Objectives: Superficially spreading early gastric cancer is characterized by wide horizontal extension without deep vertical invasion. This study aimed to clarify the clinicopathological characteristics and prognosis of this rare disease.
Methods: We defined superficially spreading early gastric cancer as any tumor invading the submucosal layer that measured > or =60 mm in diameter. The clinicopathological characteristics and results of surgery were compared between 60 patients with superficially spreading tumors and 621 patients with the common type (<60 mm in diameter).
Results: For superficially spreading cancers,significantly higher numbers of female patients, undifferentiated and scirrhous types, infiltrating growth and lymph node metastases were seen. The number of metastatic lymph nodes was greater than in the common type. There was no significant difference in the distribution of metastatic lymph nodes between the two groups. For superficially spreading tumors, wide gastrectomy with extended lymph node dissection was frequently employed. Lymph node metastasis, but not tumor diameter, was a prognostic factor in uni- and multivariate analyses.
Conclusions: Although superficially spreading early gastric cancer has histologically distinct properties, gastrectomy with lymph node dissection with sufficient surgical margin could be a suitable treatment.