Accuracy of the Lombardy Mesothelioma Registry: comparison with the autopsy database of Pavia University (Lombardy Region, Northern Italy).

Objectives: to evaluate the accuracy (completeness of case recording and diagnostic quality) of the Lombardy Mesothelioma Registry (Registro Mesoteliomi Lombardia, RML) through a comparison with the autopsy database of Pavia University (years 2000-2016).

Design: validation study.

Setting and participants: all mesothelioma records with incidence date between 01.01.2000 and 16.09.2016 were extracted from the RML. They were cross-referenced with deaths from any asbestos-related disease subjected to a forensic autopsy extracted from the archive of the Department of Public Health, Experimental and Forensic Medicine of Pavia University.

Main outcomes measures: using the postmortem diagnosis by Pavia University as the gold standard, RML sensitivity and specificity and their 95% confidence intervals (95%CI) were calculated using the Agresti-Coull formula.

Results: based on 141 deaths, the RML showed very good accuracy: specificity was 100% (95%CI 87%-100%; 32/32 deaths) and sensitivity 94% (95%CI 87%-97%; 102/109 deaths). The 7 false negative cases either were missed by the RML (N. 4) or had been wrongly classified as non-mesotheliomas (N. 3) because the diagnosis was made or confirmed only postmortem after a forensic autopsy.

Conclusions: RML accuracy (completeness and diagnostic quality) was very high. No false positive was found and the few false negatives were due to lack of notification of mesotheliomas diagnosed postmortem to the registry. Forensic pathologists should be made aware that mesothelioma notification to the regional mesothelioma registry is important and compulsory.