Relationships between gastric development and anatomic bases of radical surgery for cancer.

The aim of this study was to determine with all possible accuracy the processes of embryologic development of the stomach and its lymphatics in order to confirm their supposed link with the modern anatomic bases of gastric cancer surgery. The knowledge of the anatomic behavior of the peritoneal folds and of the lymphatic drainage of the stomach is, in fact, considered the essential basis for the comprehension of the oncologic dissection of the stomach. The study was based on reconstruction of serial histologic sections of 9 human embryos and 8 human fetuses regarding the mesogastric area, as well as anatomic microdissection of 2 9-month fetuses. The proximal part of the stomach is not involved in the rotation mechanism of the other portions; the lesser sac development follows cranial migration of the spleen; the cardiac (pars cardiaca gastris) area is in continuity with the zone of paraaortic lymph node development; lateral and posterior lymph nodes of the hepatoduodenal ligament do not take origin in the dorsal mesogastrium: they develop together with the common bile duct and the ventral pancreas inside the mesoduodenum; the fusion of the dorsal mesogastrium and the gastric fundus with the posterior abdominal wall appears late in development. The embryologic study of the mesogastric area clarifies the real mechanism of development of the stomach and its lymphatic pathways with some differences from classic reports; these results agree with the more recent modification of the lymph nodes classification used in the radical treatment of gastric cancer.