We report six cases of scirrhous carcinoma of the stomach in which we were able to observe the natural history of serial radiographs. All the patients developed scirrhous carcinoma of the stomach in an observation periods ranging from 2 to 15 months (mean: 5.8 months). No abnormalities or obvious findings indicative of a carcinoma were detectable, on the prior radiographs, even when they were reviewed. Endoscopy was also performed in two patients during the observation period, and no lesions were detected. At the time of diagnosis, two patients were inoperable because of metastases and died of the disease 2 and 5 months later. Three patients died of the disease 5, 8, and 26 months after gastrectomy, respectively. Only one patient is free of disease 16 months after gastrectomy. Our findings suggest that the difficulty of detection and the rapid growth of this tumor may explain why it is seldom detected at an early stage and has a very poor prognosis.