1. Sung MS, Han SY, Choi SR, Shin WW. Four cases of double primary cancer. Korean J Gastrointest Endosc. 1993. 13:69–74.
3. Min JY, Lee HJ, Son HS, Kim JS, Kim HK, Cho YS, et al. A case of double primary cancer in the esophagus. Korean J Gastrointest Endosc. 2009. 38:24–27.
4. Lee JY, Lim HJ, Park MI, Park SJ, Chang HK, Lee KD. A case of carcinoma of the thyroid and cervical esophagus following irradiation. Korean J Gastroenterol. 2005. 46:129–132.
5. Kim SH, Lee SS, Kim JK, Oh PS, Yeo HS, Park HB, et al. Two cases of primary multiple cancer associated with esophageal cancer. Korean J Intern Med. 1991. 41:289–296.
6. Choi SH, Seong YR, Lee TY, Park JS, Jeong MH. A case of synchronous multiple primary cancers in esophagus and stomach with mutiple gastric cancers. Korean J Gastrointest Endosc. 1998. 18:71–75.
7. Yoon HJ, Baek HJ, Lee SM, Lee CK, Seo HR, Kim DH, et al. Three cases of multiple primary cancer in esophagus and stomach. Korean J Gastrointest Endosc. 1996. 16:459–467.
8. Billroth T. The general surgical pathology and therapeutics. 1889. Berlin: G Reimer.
9. Moertel CG. Multiple primary malignant neoplasms: historical perspectives. Cancer. 1977. 40:4 Suppl. 1786–1792.
10. Koo DJ, Yoon DS, Lee JJ, Park CJ. Clinical analysis of 65 multiple primary cancer cases. J Korean Surg Soc. 1999. 56:137–142.
11. Son HS, Kim JS, Cho YS, Kim HK, Min JY, Baeg MK, et al. Three cases of double primary cancer in the esophagus and stomach. Korean J Gastrointest Endosc. 2009. 38:28–33.
12. Hur YH, Ryu SY, Kim DY, Kim YJ, Kim SK. Study of combined multiple primary cancer in gastric cancer patients. J Korean Surg Soc. 2003. 64:296–301.
13. Ikeda Y, Saku M, Kawanaka H, Nonaka M, Yoshida K. Features of second primary cancer in patients with gastric cancer. Oncology. 2003. 65:113–117.
14. Dinis-Ribeiro M, Lomba-Viana H, Silva R, Moreira-Dias L, Lomba-Viana R. Associated primary tumors in patients with gastric cancer. J Clin Gastroenterol. 2002. 34:533–535.