Where do the cancer registries collect the data from?
The registries collect data from hospitals, family doctors, local health authorities (ASL), and the regions, or their health agencies.
The following are the main sources are:
Hospital discharge notes
These notes hold a summary of every patient admission. The advantage of this source lies in the availability of the data for every admission on Italian territory, whether by a public or a private hospital. Their data is nearly always available in electronic format.
Anatomical and pathological cytology archives
These archives assure the highest level of accuracy of the diagnosis of individual cases following international coding rules. On the average, in Italy, over 80 percent of cases have a histo-pathological confirmation (morphological and tumour behaviour). The growing availability of archived information has enabled not only faster access to data, but also a greater acquisition of the characteristics of neoplasms (morphology of the cancer, biological structure, grading and classification).
Clinical records have a role in precising and integrating case data that computer processing is often not able to achieve. As a rule, the records are consulted at the hospital, and sometimes, though rarely, with the treating doctor.
Death certificates are historically one of the main sources for cancer registrations. The data is taken from the notifications, sent to local health authorities and the National Statistical Institute, containing the cause of death. Such a source proves essential for recovering cases missed in gathering incidence data.
Are they reliable sources?
The availability of these sources, often computerized and rich in information, has enabled the majority of the Italian cancer registries to collect, in addition to basic personal data (sex, age, date and place of birth, and residence) and the characteristics of single tumours (location, morphology and behaviour), a great deal of useful data for both the clinician and the epidemiologist. In fact, most registries collect data on the stage, grade, markers, receptor status, biological indications and the type of intervention and treatments given. Moreover, for many cancers (breast, cervical and, more recently, colo-rectal) the screening status is available, and used in estimating the efficacy of oncological screening.