Characteristics and Survival of Korean Anal Cancer From the Korea Central Cancer Registry Data

Purpose: In Korea, anal cancer is rare disease entity with specific clinical characteristics. Therefore, no survival analysis with a sufficient patient population has been performed. The aim of this study was to evaluate the characteristics of Korean anal cancer, focusing on the survival according to tumor histologies, sex, and a specific age group, using the nationwide cancer registry. Methods: Using the Korea Central Cancer Registry, we analyzed a total of 2,552 cases from 1993 to 2010. We assessed the 5-year relative survival by using tumor histology. In addition, survival differences of Surveillance Epidemiology and End Results (SEER) stage were analyzed for both sexes and for young-age cancer (younger than 40 years) and advanced-age cancer (older than 70 years). Results: The 5-year relative survival among anal cancer patients increased from 38.9% for the period 1993-1995 to 65.6% for the period 2006-2010. The anal squamous cell carcinoma was the most common histology and showed better survival than other types of cancer. Females demonstrated better survival than males in all SEER stages. The 5-year survivals for patients in whom anal cancer developed before the age of 40 and at or after the age of 40 were 62.4% and 51.6%, respectively. The 5-year survival for patients in whom cancer developed at or after the age of 70 was much worse than that for patients in whom the cancer had developed prior to that age. Conclusion: Korean anal cancer has certain distinctive characteristics of survival according to tumor histology, sex, and age. Despite limitations on available data, this study used the nationwide database to provide important information on the survival of Korean patients with anal cancer.