To Cuneo in his masterly thesis the profession is indebted for the excellent description of the lymphatic system of the stomach, which is well shown in the diagram taken from his work (p. 19). The lymphatics, as will be seen, drain into the glands along the lesser curvature as well as into those along the greater curvature, especially towards the pyloric end of the stomach and in the adjoining portion of the great omentum ; thence the lymph passes through the coeliac glands on its way to the thoracic duct, which transmits it to the general circulation by way of the left subclavian vein.
On reaching the heart the lymph passes through the pulmonary circulation, and infective particles may be arrested in the lungs, or if passing onwards into the greater circulation they may be disseminated as emboli and lodge in any part of the body, in this way even passing back to the abdominal viscera.
When the pylorus is affected, extension takes place rapidly along the lesser curvature ; the lymphatics and the adjoining glands becoming involved as far as the point where the coronary artery joins the stomach, at which place the lymph-channels pass from the lesser curvature. The reason of almost constant extension in this direction is that this is the chief course along which the lymph stream travels from the stomach.
In consequence of this early extension a mere excision of the pylorus alone for cancer is, as a rule, almost useless, since to get beyond the disease it is necessary to remove a considerable portion of the lesser curvature with its adherent lymph-vessels and glands.
The lymph-nodes on the greater curvature do not usually extend further to the left than a point near the middle.
The dome of the stomach is almost devoid of lymph-vessels, hence in extensive gastrectomy this part of the organ can frequently be safely left to form part of the future stomach.
Mr. J. F. Dobson, in his Arris and Gale Lectures, February, 1907, showed the presence of a gland on the left of the oesophagus, and said that there were usually one or two lymph-nodes in the gastro-splenic omentum.
Cuneo observed that pyloric growth frequently spares the duodenum, hence when a tumour extends well into it from the pylorus the chances are that it may be inflammatory swelling around an ulcer. This fact has on several occasions enabled me to rest satisfied with a gastro-enterostomy when otherwise I should have performed a partial gastrectomy. The rule is, however, not absolute, as I have seen both cancer and sarcoma extend through the pylorus into the duodenum.