Carcinoma is almost always accompanied by some alteration in the shape of the stomach. In most cases this takes the form of an increase of size, but occasionally the viscus becomes greatly thickened and contracted, or presents some less regular deformity.
It is usually stated that disease of the pylorus is always accompanied by gastric dilatation, owing to the retention and decomposition of the food which ensue from obstruction of the orifice. This, however, is hardly accurate, since many cases of pyloric cancer are associated with contraction rather than dilatation of the stomach, while gastric enlargement may exist without any stenosis of the outlet. Thus, Lebert found that out of twenty cases in which the pylorus was obstructed the stomach was dilated in thirteen and contracted in seven; and out of nine instances where the orifices were free from disease the organ was dilated in four and contracted in five. Our own series includes ninety-eight cases of pyloric disease in which special mention is made of the size of the stomach after death ; of these the organ was described as ' much dilated ' in forty-one, ' dilated ' in eleven, ' normal' in ten, and ' contracted ' in thirty-six.
It is therefore obvious that the stomach varies considerably in size in different cases, even when affected by the same lesion, and that the factor which determines its ultimate condition may often be independent of the original disease.