Background: It is not clear whether environmental exposure to dioxin affects the general population. The aim of this research is to evaluate sarcoma risk in relation to the environmental pollution caused by dioxin emitted by waste incinerators and industrial sources of airborne dioxin. The study population lives in a part of the Province of Venice (Italy), where a population-based cancer registry (Veneto Tumour Registry -RTV) has been active since 1987.

The overall proportion of incorrect decisions is not high and similar to those reported by other registries, but errors are correlated to the diagnostic evidence pattern. As a further check, we decided to revise clinical cases for the three sites mentioned manually, in order to reduce the numbers proportion of both prevalent cases, and all cytology-based diagnoses, so as to reduce the number of 'false positives'. Coverage of hospital discharge source has been extended in order to decrease the proportion of cases based only on pathology records.

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.

Limited endoscopy capacity usually represents the main barrier to the extension of screening to subjects older than 70, given the high positivity rate in this age group. We assessed CRC incidence and mortality by number of previous negative fecal immunochemical tests (FIT) among subjects turning 70. We selected persons aged 70 years who had received their last screening invitation when they were 68 or 69 years old within the populationbased screening program in the Veneto region of Italy. Subjects with a positive FIT were excluded. We calculated 10-year cumulative CRC incidence and mortality in cohorts of subjects having performed zero, one, two or three negative FITs over the last three screening rounds before turning 70. Out of 117 858 subjects included in the study (46.4% men), 33.7% had never participated in screening (zero negative FITs), 23.3% had had onenegative FIT, 20.1% two-negative FITs and 22.9% three negative FITs. The 10-year cumulative CRC incidence was 29.7 per 1000 subjects with zero FITs, and respectively, 14.5, 11.7 and 9.6 per 1000 subjects with one, two and three negative FITs. The corresponding figures for 10-year cumulative mortality were 9.3, 3.5, 2.2 and 2.1 per 1000 in the four study cohorts. Figures were roughly double for men than for women for all the study cohorts. In order to use more efficiently limited endoscopy resources, and to minimize the potential harms related to false positive results in the elderly, screening among people aged 70 to 74 might be restricted to those with zero previous negative FITs.