Mediastinal masses

Proton Beam Therapy for Unresectable Mediastinal and Pericardial Spindle Cell Sarcoma: A Case Report

Unresectable mediastinal soft tissue sarcomas are often aggressive and associated with a poor prognosis. A 17-year-old male presented with progressive fatigue, shortness of breath, and heart palpitations secondary to an extensive mass involving the mediastinum and pericardium. He was treated with chemotherapy per protocol Children's Oncology Group Protocol ARST0332 and proton beam therapy to the involved mediastinum, pericardium, and heart. At the 5-year follow-up evaluation, he remained disease-free on surveillance imaging. An echocardiogram revealed a 55% to 60% left ventricular ejection fraction. Given the patient's extended survival, we present the oncologic rationale for treatment and considerations of late toxicity.

Mesenchymal Tumors of the Mediastinum: An Update on Diagnostic Approach

Mesenchymal tumors of the mediastinum are a heterogenous group of rare tumors with divergent lineages. Mediastinal mesenchymal tumors are diagnostically challenging due to their diversity and morphologic overlap with nonmesenchymal lesions arising in the mediastinum. Accurate histologic diagnosis is critical for appropriate patient management and prognostication. Many mediastinal mesenchymal tumors affect distinct age groups or occur at specific mediastinal compartments. Neurogenic tumors, liposarcoma, solitary fibrous tumor, and synovial sarcoma are common mesenchymal tumors in the mediastinum. Herein, we provide an update on the diagnostic approach to mediastinal mesenchymal tumors and a review of the histologic features and differential diagnosis of common benign and malignant mesenchymal tumors of the mediastinum.

Primary Intrathoracic Sarcomas: A Review of Cross-sectional Imaging and Pathology

The most common sarcomas in the thorax are metastasis from an extrathoracic primary malignancy. Primary intrathoracic sarcomas are rare albeit aggressive malignancies that are diagnosed on histopathology. Although a few imaging characteristics have been described that are common to sarcomas, it is still a diagnosis of exclusion as other tumors are much more common. Like elsewhere, primary thoracic sarcomas are also classified according to their histologic features. They are a rare group of tumors that can arise from the mediastinal structures, lung, pleura, or chest wall. On imaging, differentiating these from more common malignancies like lung cancer is difficult and often requires multimodality workup and tissue sampling. A few sarcomas are very specific to their locations, such as angiosarcoma in the right atrium, leiomyosarcoma in the pulmonary artery, where imaging has high accuracy for the diagnosis. Despite being nonspecific in a majority of cases, imaging plays a pivotal role in determining the organ of origin, tumor extent, invasion of adjacent structures, and thus help to assess the surgical resectability. Although sarcomas arising from chest wall are the most common primary sarcomas in the chest, they are excluded from this review to focus only on primary intrathoracic sarcomas. The article provides a comprehensive imaging and pathology review of the rare primary intrathoracic sarcomas, including but not limited to angiosarcoma, Kaposi sarcoma, fibrosarcoma, malignant transformation of fibrous tumor of pleura, sarcomatoid mesothelioma, leiomyosarcoma, and malignant small round blue cell tumors.Key points:Primary intrathoracic sarcomas are rare but clinically important.Imaging helps to determine local extent, invasion, metastases and appropriate site/mode of biopsy.Role of pathology is paramount in diagnosis and guiding treatment based on immunogenetic/molecular typing.

Epidemiology of childhood malignant mediastinal masses and clinical factors associated with intensive care unit admission: A Singapore experience

AIM

Majority of mediastinal masses in children are malignant. These masses are complex to manage as they have a risk of compression to surrounding structures. Many of these children have to be managed in the intensive care unit (ICU). Hence we sought to evaluate the local epidemiology of malignant mediastinal masses in children and their clinical presentation, and identified factors associated with ICU admission so that at-risk patients may be identified early.

METHODS

This study is a retrospective review of institutional case records of 56 children below 18 years of age from 2000 to 2015 with a malignant mediastinal mass. We collected data on their presenting symptoms, clinical signs, radiological investigations, treatment and correlated these factors with admission to our ICU.

RESULTS

Lymphoma was most common diagnosis, comprising 37 children (66.0%). There were 6 patients with neuroblastoma (10.7%), 3 patients with germ-cell tumour (5.4%) and 10 patients with T-cell acute lymphoblastic leukaemia (17.9%). Overall, 21 patients (37.5%) had to be admitted to the ICU. Almost all patients (98.2%) were symptomatic on presentation, of which lymphadenopathy was the most common (69.6%). Factors that are significantly associated with ICU admission are stridor, pericardial effusion and need for pleural drainage.

CONCLUSIONS

Malignant mediastinal masses in children in our institution range from leukaemias and lymphomas to germ cell tumours and neuroblastomas, of which almost all are symptomatic. These children have a risk of cardiorespiratory collapse and many of them require intensive care. We identified factors that are associated with ICU admission, with the aim of early intervention of at-risk cases.

A case of mediastinal teratoma with pancreatic islets accompanied by discontinuation of insulin treatment in insulin-dependent diabetes mellitus

A 74-year-old woman of insulin-dependent diabetes mellitus presented with gradually improvement of blood glucose control and finally discontinuation of insulin therapy, for some unknown reason. During follow-up period, she was admitted with hemoptysis. CT imaging showed a heterogeneous enhancement mass in the middle mediastinum with cyst and calcification, suggesting the diagnosis of mediastinal teratoma. Immediately after excision of the tumor, her plasma glucose levels again increased, and she required insulin therapy for glycemic control. Immunohistochemical examination showed that the tumor contained pancreatic tissue with both exocrine and endocrine components consisted with the islet cells of Langerhans with insulin-positive cells. Accordingly, we diagnosed insulin-producing mediastinal teratoma. Although hypoglycemic agents are the commonest cause of hypoglycemia in diabetic patients, an insulin-producing tumor should be considered in the patients who have dramatic improvement of diabetes mellitus, particularly after withdrawal of all hypoglycemic treatment. Mediastinal teratomas should be considered in differential diagnosis as etiology in undiagnosed case of hypoglycemia or blood glucose fluctuations.

A Case of Primary Mediastinal Leiomyosarcoma in Which Long-Term Survival Was Achieved

INTRODUCTION

Primary leiomyosarcomas (LMS) of the mediastinum are extremely rare malignant mesenchymal tumors developing from soft tissues or great vessels. We present a case of a primary leiomyosarcoma of the middle mediastinum in which long-term survival was achieved.

CASE REPORT

A 77-year-old man presented to us for examination with an extrapleural sign in his upper mediastinum on chest X-ray. Computed tomography (CT) revealed a well-circumscribed mass in the middle mediastinum. Thoracoscopic resection of the mediastinal tumor and immunohistological findings, which were positive for smooth muscle actin (SMA), HHF-35, vimentin, and desmin confirmed primary leiomyosarcoma. It recurred twice with solid right pulmonary metastases, which were resected. He was followed-up for a total of 9 years and 6 months from the first surgery with no signs of recurrence after his last surgery.

CONCLUSION

Surgical resection of both the primary tumor and pulmonary metastases remains the mainstay of treatment of primary leiomyosarcomas.

CHEST PAIN DUE TO A GIANT THYMOMA IN AN ADOLESCENT BOY

Chest pain in children is a common referral for emergency examination, although it is believed that the underlying condition is not a serious event. The authors present the case of a 17 years old male with complaints of chest pain with a very recent onset, constant, experienced after physical effort. All medical history and physical examination findings were normal, the poster-anterior chest X-ray revealed a heterogenous opacity in the middle third of the right hemithorax confirmed on computerized tomography as a large solid anterior mediastinal mass with a diameter of 7.5/10.3 cm. By thorax surgery the mass was identified in the anterior and superior mediastinum and total resection was achieved for the tumor mass and thymus. Pathology examination showed poor small and medium epithelial cells proliferation and the tumor was classified as thymoma type 1B. Mediastinum is a rare location of space occupying processes in children. Also, there is a high rate of asymptomatic lesions in this area, considering that half of them are incidentally discovered for various chest X ray examinations. Many causes of chest pain in children are benign; nonetheless, some serious events do exist sometimes and pediatricians must pay attention to identify and manage those cases.

Unusual presentation of mediastinal neurogenic tumours

Mediastinal neurogenic tumours generally arise as single benign lesions and their typical location is the costovertebral sulcus. In about 10% of cases mediastinal neurogenic tumours may extend to the spinal canal; occasionally they may extend to the cervical region and, more rarely, may be multiple or associated with other synchronous mediastinal lesions. The treatment of choice is surgical resection. This report describes three cases of unusual presentation of mediastinal benign schwannomas successfully treated at our Hospital. In the first case multiple simultaneous paravertebral lesions were resected through a posterior approach. In the second case a tumour of the posterior mediastinum extending to the cervical region was excised through a one-stage combined supraclavicular incision followed by left mini-invasive video-assisted thoracoscopic surgical techniques. The third case describes a patient with a posterior neurogenic mediastinal tumour with a synchronous parathyroid adenoma of the anterior mediastinum, which were both successfully resected by video-assisted thoracoscopic surgery.

[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).

Multilocular thymic cyst with epithelioid granulomata of unknown etiology: a radiologic and histopathologic correlation

Thymic cysts (congenital or acquired) are believed to account for 3% to 5% of all mediastinal masses. Multilocular thymic cysts are an acquired reactive inflammatory process arising within the thymus gland and are less common than the congenital unilocular type. Multilocular cysts have been reported in association with a variety of neoplastic, autoimmune, and infectious conditions. We report a case of a 23-year-old white man who presented with a 2-week history of progressive right-sided shoulder and chest pain. He was found to have an anterior mediastinal mass involving the thymus. This case of multilocular thymic cyst is particularly unique due to the presence of abundant epithelioid granulomata within the cyst, a finding that has not previously been emphasized as a histologic feature of these lesions, and one that expands the histopathologic differential diagnosis, warranting exclusion of infectious and autoimmune etiologies.

Minimally Invasive Thoracoscopic Resection of Paraspinal Neurogenic Tumors: Technical Case Report

Objective:

The posterior mediastinum is a common location for benign neurogenic tumors. They are frequently asymptomatic but can present with local compressive or neurological symptoms.

Methods:

Thoracoscopy is used increasingly over posterolateral thoracotomy for the removal of these lesions.

Results:

Complete resection of these tumors through a thoracoscopic approach is possible in most cases, but dumbbell tumors present as special challenges, which require a combined thoracoscopic and open posterior approach.

Conclusion:

In this article, we outline the technique of thoracoscopic resection of paraspinal neurogenic tumors through an operative video and a review of the literature to summarize the surgical outcomes of patients with these lesions.

Transesophageal mediastinoscopy by submucosal endoscopy with mucosal flap safety valve technique

BACKGROUND

Indications for NOTES (natural orifice transluminal endoscopic surgery) studied so far are limited to intra-abdominal surgery.

OBJECTIVES

To determine the technical feasibility and the safety of transesophageal mediastinocosopy by using the submucosal endoscopy with mucosal flap safety valve (SEMF) technique.

DESIGN

Two-week survival study with 4 porcine models.

INTERVENTIONS

High-pressure carbon dioxide injection and balloon dissection created a large submucosal working space for insertion of a cap-fitted endoscope. The muscularis propria was resected inside the submucosal space, and the mediastinoscopy was performed by using the endoscope inserted via the myotomy site. The muscular defect was sealed with the overlying mucosal flap, and the mucosal entry site was closed with clips.

MAIN OUTCOME MEASUREMENTS

Repeated endoscopy and necropsy were performed 2 weeks after the procedure.

RESULTS

With the SEMF technique, the posterior mediastinum was successfully accessed in all animals. Three pigs survived 2 weeks without clinical complications, and the defects were completely sealed by the mucosal flap. One pig with proximal esophageal mediastinal entry managed under voluntary respiration was euthanized because of pleural injury.

CONCLUSIONS

The SEMF technique provided safe entry into the mediastinum, with a protective submucosal tunnel that prevented mediastinal soiling. Mid to distal esophageal access is safer than the higher level access. Mechanical ventilation might allow safer respiratory support.

Endoscopic resection of thoracic paravertebral and dumbbell tumors

OBJECTIVE

Neurogenic paravertebral tumors are uncommon neoplasms arising from neurogenic elements within the thorax. These tumors may be dumbbell shaped, extending into the spinal canal or exclusively paraspinal. Generally encapsulated, they are located in the posterior mediastinum. In this report, we present our experience in the thoracoscopic resection of these tumors, including surgical technique and potential pitfalls.

METHODS

A retrospective review of patients undergoing endoscopic surgery for paravertebral tumors was undertaken. Patient demographics, charts, operative reports, and pre- and postoperative images were reviewed.

RESULTS

Between 1997 and 2004, 13 patients were treated thoracoscopically for paravertebral tumors in our departments. Our population consisted of four men and nine women. The median age was 44.9 years (range, 29-66 yr). Eight patients presented with pain, dyspnea, cough, and weakness. Five patients had tumors found incidentally. Sizes of the tumors varied from 3 to 9 cm. Final pathology included four neurofibromas, eight schwannomas, and one unclassified granular cell tumor. Gross total resection was achieved endoscopically in all cases. Three patients required a hemilaminectomy for resection of the intraspinal dumbbell component of the tumor during the same operation. The mean operative time was 229.5 minutes. The mean estimated blood loss was 371.1 ml. Postoperative morbidities included one each of tongue swelling, ulnar neuropathy, and intercostal hyperesthesia. The mean hospital stay was 2.8 days.

CONCLUSION

Paravertebral tumors in the posterior mediastinum are amenable to endoscopic removal, even in hard to reach locations. Tumors with intraspinal extension can be removed concurrently by performing a hemilaminectomy, followed by thoracoscopy, without the need for a thoracotomy.

Retroperitoneal Foregut Duplication Cyst Presenting as an Adrenal Mass

A 75 year-old woman presented to the authors’ institution with abdominal pain and early satiety. An adrenal mass was found on CT scanning. Laparoscopic adrenalectomy was performed, and the patient was found to have a retroperitoneal bronchogenic cyst adherent to the adrenal gland. The workup of an adrenal mass is discussed as well as the pathophysiology of bronchogenic cysts.

Tumors of the mediastinum

Tumors of the mediastinum represent a wide diversity of disease states. The location and composition of a mass is critical to narrowing the differential diagnosis. The most common causes of an anterior mediastinal mass include the following: thymoma; teratoma; thyroid disease; and lymphoma. Masses of the middle mediastinum are typically congenital cysts, including foregut and pericardial cysts, while those that arise in the posterior mediastinum are often neurogenic tumors. The clinical sequelae of mediastinal masses can range from being asymptomatic to producing symptoms of cough, chest pain, and dyspnea. This article will review the anatomy of the mediastinum as well as the different clinical, radiographic, and prognostic features, and therapeutic options of the most commonly encountered masses.

Prise en charge des kystes thymiques

OBJECTIVE

The thymic cysts are rare tumors of the neck and anterior mediastinum. The management of these patients in our institution is reported. Minimally invasive procedures are discussed.

PATIENTS AND METHODS

Six patients operated in our institution within ten years, with a follow-up of 7.1 +/-3.7 years are studied retrospectively.

RESULTS

There were four women and two men with an average of 39.8 +/-16.5 years. The tumor was found on chest radiograph in four asymptomatic patients, one took medical advice for laryngeal discomfort and another for dysphagia and dyspnea. The tumor was localized in the anterior mediastinum in three cases, in the cervicomediastinal site in two cases and in the cervical site in one case. CT scan was practiced in three patients with a mediastinal tumor and MR imaging in one of them. In patients with cervical or cervicomediastinal tumor, a cervical echography was practiced. All patients were operated on: three by cervicotomy, one by sternotomy, one by partial upper mini-sternotomy and one by right lateral video-assisted mini-thoracotomy. Histology confirmed benign epithelial thymic cyst.

CONCLUSION

There is no specific marker of thymic cysts. Only the surgical management, leads to precise the diagnosis and to treat these tumors. No mortality, no complications or recurrences are reported. The minimally invasive surgery takes an interesting place for thoracic location, to explore and treat these benign mediastinal lesions.

Thoracoscopy: the preferred approach for the resection of selected posterior mediastinal tumors

The posterior mediastinum is a common site for neurogenic tumors. These are mostly asymptomatic and detected incidentally during radiologic investigations. However, they occasionally present with compressive or neurologic symptoms. The tumors are mostly benign but can also be malignant. Left untreated, they continue to grow. Therefore, once detected, resection is always advised. Traditionally, resection has been performed by standard posterolateral thoracotomy. More recently, such tumors have been removed thoracoscopically. We report our experience with three such cases and present a comprehensive analysis of cases of thoracoscopic resection of posterior mediastinal neurogenic tumors reported in the English literature to suggest guidelines for their current management.

Primary mediastinal malignancies in children: report of 22 patients and comparison to 197 adults

PURPOSE

Examine a contemporary series of patients with primary pediatric malignant mediastinal tumors and determine epidemiology, histology, treatment, and survival. Patients and Methods. All malignancies diagnosed between January 1, 1973 and December 31, 1995 were analyzed.

RESULTS

Twenty-two patients, age 18 years or less, with pediatric primary mediastinal malignancies were identified from a database of 110,284 patients with primary malignancies. During the same period, 197 adult patients with primary mediastinal malignancies were identified. Fifty-nine percent of the pediatric patients were male. Median age was 11 years. Lymphoma was present in 55%, neurogenic malignancies in 23%, malignant germ cell tumors in 18%, and sarcoma in 5%. Neurogenic tumors presented in infants and lymphomas and germ cell tumors presented in teens (p = 0.005). In treated children, surgery was used more often in neurogenic tumors and germ cell tumors than in lymphomas (p = 0.002). Five-year survival was 74% for lymphomas, 67% for neurogenic tumors, 25% for germ cell tumors, and 61% overall (p = 0.23). Compared to adults, children had more neurogenic tumors (p < 0.001) and fewer thymomas (p = 0.0499). There were no significant differences in staging or survival between children and adults.

CONCLUSIONS

Pediatric mediastinal malignancies occurred with a frequency of 1/5,013 patients with malignant tumors. Lymphoma, neurogenic tumors, and germ cell tumors predominated. Compared to adults, children had more neurogenic tumors and fewer thymomas. Within the pediatric group, differences were found in age of presentation between histologic groups. These differences between adults and children, and between infants and teens, should be considered when evaluating a patient suspected of having mediastinal malignancy.

Primary sarcomas of the mediastinum: results of therapy

Primary sarcomas of the mediastinum are rare, and data concerning treatment and results of therapy are sparse.

OBJECTIVE

To assess presentation, management, prognostic factors, and survival in mediastinal sarcomas.

METHODS

We reviewed our experience with 47 patients with the diagnosis of primary sarcoma of the mediastinum. Data were collected from a computerized institutional database and medical records. Survival was analyzed by Kaplan-Meier method and comparisons of survival by log rank test.

RESULTS

The median age of 47 patients with mediastinal sarcoma was 39 years (range 2.5 to 69 years), with a male/female ratio of 1.6. The most common complaints were chest/shoulder pain (38%) and dyspnea (23%). The most common tumor types were malignant peripheral nerve tumor (26%), spindle cell sarcoma (15%), leiomyosarcoma (9%), and liposarcoma (9%). Operation was the primary treatment modality in 72% of cases (n = 34); 22 sarcomas (47%) were completely resected. The overall 5-year survival was 32%. High-grade lesions had a significantly decreased survival (5-year survival = 27%) compared with low-grade tumors (5-year survival = 66%) (p = 0.05). The overwhelming factor determining survival was the ability to completely resect the tumors (5-year survival 49% for complete resection; 3-year survival 18% for incomplete or no resection) (p = 0.0016). Despite complete resection, local recurrence occurred in 64% of cases.

CONCLUSION

Because the overall survival for patients with mediastinal sarcomas is 32% and the local recurrence is 64% for tumors completely resected, aggressive adjuvant therapy should continue to be systematically explored.

Lymphomas of the mediastinum

The purpose of this clinicopathologic overview is to describe the types of lymphomas that present in the mediastinum. A comparison of the frequency of the different subtypes of lymphoma that are found in children and adults is provided. In general, immunohistochemistry and immunophenotyping studies are essential to the laboratory workup of neoplasms presenting in the mediastinum. An assessment of proliferative index in lymphoma is most helpful to determine tumor aggressiveness and patient prognosis. Electron microscopy is most helpful in the differential diagnosis of mediastinal neoplasms, where lymphomas may be distinguished from nonlymphomatous neoplasms using key ultrastructural features. The role of electron microscopy in the subclassification of lymphomas is mostly academic, with a few exceptions. The varied ultrastructural appearance of Hodgkin's cells and of different subtypes of non-Hodgkin's lymphoma is illustrated, using cases from our patient files. An ultrastructural study of lacunar cells in Hodgkin's disease provides evidence that the formation of lacunae may have a structural and/or physiologic basis. Mummified cells showing some of the features of a physiologic form of cell death, called apoptosis, are also described.

Standard biplane roentgenography is highly sensitive in documenting mediastinal masses

The records of 30 patients with mediastinal masses were reviewed to evaluate the signs, symptoms, and preoperative tests that were most useful in diagnosing and localizing the masses. Sixteen (53%) of the tumors were benign, and 14 (47%) were malignant. Twenty patients were seen with symptoms. The most common symptoms suggesting malignancy were pain, weight loss, fever, and cough. Four of the 5 patients who were truly asymptomatic had benign lesions. All 4 patients with palpable adenopathy had malignant tumors. Posteroanterior and lateral chest roentgenograms detected the mediastinal mass in 29 (97%) of the 30 patients. All patients were operated on for tissue diagnosis or resection (13, median sternotomy; 8, right thoracotomy; 3, left thoracotomy; 2, low anterior cervical approach). Eight patients underwent mediastinoscopy, which was diagnostic in 6 and obviated the need for operation in 4. It was of particular value for patients with lymphoma, who can be managed without resection.

Thymic hyperplasia. I. True thymic hyperplasia. Review of the literature

The condition of true thymic hyperplasia is defined as an increase of both size and weight of the gland while it maintains normal microscopic architecture. It occurs in three different clinicopathologic forms: True thymic hyperplasia without any other disease is extremely rare and only seven well documented examples could be found in a review of the literature. Enlargement of the thymus gland is reported as a form of rebound phenomenon in a number of conditions like recovery from severe stress situations, after administration of steroids, and after treatment of malignant tumors. Finally, thymic hyperplasia has been described in association with endocrine abnormalities, sarcoidosis, and Beckwith-Wiedeman syndrome.

Fine-needle aspiration biopsy of the mediastinum

Fine-needle aspiration is a useful technique to identify neoplasms of many sites, such as breast, thyroid, and lung. Thirty-two mediastinum aspirates from 29 patients were reviewed. Five aspirates yielded insufficient material. Five aspirates were of benign lesions. Four aspirates were suggestive of but not diagnostic of malignancy. Eighteen aspirates contained malignant cells; in 13 of these, a definite cell type was identified, which usually was metastatic lung carcinoma; in five instances, the cell type could not be unequivocally identified. Complications were minimal, two instances of pneumothorax (6.3 percent) and two of hemoptysis (6.3 percent). No deaths or hemorrhage occurred. In 16 of the 29 patients (55 percent), thoracotomy was avoided because of fine-needle aspiration biopsy. It is concluded that fine-needle aspiration biopsy of the mediastinum is a safe, useful diagnostic tool. This procedure may obviate the need for thoracotomy in persons with inoperable cancer, thus lowering medical costs and length of hospital stay.

Mediastinal neurogenic tumours. Early and late results of surgical treatment

Early and late results of surgery for neurogenic mediastinal tumour were evaluated in 66 cases with a mean follow-up of 12 years. The series comprised 48 neurilemmomas, 8 neurofibromas, 7 ganglioneuromas, and neurinoma, neurofibrosarcoma and ganglioneuroblastoma each in one case. There were two early deaths (3%), one due to peroperative bleeding from the left subclavian artery and the other to acute myocardial infarction. Operative complications arose in 12 cases (18%), the most common being wound infection (3 cases). There were 17 late deaths (26.6%). In the neurilemmoma group, 3 of the 13 late deaths were related to the tumour or its treatment, and both deaths in the neurofibroma group were related to malignant transformation. Recurrence of tumour appeared in 3 of the 48 patients with neurilemmoma and also in the single patient with neurinoma as tumour classification. One neurilemmoma was a dumb-bell tumour, and operation in this case resulted in paraplegia. Malignant transformation appeared in 2 of the 8 neurofibromas 5 and 13 years postoperatively. Because of the risks of malignant degeneration and of recurrence, patients operated on for neurogenic mediastinal tumour should be carefully followed up for many years.

Primary angiosarcoma of the mediastinum: light and electron microscopic demonstration of Factor VIII-related antigen in neoplastic cells

An angiosarcoma developed in the superior mediastinum of a 50-year-old white woman. The ultrastructural appearance and the significance of Factor VIII-related antigen within the neoplastic cells are discussed.

Benign tumours of the oesophagus and oesophageal cysts

Eighteen patients with benign tumour or cyst of the oesophagus were operated on over a 26-year period at the Department of Thoracic and Cardiovascular Surgery of Uppsala University Hospital. The series comprised 11 cysts and 7 benign tumours, including one case of the rare myoblastoma. The incidence of operations was 0.33 per million population. There was no operative mortality and no subsequent morbidity from the oesophageal disease. The follow-up is complete. A review of the literature confirms that these lesions are rare and that they usually are submucosal. Many are asymptomatic (in our series only about 1/3 caused symptoms). The most common symptoms are those resulting from compression of the oesophagus, which can lead to obstruction and pulmonary complications. It may therefore be warrantable to operate on benign oesophageal tumours and cysts even in the absence of symptoms, thereby also confirming the diagnosis.

Thoracic neoplasms: imaging requirements for diagnosis and staging

This article reviews the pathophysiology of thoracic neoplasms and discusses current imaging recommendations for diagnosis and staging of these tumors. Particular emphasis is given to primary lung cancers, which comprise a variety of tumors of differing histologic type and behavior. The development of cost-effective diagnostic/staging sequences with continually changing imaging technology continues to be a challenging goal. Our recommendations are based on the TNM system and data from the current literature employing the experience from our institution.