Gastric remnant cancer as a metachronous multiple lesion.

The pathological characteristics and natural history of 35 gastric remnant cancers after partial gastrectomy for a malignant condition and 16 gastric cancers after gastrectomy for benign conditions were compared. Gastric remnant cancer following malignant disease was characterized by a well defined rather than diffuse appearance (in 43 versus 12 per cent of gastric remnant cancers after benign conditions, P < 0.05), location away from the anastomosis (83 versus 25 per cent, P < 0.05) and a shorter interval after the first operation (5-14 versus > or = 20 years, P < 0.01). The 15- and 16-year survival rates appeared to be worse for gastric remnant cancer after malignant than after benign disease, but there was no statistically significant difference between the two groups in a generalized Wilcoxon test. In the former, direct invasion to adjacent organs was frequently observed. These findings suggest that gastric remnant cancer after gastrectomy for malignancy may be a metachronous multiple lesion, while that following benign disease may occur as a new cancer caused by the partial gastrectomy. To improve the survival of patients with cancer after gastrectomy for malignancy, a rational extended operation may be useful.