TUMOURS OF THE MEDIASTINUM. 369 



TUMOURS OF THE MEDIASTINUM. 



Sarcomata, carcinomata, lymphomata, and lympho-sarcomata all 

 occur in the mediastinum. They attack young healthy animals, and 

 sometimes develop with such rapidity that in a few weeks they become 

 generalised and invade the heart, lungs, and principal viscera. Their 

 cause is at yet unknown. 



Symptoms. At first sight the symptoms are much like those of 

 pericarditis caused by foreign bodies. They consist in deformity of 

 the presternal region, swelling of the jugulars, submaxillary oedema, 

 irregular pretracheal tumefaction, etc. 



The tumour, whatever its nature, commences in the mediastinmn, 

 develops towards the entrance to the chest, where it projects, and before 

 long produces in the pretracheal region clearly marked oedematous 

 swelling. 



Between the two first ribs the tumour compresses the carotids, the 

 jugulars, the nerve trunks, and also the trachea and oesophagus, pro- 

 ducing difficulty in the return circulation, especially in the jugulars, 

 swelling in the submaxillary space, loss of appetite and dyspnoea. 



Palpation aft'ords indication of a tumour of soft consistence, bosse- 

 lated, more or less adherent to the skin, usually painless on pressure, 

 and of irregular development. Compression of the oesophagus inter- 

 feres with the deglutition of rough forage, impedes rumination, prevents 

 eructation, and thus produces trifling but permanent tympanites. 



The heart is aflected reflexly or directly as a result of generalisation 

 of the tumour, and the pulse may rise to 70 or even 120 per minute. 



During the first stages neither auscultation nor percussion points to 

 any pulmonary lesion. At a later stage the lung itself may be affected. 

 The other important functions are normal. 



Animals suffering from sarcoma, carcinoma, or lympho-sarcoma of 

 the mediastinum waste very rapidly, lose appetite, become feverish, and 

 soon develop cachexia. 



Diagnosis. The diagnosis of tumour of the mediastinum is easy, 

 because of the well-marked character of the apparent symptoms. 



Prognosis. The prognosis must be regarded as extremely grave, 

 and in most cases fatal, for there is no active method of intervention, 

 extirpation being impossible. 



There is no treatment. The animal should at once be slaughtered. 



D.C. 



