Primary mediastinal tumors

An overview of primary mediastinal tumors (primary mediastinal tumor) is not uncommon. According to the Shanghai Chest Hospital reported 1,228 cases of mediastinal tumors, the most common thymoma, followed by neurogenic tumors and teratoma : Other cyst, intrathoracic thyroid, bronchogenic cyst relatively rare. Most of these tumors are benign, but may be malignant. Clinical manifestations of thoracic mediastinal located in the Central. Since the entrance on the chest, eyes to the diaphragm, to about mediastinal pleura, around the sternum and thoracic spine to the sector. Kok sternum above the regional level as mediastinoscopy. Pericardial formerly known as anterior mediastinal and pericardial lie Department called the mediastinum, between the spine known as pericardial posterior mediastinum (Figure 1). Mediastinal tumors commonly have their predilection sites (Figure 2), which is the clinical diagnosis of reference. Figure 1 mediastinal division Figure 2 mediastinal tumors of the main sites (1) mediastinal tumor is the most common thymoma and intrathoracic thyroid tumor. 1. Thymoma more in the former, or mediastinal former mediastinum, the primary mediastinal tumors about 1 / 4 - 1 / 5, equal incidence between men and women. 30% of malignant, benign 30% and 40% of the potential or low-grade. Benign frequently asymptomatic, dual X-ray examination found. If the tumors are smaller in size and density faster, keep tabs on the sternum, hard X-ray examination found. Thymoma more adjacent ascending aorta, it could clear the conduction beat. According to the histological features can be divided into type lymphocytes, epithelial reticular cell, and epithelial cells, such as lymphocytes mixed. Common epithelial cells and lymphocytes positive for the quality of thymoma, if not complete surgical resection, recurrence and metastasis possible. Shanghai Zhongshan Hospital reported 12 cases of thymoma, surgery five cases have been significantly malignant, thymoma it can be considered to be low-grade malignant tumor that should be given to postoperative radiation therapy. Malignant thymoma easy violations surrounding tissue, can occur in varying degrees substernal pain and short breath, the terminally ill can produce vascular, The symptoms of nerve compression, as superior vena cava syndrome, diaphragm paralysis, such as voice hoarse. About 10% ~ 75% in patients with thymoma have the symptoms of myasthenia gravis. However, in patients with myasthenia gravis only 15% ~ 20% of the lesions are thymus. Removal of the tumor after about 2 / 3 of patients with myasthenia gravis symptoms improved. Minorities may occur in patients with aplastic anemia, Cushing syndrome, lupus erythematosus, γ - globulin deficiency and idiopathic granulomatous than myositis. X-ray examination, the former mediastinal seen on the round or oval pieces shadow, outline clearly benign smooth, coated integrity, and cystic degeneration often : Rough malignant irregular contours, can be accompanied by pleural reaction. Thymoma resection very good. Legg analysis of 51 cases of surgical treatment of thymoma, a local infiltration five-year survival rate of 23%. No infiltration in 5-year survival rate was 80%. Shanghai Chest Hospital reported 207 cases of thymoma after five-year survival rate of 59.7%, 10-year survival rate was 43.4%. 2. Intrathoracic goiter including congenital thyroid and vagal acquired substernal thyroid. The former rare. For the embryonic stage left in the mediastinum of the thyroid Zhu, developed into the thyroid tumor, located entirely within the chest, with no fixed location. The latter along the neck thyroid substernal submerged ago, mediastinum (Figure 3 A, B), the majority located in the front beside trachea, Minorities in the trachea rear intrathoracic goiter most benign, individual cases for adenocarcinoma. Mass traction or compression on the trachea, it will be irritating cough, short breath, and so on. These symptoms may be lying or suppression of the head and neck lateral shift aggravating. Pectoral or spinal compression, there will be chest tightness, back pain, even, there will be symptoms of hyperthyroidism. Experienced cough, hemoptysis, hoarseness, should take into account the possibility of malignant thyroid. About half of patients in the neck and surrounded nodular goiter. X-ray examination before it can be seen on video mediastinal block, was oval or spindle, contour clear, the majority preferred mediastinal side, also both sides of protruding. In the film, to see if the tumor calcification, with diagnostic value. Most cases of tracheal compression and displacement of a tumor and shadow with swallowing signs of moving up. Figure 3 A substernal thyroid tumor in the right upper mediastinum, the top wide, narrower bottom, Tracheal compression slightly (after anterior films) Figure 3B substernal thyroid cancer since thoracic inlet down, substernal extended forward (right-unit) (2) anterior mediastinal tumor growth anterior mediastinal tumor in the teratogenic tumor is more common. May, in any age, but 50% of cases the symptoms appeared in 20 ~ 40 years of age. Histologically Yun is the abnormal embryos or deformity. Teratoid tumor can be divided into two types : 1. Dermoid cyst is a cyst containing liquid, the capsule had originated from the tumor of the skin, hair, teeth. Often the single, double or more the the. Wall of fibrous tissue form, and the inner lining stratified squamous epithelium. 2. Teratogenic disease as a substantive mixed tumor. From the outside, and within three mesoderm tissue containing cartilage, muscle, bronchus, breast tissue, nerves and blood vessels, and so on. Malignant teratoma inclined than dermoid cyst, can often become sexual table carcinoma or adenocarcinoma. Reported 386 cases teratoma, which 14.2% were malignant. Shanghai Zhongshan Hospital 10 teratoma, 2 were malignant. Small size, often asymptomatic, many of the X-ray examination found. If pay increases tumor oppression adjacent organs, organ can produce symptoms of oppression, as the inferior vena cava pressure, can occur superior vena cava syndrome; recurrent laryngeal nerve compression, Health hoarseness; Tracheal compression can occur short breath, Patients sit at the gas intensified. Bronchial ulceration to the cyst can be expectorated with hair, sebaceous gluey fluid. Liquid plastic inhaled, can tip lipid and lipid pneumonia granuloma. Cyst a secondary infection may develop fever and carry loads of toxic symptoms. If the cyst in a short period of time is rapidly increasing, should think of malignant transformation, tumor secondary infection or bleeding may be. Suppurative cyst rupture into the chest or pericardium, can occur pericardial effusion or empyema. X-ray examination cyst located in the anterior mediastinum, heart aortic arch main junction, a few positions higher, close to the former, mediastinum, can be located in the former mediastinum. Mediastinal more to the side of abdomen, to be a minority on both sides bulging, will be enormous - convex posterior mediastinum, and even earned the side of the chest. Formed a round or oval-shaped, clear edge and more common wall calcification. Sometimes the characteristics of the shadow of teeth and bone (Figure 4). Figure 4 Teratoid tumors within bone, teeth and hair (3), mediastinal tumor most of the lymph node tumors. Common in Hodgkin's disease, reticular cell sarcoma, lymphoma, and so on. Most mediastinal lymphadenopathy were characterized, but also can invade the lung tissue infiltrates. Short course of the disease, symptoms progress rapidly, accompanied carry loads of enlarged lymph nodes, irregular fever, hepatosplenomegaly, and anemia. X-ray examinations showed enlarged lymph nodes located on both sides of tracheal and bilateral hilar. Obviously enlarged lymph nodes can be blended into a block, homogeneous density, it will be Oita leaves, but without calcification. Bronchial often soar narrowed. (4) mediastinal tumor almost all of neurogenic tumors. Can be found in the spinal cord, intercostal nerve ganglion and the vagus nerve, benign and malignant. Have benign schwannoma, neurofibroma and paraganglioma; A malignant schwannoma sarcoma and nerve fibers. Electron microscopic examination found schwannoma with Neurofibrosarcoma ultrastructure similar, but with different collagen. The great majority of neurogenic tumors in the posterior mediastinum Paraspinal groove (Figure 5 A, B), sometimes also in mediastinum, Most are capsule. X-ray signs of the smooth, round isolation mass. Huge mass forced intercostal space widened or intervertebral foramina increase. Sometimes the tumors showed dumbbell up under the intervertebral foramina, invasive cervical spine, spinal cord compression caused symptoms. Neurofibromatosis more common in young adults, usually asymptomatic. Tumors can produce greater compression symptoms, or if the scapula after back pain, short breath, and so on. Figure 5 A mediastinal schwannoma thoracic tumor in the right side, gourd-like was (before the after-film) Figure 5B schwannoma mediastinal tumor in the posterior mediastinum, overlap in the thoracic, gourd-like was (right-films) (5) bronchogenic cyst can occur in any part of the mediastinum, mostly located in the trachea, peribronchiolar or near bronchial LAI change. Bronchogenic cyst is a congenital more from the trachea crowds buds, more common in children under the age of 10. Usually asymptomatic, and if linked to bronchial or pleural, and fistula formation. Secondary infections are cough, hemoptysis, sputum, even empyema. X-ray examination in the upper mediastinum Central, trachea or bronchial nearby, showing a round or oval, homogeneous density, Massive clear border shadow was lobes or calcium leaves. If the cyst and bronchial similarities can be seen on planar.