Leuchaemia with a palpable enlargement of the spleen is very rare in carcinoma of the stomach, but when it exists the absolute exclusion of leucocythaemia is practically impossible. In most of the cases, however, the malignant disease shows itself by the development of a gastric tumour and dilatation of the stomach, or by the presence of gastric symptoms associated with a failure in the secretion of hydrochloric acid.

The Ascitic Form

In this variety the early development of ascites, with the frequent absence of gastric symptoms, renders the disease liable to be mistaken for tubercular peritonitis or cirrhosis of the liver.

Carcinoma of the peritoneum may occur either in the form of numerous discrete growths of considerable size or as a miliary affection of the serous membrane. In the former case examination of the abdomen reveals the existence of several tumours, whose tenderness and rapidity of growth are suggestive of their malignant nature, while in the latter no tumour can be detected either by palpation or digital exploration of the rectum. In both instances the effusion may be unaccompanied by pain or vomiting for two or three months, and the principal symptoms consist of distension after meals with excessive flatulence. Careful examination, however, will usually show that the constitutional symptoms are more pronounced than in other forms of ascites. The soft parts undergo rapid wasting, the lips and conjunctivae are markedly anaemic, and although the temperature is subnormal, the patient usually expresses an aversion to food. The skin is loose and dry, the secretion of urine is diminished, and oedema of the legs and thrombosis of the saphenous or femoral veins frequently occur. After a variable interval attacks of abdominal pain are apt to supervene and to prove severe, while in most cases nausea, vomiting, and haematemesis are observed. The physical signs vary according to the size of the peritoneal growths. When these are comparatively few in number, and principally affect the great omentum or the more superficial portions of the serous membrane, one or more discrete tumours may be detected on palpation, which rapidly increase in size, are tender on pressure, dull on percussion, and, though movable with respiration, gradually become fixed by adhesions to the neighbouring coils of bowel. Digital exploration of the pelvis will also detect one or more nodular growths in the pouch of Douglas or in the wall of the vagina or bowel, which are apt to press upon the bladder and to cause frequent and difficult micturition. Subsequently small metastases develop in the neighbourhood of the umbilicus, or infiltration of the linea alba occurs. In miliary carcinoma of the peritoneum the growths are too small to form palpable tumours, and the most important indications of the disease arise from the contraction of the mesentery and transverse mesocolon with which it is usually accompanied. In such the percussion-note over the front of the abdomen is uniformly dull instead of being resonant, while posteriorly the note over the lumbar region is much clearer on one side than on the other, owing to the adhesion of the mass of retracted intestine to the back of the abdominal cavity.

Examination of the fluid withdrawn by a syringe will often materially aid the diagnosis. In simple ascites the quantity of albumin is usually less than 2 1/2 per cent., while in cancerous peritonitis it amounts to 3-4 per cent., and is often as high as 5-6 per cent. When the growths are soft and numerous the fluid is often stained with blood, while in certain cases obstruction of the thoracic duct or lacteals gives rise to chylous ascites. When the sediment is examined by the microscope, groups of cancer cells may sometimes be detected, and even the existence of colloid carcinoma may be recognised by the characteristic changes in the cells. More frequently only a few epithelial cells are obtained by the use of the centrifuge, which exhibit budding or irregular forms of mitosis. Lastly, it is often observed that at the seat of puncture a small hard tumour develops from invasion of the subperitoneal tissue by carcinoma. Tubercular peritonitis in the adult is usually associated with fever. Pain is often a notable feature of the complaint in its early stages, and diarrhoea is apt to alternate with constipation. Loss of flesh and strength is less rapid than in carcinoma ; profuse perspirations occur at night, and rigors are not infrequent. The tumour is usually situated across the epigastrium, is nodular, comparatively dull on percussion, rarely very tender, and of slow growth. Tumours are rarely detected in the pouch of Douglas or in the tissues of the rectum or vagina, and in most instances signs of secondary inflammation of the pleura or lung manifest themselves after a few weeks. Ascites from cirrhosis of the liver is usually preceded by symptoms of chronic gastritis, and is accompanied by haemorrhoids. Abdominal pain is absent, there are no peritoneal tumours, and the floating intestines produce a resonant note on percussion over the umbilical region. The liver is found to be enlarged and hard, and a history of over-indulgence in alcohol can usually be obtained.

Table 34.-The Differential Diagnosis Of The Principal Diseases Accompanied By Early Ascites

The Dyspeptic Form

When a malignant growth of the stomach is merely accompanied by symptoms of indigestion, and for several months presents no indications of a tumour or of gastric dilatation, it is very apt to be confused with chronic gastritis or nervous dyspepsia.

Chronic gastritis may occur at any age and in either sex. In the great majority of cases there is a history of abuse of alcohol, or there are signs of disease in the lungs, heart, liver, or kidneys. Pain after food is rare, but the patient experiences fulness and discomfort during the period of digestion, accompanied by flatulence, acid eructations, and nausea. Vomiting may occur after meals, but it is also frequent in the early morning before breakfast, when an attack of retching causes the rejection of ropy mucus. The appetite is diminished but not lost, there is much thirst, and the tongue is usually large, pale, furred, and indented by the teeth. Constipation is apt to alternate with diarrhoea, and the urine is loaded with urates.