squamous cell carcinoma and type B3 thymoma. We used histological samples of thymic carcinomas (n=26) and type B3 thymomas (n=38) which were resected between 1986 and 2017. To search for candidates of differential markers, gene expression levels were evaluated in samples using promoter analysis by cap analysis of gene expression (CAGE) sequencing. Promoter level expression of CALML5 genes was significantly higher in thymic carcinomas than in type B3 thymomas. We further validated the results of the CAGE analysis in all 26 thymic carcinomas and 38 type B3 thymomas by immunohistochemistry (IHC). CALML5 was strongly expressed in the cytoplasm in 19 of 26 cases with thymic carcinoma, whereas positivity at the protein level was shown in two of 38 type B3 thymomas. Thus, the sensitivity (73.1%) and specificity (94.7%) of CALML5 as markers for immunohistochemical diagnosis of thymic carcinoma were extremely high. We identified CALML5 as a potential marker for differentiating thymic squamous cell carcinoma from type B3 thymoma. It is assumed that future clinical use of CALML5 may improve the diagnostic accuracy of differentiating between these two diseases.

Three cases involving ablation of incompletely resected lesions during resection of middle mediastinum cysts

中縦隔発生囊胞の摘出術では，周囲組織との強固な癒着により完全切除が困難で，再発が危惧される場合がある．2008年9月から2020年10月までに当院で外科的治療を施行した中縦隔発生囊胞7例のうち，残存囊胞壁に対して焼灼を行った3例を提示する．不完全切除症例は男性1例，女性2例，平均年齢は57歳であった．病理診断では気管支原性囊胞2例，起源不明囊胞1例．全例胸腔鏡下縦隔囊胞切除術が行われ，残存囊胞壁に対しエネルギーデバイスによる焼灼を施行した．3例では観察期間内に再発は認めなかった．術後長期的な経過を観察出来ていないが，中縦隔発生囊胞の残存病変に対する処置の1つとして囊胞壁へのエネルギーデバイスによる焼灼は再発を予防できる可能性があると考えたため報告する．

Sestamibi-guided thoracoscopic excision of functional mediastinal parathyroid adenoma in a child: A case report and review of literature.

Primary hyperparathyroidism secondary to ectopic parathyroid (in anterior mediastinum) is rare in children. We report the case of a 12-year-old girl with a history of multiple fractures, renal calculi and limb deformities. She was diagnosed with hyperparathyroidism secondary to an intrathymic parathyroid adenoma. Sestamibi scan showed a lesion in the anterior mediastinum. A biochemical evaluation revealed hypercalcaemia, elevated alkaline phosphatase and parathormone levels. The lesion was marked with radioisotope and confirmed intraoperatively using a gamma camera. The child underwent thoracoscopic left thymectomy with the adenoma. Immediate decrease in calcium and parathyroid hormone values were noted intraoperatively and serial monitoring showed a downward trend. On follow-up, the child is doing well. Ectopic parathyroid adenoma is very rare. CT with radioisotope scans is helpful in diagnosis. Thoracoscopic excision of ectopic adenoma is safe in children.

Successful surgical treatment of mediastinal lung hernia with a mesh implant. Consequent results

An observation from practice is given – surgical treatment of mediastinal pulmonary hernia in a patient after pneumonectomy using the method of anterior mediastinal plastic surgery with a mesh implant with demonstration of long-term results.The patient I. 31 years old was ill with pulmonary tuberculosis for 3 years, treatment was carried out, against which the stenosis of the left main bronchus progressed. The patient underwent endoscopic operations: argonoplasmic destruction of the left main bronchus, balloon dilation of the left main bronchus, with a temporary effect. Due to recurrent stenosis of the left main bronchus, a pneumonectomy was performed on the left. After 7 months, she complained of severe shortness of breath at rest. Computed tomography revealed a displacement of the mediastinal organs to the left, an upper-anterior pulmonary mediastinal hernia of the right lung to the left midclavicular line at the level of the anterior I-IV intercostals on the left. The patient underwent plastic surgery of the anterior mediastinum on the right using a polymer mesh implant. As a result of treatment, after 3 years, radiologically stable restoration of the position of the only right lung in its hemithorax. The patient is functionally compensated, shortness of breath is not observed. The patient has completely returned to her usual lifestyle.

Nomogram based on TNM stage to predict the prognosis of thymic epithelial tumors (TETs) patients undergoing extended thymectomy.

Thymomas and thymic carcinoma are thymic epithelial tumors (TETs) of the anterior mediastinum. On the basis of The AJCC 8th Edition of TNM classification, no prognostic prediction model has been established for TETs patients undergoing surgical resection. In this study, based on data from Qilu Hospital of Shandong University, we identified prognostic factors and developed a nomogram to predict the prognosis for TETs patients undergoing extended thymectomy. Patients with TETs who underwent thymectomy between 2010 and 2020 were consecutively enrolled. An analysis of multivariate Cox regression and stepwise regression using the Akaike information criterion (AIC) was conducted to identify prognostic factors, and a nomogram for TETs was derived from the results of these analyses. The model was validated internally with the Kaplan-Meier curves, ROC curves and calibration curves. There were 350 patients with TETs enrolled in the study, and they were divided into a training group (245,0.7) and a validation group (105,0.3). Age, histological type, tumor size, myasthenia gravis, and TNM stage were independent prognostic factors for CSS. The Kaplan-Meier curves showed a significant difference between high nomorisk group and low nomorisk group. A nomogram for CSS was formulated based on the independent prognostic factors and exhibited good discriminative ability as a means of predicting cause-specific mortality, as evidenced by the area under the ROC curves (AUCs) of 3-year, 5-year, and 10-year being 0.946, 0.949, and 0.937, respectively. The calibration curves further revealed excellent consistency between the predicted and actual mortality when using this nomogram. There are several prognostic factors for TETs. Based on TNM stage and other prognostic factors, the nomogram accurately predicted the 3-, 5-, and 10-year mortality rates of patients with TETs in this study. The nomogram could be used to stratify risk and optimize therapy for individual patients.