In an analysis of Surveillance, Epidemiology, and End Results (SEER) data reported in a research letter in JAMA Oncology, Caitlin C. Murphy, PhD, MPH, and colleagues found that a substantial proportion of patients diagnosed with an incident cancer in 2019 had a history of prior cancer diagnosis.
Caitlin C. Murphy, PhD, MPH
Study Details
Data from the SEER database were analyzed to determine history of prior cancer, of the same or different type, among patients aged ≥ 18 years diagnosed with an incident cancer in 2019. In a previous study, the investigators found 18.4% of patients newly diagnosed with cancer from 2009 to 2013 had a previous cancer diagnosis.
Key Findings
Among 135,117 persons diagnosed with an incident cancer in 2019 in the SEER database, 108,940 (80.6%) had no prior cancer and 26,177 (19.4%) had any prior cancer. Those with prior cancer included 2,539 (1.9%) with cancer of the same type; 11,629 (8.6%) with cancer of a different type; and 12,009 (8.9%) with cancer of unknown type.
Prior cancer of a different type was more common among patients aged ≥ 65 years (14.1%, 95% CI = 13.8%–14.4%) vs 18 to 49 years (1.6%, 95% CI = 1.4%–1.8%); men (10.3%, 95% CI = 10.1%–10.6%) vs women (8.9%, 95% CI = 8.7%–9.2%); and White patients (11.0%, 95% CI = 10.8%–11.2%) vs Black patients (5.7%, 95% CI = 5.2%–6.1%).
Findings regarding prevalence of prior cancer were generally similar across patient groups with the five most common incident cancers (female breast, colorectal, lung, and prostate cancers, and melanoma).
Patients diagnosed with local vs distant-stage incident cancers were more likely to have prior cancer of a different type among those with colorectal cancer (adjusted odds ratio [OR] = 1.33, 95% CI = 1.11–1.60) and lung cancer (adjusted OR = 1.59, 95% CI = 1.41–1.79).
The investigators stated, “The increase in number of persons newly diagnosed with cancer in the United States (from 1,618,263 in 2013 to 1,737, 969 in 2019), combined with the increasing prevalence of prior cancer (from 18.4% in a previous study to 19.4%), show an approximately 15% increase in the number of cancer survivors diagnosed with a new cancer in 6 years… Recommendations against excluding patients from clinical trials solely on the basis of prior cancer are supported by growing evidence that persons newly diagnosed with cancer who have survived a prior cancer of a different type have equivalent survival compared with those without prior cancer.”
Dr. Murphy, of UTHealth Houston School of Public Health, is the corresponding author for the JAMA Oncology article.
Disclosure: The study was supported by the National Cancer Institute, Cancer Prevention and Research Institute of Texas, and others. For full disclosures of the study authors, visit jamanetwork.com.
