Incidence features of second primary malignancy among gastric cancer survivors, 1992-2012

Background: With the expanding population of cancer survivors, screening for second primary malignancy (SPM) is one issue concerning survivorship care. This study aimed to evaluate the potential risk of developing SPMs and determine the features of SPMs among patients after the diagnosis of gastric cancer (GC). Methods: We identified 33,705 GC patients from the Surveillance, Epidemiology, and End Results Program (SEER) database. The standardized incidence ratios (SIRs) were calculated to estimate the risk of SPMs. The SIRs were stratified by age, race, stage, and latency period since GC diagnosis. Results: A total of 2,018 among 33,705 GC patients developed SPMs. Compared with the general population, these GC survivors had higher risks of developing second malignancies of the esophagus, stomach, small intestine, colon, pancreas, and thyroid. Conversely, these GC survivors had lower chances of developing prostate and female breast cancer. Conclusions: In stratified analyses, we identified the features associated with a higher risk of developing SPMs, including age between 20 and 39 years, latency between 60 and 119 months, localized stage, and American Indian/Alaska Native ethnicity. Hence, GC survivors are at a higher risk of developing SPMs than the general population. Careful attention and continuous surveillance should be used when treating these patients.