Quality control on digital cancer registration

Population-based cancer registration methods are subject to internationally-established rules. To ensure efficient and effective case recording, population-based cancer registries widely adopt digital processing (DP) methods. At the Veneto Tumor Registry (RTV), about 50% of all digitally-identified (putative) cases of cancer are further profiled by means of registrars' assessments (RAs). Taking these RAs for reference, the present study examines how well the registry's DP performs. A series of 1,801 (putative) incident and prevalent cancers identified using DP methods were randomly assigned to two experienced registrars (blinded to the DP output), who independently re-assessed every case. This study focuses on the concordance between the DP output and the RAs as concerns cancer status (incident versus prevalent), topography, and morphology. The RAs confirmed the cancer status emerging from DP for 1,266/1,317 incident cancers (positive predictive value [PPV] = 96.1%) and 460/472 prevalent cancers (PPV = 97.5%). This level of concordance ranks as optimal, with a Cohen's K value of 0.91. The overall prevalence of false-positive cancer cases identified by DP was 2.9%, and was affected by the number of digital variables available. DP and the RAs were consistent in identifying cancer topography in 88.7% of cases; differences concerned different sites within the same anatomo-functional district (according to the International Agency for Research on Cancer [IARC]) in 9.6% of cases. In short, using DP for cancer case registration suffers from only trivial inconsistencies. The efficiency and reliability of digital cancer registration is influenced by the availability of good-quality clinical information, and the regular interdisciplinary monitoring of a registry's DP performance.

Automated summary

Population-based cancer registration methods follow international rules and often adopt digital processing methods for efficient case recording. This study examines the performance of digital processing (DP) at the Veneto Tumor Registry, comparing it with registrars' assessments (RAs). The results show a high level of concordance between DP and RAs in cancer status, topography, and morphology. The study highlights the importance of good-quality clinical information and regular interdisciplinary monitoring for the efficiency and reliability of digital cancer registration.