TUMORS OF THE MEDIASTINUM
Tumors of the mediastinum include neurogenic tumors, tumors of the thymus, lymphomas, germ cell, cysts, and mesenchymal tumors. These tumors may be malignant or benign. These tu-mors are usually described in relation to location: anterior, mid-dle, or posterior masses or tumors.
Nearly all the symptoms of mediastinal tumors result from the pressure of the mass against important intrathoracic organs. Symp-toms may include cough, wheezing, dyspnea, anterior chest or neck pain, bulging of the chest wall, heart palpitations, angina, other circulatory disturbances, central cyanosis, superior vena caval syndrome (ie, swelling of the face, neck, and upper extremities), marked distention of the veins of the neck and the chest wall (evidence of the obstruction of large veins of the mediastinum by extravascular compression or intravascular invasion), and dyspha-gia and weight loss from pressure or invasion into the esophagus.
Chest x-rays are the major method used initially to diagnose me-diastinal tumors and cysts. CT scans are the gold standard for as-sessment of the mediastinum and surrounding structures. MRI may be used in some circumstances, as well as PET scans.
If the tumor is malignant and has infiltrated surrounding tissue, radiation therapy and/or chemotherapy are the therapeutic mo-dalities used when complete surgical removal (discussed below) is not feasible.
Many mediastinal tumors are benign and operable. The location of the tumor (anterior, middle, or posterior compartments) in the mediastinum dictates the type of incision. The common incision used is a median sternotomy; however, a thoracotomy may be used, depending on the location of the tumor. Additional ap-proaches may include a bilateral anterior thoracotomy (clamshell incision) or video-assisted thoracoscopic surgery. The care is the same as for any patient undergoing thoracic surgery. The major complications include hemorrhage, injury to the phrenic or recurrent laryngeal nerve, and infection.