Mesenchymal tumors of the mediastinum.III. Tumors of lymph vascular origin

Pulmonary Lymphangioleiomyomatosis: A Case Report in Postmenopausal Woman Treated with Pleurodesis and Progesterone (Medroxyprogesterone Acetate)

The main problem in the treatment of pulmonary lymphangioleiomyomatosis, which frequently occurs in the reproductive age, is the control of chylothorax and disease progression. We herein report a case of a 62-year-old woman who underwent surgery for recurrent chylothorax. Histologic examination of lung and lymph node biopsies demonstrated lymphangioleiomyomatosis. Thirty-six months after tetracycline pleurodesis and high-dose medroxyprogesterone acetate therapy, the disease was stable and chylothorax effectively controlled. It would therefore appear that hormonal treatment with medroxyprogesterone acetate may be beneficial in postmenopausal women.

Mesenchymal tumours of the mediastinum--part I

The mediastinum is an anatomically defined space in which organs and major blood vessels reside with surrounding soft tissue elements. The thymus is an important organ in the mediastinum, and many of the masses encountered in the mediastinum are related to this organ. Most neoplasms diagnosed in the mediastinum are epithelial tumours (thymomas and thymic carcinomas), lymphomas or germ cell tumours. In contrast, soft tissue tumours of the mediastinum are rare. In 1963, Pachter and Lattes systematically reviewed soft tissue pathology of the mediastinum, covering the hitherto described [2, 226, 227] In this review, based on the 2013 WHO classification of soft tissue tumours and the 2015 WHO classification of tumours of the lung, pleura, thymus and heart, we provide an updated overview of mesenchymal tumours that may be encountered in the mediastinum.

Cystic hygroma

Surgical management of cystic hygroma is very challenging since it has a thin wall consisting of endothelium which can easily be torn during its enucleation leading to recurrence. The other treatment options are intralesional injection of OK-432, triamcinolone followed by surgical excision, if necessary, injection of sclerosing agents, repeated aspiration, radiotherapy and finally spontaneous regression without any form of treatment. This is a case report of cystic hygroma of parotid region where regression occurred without any form of treatment.

Chylothorax in lymphangioleiomyomatosis

STUDY OBJECTIVE

Pulmonary lymphangioleiomyomatosis (LAM) is a rare, serious disorder characterized by proliferation of abnormal smooth-muscle cells and affects almost exclusively women of childbearing age. Optimal management of chylothorax, a well-recognized complication of LAM, in these patients has not been defined. This study was performed to characterize the clinical course and identify appropriate management options for chylothorax occurring in patients with LAM.

DESIGN

Identification and retrospective review of available medical records on patients with LAM and chylothorax.

SETTING

Tertiary-referral medical center.

PATIENTS

All patients with LAM seen at Mayo Clinic, Rochester, MN, from January 1, 1976, to December 31, 2000.

INTERVENTION

None.

MEASUREMENT AND RESULTS

Eight of 79 patients (10.1%) with LAM had chylothorax. All were women aged 33 to 51 years, and four patients had underlying tuberous sclerosis complex. These eight women represented 3.5% of the 229 patients with chylothorax seen over this 25-year period at Mayo Clinic Rochester. Six patients had unilateral pleural effusion and two patients had bilateral effusions at initial presentation. The size of the chylothorax varied and was not necessarily progressive. Management of chylothorax ranged from thoracentesis only to thoracotomy with thoracic duct ligation and parietal pleurectomy. When needed, pleurodesis by instillation of sclerosing agents or parietal pleurectomy appeared to be effective in controlling chylothorax.

CONCLUSIONS

Chylothorax occurring in patients with LAM has a variable clinical course. Although pleurodesis with or without thoracic duct ligation appears to be effective in controlling intractable chylothorax, less invasive treatments such as thoracentesis or observation may suffice in some cases. Management of chylothorax in patients with LAM should be individualized depending on the size and clinical effects of the chylous pleural effusion, as well as comorbid factors and local expertise.

Benign cranial mediastinal lesions in three cats

Cranial mediastinal lesions were detected in three cats, associated with respiratory impairment (case one), spontaneous pneumothorax (case two) and myasthenia gravis (case three), respectively. On gross and histological examination, the first case was considered either a lymphangioma or a branchial cystic mass of the thymic region of the mediastinum; a cystic lesion was suggested by sonographic detection of multiple anechoic cavitations within a circumscribed mass, while fine needle aspiration cytology excluded lymphosarcoma. The second case was diagnosed histologically as a cystic thymoma, but the third case was not examined microscopically. The masses were amenable to surgical excision in the first two cats, while this proved unnecessary in the third case because of resolution following treatment with dexamethasone. Corticosteroid responsiveness was unhelpful in distinguishing between these benign lesions and lymphosarcoma, as in two cases there was a partial or complete response to dosing with prednisolone or dexamethasone. These cases are presented to emphasise that conditions other than lymphosarcoma can produce cranial mediastinal lesions in cats, and that the prognosis for surgical treatment of lymphangiomas, multilocular thymic cysts and cystic thymomas can be excellent.

Lymphangioma of the middle mediastinum as an incidental finding on a chest radiograph

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Lymphangiomyoma of the Thoracic Duct with Previously Undescribed Epithelial Tubules

A case of mediastinal lymphangiomyoma with tubules covered with epithelium is reported. The epithelium of these tubules is morphologically identical to that of the bronchi. It is the first time that epithelial, presumably pulmonary, elements have been described in an extrapulmonary lymphangiomyoma. It is concluded that the present case of a mediastinal lymphangiomyoma suggests a hamartomatous malformation. Whether this applies in general to lymphangiomyomatosis still remains a matter of discussion.

Cervico-mediastinal lymphangioma

Two cases of cervico-mediastinal lymphangioma ppesenting in adults are reported. In one the lesion originated in the mediastinum and only when advanced showed extension into the neck. The other was associated with a cervical cystic hygroma. Both wwer relieved by one-stage excision. Although they are benign, the tendency of these lesions is to become progressively larger, and to infiltrate between the vital structures in the neck and mediastinum. These features, and the importance of early surgery, are illustrated by the patients we now report.

Lymphangiomyomatosis: morphogenetic study and ultrastructural confirmation of the histogenesis of the lung lesion

A 34-year old woman underwent a surgical intervention as a result of a retroperitoneal tumor. This tumor was excised and the pathological diagnosis was lymphangiomyoma. Two months later she developed a spontaneous right pneumothorax with a chylous pleural effusion. Roentgenograms showed that the lungs had developed a honeycomb pattern. She was treated surgically and at the same time a biopsy was performed. Sixteen months later she deveoped a left pneumothorax which necessitated additional surgery, and a further biopsy was taken. She died of respiratory insufficiency 2 years after the clinical onset of the symptoms. The pathologic material was studied by both electron and light microscopy in serial sections. The electron-microscopic study proved the muscular nature of this condition. The light microscopic study of the serial sections showed that the lung lesion was due to the proliferation of the muscle cells associated with the lymphatics surrounding the acini.

The lungs in lymphangiomyomatosis and in tuberous sclerosis

Two cases of pulmonary lymphangiomyomatosis (PL) are described and 33 other cases from the literature are reviewed. These are compared with one case of tuberous sclerosis with pulmonary involvement (PTS) and 32 other cases from the literature. There are no differences in lung function between these two conditions, both of which show airways obstruction associated with diffuse radiological lung changes. There are, however, both clinical and radiological differences and also differences in the distribution of the lesions and the histological location of the excessive smooth muscle; these indicate that PL and PTS are probably different entities and not polar forms of one condition. Finally, the strictly female incidence of PL suggests a sex-linked disorder, and it is postulated that this may be related to congenital pulmonary lymphangiectases.