What are they?

The cancer registries are organizations engaged in the gathering of information about those sick with cancer resident in a specified area.
They are needed because in Italy there is an obligation for hospitals, whether public or private, to keep all records of the diagnosis and treatment of tumours. In order to understand trends in the pathology of cancer it is necessary for someone to take on the tasks of investigating the information, codifying and archiving it, and making it available for study and research. It is the Italian cancer registries that undertake this work.
There are 34 registries covering in all a quarter of the Italian population.
The information collected includes the type of tumour diagnosed, the name, address, age and sex of the patient, the clinical circumstances in which the cancer was found, the current treatment and treatment history, and the development of the disease.
These data are essential for research into the causes of cancer, evaluation of the efficacy of treatments, planning preventive interventions and scheduling expenditure on health services.

Population registries and specialized registries.
Most of the registries are population registries. They gather data about the tumours of all residents of a specfic area, which could be a single city, an entire region or province, or the area covered by an ASL (Azienda Sanitaria Locale - local public bodies providing health services). The importance of the connection of collected data with residence lies in the fact that case histories collected in this way are not selected, but reflect the conditions of an area in which live people of all ages and all social strata.
The specialized registries, on the other hand, gather information on a single type of tumour (for example, tumours of the colon, the rectum and breasts), or for specific age groups (children aged 0 to 14, and adolescents aged 15 to 19).