Factors influencing the prognosis in gastric cancer treated by curative resection include lymph node metastasis and the extent of invasion of the gastric wall. Lymph node metastasis can be removed surgically, but the extent of invasion is not amenable to external measures. Of these two factors, the extent of wall invasion has the greatest influence on prognosis in cases undergoing curative resection. With lymph node removal of equal extent the prognosis worsens in proportion to the depth of invasion. Further, lymph node metastasis increases with increasing depth of invasion. Metastasis was seen in Group 2 and 3 nodes in more than 60% of cancer with invasion beyond the Tunica muscularis propria (pm), indicating that wide lymph node removal is essential in cancers with deep invasion of the wall. The effects of extended radical operation on the host as illustrated by the indices of total serum protein and albumin levels were no different from those of less extensive resections. It was confirmed that extensive radical resection did not delay postoperative recovery.