Rational lymphadenectomy for early gastric cancer with submucosal invasion: a clinicopathological study.

Among all the patients who underwent gastrectomy for primary solitary gastric cancer at our department from 1979 to 1994, 228 patients had gastric cancer that invaded the submucosal layer. These cases were thus examined clinicopathologically, including the extent of submucosal invasion. No lymph node metastasis was found in any of the cancers measuring less than 2 cm in diameter. Macroscopic type I lesions or various combined types (IIa + IIc, IIc + IIa, IIc + III) were more likely to infiltrate deeply and were also associated with a high incidence (18%-25%) of lymph node metastasis. No lymph node metastasis or vascular invasion was found in any simple type IIa lesions. The incidence of lymph node metastasis was 3% in simple type IIc cancers measuring 3 cm or less. In addition, submucosal microinvasion (sm1) simple type IIc cancers showed no accompanying lymph node metastasis or vascular invasion. We thus conclude that a full-thickness partial resection of the stomach, such as a laparoscopic local resection, is applicable to cancers measuring 3 cm or less provided that they are either simple macroscopic type IIa or simple type IIc sm1 cancers.