Trend in gastric cancer:35 years of surgical experience in Japan

AIM:To investigate the trend in gastric cancer surgery in the context of rapid therapeutic advancement in Japan and East Asia.METHODS:A retrospective analysis was performed on 4163 patients who underwent gastric resection for gastric cancer with histological confirmation between 1971 and 2007 at the surgical unit in Kitasato University Hospital,to determine the trend in gastric cancer requiring surgery.RESULTS:Gastric cancer requiring surgical resection increased in our hospital,but the incidence adjusted for population was constant during the observed pe-riod.Interestingly,the ratio of diffuse type/intestinal type gastric cancer was unexpectedly unchanged,and that of advanced/early gastric cancer(EGC)was,however,markedly reduced,while the actual incidence of potentially curative advanced gastric cancer tended to decrease.The incidence of EGC requiring surgery tended to increase as a whole,which is consistent with increased prevalence of endoscopic surveillance.As a result,overall survival and mortality of gastric cancer requiring gastric resection has recently markedly improved.CONCLUSION:In Japan,planned interventions may improve surgical gastric cancer mortality,but an unexpected trend of persistent existence of intestinal type cancer suggests the need for more robust medical intervention.

Effects of Bare-Ground Revegetation Techniques Using Imperata cylindrica on Changes in the Plant Cover and Species Richness during Early Succession

Riverdikes are habitats that must be revegetated quickly in order to prevent soil erosion. With increasing pressure to improve the cost efficiency of management, new revegetation techniques suitable under reduced mowing frequencies are required. Imperata cylindrica (L.) P. Beauv. is an important component of grasslands in several Asian countries. Its vigorous rhizome elongation should be useful for quickly covering bare ground. We tested the effects of sowing (at two densities), transplanting, and sodding of I. cylindrica on plant cover and species richness of established vegetation over 3 years. The sodding and high-density sowing treatments achieved the most rapid increase in cover, followed by low-density sowing, transplanting, and the control. By year 2, however, the cover in the low- and high-density sowing treatments was similar. The sodding treatment had significantly fewer species than the other treatments in year 1. Between years 1 and 2 and years 2 and 3, the total number of species increased in the transplanting treatment, whereas it decreased in the sodding and two sowing treatments. Accordingly, if stabilization and erosion control are the priority, introduction of I. cylindrica using sod and high-density sowing is the most suitable method. If immediate green-up is not imperative, low-density sowing is likely to provide available resources for new seedlings of diverse species to become established, allowing the introduction of representative species in semi-natural grasslands. More research will be needed on the effects of introducing diverse species (e.g., sowing seed mixtures) that include I. cylindrica on the resulting floristic composition.