Abstract
To determine whether the limited surgery is possible for the early gastric cancer invading submucosal layer (sm-cancer), a total of three hundred and seventy-eight cases with sm-cancer were investigated clinicopathologically. We divided sm-cancers into the following three subgroups according to the degree of cancerous invasion: sml group with minute submucosal invasion, sm2 group with invasion to the mid-submucosal layer, and sm3 group with deep and massive submucosal invasion near to the proper muscle. As a result, there was no lymph node metastasis in cases of sm-cancer less than 10 mm, in cases of the elevated type cancer less than 20 mm, or in cases of the differentiated sml or sm2-cancer less than 20 mm. However, the reports on the micro lymph node metastasis, which could not be detected in the conventional pathological examination, suggests that the evaluation of lymph node metastasis using conventional method is insufficient as an indicator for the plan of limited surgery. Consequently, to determine the strict indications of limited surgery, we examined lymphatic invasion of the cancerous lesion which related closely to lymph node metastasis. The examination of lymphatic invasion demonstrated that lymph node dissection can be omitted in cases of differentiated sml-cancer less than 10mm. However, the preoperative diagnosis of sml of less than 10 mm had been difficult. Thus, the lymphadenectomy should be performed for cases diagnosed as SM-cancer preoperatively at the present time.
