Among 402 patients with squamous cell carcinoma of the oesophagus, gastric wall involvement was evident in 32 (8.0 per cent). These could be grouped into four types according to the pattern of involvement: group 1 included six patients with gastric involvement via metastases in perigastric lymph nodes; group 2 consisted of 11 patients with gastric intramural metastasis; group 3 contained 12 with direct invasion of the gastric wall by the oesophageal squamous cell carcinoma; and group 4 three patients with intraepithelial spread of oesophageal cancer to the gastric epithelium. Prognosis was poor, all patients dying except for one in each of groups 3 and 4. The mean survival time was 5.6, 8.6, 14.8 and 18.7 months in groups 1, 2, 3 and 4, respectively. Gastric involvement via metastases to lymph nodes and by intramural metastasis therefore indicates an extremely poor prognosis, while the prognosis in groups 3 and 4 was influenced by the depth of invasion and lymph node metastasis of the oesophageal cancer. Histological examination of tissues from group 4 patients demonstrated that malignant squamous cells proliferated and invaded the gastric epithelial layer, that is, there was intraepithelial spread of the oesophageal cancer.