In the majority of cases the occurrence of intestinal obstruction is due to direct extension of the disease to the transverse colon ; but in three instances which have come under our notice the condition was dependent upon malignant stricture of the ileo-caecal valve, of the descending colon, or the rectum. In every instance the intestinal symptoms completely masked those arising from the primary complaint, which in two out of the three cases was not recognised during life. It is possible that in many instances of this description the intestinal lesion is really a primary growth, and not a mere secondary deposit (vide p. 24).
This occurs in about 13.7 per cent, of all cases, and is most common when the body of the stomach is affected or the pylorus infiltrated without the production of a stricture.
In four-fifths of the cases the icterus arises from secondary disease in the head of the pancreas, or from pressure upon the hepatic or common bile-duct owing to an extension of the growth behind the stomach. Metastases in the liver, portal thrombosis, and septicaemia are chiefly responsible for the remaining cases.
As a rule the icterus develops slowly, and the skin gradually acquires the greenish or black tinge indicative of a complete and permanent block of the bile duct. Occasionally, however, its onset is quite abrupt, and in rare instances it is the first symptom to attract attention (Michel). Temporary improvement sometimes ensues from the use of saline purgatives, or the colour of the skin and the urine varies in intensity from week to week. The liver is invariably enlarged, and somewhat tender upon pressure, and if ascites is present the fluid is usually bile-stained. The complication tends to shorten life by producing further impairment of the appetite and by increasing the rapidity of the emaciation. Occasionally death ensues rapidly from a form of coma like that met with in acute yellow atrophy of the liver.