A prior cancer history was common in a quarter of adults 65 or older and 11 percent of younger patients diagnosed with cancer from 2009 to 2013.
Why The Research Is Interesting: The number of cancer survivors in the United States is growing and is estimated to reach 26 million by 2040. Understanding how common a subsequent cancer is among patients with a history of cancer is important for understanding ongoing or new cancer risk in survivors.
Who and When: 740,990 people diagnosed with new cancer from 2009 through 2013.
How (Study Design): This is an observational study. Because researchers are not intervening for purposes of the study they cannot control natural differences that could explain study findings.
Results: The frequency of prior cancer among patients diagnosed with new cancer ranged from 3.5 percent to 36.9 percent and most prior cancers were diagnosed in a different cancer site.
Patients diagnosed with new cancer who have a history of cancer may be excluded from clinical trials and underrepresented in research. Understanding the impact of prior cancer is important to improve research, disease outcomes and patient experience.