Primary mediastinal tumors. Part 1: tumors of the anterior mediastinum

Spontaneous rupture of a cystic mediastinal teratoma complicated by superior vena cava syndrome

Spontaneous rupture of cystic mediastinal teratomas is rare but may cause serious complications. Here we report an unusual case of a cystic teratoma, which ruptured into the mediastinal and pleural cavities resulting in superior vena cava syndrome, acute mediastinitis, and pleural effusion. Early diagnosis and prompt surgical treatment of ruptured mediastinal teratomas are essential to preventing life-threatening complications.

Proposal for a new mediastinal compartment classification of transverse plane images according to the Japanese Association for Research on the Thymus (JART) General Rules for the Study of Mediastinal Tumors

There is no existing worldwide published method for mediastinum compartment classification based on transverse section images for the differential diagnosis of mediastinal tumors. Herein, we describe a new method for anatomic mediastinal compartment classification using transverse section computed tomography (CT) images and the use of this method to classify mediastinal lesions, and thus evaluate whether the method is sufficiently user-friendly and useful. In a publication of the Japanese Association for Research on the Thymus (JART), we proposed the following four mediastinal compartments based on transverse CT images: superior portion of mediastinum, anterior mediastinum (prevascular zone), middle mediastinum (peri-tracheoesophageal zone), and posterior mediastinum (paravertebral zone). In the present study, we retrospectively analyzed 445 pathologically proven mediastinal mass lesions, and categorized them into the proposed four compartments by consensus reading. Mass lesions were classified into compartments based on the location of the lesion centroid, and each lesion was satisfactorily categorized into a compartment. Almost all thymic epithelial tumors (99%, 244/246), all 24 thymic malignant lymphomas and a majority of germ cell neoplasms (93%, 54/58) were classified as being in the anterior mediastinum compartment. The majority of intrathoracic goiters (82%, 14/17) were categorized as being in the superior portion of the mediastinum compartment. Approximately two-thirds of mass lesions in the middle mediastinum were cysts, including foregut and pericardial cysts. Approximately 80% of 37 mass lesions in the posterior mediastinum were neurogenic tumors. Correspondingly, 29 of the 49 neurogenic tumors (60%) were categorized as being in the posterior mediastinum, while 10 (20%) were in the superior portion of the mediastinum, 4 (8%) in the anterior mediastinum, and 6 (12%) in the middle mediastinum. Our findings showed that the newly proposed mediastinal compartment classification using transverse images appears to be user-friendly enough for practical clinical application and may be helpful in differential diagnoses.

Diffusion-weighted MR imaging vs. multi-detector row CT: Direct comparison of capability for assessment of management needs for anterior mediastinal solitary tumors

PURPOSE

To evaluate and compare the capability of diffusion-weighted MR imaging (DWI) and CT for assessment of management needs for anterior mediastinal solitary tumors.

MATERIALS AND METHODS

Thirty-five patients with pathologically confirmed anterior mediastinal tumors were enrolled. The tumors were divided into two groups according to need for management: tumors not needing further intervention or treatment (group A; thymoma type A, AB and B1) and tumors needing further intervention and treatment (group B; other thymoma types and malignancies). The apparent diffusion coefficient (ADC) of each tumor was measured, and probabilities of malignancy and need for further intervention and treatment were visually assessed on CT. The differences in ADCs between group A and B and between malignancies and thymomas in group B were evaluated with the Mann-Whitney's U-test. Feasible threshold values for differentiation of group B from group A and distinguishing malignancies from thymomas assessed as group B were determined by the ROC-based positive test, and McNemar's test was used for comparing diagnostic capabilities of DWI with those of CT.

RESULTS

ADCs for the two groups were significantly different (p<0.001). Application of the threshold value for differentiation of group B from A showed no significant difference (p>0.05). Application of the feasible threshold value for distinguishing malignant from thymomas assessed as group B showed that specificity (76.9%) and accuracy (85.2%) of DWI were significantly better than those of visual score (p<0.05).

CONCLUSION

DWI has useful potential for the assessment of management needs for anterior mediastinum solitary tumors as well as CT.

Thymic carcinoma developing in a multilocular thymic cyst

Thymic carcinoma developing in a pre-existing thymic cyst has rarely been reported in literature. The diagnosis of this entity in the past has always been established after surgery. We are reporting a case of thymic carcinoma that developed in a pre-existing multilocular thymic cyst in an elderly male. The diagnosis was based on imaging findings and confirmed on fine needle aspiration cytology (FNAC).

Additional value of dual-energy CT to differentiate between benign and malignant mediastinal tumors: an initial experience

OBJECTIVES

To investigate the feasibility of dual-energy computed tomography (DECT) in differentiating malignant from benign mediastinal tumors.

MATERIALS AND METHODS

We prospectively enrolled 25 patients (14 males; mean age: 56.7 years) who had suspected mediastinal tumors on chest radiography or non-contrast chest computed tomography (CT). All patients underwent a two-phase DECT using gemstone spectral imaging (GSI) mode (GE HD750). For the quantitative analysis, two investigators measured the following parameters of the tumors in the early and the delayed phases: CT attenuation value in Hounsfield units (HU) and iodine concentration (mg/ml). Pathological results were used for a final diagnosis. Statistical analyses were performed using the Fisher's exact test and the Mann-Whitney t-test.

RESULTS

10 patients (40%) had benign pathology, while 15 (60%) had malignant pathology. The iodine concentration measurements were significantly different between benign and malignant tumors both in the early phase (1.38 mg/ml vs. 2.41 mg/ml, p=0.001) and in the delayed phase (1.52 mg/ml vs. 2.84 mg/ml, p=0.001), while mean attenuation values were not significantly different in both phases (57.8 HU vs. 69.1 HU, p=0.067 and 67.4 HU vs. 78.4 HU, p=0.086, respectively).

CONCLUSIONS

Dual-energy CT using a quantitative analytic methodology can be used to differentiate between benign and malignant mediastinal tumors.

Benign mediastinal teratoma with intrapulmonary and bronchial rupture presenting with recurrent hemoptysis

Mediastinal teratomas are usually asymptomatic tumors, located most commonly in the anterior mediastinum. Very rarely, such tumors may rupture into the tracheobronchial tree, lung, pleura or pericardium. Computed Tomography (CT) is helpful in the diagnosis and differentiation of ruptured and unruptured tumors.

We report a case of ruptured anterior mediastinal teratoma in a 20-year-old female presenting with recurrent hemoptysis and cough; thus, mimicking a lung malignancy or tuberculosis. CT demonstrated a heterogeneous fat containing lesion in the anterior mediastinum with extension into the lingular lobe. Subsequent fine needle aspiration cytology (FNAC) yielded plenty of anucleate squames and debris, and a clear cut diagnosis could not be made. Total excision of the tumor was performed and histopathology of the surgically excised mass confirmed the CT diagnosis.

Thymic neoplasm: a rare disease with a complex clinical presentation

Thymic neoplasms constitute a broad category of rare lesions with a wide spectrum of pathologic characteristics and clinical presentations which therefore require a high index of suspicion to diagnose. The natural history of the disease is seldom predictable, anywhere from an indolent to an aggressively malignant course. Although the classification and staging of these lesions are complex and controversial, complete radical surgical resection remains the gold standard of therapy. Radiation and chemotherapy are important elements of the multimodality approach to treating these patients and it is important for thoracic surgeons to work closely with their colleagues in other disciplines in the management of and future research endeavors in thymic neoplasm. In this review, we discuss the evaluation of the patient with an anterior mediastinal mass, the classification and staging of thymic neoplasms, the role of surgery, radiation and chemotherapy in treating this disease, as well as future directions in research for novel targeted therapies.

A case of invasive thymoma with endotracheal polypoid growth

Thymomas are one of the most common neoplasms of the mediastinum derived from thymic epithelium. It is common that invasive thymoma invades the lung, pericardium, and great vessels. Airway compression by mass effect also occurs, but direct polypoid tumor growth into the airway is extremely rare. Only 20 cases of invasive thymoma with endobronchial polypoid growth have previously been reported globally. However, there is no case report of invasive thymoma with endotracheal growth. Herein, we report a rare case of invasive thymoma with endotracheal polypoid growth in a 28-year-old woman.

Massive pericardial effusion and multiple pericardial masses due to an anterior mediastinal teratoma rupturing in pericardial sac

A 25 -year-old Egyptian man presented to our unit for the evaluation of a large pericardial effusion. At 1 month before presentation he suffered from daily bouts of fever. Chest x-ray revealed cardiomegaly, echocardiography showed large pericardial effusion and multiple pericardial masses. Needle pericardiocentesis revealed a bloody exudate with no malignant cells. Chest CT showed a well-circumscribed anterior mediastinal cystic mass with a central fat component and foci of calcification. MRI of the chest similarly showed no intracardiac extension. A cystic mass 7×9 cm was removed via a median sternotomy with uneventful postoperative course. Pathological evaluation revealed a benign cystic teratoma and a thymic cyst. Most cystic teratomas are accidentally discovered, large ones can cause symptoms through the compression of mediastinal structures or rupture in pericardial sac.

Thymic neoplasms: a clinical update

Thymoma is a unique neoplasm of the anterior mediastinum that is frequently associated with indolent growth and a variety of paraneoplastic syndromes. One third of cases are detected during the evaluation of myasthenia gravis. Classification systems of thymoma have limited ability in accurately predicting prognosis and course of disease. Thus, staging is the only way to predict clinical behavior. Encapsulated tumors that are surgically resected carry the best prognosis. Adjuvant radiotherapy is recommended for incompletely excised and most invasive thymomas. Chemotherapy in anthracycline-based chemotherapy remains the most effective chemotherapy for neoadjuvant, adjuvant or palliative treatment.

Asymptomatic thymic cyst appearing in the neck on valsalva: unusual presentation of a rare disease

Thymic cysts are usually diagnosed accidentally during radiological evaluation of the chest for unrelated conditions. Symptoms appear late when the mass compresses on adjoining tissues. We report an unusual case of asymptomatic mediastinal thymic cyst which was seen in the neck whenever the patient was asked to perform Valsalva maneuver. This case is being reported for the unusual clinical presentation of a rare disease. The role of imaging in the diagnosis and common differential diagnoses are also discussed.

[Management of anterior mediastinal masses in adults]

The discovery of an anterior mediastinal mass requires careful management with specific consideration of the pathology. More than 50% of all mediastinal masses seen in adults are in the anterior mediastinum. The most frequent diagnoses are thymoma, lymphoma, teratoma and benign thyroid tumours. 60% of cases are malignant. Often the clinical and radiological findings do not allow a definitive diagnosis and a histological diagnosis is often required to select the optimal treatment modality. The choice of biopsy technique depends on the localization of the lesion, clinical factors, and the availability of special techniques and equipment. Biopsy may be obtained by trans-thoracic puncture under computed tomography or ultrasound guidance, or by a surgical approach (mediastinotomy or thoracoscopy).

An unusual cause of chest pain in a young woman

A 25-year-old-woman presented to health-care services recurrently due to pleuritic chest pain. This increased during the first trimester of her first pregnancy. She was subsequently referred to a tertiary cardiology centre where she was seen by a cardiologist with a special interest in obstetric cardiology. After further investigations, an unusual cause of her pain was identified. Her investigations, management and her clinical course are presented here.

Infected tracheal diverticulum mimicking an aggressive mediastinal lesion on FDG PET/CT: an interesting case with review of the literature

The differential diagnosis for intense hypermetabolic mediastinal lesions on positron emission tomography (PET) could benefit from the combined morphological and metabolic information present in a fluorodeoxyglucose (FDG) PET/CT study. We report a case of an infected tracheal diverticulum mimicking an FDG-avid malignancy in a patient with a history of chronic lymphoproliferative disease. We review the literature for a systematic approach in the differential diagnosis of cystic mediastinal lesions. The embryological development of the normal tracheobronchial tree is reviewed, followed by a presentation of various congenital and acquired mediastinal lesions. The characteristic CT findings are described for each lesion and the avidity for FDG on PET is mentioned when references are available. This case emphasises that complicated benign processes should be considered in the differential diagnosis of an FDG-avid mediastinal lesion, even in subgroups of patients with significant risk factors for malignancy.

Mediastinal endodermal sinus tumor associated with fatal hemophagocytic syndrome

The association of endodermal sinus tumor, known also as yolk sac tumor, of the mediastinum with hemophagocytic syndrome is exceedingly rare with only a few cases on record. We report a 24-year-old male who had a large mediastinal germ cell tumor, proven to be an endodermal sinus tumor on biopsy. The patient developed pancytopenia and coagulopathy related to associated hemophagocytic syndrome, with a fatal outcome. A brief review of the relevant literature is presented as well.

Thymic malignancies: from clinical management to targeted therapies

PURPOSE

A key challenge in the treatment of thymoma and thymic carcinoma (TC) is in improving our understanding of the molecular biology of these relatively rare tumors. In recent years, significant efforts have been made to dissect the molecular pathways involved in their carcinogenesis. Here we discuss the results of large-scale genomic analyses conducted to date and review the most active chemotherapies and targeted treatments.

METHODS

We reviewed the literature for chemotherapeutic trials in the last 20 years and trials involving targeted therapies between 1999 and 2010. The search was supplemented by a review of abstracts presented at the annual meetings of the American Society of Clinical Oncology (from 1999 to 2010), at the first International Conference on Thymic Malignancies in 2009, and at a follow-up meeting of the newly formed International Thymic Malignancies Interest Group in 2010.

RESULTS

Surgery remains the treatment of choice for operable tumors, whereas chemotherapy is standard in locally advanced and metastatic disease. Thus far, targeted therapies have been developed empirically. Histone deacetylase inhibitors have shown some activity in thymoma whereas sunitinib may be active in TC. There are no data to support the use of HER2- or EGFR-targeted therapies in thymic malignancies.

CONCLUSION

Drug development for the treatment of thymic malignancies is difficult because of the rarity of these tumors. Ethnic differences are becoming apparent, with aggressive subtypes being observed in Asians and African Americans. Incremental improvements in our understanding of tumor biology suggest that molecular profiling-directed therapies may be the preferred route of investigation in the future.

Thymoma calcification: is it clinically meaningful?

Among anterior mediastinal lesions, thymoma is the most common. Thymomas are tumors of thymic epithelial cell origin that are distinguished by inconsistent histological and biologic behavior. Chest imaging studies typically show a round or lobulated tumor in the anterior mediastinum. Calcifications in thymomas are classically punctuate or amorphous, positioned within the lesion. Chest computed tomography (CT) features suggesting higher risk thymoma consist of tumor heterogeneity, vascular involvement, lobulation, pulmonary nodules, lymphadenopathy, and pleural manifestations. Imaging findings have an imperfect ability to predict stage and prognosis for thymoma patients. Our objective is to highlight the clinical implications of thymoma calcifications on the diagnosis, clinical manifestation and prognosis. A pubmed and google search was performed using the following words: thymoma calcification, calcified thymus, mediastinal calcification, anterior mediastinal calcification, and calcified thymoma. After reviewing 370 articles, 32 eligible articles describing thymoma calcifications were found and included in this review. Although the presence of thymus calcifications was more common in patients with invasive thymomas, they were present in significant portion of non-invasive thymomas. The presence of calcifications was not a significant factor in differentiating between benign and malignant thymoma. As a result, the type, location, size or other characteristics of thymus gland calcifications were not relevant features in clinical and radiologic diagnosis of thymoma. The histopathological diagnosis is still the only possible way to confirm the neoplastic nature of thymoma. All types of thymomas should be evaluated and managed independently of the presence of calcifications.

Mediastinal schwannoma diagnosed by endoscopic ultrasonography-guided fine needle aspiration cytology

Schwannoma is the most common neurogenic tumor that is derived from the peripheral nerve sheath. There are no specific serologic markers or characteristic imaging abnormalities associated with schwannoma. Tissue diagnosis and immunohistochemistry are required to diagnose this lesion. We describe a 65-year-old male with a finding of three mass lesions in the superior and middle mediastinum on computed tomography of the chest. The largest lesion measured 4.6 × 5 cm. The patient subsequently underwent endoscopic ultrasonography-guided fine needle aspiration (EUS-FNA) of the lesion and cytology was consistent with spindle cell neoplasm. Immunohistochemical staining of the cytologic specimen was positive for S-100 and negative for pan-cytokeratin, CD34, CD117, calcitonin, smooth muscle actin and desmin. These findings were consistent with schwannoma. This is the second reported case of a mediastinal schwannoma diagnosed by EUS-FNA.

Thymic carcinoma with primary spine metastasis

Thymic carcinomas (TC) are rare tumors, representing 0.2% to 1.5% of all malignancies, with extrathoracic metastases to liver, kidney and bone occurring in 1% to 15% of patients. Although TC exhibit highly aggressive biological behavior, spinal metastasis with cord compression is rare. We describe a 57-year-old man with a 2-month history of cervicodorsal pain diagnosed with TC with primary spinal metastasis. We conclude that TC should be considered in the differential diagnosis in patients who have developed spine metastatic tumors. Early detection and appropriate surgical treatment can lead to preservation of spinal stability and neurologic improvement.

Anterior mediastinal mass: a rare presentation of tuberculosis

We report a case of a 14-year-boy who presented to us with a low-grade fever with evening rise for 9 months. Along with this, the patient also reported a reduction in his appetite and body weight. He had a mild dry cough but no respiratory symptoms otherwise. There was no other localization for fever on history. He received antitubercular therapy, based on abnormal chest radiograph. However, there was no relief in his symptoms. General physical examination revealed mild fever. Systemic examination was unremarkable. Blood investigations done for fever were noncontributory. Computed tomographic (CT) scan of the chest revealed a mediastinal mass compressing the trachea. The possibilities of lymphoma or germ cell tumour were considered. A biopsy from the mass under CT guidance was performed. The histopathology revealed multiple epithelioid cell granulomas with necrosis, and the diagnosis of tuberculosis was made. The clinical course of this patient and the relevant literature is presented in this paper.

Tumors of the mediastinum and chest wall

Primary tumors of the mediastinum and chest wall comprise a diverse group of conditions with a wide range of presentations. A thorough knowledge of thoracic anatomy is essential for appropriate diagnosis and treatment. Given their proximity to critical structures, treatment of these tumors is often challenging. Although surgery is the mainstay of therapy for most mediastinal and chest wall tumors, a multidisciplinary approach is valuable in many cases.

An unusual cause of a mediastinal mass

Primary hyperparathyroidism (PHPT) is a disorder resulting in hypercalcaemia due to autonomous over secretion of parathyroid hormone. Mediastinal parathyroid adenoma is a rare disorder which can present with a widened mediastinum on a plain film. Its always important to check calcium level in patients who present with a mediastinal mass to rule out PHPT. Recognition of this disorder is crucial to prevent long-term sequelae. The authors report an interesting case and discuss further about it, which would be of help both to a specialist and a general physician.

Huge mediastinal cystic tumor penetrating the sternum

We report a very rare case of a huge anterior mediastinal tumor penetrating the sternum that was diagnosed in a 59-year-old woman. The tumor was completely resected en bloc with the manubrium sterni, and the chest wall defect was closed with a pectoralis major muscle flap. Histologic examination of the cystic mass revealed the diagnosis of a benign mediastinal cystic tumor, most likely a benign cystic mature teratoma.

Nonseminomatous germ cell tumor with seizure disorder and mental retardation

We report a case of a patient who presented with anterior mediastinal mass, seizure disorder, and mental retardation. Computerized tomography-guided fine-needle aspiration biopsy of the mass showed nonseminomatous germ cell tumor. Chromosomal analysis showed XXY karyotype. A diagnosis of Klinefelter syndrome and mediastinal germ cell tumor was made.

Assessment of mediastinal tumors with diffusion-weighted single-shot echo-planar MRI

PURPOSE

To assess the role of diffusion-weighted single-shot echo-planar magnetic resonance imaging (MRI) in patients with mediastinal tumors.

METHODS

Prospective study was conducted on 45 consecutive patients (29 male, 16 female, age 22-66 years, mean 41 years) with mediastinal tumor. They underwent diffusion-weighted single-shot echo-planar MRI of the mediastinum with a b-factor of 0, 300, and 600 sec/mm(2). The apparent diffusion coefficient (ADC) value of the mediastinal tumor was correlated with the histopathological findings.

RESULTS

The mean ADC value of malignant mediastinal tumors was 1.09 +/- 0.25 x 10(-3) mm(2)/sec, and of benign tumors was 2.38 +/- 0.56 x 10(-3) mm(2)/sec. There was a significant difference in the mean ADC value between malignant and benign tumors (P = 0.001) and within different grades of malignancy (0.001). When an ADC value of 1.56 x 10(-3) mm(2)/sec was used as a threshold value for differentiating malignant from benign tumor, the best results were obtained with an accuracy of 95%, sensitivity of 96%, specificity of 94%, positive predictive value of 94%, negative predictive value of 96%, and area under the curve of 0.938.

CONCLUSION

The ADC value is a noninvasive parameter that can be used for differentiation of malignant from benign mediastinal tumors and grading of mediastinal malignancy.

Mediastinal teratoma with malignant degeneration

Here, we report the case of a patient with a slowly-progressing anterior mediastinal teratoma submitted to surgical resection. The anatomopathological examination of the sample revealed malignant degeneration to carcinoid tumor. Such evolution is very rare, and we have found only three related studies in the literature. We describe the clinicopathological features of the tumor and discuss the treatment administered. The evolution was satisfactory, and the patient was submitted to oncological treatment.

Sonographic management of mediastinal syndrome

INTRODUCTION

Mediastinal syndrome is suspected on the basis of clinical symptoms and is generally confirmed by chest radiography or computed tomography (CT). However, also grey scale ultrasound (US) and contrast enhanced US (CEUS) are useful in this hematologic emergency as they provide the possibility to perform US-guided biopsy and histological diagnosis.

MATERIALS AND METHODS

15 Patients affected by mediastinal syndrome were prospectively studied using B-mode US and CEUS; 13 of these patients, who had no other lesions, were proposed for US-guided biopsy of the mediastinal mass, but only in 12 patients biopsy was technically possible.

RESULTS

In this study, B-mode US reached an excellent sensitivity (100%) in evidencing the lesions but a low specificity which did not exceed 30-40%. CEUS reached an elevated specificity identifying neoplastic pathologies if both the early and the late phases are considered (90-86.6%). US-guided biopsy was possible in 92.3% of lesions showing a diagnostic adequacy of 91.66%.

CONCLUSIONS

B-mode US associated with CEUS and US-guided biopsy reached an elevated accuracy in the diagnosis of mediastinal masses. If these results are confirmed by further studies, this diagnostic procedure could be included in the routine management of mediastinal syndrome.

Multimodality treatment of germ cell tumors of the mediastinum

Germ cell tumors originating in the anterior mediastinal compartment represent a rare but biologically interesting group of neoplasms. Knowledge of the specific biologic behaviors and therapeutic strategies for the three histologic types is important. PMNSGCT represent the most challenging group of malignant germ cell tumors and survival outcome is dependant on both successful chemotherapy and surgery to remove residual disease when feasible. The authors currently believe nonbleomycin-containing regimens will reduce operative risks in this regard. New chemotherapy strategies that reduce the incidence of persistent nonseminatous germ cell or non-germ cell cancer need continued investigation. Although overall survival is inferior to nonseminomatous germ cell tumors of testicular origin, favorable subsets with pathologic evidence of either necrosis or teratoma have been identified. An aggressive surgical approach after cisplatin-based chemotherapy can result in long-term survival, even in patients with persistent nonseminomatous germ cell or non-germ cell cancer, and is warranted in these otherwise young and healthy patients.

Intraoperative strategy in patients with extended involvement of mediastinal structures

The mediastinum is a virtual space containing several vital organs and structures. Biopsy and resection of lesions located within this region often require several considerations that bear on intraoperative strategy. To optimize outcome, clinicians must be able to predict which patients are at highest risk of anesthetic complications. Superior vena cava involvement, extensive compression of the airway, and pericardial effusion have a clear impact on the decision-making of the anesthetist and surgeon, who should plan together when forming the surgical strategy.

[Computerized tomography of mediastinal tumors]

Tumors of the mediastinum represent a very heterogeneous group of primary and metastatic tumors. Most tumors of the mediastinum are detected on chest radiography, but for more precise view additional imaging methods are necessary. The most common causes of tumor mass in anterior mediastinum are thymoma, germ cell tumors, retrosternal goitre and Hodgkin's lymphoma. In the middle mediastinum most commonly tumors are congenital cysts, such as bronhogenic and pericardial cysts, and enlarged lymph nodes, while in the posterior mediastinum dominantly present neurogenic tumors. Complex anatomy of mediastinum infrequently makes difficulties in radiological diagnosis of these tumors. Computerized tomography (CT) is a radiological method of choice in the diagnosis of primary and/or secondary mediastinal lesions. Localization and structure of the tumor masses are very important for diagnosis. Knowledge of anatomy, with the standard topographic divisions on the anterior, middle and posterior mediastinum is necessary prerequisite for a valid CT diagnostic. Lesions in all parts of the mediastinum are systematically presented from the aspect of practical recommendations, with a view of the typical pathological findings.