1. Japanese Research Society for Gastric Cancer (1993) The general rules for the gastric cancer study, 12th edn. Kanehara Shuppan, Tokyo
2. Warren S, Gates O (1932) Multiple primary malignant tumors. A study of the literature and a statistical study. Am J Cancer 16:1358?1414
3. Nishidoi H, Okamoto A, Kimura O, Kawaguchi H, Miyano Y, Tamura H, Shimizu N, Kaibara N, Koga S, Kishimoto H (1981) Clinical report of 60 multiple primary malignant tumors cases (in Japanese). Gann no Rinsho (Jpn J Cancer Clin) 27:693?697
4. Anan T, Miyabe M, Tuji H (1980) Clinical report of 31 multiple primary malignant tumors in our department (in Japanese). Geka Shinryo 6:697?701
5. Kasumi F, Togo S, Ota T, Takagi K, Kato H (1977) Study of cases with double carcinoma of the stomach and pancreas (in Japanese). Gan no Rinsho (Jpn J Cancer Clin) 23:1306?1314