Biological significance of localized Type IV scirrhous gastric cancer

The prognosis of type IV scirrhous gastric cancer (SGC) is extremely poor. Linitis plastica (LP), the so-called 'leather bottle stomach', is believed to be a typical case of SGC, which is usually diagnosed as a far-advanced gastric cancer. The pathogenesis of this disease remains unclear. Although typical SGC often invades the entire stomach, atypical cases show SGC localized to one region of the stomach. The aim of the present study was to investigate localized SGC (LSGC) and its biological significance. A total of 509 patients with advanced gastric cancer who underwent gastrectomy were evaluated. These patients were divided into three groups as follows: 19 patients with type IV scirrhous lesions invading the whole stomach (defined as LP), 60 patients with type IV scirrhous lesions localized in less than two thirds of the stomach (defined as LSGC) and the remaining 430 patients with all other types of gastric cancer (OGC), and then clinicopathologically compared. Results showed that LP had deeper invasion (p=0.006), more frequent peritoneal dissemination including positive cytology (p=0.01 and p=0.018) and lower curability (p=0.03) compared with LSGC, whereas LSGC showed a higher malignant potential in a number of clinicopathological factors compared with OGC. Univariate analysis showed that survival in patients with LP was significantly poorer than in those with LSGC (p=0.002) whose survival was, in turn, inferior to those with OGC. By contrast, LSGC was not a prognostic factor in SGC according to the multivariate analysis. The findings of this study suggested that the malignant status of LSGC differs from that of LP, and that curative gastrectomy is effective in improving the outcome for LSGC but not for LP, as LSGC may represent the prelinitis condition.