The survey methods for confirming the epidemicity and identifying the possible causes of the cancer epidemic can be different from those for infectious diseases. The procedure for confirming whether the outbreak is epidemic or not is quite different. Household survey for identifying cancer cases and residents actually living at the area should be done. Hospital survey for medical record review should be performed to identify all cancer cases among the residents of the outbreak area and confirmig the final diagnoses of the cancer cases. Comparing the level of cancer incidence or mortality with other areas can be done by using Poisson distribution, or calculating SIR (Standard Incidence Ratio) from cumulative incidence rates. Case-control study can be conducted to identify the etiologic, factors of the cancer epidemic and to establish strategy for preventing further recurrence of the outbreak.