Examination of Preliminary Cancer Surveillance Data from the National Program of Cancer Registries, Diagnosis Year 2012.

Background: The United States Cancer Statistics (USCS) are the official federal cancer statistics and contain the most complete and accurate data. Yet, the data are typically older than 24 months by the time they are published. The National Program of Cancer Registries (NPCR) contributes 96% of the data in USCS and has been collecting preliminary data since 2000, though the quality of these data has not been published. The objective of this analysis is to determine how accurately preliminary cancer data submitted by NPCR grantees predict cancer rates eventually published in USCS.

Methods: Cancer data were obtained for diagnosis year 2012 among all cancer sites combined and a subset of 20 cancer sites that were used to test completeness of case ascertainment. Age-adjusted incidence rates (IR), rate ratios (RR), and 95% CIs were calculated for data submitted in November 2013 (NPCR preliminary, or 12-month data)—794,413 cases—and compared to USCS, which uses data submitted in November 2014 (24-month data)—1,529,078 cases.

Results: For all cancer sites and all races combined, the incidence rates for the NPCR preliminary data were slightly lower than the rate obtained through USCS (401.3 vs 440.3), but showed comparability (RR = 0.91). Regardless of race, 75% of the cancer sites had rate ratios of at least 0.90. For hospitals or clinics, the site-specific RRs were high, but RRs were more variable for other non-hospital centers and were lower for cases obtained from death certificates and autopsies. More than half (56%) of the US population and 87% of cancer cases diagnosed in 2012 were represented by the states included in the preliminary data set.

Discussion: This is the first known study examining cancer incidence rates calculated using earlier cancer surveillance data than is traditionally used. The strengths of this analysis include the representativeness of the sample and comparability with the USCS data. Our results also show that, compared to other sources, early reporting from hospitals most accurately estimates cancer rates in USCS.

Conclusion: Preliminary cancer data may accurately estimate the official federal cancer incidence rates for the 2012 diagnosis year and supports the possibility of using these data as an early preview of cancer incidence rates.