Correspondence to: Dr. Takeshi Isobe, Department of Internal Medicine, Division of Clinical Oncology & Respiratory Medicine, Shimane University Faculty of Medicine, 89-1, Enya cho, Izumo, Shimane 693 8501, Japan (Tel: 81-853-20-2580. Fax: 81-853-20- 2580. Email: isobeti@med.shimane u.ac.jp)