NEOPLASMS IN HORSES EIVER. 



Sarcoma. This is usually a secondary formation from the 

 primary tumors in the spleen and peritoneum, and it occurs as 

 multiple masses throughout the substance of the gland. The 

 liver is greatly increased in size, extending far beyond the last 

 rib on the right side, and weighing when removed as high as 70 

 lbs. (Mason), or even 88 Bbs. (Cadeac), in extreme cases. 



The whole surface of the liver may show bulging, rounded 

 masses, and the morbid growth may have involved the capsule 

 and caused adhesion to the back of the diaphragm (Bachstadt). 

 The cut surface of the neoplasm is smooth, elastic, yellowish and 

 circular or oval in outline. It may have a variable consistency — 

 friable or tough, according to the activity of growth and the 

 relative abundance of cells and stroma. The portal glands are 

 hypertrophied and thrombosis of the portal vein is not uncommon. 



Microscopic examination of the dark red scrapings shows nu- 

 merous blood globules, intermixed with the round or spindle 

 shaped cells and nuclei of the tumor. Sections of the tumor 

 show these cells surrounded by a comparatively sparse fibrillated 

 stroma. The round cells may vary from .005 to .05 m.m. They 

 contain one or more rather large nuclei and a number of refran- 

 gent nucleoli. The nuclei are often set free by the bursting of 

 the cells in the scrapings. They become much more clearly de- 

 fined when treated with a weak solution of acetic acid. Small 

 grayish areas in the mass of the tumor represent the original 

 structure of the liver, the cells of which have become swollen and 

 fatty. 



A liquid effusion more or less deeply tinged with red is usually 

 found in the abdominal cavity. 



Symptoms are those of a wasting disease, with some icterus, 

 sometimes digestive disorder, and a marked enlargement of the 

 liver. The last feature can be easily diagnosed by palpation and 

 percussion. If an examination through the rectum detects the 

 enlargement and irregular rounded swellings of the surface of the 

 liver or spleen, or the existence of rounded tumors in the mesen- 

 tery or sub-lumbar region, this will be corroborative. The pre- 

 cise nature of the neoplasms can only be ascertained after death. 

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