Epidemiological, Clinical and Pathological Characteristics of Gastric Tumors. The Population Based Specialized Registry in Northern Italy

Background: Gastric cancer (GC) is the 5th most common cancer and the 3rd leading cause of cancer-related deaths worldwide. GC incidence and mortality rates vary widely across different geographical areas. In Italy the province of Cremona is characterized by an high incidence, compared with the national one. For these reason a specialized population based registry was set up.

Methods: Up to now the collection encompasses all the GC cases diagnosed in Cremona province from January 1st 2010 until December 31st 2015. The main data sources were represented by the pathological records and the patient clinical charts. Data were collected following AIRTum (Associazione Italiana Registri Tumori) and IARC (International Agency for Research on Cancer) cancer registration recommendations. Territory of Cremona province comprises 3 main public hospitals and 3 private structures. All of them refer to 2 pathology services. All these facilities were involved in the project. A minority of patients usually ask for different surgery and move to neighboring provinces, mainly Milan and Brescia. An official collaboration with these facilities was signed in order to have the access to the data of their patients who were inhabitants of the province of Cremona. A multidisciplinary team of clinicians (oncologists, gastroenterologists, general practitioners, surgeons), pathologists, geneticists and methodologists (epidemiologists, hygienists) was involved in the project.

The registration of an incident case usually began with the pathological confirmation of diagnosis of cancer. Subsequently, medical records were obtained. For each case the following variables were registered: personal and familiar data; imaging studies performed; details on surgery and other treatments received; host genetic background and biomolecular characteristic, social and environmental factors. All data were collected, recorded, protected and processed in accordance to AIRTum-IARC (International Agency for Research on Cancer) cancer registration recommendations and national privacy laws.

Any age at diagnosis was included. At the time of diagnosis patients had to be inhabitants of the province of Cremona (districts of Crema, Cremona or Casalmaggiore). Only diagnoses of primary gastric neoplasms were considered. Precancerous lesions and relapsed tumor diagnoses were not considered. For the specific purposes of our study, we didn't record cases diagnosed based on Death Certificate Only (DCO)"in situ" tumors were also included.

Site of the tumor at diagnosis was stomach or gastro-esophageal junction (GEJ), ref. cod. ICD-X C16, according to the UICC, 7th ed.