Although rare, gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. The asynchronous occurrence of other malignancies in patients with GIST during the clinical course is relatively common. However, the synchronous coexistence of GIST and lung cancer has only rarely been reported. We experienced a case of coincidental primary lung adenocarcinoma and intestinal GIST. The present case is not only of interest due to the rare coincidence of GIST and lung cancer, but also because there was an epidermal growth factor receptor gene mutation in the lung cancer and a c-kit mutation in the GIST.

A 54-year-old man was admitted to our hospital for further examination following a chest radiographic screening test. He was asymptomatic but had an elevated serum concentration of alpha-fetoprotein. Chest computed tomography (CT) and magnetic resonance imaging showed a posterior mediastinal mass in the left thoracic paravertebral region. CT-guided percutaneous needle biopsy was performed, and the histological findings confirmed nonseminomatous germ cell tumor (NSGCT). Gonadal examination and F-18 fluorodeoxyglucose positron emission tomography findings indicated the posterior mediastinum as the origin of the disease. Reports of primary NSGCT in the posterior mediastinum are extremely rare.

Most mantle cell lymphoma patients show remarkable disseminated disease at the initial diagnosis. We describe two cases of mantle cell lymphoma mainly involving thoracic lesions at the initial presentation of the disease. The clinical presentations were right hilar lymphadenopathy in one case and right pleural thickness in the other. The diagnosis of mantle cell lymphoma was confirmed by immunohistochemistry, including CD5, CD 20, and cyclin D1, and the presence of t(11 ; 14)(q13 ; q32) by fluorescence in situ hybridization. These thoracic manifestations at the initial diagnosis should be taken into consideration for the clinical spectrum of mantle cell lymphoma.

Although it is important to retain the flood water within the river channels by using dikes and reservoirs, these facilities alone cannot cope with excessive floods. In Japan, appropriate combination of facility-based and non-facility-based countermeasures is getting more important. To determine nonfacility-based countermeasures, we need to simulate flood hazardous situation. However, simulation models which include only evacuating on foot are not enough because our society and our lifestyles are based on using cars.In this study, we developed a model to express the behavior of the car in three simple modes. This enables us to simulate the car's actions in a realistic manner at least. The performances of this model have been tested in the several simulation results in actual flood-plain areas in Japan.

During the 2011 Great East Japan Earthquake, houses, roads and lifelines suffered serious damege due to liquefaction at many excavated and replaced grounds in eastern Hirai district of Kamisu City. Main reasons of the damage were: i) differential ground settlement occurred at the edges of the excavated zones, and ii) penetration of houses into the ground. Then appropriate countermeasures to mitigate the damage during future earthquakes were studied by analyses and in-situ tests. As a result, the method of lowering the water table was selected. The applicability of the method to this district was studied by in-situ drainage tests.