ABSTRACT
Multiple primary cancer is a state of disease that developed more than two cancers in an individual, independently. Multiple primary malignant cancer is divided to synchronous and metachronous type depending on the interval between their diagnoses. Synchronous multiple cancer is diagnosed within an interval of six months and metachronous multiple cancer more than six months interval. As further advance in diagnostic techniques and treatment method bring about progressive increase in the number of individuals living in the 'cancer age' group. So, the population of patients with subsequent primary cancer will increase and after all the incidence of multiple primary cancer will be increased, gradually. Herein, we experienced a case of a 83-year-old male patient with metachronous triple primary cancer composed of gastric cancer, bladder cancer and lung cancer. We found the adenocarcinoma of stomach, transitional cell cancer of bladder and squamous cell carcinoma of lung. For its great rarity, we report this case with review of literatures about the history, criteria, incidence, site relationship and so on.