Dorsal approach for advanced gastric cancer invading the transverse mesocolon

Minimally invasive gastrectomy is increasingly performed for advanced gastric cancer, but the indication for this procedure for a tumor invading adjacent structures is still limited. In cases with tumors invading the transverse mesocolon, a large tumor together with the involved mesocolon blocks the surgical view, which prevents evaluation of the extent of invasion and makes it difficult to ensure oncologically adequate resection. To solve these technical issues, we established a novel method that uses a dorsal approach. By approaching the transverse mesocolon from the dorsal side, tumor penetration and involvement of the colic vessels or pancreas can be evaluated, and margin-free resection of the tumor becomes easier. In a series of 13 patients with mesocolon invasion, a dorsal approach enabled minimally invasive margin-free resection in 11 cases by resection of the anterior layer of the mesocolon (n = 6); enucleation of the mesocolon (n = 4); or enucleation plus distal pancreato-splenectomy (n = 1). Two patients with broad invasion that obstructed the view underwent combined colectomy by open conversion. A major postoperative complication of pancreatic fistula following distal pancreatectomy occurred in one case. These results suggest that a dorsal approach may be useful for minimally invasive combined resection of gastric cancer invading the transverse mesocolon.