MEDIASTINAL GBOWTHS. 335 



glands may aid the diagnosis of both primary and secondary 

 mediastinal growths. The supraclavicular, the axillary, and 

 the inguinal glands are accessible, and the abdominal glands 

 cnn be palpated if enlarged to any great extent. The connection 

 of the supraclavicular and axillary glands with the lymphatics 

 of the mediastinum is not direct. The supraclavicular glands 

 receive no efferents from the mediastinal groups, but the ducts 

 of both groups open at the junction of the internal jugular and 

 subclavian veins. When the supraclavicular glands are invaded 

 in connection with malignant disease of the thorax it is probably 

 by retrograde infection. A small gland which lies deeply behind 

 the clavicular origin of the left sterno-mastoid muscle, and is 

 sometimes known as Virchow's gland, is usually the first gland 

 involved by malignant infection from below, whether from lung, 

 pleura, oesophagus, or stomach. It has also been pointed out 

 that growth may reach the posterior triangle by travelling along 

 the sheath of the subclavian artery. 



The axillary glands are in indirect communication with the 

 lymphatics of the parietal pleura. The efferents from the 

 parietal pleura pass into the intercostal lymphatic trunks, and 

 the latter, by means of trunks which accompany the perforating 

 branches of the intercostal arteries, communicate with the axillary 

 glands. The axillary glands are in turn continuous with the 

 infraclavicular or subclavian group. 



Lymphosarcomata, arising in the thoracic lymph glands, have 

 a tendency to creep along the mediastinal connective tissue 

 surrounding the air tubes and great vessels. They envelop the 

 trachea and bronchi, and so invade the lung from its root. 

 Descending in the sheaths of the pulmonary artery and aorta, 

 they invade the pericardium. Extending towards the heart 

 around the superior vena cava and the pulmonary veins, they 

 may actually invade the auricles. They may also invade the 

 myocardium by travelling along the sheaths of the coronary 

 arteries. They have a tendency to fungate into veins but not 

 into arteries, and masses of loose growth have been found in the 

 cavities of both sides of the heart. Passing upwards in the 



